Annotations

I support such a blunting or blocking effect. It may be that one frequently is in an escalation race; each increase in diuresis may be met by a further increase in sodium intake. The two types of evidence which we have presented do not give completely solid evidence that increased salt appetite and sodium intake occurs in the diuretic-treated hypertensive patient. However, the adaptive changes to sodium deprivation in other species involves change to conserve sodium loss and to increase sodium intake and the results cited above suggest that humans also are resPonding to sodium depletion by increasing their sodium intake. The authorities who would deny the necessity of sodium restriction in the treated hypertensive may frequently be pragmatically correct; we suggest that this is a quantitative question. The variables probably include the patient's basal salt intake, the sensitivity of his blood pressure to salt deprivation, the amount t h a t the patient increases his salt intake, and the dose of diuretic that the physician is willing to prescribe. It seems likely that the behavioral change of ir~creased salt ingestion may at times defeat t h e therapeutic attempts of the physician, and that sodium restriction should remain part of the physician's advice to patients receiving diuretics for hypertension. If the patient is not responding well to minimal therapy then monitoring of the patient's 24 hour urine sodium excretion may help to guide the physician and patient to the correct therapy.

Herbert G. Langford, M.D., F.A.C.P. Robert L. Watson, D.V.M., Ph.D. Jeanne Gouras Thomas, M.S. Departments of Medicine and Preventive Medicine University of Mississippi Medical Center Jackson, Miss. 39216

REFERENCES

1. Ambard, L., and Beaujard, E.: Causes de l'hypertension arterielle, Arch. Gen. Med., Paris, 1:520, 1904. 2. Allen, F. M., and Sherrill, J.: The treatment of arterial hypertension, J. Metabol. Res. 2.'429, 1922. 3. Kempner, W.: Treatment of hypertensive vascular disease with rice diet, Am. J. Med 4:545, 1948. 4. Kincaid-Smith, P., McDonald, I., Hua, A., Laver, M. D., and Fank, P.: Changing concepts in the management of hypertension, Med. J. Aust. 1:327, 1975. 5. Editorial, Salt and hypertension, Lancet 1'.1325, 1975. 6. Denton, D. A.: Evolutionary aspects of the emergency of aldosterone secretion and salt appetite, Physiol. Rev. 45:245, 1965. 7. Langford, H. G., and Watson, R. L.: Electrolytes and hypertension in epidemiology and control of hypertension, edited by O. Paul, Miami, 1975, Symposium Specialists, pp. 119-130. 8. Lambert, B. A., and Kuhlback, G.: Effect of chlorthiazide and hydrochlorthiazide on the excretion of calcium in urine, Scand. J. Clin. Lab. Invest. 1 1:351, 1959. 9. Yenson, R.: Some factors affecting taste sensitivity in man: II. Depletion of body salt, Q. J. Exp. Psychol. 11:230, 1959. 10. Henkin, R. I., Gill J. R., Jr., and Bartter, F. C.: Studies of taste thresholds in normal man and in patients with adrenal corticoid insufficiency: The role of adrerial cortical steroids and of serum sodium concentration, J. Clin. Invest. 42:727, 1963. 11. Parijs, J., Joosens, J. V., Van der Linden, L., Verstreken, G., and Amery, A. K. P. C.: Moderate sodium restriction and diuretics in the treatment of hypertension, AM. HEART J. 85:22, 1973. 12. Fallis, N., and Ford, R. V.: Electrolyte excretion and hypertension response, J. A. M. A. 176:581, 1961. 13. Winer, B. M.: The antihypertensive actions ofbenzothiadiazines, Circulation 23:211, 1961.

Proper management of acute coronary insufficiency--the burden of proof

There is much enthusiasm now for urgent coronary bypass surgery as the proper therapeutic approach to patients with acute coronary insufficiency. The popularity of this attitude rests on three principal supports, whose validity should be questioned. These are: (1) a conviction that medical therapy is ineffective, (2) a surgical mortality rate that is referred to as "small" in comparison to the peril of withholding surgery, and (3) a bias that, given a threatening situation, vigorous action is inherently superior to an (apparently) less dramatic strategy. The study by Gazes and associates ~ presented a grim outlook for patients with acute coronary insufficiency: e.g., 21 per cent experienced a myocardial infarct and 9 per cent died within three months,, and the prognosis was even worse in the subgroup of patients with continued bouts of chest pain after hospitalization. Those data helped to establish a receptive mood for a fresh therapeutic approach, and they still often are quoted as the medical treatment results against which surgery

532

is to be compared. The patients, however, were treated prior to the use of propranolol, and the data can no longer be considered representative of medical therapy. Present methods of intensive medical therapy, including propranolol administration, sUcceed in resolving the acute illness in the great majority of patients. ~ The group of patients treated medically sometimes includes those rejected from surgery because of poor myocardial function or other reasons which themselves influence prognosis adversely. This is another factor which has unfavorably misrepresented the outcome of medical treatment. When a more homogeneous group, comprised only of surgically acceptable patients, was randomly allocated to medical or surgical treatment, the incidences of death and myocardial infarction were comparatively low in medical patients. 3 How effective is urgent coronary bypass in preventing threatened infarction or death? Detection of intraoperative myocardial infarction is fallible, but its incidence certainly is

April, 1977, Vol. 93, No. 4

Annotations

substantial. T h e average operative m o r t a l i t y rate of p u b l i s h e d reports is n e a r 10 per cent. As with medical t h e r a p y , however, t h e success rate is improving, a n d in at least s o m e medical centers t h e p r e s e n t m o r t a l i t y rate is clearly less t h a n 10 per cent. B u t regardless of t h e absolute n u m b e r s a n d t h e varied success of p a r t i c u l a r medical centers, t h e risk of u r g e n t b y p a s s in p a t i e n t s a c u t e l y ill with coronary insufficiency is a l m o s t certainly greater t h a n t h e risk of s c h e d u l e d elective b y p a s s in stable patients. Therefore, if it is possible w i t h o u t d e a t h or p e r m a n e n t loss of m y o c a r d i a l tissue, stabilization of t h e pat i e n t would seem preferable, especially in hospitals less a c c u s t o m e d to mobilization u n d e r e m e r g e n c y conditions in off hours. A m a j o r difficulty is t h e fact t h a t t h e r e are n o t a n d n e v e r will be a n y single values for t h e incidence of m y o c a r d i a l infarction or of d e a t h from either form of t h e r a p y . T h e best information we can expect to possess is the i m m e d i a t e past experience of a specific medical center w i t h a defined t y p e of patient. T h e prognosis d e p e n d s very m u c h on t h e definition of the s y n d r o m e or t h e " s u b g r o u p " of p a t i e n t s u n d e r consideration. 1"~ For t h a t reason a n d others, c o m p a r m o n of r e s u l t s from different studies will c o n t i n u e to be f r u s t r a t i n g l y inconclusive. T h e m o s t productive a p p r o a c h would seem to be to define t h e particular p a t i e n t population u n d e r s t u d y a n d to s e p a r a t e this population into t r e a t m e n t groups which are t r u l y c o m p a r a b l e at t h e onset. T h e i m p o r t a n c e of t h e s e s t e p s h a s been recograzed for s o m e time. ~ T h e optimal m e t h o d of achieving comparability is by r a n d o m allocation of p a t i e n t s lafter each is deemed surgically acceptable). E v e n t h e n t h e conclusions m a y pertain with c e r t a i n t y only to the medical center a n d t h e p a t i e n t population involved. Hopefully. t h e results of several different r a n d o m i z e d studies will be c o n s i s t e n t e n o u g h to be combined. T h e conclusions t h e n could be applied broadly with even greater confidence t h a n in t h e case of a single large study. In t h e m e a n t i m e , t h e following a p p r o a c h to t h e m a n a g e m e n t of p a t i e n t s with a c u t e coronary insufficiency would be consistent with t h e information now available. T h i s p l a n is n o t advocated as necessarily better t h a n performing c o r o n a r y bypass u r g e n t l y on all patients. It simply is one a l t e r n a t i v e t h a t is at least equally justifiable on t h e basis of existing data. *"This question (of efficacy) can be satisfactorily settled only by instituting, in a large number of cases, which are well identified and nearly similar, a fair experimental comparison of the different active and expectant modes of practice... -5

T h e p a t i e n t is p u t to bed in a n I n t e n s i v e Care Unit. Propranolol is used or n o t used d e p e n d i n g u p o n t h e severity of angina prior to hospitalization, as well as u p o n o t h e r clinical considerations. M a n y p a t i e n t s will h a v e no f u r t h e r s y m p t o m s after hospitalization, a n d m o s t others c a n be stabilized by propranolol. Only a small fraction of p a t i e n t s will c o n t i n u e to have a n g i n a a n d ischemic E C G c h a n g e s despite several days of intensive medical therapy. T h e y are t h e only ones in w h o m coronary b y p a s s surgery is carried o u t on a n u r g e n t basis (while r a t h e r a b r u p t l y decreasing their propranolol dose). T h e other patients, who were successfully stabilized in t h e I n t e n sive Care Unit. are progressively a m b u l a t e d over a period of several d a y s a n d are discharged from t h e hospital in two to three weeks. Some will m a i n t a i n a satisfactory s y m p t o m a t i c state on continued medical t r e a t m e n ~ In one s m a l l experience. b y p a s s surgery was t h u s avoided in a p p r o x i m a t e l y h a l f of t h e p a t i e n t s / O t h e r patients who initially stablizied in t h e hospital can be expected to develop i n c a p a c i t a t i n g exertional angina following discharge. Elective surgery is r e c o m m e n d e d in these patients because of its d e m o n s t r a t e d effectiveness in relief of disabling angina.

William A. Neill, M.D. Chief of Cardiology Veterans Administration Hospital 150 South Huntington Ave. Boston, Mass. 02130

REFERENCES

1.

2.

3.

4.

5.

Gazes. P C.. Mobley, E. M.. Jr.. a n d Faris, H. M., Jr.: Preinfarction (unstable ~a n g i n a : a prospective s t u d y : t e n year follow-up; prognostic significance of electrocardiographic changes, Circulation 48:331, 1973. Fischl. S. J.. H e r m a n . M. V.. a n d Gorlin, R.: T h e i n t e r m e d i a t e coronary s y n d r o m e : clinical, angiographic a n d t h e r a p e u t i c aspects. N. Engl. J. Med. 288:1193, 1973. Selden. R.. Neill. W. A.. R i t z m a n n , L. W., Okies, J. E., a n d Anderson. R. P.: Medical versus surgical t h e r a p y for a c u t e coronary insufficiency: a r a n d o m i z e d study, N. Engl. J. Med. 293'.1329, 1975. K r a u s s , K. R., H u t t e r , A. M., Jr., a n d DeSanctis, R. W.: A c u t e coronary insufficiency: course a n d follow-up, Circulation 4 5 (Suppl. 1):66, 1972. Bigelow, J.: N a t u r e in disease, Boston, 1854, T i c k n o r a n d Fields, p. 33.

Augmentation of auscultatory and echocardiographic mitral valve prolapse by atrial premature depolarizations

T h e mid-systolic click-late systolic m u r m u r prolapsing A-V valve s y n d r o m e h a s been t h e focus of increasing a t t e n t i o n in t h e p a s t decade a n d h a s recently been reviewed by Barlow a n d

American Heart Journal

Pocock. 1 Several physiological a n d pharmacological interventions h a v e been described w h i c h are capable of intensifying a n d / o r prolonging t h e m u r m u r . 1-~ A l t h o u g h t h e m e c h a n i s m s

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Proper management of acute coronary insufficiency--the burden of proof.

Annotations I support such a blunting or blocking effect. It may be that one frequently is in an escalation race; each increase in diuresis may be me...
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