Prognosis and mortality of hypertrophic obstructive cardiomyopathy

Mode of inheritance of hypertrophic cardiomyopathy in Iceland. Echocardiographic study

We used an abnormally thick interventricular septum (greater than or equal to 1.3 cm) as an echocardiographic marker to find the inheritance pattern of hypertrophic cardiomyopathy among relatives of eight patients who had that disease at necropsy. Forty normal subjects served as a control group. Fifty-eight family members were examined and 18 (41%) of the 44 first degree relatives had hypertrophic cardiomyopathy. The overall inheritance pattern was consistent with an autosomal dominant genetic disorder and in one family a recessive trait could be excluded. The diagnosis of hypertrophic cardiomyopathy can be difficult clinically as only 13% of our patients had serious symptoms and only 30% had abnormal auscultatory findings. The electrocardiogram is a useful screening test among relatives as it was abnormal in 20 (87%) of those who had an abnormally thick septum. Symmetric septal hypertrophy was found in 30% of patients with cardiomyopathy in this study and only 17% had clinical evidence of obstruction.

Syncope in hypertrophic cardiomyopathy

A patient with hypertrophic cardiomyopathy, syncope, and frequent ventricular tachycardia was monitored during a syncopal episode. An unrecordable blood pressure and the loss of a left ventricular outflow tract murmur without evidence of arrhythmia suggested a primary haemodynamic mechanism such as reduction in left ventricular volume.

Hypertrophic cardiomyopathy in infants: clinical features and natural history

The clinical and morphologic features of hypertrophic cardiomyopathy in 20 patients recognized as having cardiac disease in the first year of life are described. Fourteen of these 20 infants were initially suspected of having heart disease solely because a heart murmur was identified. However, the infants showed a variety of clinical findings, including signs of marked congestive heart failure (in the presence of non-dilated ventricular cavities and normal or increased left ventricular contractility) and substantial cardiac enlargement on chest radiograph. Other findings were markedly different from those usually present in older children and adults with hypertrophic cardiomyopathy (e.g., right ventricular hypertrophy on the ECG and cyanosis). Consequently, in 14 infants, the initial clinical diagnosis was congenital cardiac malformation other than hypertrophic cardiomyopathy. Twelve of the 14 infants who underwent left-heart catheterization showed substantial obstruction to left ventricular outflow (peak systolic pressure gradient greater than or equal to 35 mm Hg). However, unlike older patients with hypertrophic cardiomyopathy, infants with this condition commonly had marked obstruction to right ventricular outflow (35-106 mm Hg) (nine patients); in six patients, the magnitude of obstruction to right ventricular outflow was at least as great as that to left ventricular outflow. Asymmetric hypertrophy of the ventricular septum relative to the left ventricular free wall was present in the 16 patients who had echocardiographic or necropsy examination. Ventricular septal thickening was substantial in patients studied both before and after 6 months of age (mean 16 mm), indicating that in patients with hypertrophic cardiomyopathy, marked left ventricular hypertrophy may be present early in life and is probably congenital. The clinical course was variable in these patients, but the onset of marked congestive heart failure in the first year of life appeared to be an unfavorable prognostic sign; nine of the 11 infants with congestive heart failure died within the first year of life. In infants with hypertrophic cardiomyopathy, unlike older children and adults with this condition, sudden death was less common (two patients) than death due to progressive congestive heart failure.

Aortic regurgitation first appearing 12 years after successful septal myectomy for hypertrophic obstructive cardiomyopathy

Substantial aortic regurgitation developed in a patient with hypertrophic (obstructive) cardiomyopathy (HCM) who underwent septal myectomy. It was first noted 12 years after surgery. There was no evidence for surgical damage to the valve, subacute bacterial endocarditis, coexisting discrete subaortic stenosis or any other known etiology of aortic incompetence. This experience suggests that aortic regurgitation occasionally may be a late mode of deterioration in surgically treated patients with hypertrophic cardiomyopathy. Possible mechanisms for the development of aortic incompetence in such patients are discussed.

Surgical treatment of hypertrophic obstructive cardiomyopathy in the elderly

Three elderly patients with hypertropic obstructive cardiomyopathy which was successfully treated by surgery are described. The role of surgery in the management of older patients with this condition is discussed.

Arrhythmia in hypertrophic cardiomyopathy. I: Influence on prognosis

In order to examine the association between arrhythmia and subsequent prognosis, 72-hour ambulatory electrocardiographic monitoring was performed in 86 unselected patients with hypertrophic cardiomyopathy. During monitoring 23 patients experienced at least one episode of supraventricular tachycardia and 24 had ventricular tachycardia (of whom 10 had more than three episodes). The patients were then followed for a mean of 2.6 years (range one to four). Seven patients died suddenly. Of these, five had exhibited multiform and paired ventricular extrasystoles and ventricular tachycardia. These arrhythmias were significantly associated with sudden death whereas supraventricular arrhythmias were not. The patients who died suddenly were older and had experienced more symptoms than the survivors, and three had a family history of hypertrophic cardiomyopathy and sudden death. This experience provides the basis for the assessment of treatment in patients with hypertrophic cardiomyopathy and serious ventricular arrhythmia.

Prognostic significance of 24 hour ambulatory electrocardiographic monitoring in patients with hypertrophic cardiomyopathy: a prospective study

The prevalence and prognostic significance of ventricular arrhythmias identified on 24 hour ambulatory electrocardiographic monitoring was prospectively assessed in 99 patients with hypertrophic cardiomyopathy. In the absence of antiarrhythmic therapy, high grade ventricular arrhythmias (grade 3 and above) were common; that is they were identified in 66 percent of the patients, including 19 percent with episodes of asymptomatic ventricular tachycardia. Clinical outcome was assessed 3 years after the initial 24 hour ambulatory electrocardiogram. Of the 84 patients who did not undergo ventricular septal myotomy-myectomy, 6 died suddenly or experienced cardiac arrest, 1 died of progressive congestive heart failure and the other 77 have survived without a cardiac catastrophe. The prevalence rate of sudden death or cardiac arrest during the follow-up period was the same (3 percent) in patients with high grade arrhythmias other than ventricular tachycardia (1 of 37) as in those with no or low grade arrhythmias (1 of 29). However, the occurrence of a sudden cardiac catastrophe was significantly more common in patients with asymptomatic ventricular tachycardia of brief duration on 24 hour electrocardiography (4 [24 percent] of 17) than in patients without ventricular tachycardia (2 [3 percent] of 66) (p less than 0.02). In summary, (1) high grade ventricular arrhythmias are commonly found on continuous 24 hour electrocardiography monitoring in patients with hypertrophic cardiomyopathy; and (2) although sudden death is relatively uncommon in patients with high grade ventricular arrhythmias other than ventricular tachycardia (annual mortality rate 1 percent), the finding of ventricular tachycardia on 24 hour electrocardiography identifies a subgroup of patients at high risk for sudden death (annual mortality rate 8.6 percent). Although no conclusions can be drawn regarding the impact of therapy, our findings suggest that 24 hour electrocardiographic monitoring should be performed in patients with hypertrophic cardiomyopathy and that it may be reasonable to initiate antiarrhythmic therapy if ventricular tachycardia is identified.

Electron microscopic investigation of endomyocardial biopsy samples in hypertrophy and cardiomyopathy. A semiquantitative study in 48 patients

Electron microscopic and statistical analyses of 66 right ventricular biopsies from 48 patients were undertaken to investigate whether quantitative differences exist between those patients with "ordinary" myocardial hypertrophy and those suffering from a form of cardiomyopathy. The electron microscopic changes were scored and correlated with hemodynamic variables such as ejection fraction (EF), left ventricular end-diastolic pressure (LVEDP) and length of history. The patients were followed for an average of 22.5 months, permitting an assessment of prognosis. The results show that the three diagnostic groups--"ordinary" hypertrophy, hypertrophic cardiomyopathy (HOCM) and congestive cardiomyopathy (COCM)--overlap, but crossover of sarcomeres is more frequent in patients in whom HOCM is diagnosed. Except for a tenuous relationship between EF, and the electron microscopy (EM) (r = -0.46, p less than 0.1) and between LVEDP and EM score (r = 0.61, p less than 0.01), in the COCM group, no correlation could be established between EF, LVEDP and length of history when the patients were grouped according to histologic or clinical diagnosis. This study shows that the various claims regarding relationships between morphologic changes and the functional status of patients or prognosis cannot be confirmed.

Prognosis in hypertrophic cardiomyopathy: role of age and clinical, electrocardiographic and hemodynamic features

Retrospective analysis of the clinical course of 254 patients with hypertrophic cardiomyopathy, followed up for 1 to 23 years (mean 6), disclosed that 58 had died, 32 of them suddenly. The 196 survivors were compared with the 32 patients who died suddenly and with the 38 who died suddenly or with heart failure. The combination of young age (14 years or less), syncope at diagnosis, severe dyspnea at last follow-up and a family history of hypertrophic cardiomyopathy and sudden death best predicted sudden death (false negative rate 30 percent, false positive rate 27 percent). A "malignant" family history was associated with poor prognosis, particularly in the younger patients; a family history of hypertrophic cardiomyopathy without sudden death was more frequent in the survivors (12 percent) than in the dead (5 percent). Patients who had a diagnosis in childhood were usually asymptomatic, had an unfavorable family history and a 5.9 percent annual mortality rate. In those aged 15 to 45 years at diagnosis, there was a 2.5 percent annual mortality rate and syncope was the only prognostic feature. Among those diagnosed between age 45 and 60 years, dyspnea and exertional chest pain were more common in the patients who died, and the annual mortality rate was 2.6 percent. Poor prognosis was better predicted by the history at the time of diagnosis and by changes in symptoms during follow-up than by an electrocardiographic or hemodynamic measurement.

Echocardiographic differentiation of hypertensive heart disease and hypertrophic cardiomyopathy

The clinical differentiation of hypertensive heart disease from hypertrophic cardiomyopathy usually presents no problem but it is less clear whether an echocardiographic distinction can always be made and, if so, what those echocardiographic criteria of difference are. It can be inferred from recent publications that when echocardiographic criteria for hypertrophic cardiomyopathy are met in hypertensive subjects, both diagnoses may be made. This may be unjustified, and in order to clarify this problem that M-mode echocardiographic features of 37 patients with severe systemic hypertension were compared with those of 70 patients with hypertrophoic cardiomyopathy and normal blood pressure. Systolic anterior movement of the mitral valve and/or mid-systolic closure of the aortic valve were found in 82 per cent of patients with obstructive and 35 per cent of patients with non-obstructive hypertrophic cardiomyopathy. These features were not seen in patients with hypertension. The conventional echocardiographic features of left ventricular hypertrophy and function did not permit distinction between hypertensive heart disease and hypertrophic cardiomyopathy. The echocardiographic diagnosis of hypertensive heart disease from hypertrophic cardiomyopathy is, therefore, difficult unless systolic anterior movement of the mitral valve and/or mid-systolic closure of the aortic valve can be shown.

Arrhythmia in hypertrophic cardiomyopathy: exercise and 48 hour ambulatory electrocardiographic assessment with and without beta adrenergic blocking therapy

Submaximal treadmill exercise electrocardiography and 48 hour ambulatory electrocardiographic monitoring were performed in 30 patients with hypertrophic cardiomyopathy both with and without beta adrenergic blocking therapy. During ambulatory electrocardiographic monitoring 1 patient (3 percent) had no arrhythmia, 14 patients (46 percent) had supraventricular tachycardia or paroxysmal atrial fibrillation, 13 (43 percent) had multiform or paired ventricular extrasystoles and 8 (26 percent) had ventricular tachycardia. The frequency of these ventricular arrhythmias was almost identical with and without beta adrenergic blocking drugs (mean dose in "propranolol equivalents" 280 mg daily). With beta blocking therapy fewer patients had supraventricular tachycardia; however, the difference was not significant. During exercise testing 18 patients (60 percent) had ventricular extrasystoles and 3 patients (10 percent) had paired ventricular extrasystoles and the frequency was almost identical with and without beta adrenergic blocking therapy. No routine echocardiographic or hemodynamic measurement predicted the serious ventricular arrhythmias. It is concluded that asymptomatic ventricular arrhythmia is a common occurrence in patients with hypertrophic cardiomyopathy and its frequency is not reduced with beta adrenergic blocking therapy. Because occult arrhythmia may be the cause of sudden death it is important to detect it in these patients so that an effort can be made to improve prognosis with specific antiarrhythmic treatment.

Prevalence of arrhythmias during 24-hour electrocardiographic monitoring and exercise testing in patients with obstructive and nonobstructive hypertrophic cardiomyopathy

Many patients with hypertrophic cardiomyopathy die suddenly and unexpectedly, a significant number perhaps due to arrhythmia. Of 100 patients initially evaluated for signs or symptoms suggestive of heart disease or a family history of hypertrophic cardiomyopathy, 51 were selected solely because they met the echocardiographic criteria for the disease, and 49 patients were selected primarily because they had: 1) normal sinus rhythm despite left atrial enlargement, 2) a history of syncope, 3) a family history of premature death, or 4) a history of paroxysmal atrial fibrillation. All 100 patients were studied by 24-hour ambulatory electrocardiographic monitoring and 74 of them also underwent treadmill exercise testing. More than 50% of patients in repetitive ventricular premature depolarizations, including 19% who had ventricular tachycardia. Monitoring was superior to exercise testing for exposing these arrhythmias. Two patients experienced cardiac arrest within 2 months of monitoring; in each, monitoring had revealed ventricular tachycardia. Two patients with paroxysms of supraventricular tachycardia during monitoring developed fixed atrial fibrillation within 1 year. These preliminary observations suggest that monitoring may help identify patients at increased risk for significant arrhythmic events.

Idiopathic hypertrophic subaortic stenosis in the young

Thirty-six young patients with idiopathic hypertrophic subaortic stenosis were studied. Twenty-seven patients were male and 9 female, and their mean age was 11.3 years (range 5 months to 20 years). Twenty-three patients (64 percent) had symptoms, the most common being dyspnea, angina and syncope. Diagnostic difficulties were encountered frequently in younger patients, especially those with right heart involvement, and in asymptomatic patients with murmurs suggestive of other cardiac defects. Patients were classified retrospectively into three groups on the basis of management. The first group consisted of 16 patients who were operated on; 4 of these patients died, 1 operatively and 3 suddenly late postoperatively (at 1.6, 2 and 10 years). The 12 long-term survivors (average follow-up period 6.2 years) have had good relief of symptoms. The second group comprised seven patients treated with propranolol; none of these died. The 13 patients in the third group received no therapy; 7 of these patients died, 6 suddenly and 1 from congestive cardiac failure. Idiopathic hypertrophic subaortic stenosis is a serious disorder that may present at any age and that may be difficult to diagnose. All patients with this disorder should be treated with propranolol; surgical intervention, although it does not totally abolish the risk of sudden death, appears to offer symptomatic improvement in most cases over a long-term follow-up period.

Hypertrophic cardiomyopathy in the aged

Although usually considered a disease of young or middle-aged adults, hypertrophic cardiomyopathy is not infrequently seen in older patients as well. Twenty of 23 cases of hypertrophic cardiomyopathy seen in the past 2 1/2 years at our institution have been in patients whose average age was 65 years, and who ranged up to 76 years. Sixteen of these had evidence of an obstructive component at cardiac catheterization or echocardiography. Symptoms and signs were similar to those described for the younger patients in the literature, but were often attributed to other causes, including valvular aortic stenosis, arteriosclerotic or hypertensive heart disease, or cerebrovascular disease. Left ventricular hypertrophy was more consistently present on ECG than on x-ray. The not-infrequent occurrence of hypertrophic cardiomyopathy in older patients, predominantly females, indicates that the natural history of this disease includes a group who suffer few or no symptoms until late in life. Clinical management of younger patients with this diagnosis should be considered in light of this more favorable possible course.

"Malignant" hypertrophic cardiomyopathy: identification of a subgroup of families with unusually frequent premature death

Eight families were identified in which premature cardiac death due to hypertrophic cardiomyopathy occurred with unusual frequency. A total of 69 first degree relatives in the eight families were studied; 41 relatives had evidence of hypertrophic cardiomyopathy and 31 (75 per cent) died of their heart disease. Eighteen of these 31 patients were less than 25 years of age at the time of death. Death was sudden and unexpected in 23 of the 31 patients; in 15 of these 23 patients sudden death was the initial manifestation of cardiac disease. The remaining eight patients (seven were from two families) died after a chronic cardiac illness characterized by congestive heart failure, atrial fibrillation or thromboembolic events. Hence, premature cardiac death occurs frequently in certain families with hypertrophic cardiomyopathy. Such deaths are usually sudden, often occur in previously asymptomatic subjects and are common in children and young adults. These findings suggest that some families may manifest an unusually virulent expression of hypertrophic cardiomyopathy. Although this study cannot establish the precise prevalence with which "malignant" hypertrophic cardiomyopathy occurs, such families appear to be uncommon.

Long-term clinical course and symptomatic status of patients after operation for hypertrophic subaortic stenosis

Long-term results of operation for IHSS were reviewed in 124 patients operated upon between 1960 and 1975. Most patients improved symptomatically and manifested marked reduction in LV outflow gradient at rest postoperatively. However, ten (8%) patients died of causes related to operation, 14 (12%) had persistent or recurrent severe functional limitation, and 11 (9%) died up to 13 years postoperatively due to hypertrophic cardiomyopathy. Overall annual mortality rate was 3.5% and was 1.8% for late deaths alone. Of 11 late postoperative deaths, six were sudden and five were due to chronic heart failure. Atrial fibrillation was significantly more common in patients who died late postoperatively than in survivors. Nine of the 11 late deaths had associated medical problems that may have contributed to their outcome. In conclusion, long-lasting clinical improvement occurred in most patients who survived operation for IHSS. However, 12% of patients deteriorated clinically over the 5.2 year average follow-up, and there is continued, small annual mortality.

Electrophysiologic findings in patients with idiopathic hypertrophic subaortic stenosis

Thirteen patients with catheterization-proved idiopathic hypertrophic subaortic stenosis underwent intracardiac electrophysiologic study. There was a large incidence of arrhythmias and a strikingly large incidence of conduction system abnormalities among these patients. The P-A and A-H intervals were normal in all patients. Atrial pacing resulted in Mobitz type 1 block proximal to the His bundle at an abnormal rate (less than 140/min) in 2 of 12 patients (17 percent). H-V intervals were prolonged (greater than 50 msec) in 10 of 12 patients (83 percent) and were greater than 60 msec in 7 patients (58 percent). The atrial effective refractory period was prolonged in 3 of 12 patients and was markedly prolonged in 1 of them. Effective refractory period of the atrioventricular (A-V) node, determined in five patients, was prolonged in three. Dual responses of the A-V node to atrial extrastimuli were found in seven patients. Dual A-V nodal repsonses were evoked with propranolol in three patients and persisted in the other four patients with dual responses despite propranolol administration.

Sudden death in patients with hypertrophic cardiomyopathy: characterization of 26 patients with functional limitation

Sudden death is a recognized complication in symptomatic patients with hypertrophic cardiomyopathy. However, its occurrence in patients with no or transient previous cardiac symptoms presents a particularly challenging diagnostic and therapeutic dilemma. Therefore, 26 patients with hypertrophic cardiomyopathy whose death was the first definitive manifestation of cardiac disease were evaluated. Their ages ranged from 8 to 49 years (mean 18) and 23 were less than 25 years of age; 19 were male and 7 female. Of the 26 patients, 13 died during or immediately after moderate or severe physical exertion. Of 12 patients with previous cardiac catheterization, 6 had no or a small left ventricular outflow tract gradient under basal conditions and 6 had an outflow gradient of 50 mm Hg or greater. Left ventricular end-diastolic pressure was elevated in nine patients, and the ventricular septum was moderately to severely thickened (17 mm or more) in all patients. The electrocardiogram was abnormal in all 19 patients studied before death. Thus, sudden death may be the first definitive manifestation of cardiac disease in some patients with hypertrophic cardiomyopathy. Although the effects of patient selection in this study group cannot be excluded, sudden death was common in children and young adults and was often related to physical exertion; each patient showed a distinctly abnormal electrocardiogram and moderate to severe ventricular septal thickening.

Echocardiographic assessment of left ventricular filling and septal and posterior wall dynamics in idiopathic hypertrophic subaortic stenosis

In order to study left ventricular function in idiopathic hypertrophic subaortic stenosis (IHSS), left ventricular echograms were analyzed by computer and compared with results in normal subjects. Systolic function was consistently normal or above normal even in the presence of severe diastolic abnormalities. Wide variation in diastolic function in IHSS allowed separation of patients into three groups on the basis of the left ventricular peak filling rate. Because of the severe septal hypertrophy and hypokinesia, peak left ventricular filling rate is predominantly determined by the rate of free wall thinning. Patients in group 1 had rapid left ventricular filling rates, those in group 2 had normal filling rates, and those in group 3 had slow filling rates. With reduction in left ventricular peak filling rate caused by impaired free wall thinning, there was progressive increase in 1) duration of the rapid filling phase, 2) delay of mitral valve opening, 3) asynchrony between septum and posterior wall, 4) incidence of angina, and 5) incidence of atrial fibrillation.

Disproportionate ventricular septal thickening in the developing normal human heart

A disproportionately thickened ventricular septum containing numerous disorganized cardiac muscle cells is the most characteristic anatomic feature of hypertrophic cardiomyopathy. Since information concerning ventricular wall thicknesses and cellular arrangement in the developing heart may be pertinent to understanding the genesis of hypertrophic cardiomyopathy, morphologic observations were made in 151 normal human embryos, fetuses and term infants. Disproportionate ventricular septal thickening (septal-free wall ratio greater than or equal to 1.3) was present in 94% of embryos and young fetuses; in over one-third disproportionate thickening was particularly pronounced (septal-free ratio greater than or equal to 2.0). Disproportionate septal thickening was also present in 65% of older fetuses, but in only 12% of infants over two weeks of age. Septal-free wall ratio decreased in a curvilinear fashion with increasing age and apporixmated unity in the newborn. This phenomenon occurred because, while both ventricular septal and left ventricular free wall thicknesses increased directly with age, free wall thickness increased at a greater rate than septal thickness, particularly after birth. Marked cellular disorganization in the septum was not a feature of the hearts studied.

Asymetric septal hypertrophy in childhood

Although considerable information is available concerning the clinical features and natural history of asymmetric septal hypertrophy (ASH) in adults, little is known of this disease in children. The clinical characteristics and course of 46 children with ASH, who were evaluated at the National Heart and Lung Institute, have been analyzed. Twenty-four children had obstruction to ventricular outflow; 22 children had no obstruction to ventricular outflow, including 11 patients without overt manifestations of cardiac disease other than echocardiographic evidence of ASH. Thirty-five of the 46 children have been followed for one to 16 years (average 7.4 years). These latter children represent that subgroup of patients with ASH referred to the National Heart and Lung Institute and diagnosed prior to the general availability of echocardiography. The clinical course of these patients was variable. Fourteen (40%) of the 35 patients improved or remained stable, including four patients who received propranolol. Ten (29%) of the 35 patients deteriorated clinically and 11 (31%) of the 35 patients died suddenly (4% mortality per year). Two of the patients who died suddenly had previously undergone operation (six and 13 years previously) with resultant abolition of the outflow gradient; four others were taking propranolol. Neither symptomatology, electrocardiographic abnormalities, heart size, left ventricular ejection or upstroke time, magnitude of outflow gradient, or left ventricular end-diastolic pressure proved predictive of sudden death. Excluding patients who had previous operation, eight (40%) of 20 patients with obstruction who were followed long term and one (9%) of 11 patients without outflow obstruction died suddenly. Thus, the clinical and hemodynamic spectrum of ASH in childhood is broad. However, deterioration in clinical condition or sudden death has been relatively common in children with overt signs of cardiac disease.

Treadmill arrhythmias in patients with idiopathic hypertrophic subaortic stenosis

Treadmill tests were performed in 19 patients with previously documented idiopathic hypertrophic subaortic stenosis (IHSS). Arrhythmias occurred in 79 percent (15) of the patients, and new arrhythmias not previously documented occurred in over 50 percent (10) of the patients. Paroxysmal supraventricular tachycardia (PSVT), ventricular premature beats (VPBs) (two or more per minute) or atrial premature beats (APBs) (three or more per minute) occurred in 10 of 19 patients. There was no association between treadmill arrhythmias and clinical symptoms, hemodynamic data, or electrocardiographic features. Propranolol administration resulted in failure of exercise to induce PSVT in one patient and had no effect on PSVT in two others, nor any effect on maximum frequency of APBs or VPBs. Treadmill testing is more productive than retrospective analysis of ECGs for characterizing arrhythmias in IHSS.

Idiopathic hypertrophic subaortic stenosis

The clinical and laboratory findings in 29 patients with idiopathic hypertrophic subaortic stenosis are presented. Dyspnoea during exercise, angina pectoris, syncope combined with left ventricular hyperthrophy on ECG and chest X-ray and a systolic ejection murmur at the apex and the left sternal border are the most important findings. The findings were different in patients below and above 30 years of age. Most of the patients below 30 were in function group I, had a normal heart volume on chest X-+ray, and syncope was related to exercise. All patients above 30 had symptoms, nearly all were in function groups II-IV and often complained of palpitations, had increased heart volume on chest X-ray, sign of enlarged left atrium or atrial fibrillation of ECG. Syncope was not related to exercise, but always associated with palpitation in patients above 35 years of age. Pathologic Q waves were found more often in the younger age group. The differential diagnosis is discussed in relation to fixed aortic stenosis, mitral valve disease, ventricular septal defect, coronary artery disease, and hypertrophic cardiomyopathy without outflow tract obstruction.

Pathological features of hypertrophic obstructive cardiomyopathy (HOCM) in the elderly

The pathological findings and available clinical data in 15 necropsy cases of HOCM, aged over 61 years, are reported. Three patients were in the eighth decade and 4 in the ninth; 8 were women. Five presented as sudden death, 2 died in congestive cardiac failure, and 7 died of unrelated conditions and HOCM was an apparently incidental postmortem finding. Compared with cases under 60 years, the hearts of the elderly patients were heavier and less likely to show typical asymmetrical hypertrophy, the free wall of the left ventricle also being thickened in two-thirds of the cases over 60 years. Most of the elderly cases showed a distinctive band of fibrous thickening over the upper part of the interventricular septum. This lesion had a "mirror image" relation to the lower part of the aortic surface of the anterior mitral cusp, with the histological features of a friction lesion. It appears to be a morphological expression of the systolic contact of anterior mitral cusp and interventricular septum seen on cineangiography and thus diagnostic of HOCM. Once formed, the fibrous band appears to persist even if the obstructive element disappears. It is, therefore, a valuable diagnostic feature indicating a diagnosis of HOCM in an age group where the morphology is usually not the classical asymmetrical form and in which this diagnosis is usually not considered.