LETTERS TO THE EDITOR
in 32 percent of their patients with a mean age of 71 years. This is an extremely high figure and certainly greater than that which has been recognized in published reports to this date. Unfortunately, the authors do not indicate whether these diagnoses were confirmed by catheterization and appropriate angiographic studies. Responding to their final point, we do not intend to convey the impression that it is appropriate to pursue aggressively the diagnosis of idiopathic hypertrophic subaortic stenosis in all patiepts with mitral anular calcification or that other causes of mitral anular calcification do not exist. However, echocardiographic demonstration of mitral anular calcification should prompt careful evaluation of this study for evidence of idiopathic hypertrophic subaortic stenosis. Coexistent clinical findings, electrocardiographic abnormalities or roentgenographic changes may then influence the need for further investigation. ltzhak Kronzon, MD Echocardiographic Laboratory Ephraim Glassman, MD, FACC Cardiac Catheterization Laboratory New York University Hospital New York, New York
ECHOCARDIOGRAM IN IDIOPATHIC HYPERTROPHIC SUBAORTIC STENOSIS
The experience in our ecnocardiography laboratory has been in agreement with the findings reported by Krajcer et al.‘-i.e., that mid systolic closure of the aortic valve in patients with idiopathic hypertrophic subaortic stenosis has always been associated with a resting outflow tract gradient. However, since their article was published, a 53 year old black woman had an echocardiogram performed as part of a preoperative cardiovascular evaluation prior to an otolaryngologic procedure. Onauscultation the patient had a grade 3/S holosystolic apical murmur that did not change significantly with various physiologic maneuvers. The echocardiogram (Fig. 1) revealed asymmetric septal hypertrophy, a calcified mitral anulus and mid systolic closure of the aortic valve. Cardiac catheterization at a later date revealed no resting left ventricular outflow tract gradient, but did reveal provokable gradients of 52 mm Hg with the Valsalva maneuver, 18 mm Hg with amyl nitrite inhalation and 70 mm Hg with the first beat after a premature ventricular complex. The echocardiogram was repeated at the time of cardiac catheterization and the findings were identical with those before cath&erization. Left ventricular angiography confirmed the presence of the calcified mitral anulus but did not revealmitral ‘insufficiency. We conclude that although mid systolic closure of the aortic valve in’ idiopathic hypertrophic subaortic stenosis usually indicates the presence of a’resting outflow tract gradient, there are exceptions to this observation. Charles Kanakis, MD Cardiology Section The Abraham Lincoln School of Medicine Chicago, Illinois Reference 1.
Krajcer 2, Oman F, Pechscok LW. Garcia E, Leachman RD: Early systolic cbswe of the aortic valve in patients with hypertrophic wbaortic stenosis and discrete subawtlc stenosis: correlation wlm preoperative and postoperative hemodynambs. Am J C&b1 41X323-829. 1979
580
September 1979
The American Journal of CARDIOLOGY
FfGURE 1. E#hocardiogams. Top, afmws indicate mki Systolic closure of right arxtic valve leaflet. Bottom, IVS = intraventricular septum; MA = mitral anubs (calcified).
REPLY
In our study, echocardiographic analysis of the aortic valve was ,performed in 35 consecutive patients with idiopathic hypertiophic subaortic stenosis. Since then an additional 45 patients with this condition have been examined in our laboratory. In every instance, mid systolic closure of the aortic valve has occurred only in patients with a significant gradient at rest (greater than 20 mm Hg). Other investigators1T2 have reported similar findings. Although the echocardiogram presented by Kanakis may be an exception to our observations, we believe that the incidence rate of such false positive findings is low. The case presented by Kanakis has several unusual features-not noted in any of our patients-that warrant further discussion. First, the murmur did not’change significantly with various physiologic maneuvers (presumably including the Valsalva maneuver), a rather atypical finding in provocable idiopathic hypertrophic subaortic stenosis. Second, the apparent lack of systolic anterior motion of the mitral valve also is somewhat unusual in a patient with provocable left ventricular outflow tract obstruction. Finally, the left atrium is obviously enlarged, although there was no cineangiographic evidence of mitral regurgitation, another reported cause of early systolic aortic valve closure.3 In the absence of atria1 fi-
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in 32 percent of their patients with a mean age of 71 years. This is an extremely high figure and certainly greater than that which has been recognized in published reports to this date. Unfortunately, the authors do not indicate whether these diagnoses were confirmed by catheterization and appropriate angiographic studies. Responding to their final point, we do not intend to convey the impression that it is appropriate to pursue aggressively the diagnosis of idiopathic hypertrophic subaortic stenosis in all patiepts with mitral anular calcification or that other causes of mitral anular calcification do not exist. However, echocardiographic demonstration of mitral anular calcification should prompt careful evaluation of this study for evidence of idiopathic hypertrophic subaortic stenosis. Coexistent clinical findings, electrocardiographic abnormalities or roentgenographic changes may then influence the need for further investigation. ltzhak Kronzon, MD Echocardiographic Laboratory Ephraim Glassman, MD, FACC Cardiac Catheterization Laboratory New York University Hospital New York, New York
ECHOCARDIOGRAM IN IDIOPATHIC HYPERTROPHIC SUBAORTIC STENOSIS
The experience in our ecnocardiography laboratory has been in agreement with the findings reported by Krajcer et al.‘-i.e., that mid systolic closure of the aortic valve in patients with idiopathic hypertrophic subaortic stenosis has always been associated with a resting outflow tract gradient. However, since their article was published, a 53 year old black woman had an echocardiogram performed as part of a preoperative cardiovascular evaluation prior to an otolaryngologic procedure. Onauscultation the patient had a grade 3/S holosystolic apical murmur that did not change significantly with various physiologic maneuvers. The echocardiogram (Fig. 1) revealed asymmetric septal hypertrophy, a calcified mitral anulus and mid systolic closure of the aortic valve. Cardiac catheterization at a later date revealed no resting left ventricular outflow tract gradient, but did reveal provokable gradients of 52 mm Hg with the Valsalva maneuver, 18 mm Hg with amyl nitrite inhalation and 70 mm Hg with the first beat after a premature ventricular complex. The echocardiogram was repeated at the time of cardiac catheterization and the findings were identical with those before cath&erization. Left ventricular angiography confirmed the presence of the calcified mitral anulus but did not revealmitral ‘insufficiency. We conclude that although mid systolic closure of the aortic valve in’ idiopathic hypertrophic subaortic stenosis usually indicates the presence of a’resting outflow tract gradient, there are exceptions to this observation. Charles Kanakis, MD Cardiology Section The Abraham Lincoln School of Medicine Chicago, Illinois Reference 1.
Krajcer 2, Oman F, Pechscok LW. Garcia E, Leachman RD: Early systolic cbswe of the aortic valve in patients with hypertrophic wbaortic stenosis and discrete subawtlc stenosis: correlation wlm preoperative and postoperative hemodynambs. Am J C&b1 41X323-829. 1979
580
September 1979
The American Journal of CARDIOLOGY
FfGURE 1. E#hocardiogams. Top, afmws indicate mki Systolic closure of right arxtic valve leaflet. Bottom, IVS = intraventricular septum; MA = mitral anubs (calcified).
REPLY
In our study, echocardiographic analysis of the aortic valve was ,performed in 35 consecutive patients with idiopathic hypertiophic subaortic stenosis. Since then an additional 45 patients with this condition have been examined in our laboratory. In every instance, mid systolic closure of the aortic valve has occurred only in patients with a significant gradient at rest (greater than 20 mm Hg). Other investigators1T2 have reported similar findings. Although the echocardiogram presented by Kanakis may be an exception to our observations, we believe that the incidence rate of such false positive findings is low. The case presented by Kanakis has several unusual features-not noted in any of our patients-that warrant further discussion. First, the murmur did not’change significantly with various physiologic maneuvers (presumably including the Valsalva maneuver), a rather atypical finding in provocable idiopathic hypertrophic subaortic stenosis. Second, the apparent lack of systolic anterior motion of the mitral valve also is somewhat unusual in a patient with provocable left ventricular outflow tract obstruction. Finally, the left atrium is obviously enlarged, although there was no cineangiographic evidence of mitral regurgitation, another reported cause of early systolic aortic valve closure.3 In the absence of atria1 fi-
Volume 44
