Idiopathic hypertrophic subaortic stenosis in pregnancy.

The coexistence of pregnancy and idiopathic hypertrophic subaortic stenosis is a potentially dangerous combination. We report a 23-year-old white woman with idiopathic hypertrophic subaortic stenosis and pregnancy who presented with severe symptoms (Class IV) and modest outflow obstruction associated with marked mitral regurgitation. After delivery, the evidence for significant mitral regurgitation regressed, while the outflow obstruction seemed unchanged. However, she returned to Functional Class II. We review the mechanisms by which pregnancy and labor may alter the hemodynamics of idiopathic hypertrophic subaortic stenosis and we discuss recommendations for the management of these patients during pregnancy, labor, and the immediate postpartum period. We conclude that despite increasing symptoms, most women with diopathic hypertrophic subaortic stenosis can tolerate pregnancy and a vaginal delivery.     

Idiopathic hypertrophic subaortic stenosis and ventricular preexcitation

Two patients who had idiopathic hypertrophic suBAortic stenosis (IHSS) and type A ventricular preexcitation were studied and showed variations of the subvalvular flow gradients. The increase in subvalvular gradient, occurring at a time when preexcitation developed, was associated with significant increase of the systolic murmur and the systolic anterior motion of the mitral valve. In patient 1, the significant increase in subvalvular gradient during ventricular preexcitation was also confirmed by catheterization of the left side of the heart. The increase of the gradient with the development of the ventricular preexcitation was apparently due to decreased end-diastolic volume. The importance of ventricular volume considered as a variable affecting outflow tract gradient in idopathic hypertrophic suBAortic stenosis is emphasized.     

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.     

Idiopathic hypertrophic subaortic stenosis in the elderly

In a 24-month period, 27 patients with idiopathic hypertrophic subaortic stenosis (IHSS), ages 65-80 years, were observed. Diagnoses were made by echocardiography (24 patients), cardiac catheterization (one patient), and both methods (two patients). The most common symptoms were angina (17 patients), dyspnea (13 patients), and syncope (11 patients). Two patients were asymptomatic, while another complained only of vague retrosternal chest discomfort with exertion. One asymptomatic patient had a completely normal physical examination, but electrocardiography (ECG) demonstrated a pattern of left ventricular hypertrophy. Another patient had an inconsistent apical holosystolic murmur. Two patients had alpha streptococcal endocarditis; neither was known to have pre-existing valvular disease. Fourteen patients had ECG criteria for left ventricular hypertrophy (LVH). Three patients were known to have associated aortic valve disease. The symptoms of IHSS may be nonspecific; asymptomatic patients with and without cardiac murmurs may be observed. Coexisting valvular disease, coronary artery disease, and bacterial endocarditis were documented. Patterns of myocardial infarction on ECG were not seen in these 27 patients.     

Idiopathic hypertrophic subaortic stenosis: Long-term surgical follow-up

The results of surgery in 43 patients with idiopathic hypertrophic subaortic stenosis are reported. Twenty-eight patients were male and 15 female; their mean age was 34 years. Dyspnea, angina pectoris and dizziness or syncope were the most common symptoms, in decreasing frequency. Before the operation, 3 patients were in New York Heart Association functional class I, 9 in class II and 31 in classes III and IV. The mean resting peak ventricle-arterial systolic pressure gradient was 77 mm Hg (39 patients), and mean left ventricular end-diastolic pressure was 22 mm Hg (34 patients). The operative mortality rate was 16 percent (7 of 43 patients) for the entire group, but only 8 percent for patients who underwent isolated left ventricular outflow tract myectomy (3 of 36 patients). There were four late sudden deaths. One patient has been lost to follow-up. The remaining 31 patients have been followed up for a mean of 84 months (range 12 to 160 months); 14 patients are in functional class I, 14 in class II and 3 in classes III and IV. Of the symptomatic patients, six are taking propranolol and eight are taking digitalis or diuretic agents, or both. Complications included complete heart block in 5 patients, complete left bundle branch block in 15 and left ventricular aneurysm in 3. Our study, which is one of the largest with the longest postoperative follow-up period, documents that surgery results in good to excellent alleviation of symptoms in survivors. We currently recommend surgery for the symptomatic patient who has not responded to therapy with propranolol.     

Idiopathic hypertrophic subaortic stenosis in a patient with mirror-image dextrocardia.

A 42-year-old man with mirror-image dextrocardia was found to have idiopathic hypertrophic subaortic stenosis. The coexistence of these uncommon congenital cardiovascular anomalies was previously reported in only one patient.     

Idiopathic hypertrophic subaortic stenosis in aortic valve disease-diagnosis using echocardiography]

In three patients with valvular aortic disease in addition isiopathic hypertrophic subaortic stenosis (IHSS) was proven by echocardiography. From the clinical standpoint the dynamic subvalvular stenosis was not supposed in all cases. IHSS was echocardiographically characterized by asymmetrical septum hypertrophy and systolic anterior movement of the anterior mitral leaflet. Isolated aortic valve insufficiency was found in two patients, and combined stenosis and insufficiency in one patient. Mitral leaflet fluttering - indicative of aortic valve insufficiency - was observed in two patients. The identification of the dynamic subvalvular stenosis in patients with valvular aortic disease is important for the therapeutical approach. Echocardiography is very suitable for the diagnosis of this combined heart disease.     

Idiopathic hypertrophic subaortic stenosis and aortic regurgitation in an 84-year-old man

During the ninth decade of life, idiopathic hypertrophic subaortic stenosis (IHSS), particularly when associated with other cardiac disorders, presents a confusing clinical problem. Unless the physician has a high index of suspicion, the diagnosis is easily overlooked, and consequently inappropriate management of the patient may lead to serious complications. One such case in an 84-year-old man is described. Administration of certain drugs may only intensify symptoms. Echocardiography is invaluable for diagnosis. Pertinent clinical features of IHSS in the eighth and ninth age decades are outlined.     

Hypertension and hypertrophic subaortic stenosis

In eight patients hypertension coexisted with hypertrophic subaortic stenosis, in every instance documented hypertension preceding any clinical evidence of muscular subaortic stenosis. In seven patients complete cardiac catheterization demonstrated typical hypertrophic subaortic stenosis. In the one patient not catheterized, the clinical picture and postmortem findings demonstrated muscular subaortic stenosis. Obstruction of the outflow tract became clinically evident during treatment for hypertension or during periods of extreme lability of the blood pressure. Amyl nitrite was useful in making the diagnosis, especially when the blood pressure was elevated.