Clinical communications Flutter of left ventricular structures in patients with aortic regurgitation, with special reference to patients with associated mitral stenosis Ivan D'Cruz, M.D., F.R.C.P.(E) Howard C. Cohen, M.D. Ravindra Prabhu, M.D. Takao Ayabe, M.D. Gerald Glick, M.D. Chicago, Ill.
We have found that fine fluttering or vibratory motion of the ventricular septum (VS) in echocardiograms of patients with the diastolic murmur of aortic regurgitation (AR) correlates well with the presence of an anteriorly directed regurgitant jet seen on aortography. In addition, we have observed anterior mitral valve leaflet flutter (mitral flutter) in two out of four patients with AR and associated stenotic mitral valves. Mitral flutter is rarely reported in the presence of this combination of valvular lesions. 1, 2 Certain additional aspects of mitral and VS flutter due to AR, especially with coexisting mitral stenosis (MS), have hitherto escaped close attention. The fixed duration of mitral flutter but not of VS flutter during diastolic periods of varying length in patients with AR and MS is one such observation being reported in this communication. Methods
Echocardiography was performed in 45 patients with AR who ranged in age from 9 to 74 years. The diagnosis was based on the auscultation of a typical decrescendo basal early diastolic murmur. Phonocardiography, done in most of the From the Cardiovascular Institute, Department of Medicine, Michael Reese Hospital and Medical Center, and the University of Chicago Pritzker School of Medicine, Chicago, Ill. This study was supported in part by the Jeanette and Alex D. Nast Fund for Cardiovascular Research and by the Michael Reese Medical Research Institute Council. Received for publication July 28, 1975. Reprint requests: Ivan D'Cruz, M.D., Cardiovascular Institute, Michael Reese Hospital and Medical Center, 29th St. and Ellis Ave., Chicago, Ill. 60616.
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patients, confirmed the presence of such a murmur. Associated MS was present in four cases and discrete fixed subvalvular aortic stenosis in one case. Aortic systolic murmurs were usually present but clinically significant aortic valvular stenosis, with two exceptions, was absent or minimal in these patients. Two patients had prosthetic aortic valves and three had prosthetic mitral valves. All echocardiograms were obtained on a Picker Echoview 10 ultrasonoscope, connected to a stripchart Honeywell Visicorder. Echoes from the mitral valve, aortic valve, and the VS were obtained by standard techniques2 -5 The echoes of the anterior and posterior leaflets of the mitral valve were examined for the presence of diastolic flutter. Mitral flutter movements were studied with respect to (1) amplitude, which was estimated by subtracting the thickness of the leaflet {best seen in systole) from the maximum apparent span of oscillation of the fluttering valve in diastole, (2) duration, by examining the echo of the anterior leaflet of the mitral v a n e during diastole, and (3) frequency of vibrations per second, by using a • 10 magnifying loupe. The VS echo, at different levels from high VS (at mitral valve level) to low VS {between mitral valve and apex), was examined for the presence of flutter. Septal flutter was studied with respect to duration, frequency, and amplitude (slight, moderate, marked). Cineangiograms of aortic root injections obtained in 19 of the 45 patients were examined 6 with particular attention to the direction of the regurgitant jet and the degree of AR.
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Fig. 1A, Echocardiogram of a 15-year-old girl with aortic regurgitation showing diastolic flutter of the mitral valve and ventricular septum. The anterior mitral leaflet exhibits both coarse and fine oscillations. Arrow No: 1 points to mitral flutter and arrow No. 2 to septal flutter. VS, ventricular septum; AM, anterior mitral leaflet; PM, posterior mitral leaflet; PWLV, posterior wall of left ventricle.
Results A fine fluttering or v i b r a t o r y m o t i o n was visible on the left side of t h e VS in 12 o u t of a t o t a l of 45 patients, m a t c h i n g fine flutter of t h e a n t e r i o r m i t r a l leaflet in frequency of oscillation. In six of these 12 it was of slight degree, restricted to early diastole, and found only on the high VS (at t h e level of the free edge of the a n t e r i o r m i t r a l leaflet in diastole). Of the o t h e r six patients, the s e p t a l flutter was holodiastolic a n d of g r e a t e r degree, involving the full septal thickness, in four; in these four, septal flutter was visible over t h e lower {distal) s e p t u m , a l t h o u g h of lesser degree t h a n on the higher s e p t u m . I n t h e r e m a i n i n g t w o p a t i e n t s it was seen only on the left aspect of t h e VS, t h e duration of flutter v a r y i n g f r o m holodiastolic (over the high s e p t u m ) to early diastolic (over the distal or lower s e p t u m ) . A o r t o g r a p h y was p e r f o r m e d in 19 of the 45 patients and confirmed incompetence of t h e aortic valve. T h e p a t i e n t s were divided into t w o categories according to the direction of the regurgitant jet as viewed in the left a n t e r i o r oblique projection. In the first group c o m p o s e d of 12 patients the m a i n jet, or a m a j o r c o m p o n e n t of the b r o a d fan-shaped jet, was directed a n t e r i o r l y so as to impinge u p o n the VS. S e p t a l flutter was present in seven of these 12 patients. In t h e
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Fig. 1B. Magnification of the area indicated by arrows Nos. 1 and 2.
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Fig, 2. Echocardiogram of a 30-year-old woman with aortic regurgitation and mitral stenosis. A fine diastolic flutter is visible on the left aspect of the ventricular septum but not on the mitral valve. Septal flutter is present during the whole of diastole, including the longer postextrasystolic diastolic periods. PVC, premature ventricular contraction. The arrows indicate septal flutter.
second group of seven patients, the r e g u r g i t a n t j e t was directed centrally or posteriorly, a w a y from the septum. Septal flutter was n o t seen in these cases. Thus, in those p a t i e n t s who were studied b y aortography, septal flutter was associated invariably with an anteriorly directed aortic regurgit a n t jet, whereas none of t h e p a t i e n t s w i t h posteriorly directed jets d e m o n s t r a t e d VS flutter. N o correlation was found between severity of aortic regurgitation and a m p l i t u d e of m i t r a l flutter. F o r t y of the 42 p a t i e n t s w i t h o u t m i t r a l valve prosthesis showed a fine flutter of t h e a n t e r i o r mitral leaflet. T h e a m p l i t u d e of this flutter varied from 3 to 7 mm., with an average of 4.4 m m . Although usually of g r e a t e s t a m p l i t u d e in e a r l y diastole, the flutter was holodiastolic in all, except in the four p a t i e n t s with associated MS, two of w h o m had only early m i t r a l flutter a n d t h e remaining two no mitral flutter a t all. T h e frequency of the flutter varied f r o m 70 to 260 cycles per second. In t h r e e cases in sinus r h y t h m , a m u c h coarser, irregular, and slower u n d u l a t i o n was superimposed on the fine flutter (Fig. 1). T h e thickness of the anterior m i t r a l leaflet {measured during systole) varied from 1 to 4 m m . , w i t h a m e a n of 2.0 m m . Thirty-five of the 42 also showed flutter of the posterior m i t r a l leaflet, which was always of lesser a m p l i t u d e t h a n t h a t of the 686
anterior leaflet in t h e s a m e p a t i e n t . T h e s e v e n patients in w h o m posterior leaflet flutter was n o t seen included two in w h o m t h e leaflet echoes could not be recorded and t h e four with MS. Diastolic flutter of anterior c h o r d a e t e n d i n e a e was noted in one p a t i e n t and of posterior c h o r d a e in two others, In the four p a t i e n t s with M S t h e m i t r a l leaflets showed echoes suggestive of sclerotic or calcific changes; the E - F slope of the a n t e r i o r leaflet was a b n o r m a l l y shallow and t h e posterior leaflet m o v e d anteriorly during diastole instead of posteriorly as in the normal. In two of the p a t i e n t s with MS, septal flutter was m a r k e d , in the absence of mitral flutter (Fig. 2). T h e third p a t i e n t with M S had atrial fibrillation w i t h cycle lengths Varying from 0.70 to 1.78 sec. W h e n the cycle length was short a n d the diastolic intervals 0.60 sec. or less, the m i t r a l flutter was holodiastolic, b u t with longer lengths the v i b r a t o r y m o t i o n of the anterior m i t r a l leaflet was 0.60 sec. in duration; its cessation coincided w i t h a n a b r u p t decrease in E-F slope (Fig. 3). T h e echocardiog r a m of the fourth p a t i e n t with MS, who was also in atrial fibrillation, showed a similar cessation of vibrations of the a n t e r i o r m i t r a l v a l v e leaflet a t the point of a b r u p t change of the diastolic slope (Fig. 4). Fig. 4 also d e m o n s t r a t e s t h a t septal a n d December, 1976, Vol. 92, No. 6
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Duration of Diastolic Mitral Valve Fluttering (sec) Fig. 3. Echocardiogram of a 50-year-old woman with aortic regurgitation and mitral stenosis. The anterior mitral leaflet shows a fine diastolic flutter. In the first three beats, with long diastolic periods, the mitral flutter ceases abruptly about 0.6 sec. after the E point.
Fig. 4. Echocardiogram of a 53-year-old man with aortic regurgitation and mitral stenosis. A fine flutter is seen on the left aspect of the ventricular septum throughout diastole. A similar flutter is evident on the anterior mitral leaflet, but in the second and fourth beats (which have long diastolic periods), the mitral flutter ceases abruptly about 0.5 sec. after the E point. In the second beat, X indicates the beginning of mitral and septal flutter; the arrow pointing downward marks the termination of mitral flutter, whereas septal flutter terminates much later, at enddiastole (arrow pointing upward). Slow oscillations (approximately 6 per sec.) of the mitral valve due to atrial flutter-fibrillation, are particularly well seen in the last beat (bar).
m i t r a l f l u t t e r b e g i n s i m u l t a n e o u s l y (X), b u t mitral flutter ends early (downward pointing arrow), w h e r e a s s e p t a l f l u t t e r p e r s i s t s u n t i l t h e e n d of d i a s t o l e ( u p w a r d p o i n t i n g a r r o w ) . Also, t h e coarse u n d u l a t i o n s of t h e a n t e r i o r l e a f l e t of t h e
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m i t r a l v a l v e t h a t h a v e b e e n a t t r i b u t e d to a t r i a l f i b r i l l a t i o n ( b r a c k e t ) differ s i g n i f i c a n t l y f r o m t h e fine f l u t t e r i n g a s s o c i a t e d w i t h A R . I n t w o p a t i e n t s w i t h c a l c i f i c a t i o n of t h e m i t r a l a n n u l u s ( b u t n o t MS), t y p i c a l f l u t t e r was e v i d e n t o n t h e 687
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Fig, 5. Echocardiogram showing diastolic flutter of the anterior mitral cusp in a 60-year-oldwoman with aortic regurgitation. (A) A calcified nonfluttering mitral annulus (MVA) is responsible for the broad dense echo, situated posterior to that of the anterior mitral cusp, which partly obscures the posterior mitral cusp. The horizontal bar indicates the duration of mitral flutter. (B) Fine flutter of the anterior mitral cusp continues throughout the prolonged diastole after a premature ventricular beat. Cardiac catheterization in this patient proved the absence of mitral stenosis.
mitral valve b u t n o t on the a n n u l u s (Fig. 5). Of the three patients with A R and a prosthetic mitral S t a r r - E d w a r d s valve, early diastolic flutter of the ball and the s e p t u m was visible in two (Fig. 6). One patient also exhibited fine flutter on the endocardium of the left v e n t r i c u l a r posterior wall. A o r t o g r a p h y in this case d e m o n s t r a t e d t h a t a fan-shaped regurgitant jet struck the VS anteriorly, the prosthetic mitral valve centrally, a n d the posterior left ventricular wall posteriorly. A o r t o g r a p h y in a n o t h e r patient with a prosthetic mitral valve, who exhibited septal flutter on echocardiography, revealed an anteriorly directed regurgitant stream. A o r t o g r a p h y was n o t performed in the third patient with m i t r a l valve prosthesis. Neither septal nor endocardial flutter was detected on e c h o c a r d i o g r a p h y in 11 o t h e r patients with prosthetic mitral valves (but no aortic regurgitation) studied by us; septal or endocardial flutter, in a patient with a prosthetic
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Fig. 6. Echocardiogram of a 45-year-old woman with a prosthetic Starr-Edward~ mitra! valve. The upper solid arrow indicates septal flutter, the lower solid arrow left ventricular posterior wall endocardial flutter, and the open arrow flutter of the prosthetic ball valve in diastole (faintly visible). PB, posterior ball.
mitral valve, thus appears a reliable sign of aortic regurgitation.
Discussion The echocardiographic a p p e a r a n c e of diastolic flutter of the mitral valve in patients with A R was first described in 1966 by J o y n e r and associates 7 and further studied by Winsberg a n d associates I and Pridie and associates. 2 I t has proved a useful indirect sign of A R since the echo obtained from the a o r t i c valve in this condition does not itself have any specific or c o n s t a n t diagnostic findings. 3' 4, 8, 9 Of 35 patients with clinical signs of A R w i t h o u t MS reported by Winsberg and co-workers, 1 11 h a d a "characteristic fluttering m o t i o n of the a n t e r i o r mitral leaflet" and five others h a d "equivocal
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Fig. 7. Mitral flutter in three patients with no auscultatory evidence of aortic regurgitation. Panel A shows the echocardiogramof a 60-year-oldwoman with mitral regurgitation and mitral annulus calcification. Panel B is the echocardiogram of a 28-year-old woman with mitral regurgitation and cardiomyopathy. Panel C is the echocardiogram of a 66:year-old woman with severe anemia but no mitral regurgitation.
flutter." In the series of 75 patients of Pridie and associatesf "rapid oscillation of the m i t r a l valve in diastole," was present in 10. No fewer t h a n 22 of 29 patients reported by Friedewald and associates 1~ showed mitral flutter. Cope and associates 11 recently reported 46 patients with A R who demonstrated mitral flutter, of w h o m 17 showed VS flutter. F o r t y of our 42 patients with AR (excluding three patients with m i t r a l prostheses) exhibited rapid mitral oscillation of a n amplitude of 3 mm. or more. T h e higher incidence of mitral flutter in the more recent reports could perhaps be a t t r i b u t e d to different recording equipment. Our findings are in a g r e e m e n t with those of Pridie and associates, ~ who r e m a r k e d t h a t no correlation existed between the severity of AR and the presence of mitral flutter. We observed t h a t the severity of mitral flutter was not proportional to the severity of A R as revealed by aortography: Diastolic mitral flutter was considered highly specific for AR by Winsberg and associates. 1 It is now becoming increasingly evident, however, t h a t a similar fine vibratory m o t i o n of the mitral valve can occur in other types of h e a r t disease, including ventricular septal defects and right-toleft shunts, 12 as well as in n o r m a l subjects. ~ We, too, have frequently e n c o u n t e r e d mitral flutter in the absence of AR, particularly in patients with
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mitral regurgitation (Fig. 7). In c o n t r a s t to patients with aortic regurgitation, who exhibit a greater amplitude of flutter on the anterior t h a n posterior mitral cusp, mitral flutter in p a t i e n t s without aortic regurgitation is m o r e m a r k e d on the posterior mitral cusp. If the nonspecificity of m i t r a l flutter as an echocardiographic sign of A R is confirmed b y future experience, the presence of septal flutter (which we have not observed in any condition other t h a n AR) m a y assume greater diagnostic importance. Only one of nine patients in the series of Winsberg and associates I with combined M S a n d AR exhibited diastolic mitral flutter; it was absent in all 20 of the patients with this combination of valvular lesions in the series of Pridie a n d associates.: It is unlikely t h a t thickening or sclerosis of the mitral leaflets alone is responsible for absence of flutter in MS, because some of o u r patients without stenotic m i t r a l valves h a d equally thickened (4 mm.) cusps and yet showed typical mitral flutter. Stiffness of the leaflets, however, m a y be a factor. T w o of our patients with MS and atrial fibrillation d e m o n s t r a t e d flutter of the anterior mitral leaflet only in early and mid-diastole. In one of these patients, the duration of mitral flutter remained c o n s t a n t from beat to beat, irrespective of cycle length; in b o t h
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patients, cessation of mitral flutter occurred simultaneously with the end or an abrupt decrease of the E-F slope, after the anterior mitral leaflet had moved to a partly closed position. Continuation of VS flutter beyond this point (Fig. 4) indicates that AR had not yet ceased. The reason for the simultaneous end of mitral flutter and change in E-F slope has not yet been estabfished, but two possible explanations may be considered. (1) The marked decrease or reversal in diastolic pressure gradient between the left atrium and left ventricle produced by AR 14 may decrease the flow between the two to the extent that the stiff stenotic anterior leaflet of the mitral valve is no longer suspended, in a vibrating state, between two streams of f l o w - t h a t of left atrial emptying and the AR jet, 15 (2) As ventricular pressure rises during diastole the anterior mitral valve leaflet, abnormally tethered to the posterior leaflet, moves posteriorly until it is no longer subject to the direct effects of the regurgitant jet. In such a position the stenotic valve neither vibrates nor closes further during diastole. A fine diastolic vibration of the VS was noted in approximately one half of the patients with AR recently described by Friedewald and associates, TM in one third of those of Cope and associates, 11 and in one fourth of ours. Two recent reviews, however, devoted to echocardiography of the VS12, 16 and another to valvular heart disease" make no mention of VS flutter. The septal flutter of the high VS was restricted to early diastole in six of our patients; in these cases the vibrations were of small amplitude and detectable only on the left aspect of the VS. In six other patients, however, the septal flutter was of greater amplitude and longer duration; in four of these it extended throughout diastole, involved the whole thickness of the high VS, and existed even at low septal levels. Edwards and Burchell ~8in 1958 described local areas of endocardial thickening on the anterior mitral leaflet and on the VS which they called "jet" lesions. They postulated t h a t jet lesions may designate "possible sites of origin of murmurs in whole or in part, and in this regard may be utilized in the explanation of the particular positions of the maximal intensity of murmurs recorded during life." Vibration of the VS may help to explain why the early diastolic murmur of AR is usually very well heard at the left lower parasternal region. Based on our find-
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ings in a patients with a prosthetic mitral valve and aortic regurgitation, we suggest that the middiastolic and presystolic murmurs of the AustinFlint type that have been observed in such patients 19 may result from flutter of the ball of the artificial valve, the septum, or a combination of these. Thus, echocardiography provides the clinician not only with a diagnostic aid, but also with a means of understanding the genesis of some auscultatory signs. Aortography showed t h a t part or all of the regurgitant jet was directed anteriorly toward the VS in all patients with septal flutter, and toward the central portion or posterior wall of the left ventricular chamber in patients without septal flutter. The absence of septal flutter in some patients with AR directed anteriorly would suggest that other factors, such as velocity of the regurgitant jet, might also play a role in determining the presence or absence of septal vibration. Thus, as an echocardiographic sign of an aortic leak, VS flutter is less frequently encountered than mitral flutter, and is related to an anteriorly directed aortic regurgitant jet. VS flutter may be more specific, however, and in the presence of MS, flutter of the VS may be present alone (as in two of our patients), or may be of greater amplitude and duration than that of the mitral valve. The cessation of mitral flutter in mid-diastole in patients with MS, simultaneous with an abrupt decrease in E-F slope, is an intriguing finding t h a t requires further study with hemodynamic and angiocardiographic correlations.
Summary Echocardiography was performed in 45 patients with aortic regurgitation. Forty showed a high frequency diastolic flutter of the mitral valve, which was holodiastolic in all but the patients with associated mitral stenosis. Of four patients with coexisting mitral stenosis, mitral flutter was absent in two; in the other two, in atrial fibrillation, mitral flutter occurred, but only during a fixed interval after mitral valve opening, irrespective of cycle length. A fine flutter of similar frequency was observed on the left ventricular aspect of the ventricular septum in 12 patients. In six of these it was of slight degree and restricted to early diastole and the high septum; in four others (three of whom had associated mitral stenosis), the septal flutter
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was m o r e m a r k e d , h o l o d i a s t o l i c , a n d p r e s e n t over all p a r t s of t h e s e p t u m s c a n n e d ; i n two, i t w a s h o l o d i a s t o l i c over t h e h i g h s e p t u m b u t e a r l y diastolic a t lower s e p t a l levels. A o r t o g r a p h y p e r f o r m e d i n 19 p a t i e n t s s h o w e d t h a t s e p t a l f l u t t e r was p r e s e n t i n s e v e n of 12 patients in w h o m the r e g u r g i t a n t aortic jet was directed forward to the v e n t r i c u l a r septum, whereas in the other seven p a t i e n t s with no septal flutter, t h e j e t was d i r e c t e d a w a y f r o m t h e s e p t u m . S e p t a l f l u t t e r is u s e f u l as a n e c h o c a r d i o g r a p h i c sign of a o r t i c r e g u r g i t a t i o n , e s p e c i a l l y i n t h e p r e s e n c e of m i t r a l s t e n o s i s w h e n m i t r a l f l u t t e r m a y be a b s e n t or exceeded b y s e p t a l f l u t t e r i n both amplitude and duration, and when the mitral valve has been replaced by a prosthetic valve. V i b r a t i o n of t h e s e p t u m a p p e a r s t o b e a t t r i b u t a b l e to t h e r e g u r g i t a n t a o r t i c j e t i m p i n g i n g o n i t a n d m a y c o n t r i b u t e to t h e p r o d u c t i o n a n d r a d i a t i o n of t h e c h a r a c t e r i s t i c d i a s t o l i c m u r m u r of a o r t i c r e g u r g i t a t i o n . REFERENCES
1. Winsberg, F., Gabor, E. F., and Hernberg, J. G.: Fluttering of the mitral valve in aortic insufficiency, Circulation 41:225, 1970. 2. Pridie, R. B., Benham, R., and Oakley, C. M.: Echocardiography of the mitral valve in aortic valve disease, Br. Heart J. 33:291, 1971. 3. Gramiak, R., and Shah, P. M.: Echocardiography of the normal and diseased aortic valve, Radiology 91:1, 1970. 4. Hernberg, J., Weiss, B., and Keegan, A.: The ultrasonic recording of aortic valve motion, Radiology 94:361, 1970. 5. Feigenbaum, H.: Echocardiography, Philadelphia, 1972, Lea & Febiger, Publishers, p. 37. 6. Hunt, D., Baxley, W. A., Kennedy, J. W., Judge, T. P., Williams, J. E., and Dodge, H. T.: Quantitative evaluation of cineaortography in the assessment of aortic regurgitation, Am. J. Cardiol. 31:696, 1973.
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7. Joyner, C. R., Dyrda, I., Barrett, J. S., and Reid, J. M.: Behavior of the anterior leaflet of the mitral valve in patients with Austin-Flint murmur, Clin. Res. 14:251, 1966. 8. Feizi, O., Symons, C., and Yacoub, M.: Echocardiography of the aortic valve. I. Studies of normal aortic valve, or aortic stenosis, aortic regurgitation and mixed aortic valve disease, Br. Heart J. 36:341, 1974. 9. Castillo-Fenoy, A., Houeix, J. M., Veber, G., Klepacki, Piwnica, A., and Tricott, R.: L'~chocardiographie dans les valvulopathies aortiques, Arch. Mal. Coeur 67:827, 1974. 10. Friedewald, V. E., Futral, J. E., Kinard, S. S., and Phillips, V.: Oscillations of the interventricular septum in aortic insufficiency (abst.), J, Clin. Ultrasound Suppl. p. 60, 1974. 11. Cope,G. D., Kisslo, J. A., Johnson, M. L., and Myers, S.: Diastolic vibration of the interventricular septum in aortic insufficiency, Circulation 51:589, 1975. 12. Assad-Morell, J. L., Tajik, A. J., and Giuloni, E. R.: Echocardiographic analysis of the ventricular septum, Prog. Cardiovasc. Dis. 17:219, 1974. 13. Goldberg, S. J., Allen, H. D., and Sahn, D.: Pediatric and adolescent echocardiography, Chicago, 1975, Year Book Medical Publishel~, Inc., p. 99. 14. O'Brien, K. P., and Cohen, L. S.: Hemodynamic and phonocardiographic correlates of the Austin-Flint murmur, AM. HEARTJ. 77:603, 1969. 15. Ross, R. S., and Criley, J. M.: Cineangiocardiographic studies of the origin of cardiovascular physical signs, Circulation 30:255, 1964. 16. Sawaya, J., Longo, M: R., and Schlant, R. C.: Echocardiographic interventricularseptal wall motion and thickness: A study in health and disease, AM. HEART J. 87:681, 1974. 17. Teichholz, L. E.: Echocardiography in valvular heart disease, Prog. Cardiovasc. Dis. 17:281, 1975. 18. Edwards, J. E., and Burchell, H. B.: Endocardial and intimal lesions (jet impact) as possible sites of origin of murmur, Circulation 18:946, 1958. 19. Schaetter, R. A., McAnulty, J. H., Starr, A., and Rahimtoola, S.: Diastolic murmurs in the presence of StarrEdwards mitral prosthesis: With emphasis on the genesis of the Austin-Flint murmur, Circulation 51:402, 1975.
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We have found that fine fluttering or vibratory motion of the ventricular septum (VS) in echocardiograms of patients with the diastolic murmur of aortic regurgitation (AR) correlates well with the presence of an anteriorly directed regurgitant jet seen on aortography. In addition, we have observed anterior mitral valve leaflet flutter (mitral flutter) in two out of four patients with AR and associated stenotic mitral valves. Mitral flutter is rarely reported in the presence of this combination of valvular lesions. 1, 2 Certain additional aspects of mitral and VS flutter due to AR, especially with coexisting mitral stenosis (MS), have hitherto escaped close attention. The fixed duration of mitral flutter but not of VS flutter during diastolic periods of varying length in patients with AR and MS is one such observation being reported in this communication. Methods
Echocardiography was performed in 45 patients with AR who ranged in age from 9 to 74 years. The diagnosis was based on the auscultation of a typical decrescendo basal early diastolic murmur. Phonocardiography, done in most of the From the Cardiovascular Institute, Department of Medicine, Michael Reese Hospital and Medical Center, and the University of Chicago Pritzker School of Medicine, Chicago, Ill. This study was supported in part by the Jeanette and Alex D. Nast Fund for Cardiovascular Research and by the Michael Reese Medical Research Institute Council. Received for publication July 28, 1975. Reprint requests: Ivan D'Cruz, M.D., Cardiovascular Institute, Michael Reese Hospital and Medical Center, 29th St. and Ellis Ave., Chicago, Ill. 60616.
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patients, confirmed the presence of such a murmur. Associated MS was present in four cases and discrete fixed subvalvular aortic stenosis in one case. Aortic systolic murmurs were usually present but clinically significant aortic valvular stenosis, with two exceptions, was absent or minimal in these patients. Two patients had prosthetic aortic valves and three had prosthetic mitral valves. All echocardiograms were obtained on a Picker Echoview 10 ultrasonoscope, connected to a stripchart Honeywell Visicorder. Echoes from the mitral valve, aortic valve, and the VS were obtained by standard techniques2 -5 The echoes of the anterior and posterior leaflets of the mitral valve were examined for the presence of diastolic flutter. Mitral flutter movements were studied with respect to (1) amplitude, which was estimated by subtracting the thickness of the leaflet {best seen in systole) from the maximum apparent span of oscillation of the fluttering valve in diastole, (2) duration, by examining the echo of the anterior leaflet of the mitral v a n e during diastole, and (3) frequency of vibrations per second, by using a • 10 magnifying loupe. The VS echo, at different levels from high VS (at mitral valve level) to low VS {between mitral valve and apex), was examined for the presence of flutter. Septal flutter was studied with respect to duration, frequency, and amplitude (slight, moderate, marked). Cineangiograms of aortic root injections obtained in 19 of the 45 patients were examined 6 with particular attention to the direction of the regurgitant jet and the degree of AR.
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Fig. 1A, Echocardiogram of a 15-year-old girl with aortic regurgitation showing diastolic flutter of the mitral valve and ventricular septum. The anterior mitral leaflet exhibits both coarse and fine oscillations. Arrow No: 1 points to mitral flutter and arrow No. 2 to septal flutter. VS, ventricular septum; AM, anterior mitral leaflet; PM, posterior mitral leaflet; PWLV, posterior wall of left ventricle.
Results A fine fluttering or v i b r a t o r y m o t i o n was visible on the left side of t h e VS in 12 o u t of a t o t a l of 45 patients, m a t c h i n g fine flutter of t h e a n t e r i o r m i t r a l leaflet in frequency of oscillation. In six of these 12 it was of slight degree, restricted to early diastole, and found only on the high VS (at t h e level of the free edge of the a n t e r i o r m i t r a l leaflet in diastole). Of the o t h e r six patients, the s e p t a l flutter was holodiastolic a n d of g r e a t e r degree, involving the full septal thickness, in four; in these four, septal flutter was visible over t h e lower {distal) s e p t u m , a l t h o u g h of lesser degree t h a n on the higher s e p t u m . I n t h e r e m a i n i n g t w o p a t i e n t s it was seen only on the left aspect of t h e VS, t h e duration of flutter v a r y i n g f r o m holodiastolic (over the high s e p t u m ) to early diastolic (over the distal or lower s e p t u m ) . A o r t o g r a p h y was p e r f o r m e d in 19 of the 45 patients and confirmed incompetence of t h e aortic valve. T h e p a t i e n t s were divided into t w o categories according to the direction of the regurgitant jet as viewed in the left a n t e r i o r oblique projection. In the first group c o m p o s e d of 12 patients the m a i n jet, or a m a j o r c o m p o n e n t of the b r o a d fan-shaped jet, was directed a n t e r i o r l y so as to impinge u p o n the VS. S e p t a l flutter was present in seven of these 12 patients. In t h e
American Heart Journal
Fig. 1B. Magnification of the area indicated by arrows Nos. 1 and 2.
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Fig, 2. Echocardiogram of a 30-year-old woman with aortic regurgitation and mitral stenosis. A fine diastolic flutter is visible on the left aspect of the ventricular septum but not on the mitral valve. Septal flutter is present during the whole of diastole, including the longer postextrasystolic diastolic periods. PVC, premature ventricular contraction. The arrows indicate septal flutter.
second group of seven patients, the r e g u r g i t a n t j e t was directed centrally or posteriorly, a w a y from the septum. Septal flutter was n o t seen in these cases. Thus, in those p a t i e n t s who were studied b y aortography, septal flutter was associated invariably with an anteriorly directed aortic regurgit a n t jet, whereas none of t h e p a t i e n t s w i t h posteriorly directed jets d e m o n s t r a t e d VS flutter. N o correlation was found between severity of aortic regurgitation and a m p l i t u d e of m i t r a l flutter. F o r t y of the 42 p a t i e n t s w i t h o u t m i t r a l valve prosthesis showed a fine flutter of t h e a n t e r i o r mitral leaflet. T h e a m p l i t u d e of this flutter varied from 3 to 7 mm., with an average of 4.4 m m . Although usually of g r e a t e s t a m p l i t u d e in e a r l y diastole, the flutter was holodiastolic in all, except in the four p a t i e n t s with associated MS, two of w h o m had only early m i t r a l flutter a n d t h e remaining two no mitral flutter a t all. T h e frequency of the flutter varied f r o m 70 to 260 cycles per second. In t h r e e cases in sinus r h y t h m , a m u c h coarser, irregular, and slower u n d u l a t i o n was superimposed on the fine flutter (Fig. 1). T h e thickness of the anterior m i t r a l leaflet {measured during systole) varied from 1 to 4 m m . , w i t h a m e a n of 2.0 m m . Thirty-five of the 42 also showed flutter of the posterior m i t r a l leaflet, which was always of lesser a m p l i t u d e t h a n t h a t of the 686
anterior leaflet in t h e s a m e p a t i e n t . T h e s e v e n patients in w h o m posterior leaflet flutter was n o t seen included two in w h o m t h e leaflet echoes could not be recorded and t h e four with MS. Diastolic flutter of anterior c h o r d a e t e n d i n e a e was noted in one p a t i e n t and of posterior c h o r d a e in two others, In the four p a t i e n t s with M S t h e m i t r a l leaflets showed echoes suggestive of sclerotic or calcific changes; the E - F slope of the a n t e r i o r leaflet was a b n o r m a l l y shallow and t h e posterior leaflet m o v e d anteriorly during diastole instead of posteriorly as in the normal. In two of the p a t i e n t s with MS, septal flutter was m a r k e d , in the absence of mitral flutter (Fig. 2). T h e third p a t i e n t with M S had atrial fibrillation w i t h cycle lengths Varying from 0.70 to 1.78 sec. W h e n the cycle length was short a n d the diastolic intervals 0.60 sec. or less, the m i t r a l flutter was holodiastolic, b u t with longer lengths the v i b r a t o r y m o t i o n of the anterior m i t r a l leaflet was 0.60 sec. in duration; its cessation coincided w i t h a n a b r u p t decrease in E-F slope (Fig. 3). T h e echocardiog r a m of the fourth p a t i e n t with MS, who was also in atrial fibrillation, showed a similar cessation of vibrations of the a n t e r i o r m i t r a l v a l v e leaflet a t the point of a b r u p t change of the diastolic slope (Fig. 4). Fig. 4 also d e m o n s t r a t e s t h a t septal a n d December, 1976, Vol. 92, No. 6
Echocardiography in aortic regurgitation
Duration of Diastolic Mitral Valve Fluttering (sec) Fig. 3. Echocardiogram of a 50-year-old woman with aortic regurgitation and mitral stenosis. The anterior mitral leaflet shows a fine diastolic flutter. In the first three beats, with long diastolic periods, the mitral flutter ceases abruptly about 0.6 sec. after the E point.
Fig. 4. Echocardiogram of a 53-year-old man with aortic regurgitation and mitral stenosis. A fine flutter is seen on the left aspect of the ventricular septum throughout diastole. A similar flutter is evident on the anterior mitral leaflet, but in the second and fourth beats (which have long diastolic periods), the mitral flutter ceases abruptly about 0.5 sec. after the E point. In the second beat, X indicates the beginning of mitral and septal flutter; the arrow pointing downward marks the termination of mitral flutter, whereas septal flutter terminates much later, at enddiastole (arrow pointing upward). Slow oscillations (approximately 6 per sec.) of the mitral valve due to atrial flutter-fibrillation, are particularly well seen in the last beat (bar).
m i t r a l f l u t t e r b e g i n s i m u l t a n e o u s l y (X), b u t mitral flutter ends early (downward pointing arrow), w h e r e a s s e p t a l f l u t t e r p e r s i s t s u n t i l t h e e n d of d i a s t o l e ( u p w a r d p o i n t i n g a r r o w ) . Also, t h e coarse u n d u l a t i o n s of t h e a n t e r i o r l e a f l e t of t h e
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m i t r a l v a l v e t h a t h a v e b e e n a t t r i b u t e d to a t r i a l f i b r i l l a t i o n ( b r a c k e t ) differ s i g n i f i c a n t l y f r o m t h e fine f l u t t e r i n g a s s o c i a t e d w i t h A R . I n t w o p a t i e n t s w i t h c a l c i f i c a t i o n of t h e m i t r a l a n n u l u s ( b u t n o t MS), t y p i c a l f l u t t e r was e v i d e n t o n t h e 687
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Fig, 5. Echocardiogram showing diastolic flutter of the anterior mitral cusp in a 60-year-oldwoman with aortic regurgitation. (A) A calcified nonfluttering mitral annulus (MVA) is responsible for the broad dense echo, situated posterior to that of the anterior mitral cusp, which partly obscures the posterior mitral cusp. The horizontal bar indicates the duration of mitral flutter. (B) Fine flutter of the anterior mitral cusp continues throughout the prolonged diastole after a premature ventricular beat. Cardiac catheterization in this patient proved the absence of mitral stenosis.
mitral valve b u t n o t on the a n n u l u s (Fig. 5). Of the three patients with A R and a prosthetic mitral S t a r r - E d w a r d s valve, early diastolic flutter of the ball and the s e p t u m was visible in two (Fig. 6). One patient also exhibited fine flutter on the endocardium of the left v e n t r i c u l a r posterior wall. A o r t o g r a p h y in this case d e m o n s t r a t e d t h a t a fan-shaped regurgitant jet struck the VS anteriorly, the prosthetic mitral valve centrally, a n d the posterior left ventricular wall posteriorly. A o r t o g r a p h y in a n o t h e r patient with a prosthetic mitral valve, who exhibited septal flutter on echocardiography, revealed an anteriorly directed regurgitant stream. A o r t o g r a p h y was n o t performed in the third patient with m i t r a l valve prosthesis. Neither septal nor endocardial flutter was detected on e c h o c a r d i o g r a p h y in 11 o t h e r patients with prosthetic mitral valves (but no aortic regurgitation) studied by us; septal or endocardial flutter, in a patient with a prosthetic
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Fig. 6. Echocardiogram of a 45-year-old woman with a prosthetic Starr-Edward~ mitra! valve. The upper solid arrow indicates septal flutter, the lower solid arrow left ventricular posterior wall endocardial flutter, and the open arrow flutter of the prosthetic ball valve in diastole (faintly visible). PB, posterior ball.
mitral valve, thus appears a reliable sign of aortic regurgitation.
Discussion The echocardiographic a p p e a r a n c e of diastolic flutter of the mitral valve in patients with A R was first described in 1966 by J o y n e r and associates 7 and further studied by Winsberg a n d associates I and Pridie and associates. 2 I t has proved a useful indirect sign of A R since the echo obtained from the a o r t i c valve in this condition does not itself have any specific or c o n s t a n t diagnostic findings. 3' 4, 8, 9 Of 35 patients with clinical signs of A R w i t h o u t MS reported by Winsberg and co-workers, 1 11 h a d a "characteristic fluttering m o t i o n of the a n t e r i o r mitral leaflet" and five others h a d "equivocal
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Fig. 7. Mitral flutter in three patients with no auscultatory evidence of aortic regurgitation. Panel A shows the echocardiogramof a 60-year-oldwoman with mitral regurgitation and mitral annulus calcification. Panel B is the echocardiogram of a 28-year-old woman with mitral regurgitation and cardiomyopathy. Panel C is the echocardiogram of a 66:year-old woman with severe anemia but no mitral regurgitation.
flutter." In the series of 75 patients of Pridie and associatesf "rapid oscillation of the m i t r a l valve in diastole," was present in 10. No fewer t h a n 22 of 29 patients reported by Friedewald and associates 1~ showed mitral flutter. Cope and associates 11 recently reported 46 patients with A R who demonstrated mitral flutter, of w h o m 17 showed VS flutter. F o r t y of our 42 patients with AR (excluding three patients with m i t r a l prostheses) exhibited rapid mitral oscillation of a n amplitude of 3 mm. or more. T h e higher incidence of mitral flutter in the more recent reports could perhaps be a t t r i b u t e d to different recording equipment. Our findings are in a g r e e m e n t with those of Pridie and associates, ~ who r e m a r k e d t h a t no correlation existed between the severity of AR and the presence of mitral flutter. We observed t h a t the severity of mitral flutter was not proportional to the severity of A R as revealed by aortography: Diastolic mitral flutter was considered highly specific for AR by Winsberg and associates. 1 It is now becoming increasingly evident, however, t h a t a similar fine vibratory m o t i o n of the mitral valve can occur in other types of h e a r t disease, including ventricular septal defects and right-toleft shunts, 12 as well as in n o r m a l subjects. ~ We, too, have frequently e n c o u n t e r e d mitral flutter in the absence of AR, particularly in patients with
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mitral regurgitation (Fig. 7). In c o n t r a s t to patients with aortic regurgitation, who exhibit a greater amplitude of flutter on the anterior t h a n posterior mitral cusp, mitral flutter in p a t i e n t s without aortic regurgitation is m o r e m a r k e d on the posterior mitral cusp. If the nonspecificity of m i t r a l flutter as an echocardiographic sign of A R is confirmed b y future experience, the presence of septal flutter (which we have not observed in any condition other t h a n AR) m a y assume greater diagnostic importance. Only one of nine patients in the series of Winsberg and associates I with combined M S a n d AR exhibited diastolic mitral flutter; it was absent in all 20 of the patients with this combination of valvular lesions in the series of Pridie a n d associates.: It is unlikely t h a t thickening or sclerosis of the mitral leaflets alone is responsible for absence of flutter in MS, because some of o u r patients without stenotic m i t r a l valves h a d equally thickened (4 mm.) cusps and yet showed typical mitral flutter. Stiffness of the leaflets, however, m a y be a factor. T w o of our patients with MS and atrial fibrillation d e m o n s t r a t e d flutter of the anterior mitral leaflet only in early and mid-diastole. In one of these patients, the duration of mitral flutter remained c o n s t a n t from beat to beat, irrespective of cycle length; in b o t h
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patients, cessation of mitral flutter occurred simultaneously with the end or an abrupt decrease of the E-F slope, after the anterior mitral leaflet had moved to a partly closed position. Continuation of VS flutter beyond this point (Fig. 4) indicates that AR had not yet ceased. The reason for the simultaneous end of mitral flutter and change in E-F slope has not yet been estabfished, but two possible explanations may be considered. (1) The marked decrease or reversal in diastolic pressure gradient between the left atrium and left ventricle produced by AR 14 may decrease the flow between the two to the extent that the stiff stenotic anterior leaflet of the mitral valve is no longer suspended, in a vibrating state, between two streams of f l o w - t h a t of left atrial emptying and the AR jet, 15 (2) As ventricular pressure rises during diastole the anterior mitral valve leaflet, abnormally tethered to the posterior leaflet, moves posteriorly until it is no longer subject to the direct effects of the regurgitant jet. In such a position the stenotic valve neither vibrates nor closes further during diastole. A fine diastolic vibration of the VS was noted in approximately one half of the patients with AR recently described by Friedewald and associates, TM in one third of those of Cope and associates, 11 and in one fourth of ours. Two recent reviews, however, devoted to echocardiography of the VS12, 16 and another to valvular heart disease" make no mention of VS flutter. The septal flutter of the high VS was restricted to early diastole in six of our patients; in these cases the vibrations were of small amplitude and detectable only on the left aspect of the VS. In six other patients, however, the septal flutter was of greater amplitude and longer duration; in four of these it extended throughout diastole, involved the whole thickness of the high VS, and existed even at low septal levels. Edwards and Burchell ~8in 1958 described local areas of endocardial thickening on the anterior mitral leaflet and on the VS which they called "jet" lesions. They postulated t h a t jet lesions may designate "possible sites of origin of murmurs in whole or in part, and in this regard may be utilized in the explanation of the particular positions of the maximal intensity of murmurs recorded during life." Vibration of the VS may help to explain why the early diastolic murmur of AR is usually very well heard at the left lower parasternal region. Based on our find-
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ings in a patients with a prosthetic mitral valve and aortic regurgitation, we suggest that the middiastolic and presystolic murmurs of the AustinFlint type that have been observed in such patients 19 may result from flutter of the ball of the artificial valve, the septum, or a combination of these. Thus, echocardiography provides the clinician not only with a diagnostic aid, but also with a means of understanding the genesis of some auscultatory signs. Aortography showed t h a t part or all of the regurgitant jet was directed anteriorly toward the VS in all patients with septal flutter, and toward the central portion or posterior wall of the left ventricular chamber in patients without septal flutter. The absence of septal flutter in some patients with AR directed anteriorly would suggest that other factors, such as velocity of the regurgitant jet, might also play a role in determining the presence or absence of septal vibration. Thus, as an echocardiographic sign of an aortic leak, VS flutter is less frequently encountered than mitral flutter, and is related to an anteriorly directed aortic regurgitant jet. VS flutter may be more specific, however, and in the presence of MS, flutter of the VS may be present alone (as in two of our patients), or may be of greater amplitude and duration than that of the mitral valve. The cessation of mitral flutter in mid-diastole in patients with MS, simultaneous with an abrupt decrease in E-F slope, is an intriguing finding t h a t requires further study with hemodynamic and angiocardiographic correlations.
Summary Echocardiography was performed in 45 patients with aortic regurgitation. Forty showed a high frequency diastolic flutter of the mitral valve, which was holodiastolic in all but the patients with associated mitral stenosis. Of four patients with coexisting mitral stenosis, mitral flutter was absent in two; in the other two, in atrial fibrillation, mitral flutter occurred, but only during a fixed interval after mitral valve opening, irrespective of cycle length. A fine flutter of similar frequency was observed on the left ventricular aspect of the ventricular septum in 12 patients. In six of these it was of slight degree and restricted to early diastole and the high septum; in four others (three of whom had associated mitral stenosis), the septal flutter
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was m o r e m a r k e d , h o l o d i a s t o l i c , a n d p r e s e n t over all p a r t s of t h e s e p t u m s c a n n e d ; i n two, i t w a s h o l o d i a s t o l i c over t h e h i g h s e p t u m b u t e a r l y diastolic a t lower s e p t a l levels. A o r t o g r a p h y p e r f o r m e d i n 19 p a t i e n t s s h o w e d t h a t s e p t a l f l u t t e r was p r e s e n t i n s e v e n of 12 patients in w h o m the r e g u r g i t a n t aortic jet was directed forward to the v e n t r i c u l a r septum, whereas in the other seven p a t i e n t s with no septal flutter, t h e j e t was d i r e c t e d a w a y f r o m t h e s e p t u m . S e p t a l f l u t t e r is u s e f u l as a n e c h o c a r d i o g r a p h i c sign of a o r t i c r e g u r g i t a t i o n , e s p e c i a l l y i n t h e p r e s e n c e of m i t r a l s t e n o s i s w h e n m i t r a l f l u t t e r m a y be a b s e n t or exceeded b y s e p t a l f l u t t e r i n both amplitude and duration, and when the mitral valve has been replaced by a prosthetic valve. V i b r a t i o n of t h e s e p t u m a p p e a r s t o b e a t t r i b u t a b l e to t h e r e g u r g i t a n t a o r t i c j e t i m p i n g i n g o n i t a n d m a y c o n t r i b u t e to t h e p r o d u c t i o n a n d r a d i a t i o n of t h e c h a r a c t e r i s t i c d i a s t o l i c m u r m u r of a o r t i c r e g u r g i t a t i o n . REFERENCES
1. Winsberg, F., Gabor, E. F., and Hernberg, J. G.: Fluttering of the mitral valve in aortic insufficiency, Circulation 41:225, 1970. 2. Pridie, R. B., Benham, R., and Oakley, C. M.: Echocardiography of the mitral valve in aortic valve disease, Br. Heart J. 33:291, 1971. 3. Gramiak, R., and Shah, P. M.: Echocardiography of the normal and diseased aortic valve, Radiology 91:1, 1970. 4. Hernberg, J., Weiss, B., and Keegan, A.: The ultrasonic recording of aortic valve motion, Radiology 94:361, 1970. 5. Feigenbaum, H.: Echocardiography, Philadelphia, 1972, Lea & Febiger, Publishers, p. 37. 6. Hunt, D., Baxley, W. A., Kennedy, J. W., Judge, T. P., Williams, J. E., and Dodge, H. T.: Quantitative evaluation of cineaortography in the assessment of aortic regurgitation, Am. J. Cardiol. 31:696, 1973.
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7. Joyner, C. R., Dyrda, I., Barrett, J. S., and Reid, J. M.: Behavior of the anterior leaflet of the mitral valve in patients with Austin-Flint murmur, Clin. Res. 14:251, 1966. 8. Feizi, O., Symons, C., and Yacoub, M.: Echocardiography of the aortic valve. I. Studies of normal aortic valve, or aortic stenosis, aortic regurgitation and mixed aortic valve disease, Br. Heart J. 36:341, 1974. 9. Castillo-Fenoy, A., Houeix, J. M., Veber, G., Klepacki, Piwnica, A., and Tricott, R.: L'~chocardiographie dans les valvulopathies aortiques, Arch. Mal. Coeur 67:827, 1974. 10. Friedewald, V. E., Futral, J. E., Kinard, S. S., and Phillips, V.: Oscillations of the interventricular septum in aortic insufficiency (abst.), J, Clin. Ultrasound Suppl. p. 60, 1974. 11. Cope,G. D., Kisslo, J. A., Johnson, M. L., and Myers, S.: Diastolic vibration of the interventricular septum in aortic insufficiency, Circulation 51:589, 1975. 12. Assad-Morell, J. L., Tajik, A. J., and Giuloni, E. R.: Echocardiographic analysis of the ventricular septum, Prog. Cardiovasc. Dis. 17:219, 1974. 13. Goldberg, S. J., Allen, H. D., and Sahn, D.: Pediatric and adolescent echocardiography, Chicago, 1975, Year Book Medical Publishel~, Inc., p. 99. 14. O'Brien, K. P., and Cohen, L. S.: Hemodynamic and phonocardiographic correlates of the Austin-Flint murmur, AM. HEARTJ. 77:603, 1969. 15. Ross, R. S., and Criley, J. M.: Cineangiocardiographic studies of the origin of cardiovascular physical signs, Circulation 30:255, 1964. 16. Sawaya, J., Longo, M: R., and Schlant, R. C.: Echocardiographic interventricularseptal wall motion and thickness: A study in health and disease, AM. HEART J. 87:681, 1974. 17. Teichholz, L. E.: Echocardiography in valvular heart disease, Prog. Cardiovasc. Dis. 17:281, 1975. 18. Edwards, J. E., and Burchell, H. B.: Endocardial and intimal lesions (jet impact) as possible sites of origin of murmur, Circulation 18:946, 1958. 19. Schaetter, R. A., McAnulty, J. H., Starr, A., and Rahimtoola, S.: Diastolic murmurs in the presence of StarrEdwards mitral prosthesis: With emphasis on the genesis of the Austin-Flint murmur, Circulation 51:402, 1975.
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