JACC
Vol. t5. No. 1 January1990:91-3
91
severe cardiac s
fictive variant o
e left ventricle (I ,2,5,6).
interest since its Sakamoto et al. (7) a
g I I% of all patients wit ings (7-9). For example, the cha
bliag a “spade” (i.e., the playing reflecting the localized apical rtropby)--are clinical features not often observed in nts with by~e~rophic cardiomyopathy who arc ident in other parts of the world (2,3). The rca expression of apical
*Editorials published in Jo~rrnalof tlte American CoNege of Cardiology reflectthe views of the authors and do not necessarily represent the viewsof JACCor the American Collegeof Cardiology. From the Echocardiography Laboratory. National Heart, Lung, and Blood Institute. National Institutes of Health. Btl‘resda. Mwfland. : Barry J. Maron, Mb, National~lnstiktesof Health. Building 10, Room 7Bl5. Bethesda, Maryland 20892. 81990 by the American Collegeof Cardiology
by~e~ro~b~c catdiomyo~athy and the number of s that have been published on this particular subset of atients are d~spropo~io~ate, considering that in most parts f the world it is an exceedingly rare man~es~tion of a generally uncommon disease. In this issue of the Journal, Webb et al. (24)from Toronto General Hospital present t t recent contribution to our knowledge of patients w ertropbic cardiomyopathy
as~n~~tomaticover the 1 to 22 year (average 7) period of follow-up; none had died. Indeed, although sudden cardiac death has been reported occasionally in non-Asians with 0735~lo97/90/$3.50
92
hypertrophic cardiomyopathy (!3), it appears to be exceedingly uncommon in these patients. A!tho:Jgh other centers have reported patients with the apica! form of hypertrophic cardiomyopathy who developed important symptoms of functional limitation, the “benign” clinical course described by Webb et a!. (24) is, nevertheless, consistent with the experience reported from Japan. One of the patients described by Webb et a!. (24) experienced an apical myocardia! infarction and the development of a discrete apicalaneurysm (13)in association with 10~sof “giant” T wave negativity and potentially lethal ventricular arrhythmias. Although only an anecdotal observation at this time, such a finding suggests an interesting and potentially important facet of the natural history of hypertrophic cardiomyopathy that may be unique to patients with apical hypertropt y. Relation of apical hypertrophy to the overall population of hypertrophic cardiomyopathy. There is ample reason to believe that apical hypertrophy (in non-Asian patients) does not constitute a separate disease entity, but rather represents a form of nonobstructive hypertrophic cardiomyopathy, and is part of the broad clinical and morphologic spectrum of this disease (2,3,13,14).Indeed, typical of other forms of hypertrophic cardiomyopathy (29, apical hypertrophic cardiomyopathy may be transmitted genetically, with first degree relatives demonstrating either apical or a variety of nonapica! patterns of left ventricular hypertrophy (13,14). Much of the confusion and disagreement regarding the definition and diagnosis of apical hypertrophic cardiomyopathy may be due to differences among investigators and institutions with regard to the selection of patients (i.e., patterns of patient referral) and also the precise morphologic definition of this entity. For example, in its purest morphologic form, apical hypertrophy is relatively mild in extent and is confined to the most distal portion of left ventricle, well below papillary muscle level-i.e., similar to the original anatomic description of apical hypertrophic cardiomyopathy by Sakamoto et al. (7). Consequently, in practical terms, the localized hypertrophy in such patients would be imaged by two-dimensional echocardiography only in the apical views, and not in the parasteraal short- and long-axis planes. On the basis of published data, as well as my own experience, this “pure” morphologicform (“apical hypertrophyof the Japanese type”) would appear to be exceeding!y rare in non-Asians and, even when observed, it is not invariably associated with “giant” T wave inversion(13,14). Indeed, most of the cases reported as examples of apica! hypertrophiccardiomyopathy from outside Japan (including those of Webb et a!. (24))are characterized by hypertrophy that extends, to some degree, beyond the true left ventricu!arapex and more extensively involvesotherportionsof the distal left ventricle and even occasionally small localized resions of the basal ventricle (13). Because there is no standard,precise morphologic definition of “apical hyperapical
JACC Vol. 15. No. I January 1 91-3
MARON EDITORIAL COMMENT
trophic cardiomyopathy,” investigators have natMra!~ydiffered with respect to their perceptions of this disease entity, comributing to the confusion regarding its nature, clinical significance and relation to the disease spectrum of bypertrophic cardiomyopathy. Conclusions. The present report of Webb et a!. (24) extends the overall clinical experience and knowledge of apical hypertrophic cardiomyopathy in non-Asian patients, particularly with respect to the natural history of this entity. The authors’ findings emphasize that many, but not al!, patients constituting this rare subset within the disease spectrum of hypertrophic cardiomyopathy experience a benign clinical course and may remain in relatively stable condition without symptoms for long periods of time.
ces I. Maron
BJ. Gottdiener JS. Epstein SE. Patterns and significance of distribution of left ventricular hypertrophy in hypertrophic cardiomyop athy: a wide-angle, two-dimensional echocardiographic study of 125 patients. Am 3 Cardiol 1981;48:418-28.
2. Maron BJ. Bonow RO. Cannon RO, Leon MB, Epstein SE. Hypenrophic cardiomyopathy: interrelation of clinical manifestations, pathophysiology. and therapy. N Engl J Med 1987;316:780-9 and 844-52. 3. Wigle ED, Sasson 2, Henderson MA, et al. Hypertrophic cardiomyopathy: the importance of the site and the extent of hypertrophy: a review. hog Cardiovasc Dis 1985;28:1-83. 4. Shapiro LM. McKenna WJ. Distribution of left ventricular hypertrophy in hypertrophic cardiomyopathy: a two-dimensional echocardiographic study. J Am Coil Cardiol 1983;2:437-44. 5. Cir6 E. Nichols PF. Maron BJ. Heterogeneous morphologic expression of genetically transmitted hypertrophic cardiomyopathy: two-dimensional echocardiographic analysis. Circulation 1983:67:1227-33. 6. Spirit0 P. Maron BJ, Bonow RO, Epstein SE. Severe functional limitation in patients with hypertrophic cardiomyopathy and only mild localized left ventricular hypenrophy. J Am Coil Cardiol 1986;8:537-44. 7. Sakamoto T, Tei C, Murayama M, lchiyasu H, Hada Y. Giant T wave inversion as a manifestation of asymmetrical apical hypertrophy (AAH) of the left ventricle: echocardiographic and ultmsono-cardiotomographic study. Jpn Heart J 1976:17:61 l-29. 8. Yamaguchi H, lshimura T, Nishiyama S, et al. Hyprtrophic nonobstructive cardiomyopathy with giant negative T waves (apical hypertrophy): ventriculographic and echocardiographic features in 30 patients. Am J Cardiol 1979;44:401-12. 9. Sakamoto T, Amano K, Hada Y. et al. Asymmetric apical hypertrophy: ten years’ experience. Postgrad Med J 1986;62:567-70. IO. Koga Y. Baya K, Toshima H. Prognosis in hypertrophic Am Heart J 1984;108:351-9. It.
cardiomyopathy.
Fujii J. Saibara S, Sawada H, Aixawa T, Kato K. Distribution of left ventricular hypertrophy and e!ectrocardiographic findings in patients with so-called apical hypertrophic cardiomyopa:hy. J Cardiogr 1985;IS(suppl VI):VI-23-33.
12. Koga Y, Itaya M, Takahashi H, et al. Apical hypertrophy and its genetic and acquired factors. J Cardiogr 1985;15(suppl VI):VI-65-74. 13. Maron BJ, Bonow RO, Seshagiri TNR, Roberts WC, Epstein SE. Hypettrophic cardiomyopathy with ventricular septal hypertrophy localized to the apical region of the left ventricle (apical ~y~~ro~b~c cardiomyopathy). Am J Cardiol 1982;49:1838-48. 14. Louie EK. Maron BJ. Apical hypertrophic cardiomyopathy: clinical and two-dimensional echocardiographic assessment. Ann Intern Med 1987;
lofK663-70.
exesske X4-8. 1~2~~~:~~5-9. PY. Lab?~~che JM. Thieulewn
18.
apathy: clinicai and rne~~bo~~c stu
inapical
~y~~r~~o~~~s cardiomyopathy.
Am 3
R. LPorenie C. Casio FG. Familial apical Am J Cardiol ~~~~;~2:~2~-2, owski I-l, Liu P, Wig!e follow-~~ and diagnos
Apical Rypertrophic orrelates. J Am Coil
nd diagnosis of apical hy
19. 20. cardiomyopathy.
Am Heart J 1983:105:855-6.
inheritance in byps~rophic ea~d~omyopathy: assessment by M-mode and t~~d~rne~s~o~a~ ec~~~~~iQ~r~~~y. Am J Cardio0 ~9~4;53~~~~~-~4.
Vol. t5. No. 1 January1990:91-3
91
severe cardiac s
fictive variant o
e left ventricle (I ,2,5,6).
interest since its Sakamoto et al. (7) a
g I I% of all patients wit ings (7-9). For example, the cha
bliag a “spade” (i.e., the playing reflecting the localized apical rtropby)--are clinical features not often observed in nts with by~e~rophic cardiomyopathy who arc ident in other parts of the world (2,3). The rca expression of apical
*Editorials published in Jo~rrnalof tlte American CoNege of Cardiology reflectthe views of the authors and do not necessarily represent the viewsof JACCor the American Collegeof Cardiology. From the Echocardiography Laboratory. National Heart, Lung, and Blood Institute. National Institutes of Health. Btl‘resda. Mwfland. : Barry J. Maron, Mb, National~lnstiktesof Health. Building 10, Room 7Bl5. Bethesda, Maryland 20892. 81990 by the American Collegeof Cardiology
by~e~ro~b~c catdiomyo~athy and the number of s that have been published on this particular subset of atients are d~spropo~io~ate, considering that in most parts f the world it is an exceedingly rare man~es~tion of a generally uncommon disease. In this issue of the Journal, Webb et al. (24)from Toronto General Hospital present t t recent contribution to our knowledge of patients w ertropbic cardiomyopathy
as~n~~tomaticover the 1 to 22 year (average 7) period of follow-up; none had died. Indeed, although sudden cardiac death has been reported occasionally in non-Asians with 0735~lo97/90/$3.50
92
hypertrophic cardiomyopathy (!3), it appears to be exceedingly uncommon in these patients. A!tho:Jgh other centers have reported patients with the apica! form of hypertrophic cardiomyopathy who developed important symptoms of functional limitation, the “benign” clinical course described by Webb et a!. (24) is, nevertheless, consistent with the experience reported from Japan. One of the patients described by Webb et a!. (24) experienced an apical myocardia! infarction and the development of a discrete apicalaneurysm (13)in association with 10~sof “giant” T wave negativity and potentially lethal ventricular arrhythmias. Although only an anecdotal observation at this time, such a finding suggests an interesting and potentially important facet of the natural history of hypertrophic cardiomyopathy that may be unique to patients with apical hypertropt y. Relation of apical hypertrophy to the overall population of hypertrophic cardiomyopathy. There is ample reason to believe that apical hypertrophy (in non-Asian patients) does not constitute a separate disease entity, but rather represents a form of nonobstructive hypertrophic cardiomyopathy, and is part of the broad clinical and morphologic spectrum of this disease (2,3,13,14).Indeed, typical of other forms of hypertrophic cardiomyopathy (29, apical hypertrophic cardiomyopathy may be transmitted genetically, with first degree relatives demonstrating either apical or a variety of nonapica! patterns of left ventricular hypertrophy (13,14). Much of the confusion and disagreement regarding the definition and diagnosis of apical hypertrophic cardiomyopathy may be due to differences among investigators and institutions with regard to the selection of patients (i.e., patterns of patient referral) and also the precise morphologic definition of this entity. For example, in its purest morphologic form, apical hypertrophy is relatively mild in extent and is confined to the most distal portion of left ventricle, well below papillary muscle level-i.e., similar to the original anatomic description of apical hypertrophic cardiomyopathy by Sakamoto et al. (7). Consequently, in practical terms, the localized hypertrophy in such patients would be imaged by two-dimensional echocardiography only in the apical views, and not in the parasteraal short- and long-axis planes. On the basis of published data, as well as my own experience, this “pure” morphologicform (“apical hypertrophyof the Japanese type”) would appear to be exceeding!y rare in non-Asians and, even when observed, it is not invariably associated with “giant” T wave inversion(13,14). Indeed, most of the cases reported as examples of apica! hypertrophiccardiomyopathy from outside Japan (including those of Webb et a!. (24))are characterized by hypertrophy that extends, to some degree, beyond the true left ventricu!arapex and more extensively involvesotherportionsof the distal left ventricle and even occasionally small localized resions of the basal ventricle (13). Because there is no standard,precise morphologic definition of “apical hyperapical
JACC Vol. 15. No. I January 1 91-3
MARON EDITORIAL COMMENT
trophic cardiomyopathy,” investigators have natMra!~ydiffered with respect to their perceptions of this disease entity, comributing to the confusion regarding its nature, clinical significance and relation to the disease spectrum of bypertrophic cardiomyopathy. Conclusions. The present report of Webb et a!. (24) extends the overall clinical experience and knowledge of apical hypertrophic cardiomyopathy in non-Asian patients, particularly with respect to the natural history of this entity. The authors’ findings emphasize that many, but not al!, patients constituting this rare subset within the disease spectrum of hypertrophic cardiomyopathy experience a benign clinical course and may remain in relatively stable condition without symptoms for long periods of time.
ces I. Maron
BJ. Gottdiener JS. Epstein SE. Patterns and significance of distribution of left ventricular hypertrophy in hypertrophic cardiomyop athy: a wide-angle, two-dimensional echocardiographic study of 125 patients. Am 3 Cardiol 1981;48:418-28.
2. Maron BJ. Bonow RO. Cannon RO, Leon MB, Epstein SE. Hypenrophic cardiomyopathy: interrelation of clinical manifestations, pathophysiology. and therapy. N Engl J Med 1987;316:780-9 and 844-52. 3. Wigle ED, Sasson 2, Henderson MA, et al. Hypertrophic cardiomyopathy: the importance of the site and the extent of hypertrophy: a review. hog Cardiovasc Dis 1985;28:1-83. 4. Shapiro LM. McKenna WJ. Distribution of left ventricular hypertrophy in hypertrophic cardiomyopathy: a two-dimensional echocardiographic study. J Am Coil Cardiol 1983;2:437-44. 5. Cir6 E. Nichols PF. Maron BJ. Heterogeneous morphologic expression of genetically transmitted hypertrophic cardiomyopathy: two-dimensional echocardiographic analysis. Circulation 1983:67:1227-33. 6. Spirit0 P. Maron BJ, Bonow RO, Epstein SE. Severe functional limitation in patients with hypertrophic cardiomyopathy and only mild localized left ventricular hypenrophy. J Am Coil Cardiol 1986;8:537-44. 7. Sakamoto T, Tei C, Murayama M, lchiyasu H, Hada Y. Giant T wave inversion as a manifestation of asymmetrical apical hypertrophy (AAH) of the left ventricle: echocardiographic and ultmsono-cardiotomographic study. Jpn Heart J 1976:17:61 l-29. 8. Yamaguchi H, lshimura T, Nishiyama S, et al. Hyprtrophic nonobstructive cardiomyopathy with giant negative T waves (apical hypertrophy): ventriculographic and echocardiographic features in 30 patients. Am J Cardiol 1979;44:401-12. 9. Sakamoto T, Amano K, Hada Y. et al. Asymmetric apical hypertrophy: ten years’ experience. Postgrad Med J 1986;62:567-70. IO. Koga Y. Baya K, Toshima H. Prognosis in hypertrophic Am Heart J 1984;108:351-9. It.
cardiomyopathy.
Fujii J. Saibara S, Sawada H, Aixawa T, Kato K. Distribution of left ventricular hypertrophy and e!ectrocardiographic findings in patients with so-called apical hypertrophic cardiomyopa:hy. J Cardiogr 1985;IS(suppl VI):VI-23-33.
12. Koga Y, Itaya M, Takahashi H, et al. Apical hypertrophy and its genetic and acquired factors. J Cardiogr 1985;15(suppl VI):VI-65-74. 13. Maron BJ, Bonow RO, Seshagiri TNR, Roberts WC, Epstein SE. Hypettrophic cardiomyopathy with ventricular septal hypertrophy localized to the apical region of the left ventricle (apical ~y~~ro~b~c cardiomyopathy). Am J Cardiol 1982;49:1838-48. 14. Louie EK. Maron BJ. Apical hypertrophic cardiomyopathy: clinical and two-dimensional echocardiographic assessment. Ann Intern Med 1987;
lofK663-70.
exesske X4-8. 1~2~~~:~~5-9. PY. Lab?~~che JM. Thieulewn
18.
apathy: clinicai and rne~~bo~~c stu
inapical
~y~~r~~o~~~s cardiomyopathy.
Am 3
R. LPorenie C. Casio FG. Familial apical Am J Cardiol ~~~~;~2:~2~-2, owski I-l, Liu P, Wig!e follow-~~ and diagnos
Apical Rypertrophic orrelates. J Am Coil
nd diagnosis of apical hy
19. 20. cardiomyopathy.
Am Heart J 1983:105:855-6.
inheritance in byps~rophic ea~d~omyopathy: assessment by M-mode and t~~d~rne~s~o~a~ ec~~~~~iQ~r~~~y. Am J Cardio0 ~9~4;53~~~~~-~4.
