Doppler ultrasound in noninvasive cardiac evaluation. The growing range of applications.

Ultrasound is of proven clinical utility for imaging cardiac structures. Doppler ultrasonic techniques can be used with or without echocardiography for noninvasive hemodynamic studies. The usefulness of Doppler ultrasonic techniques in the noninvasive laboratory has been shown recently at the Massachusetts General Hospital, Boston. In 61 of 100 consecutive patients in a prospective study, Doppler ultrasound provided clinical information that could not be obtained with echocardiographic studies alone. The advantages of this technique for noninvasive cardiac studies are now being recognized in the general medical community. The results of ongoing clinical investigations will help define the role of Doppler echocardiography as a clinically useful diagnostic tool for cardiac evaluation.

Echocardiographic abnormalities in chronic alcoholics with and without overt congestive heart failure.

To assess the type and prevalence of cardiac abnormalities in heavy drinkers with and without overt congestive heart failure, M mode echocardiography was performed in 11 symptomatic chronic alcoholics with dilated (congestive) cardiomyopathy and in 22 asymptomatic chronic alcoholics. Echocardiographic data in both groups were adjusted for age and body surface area using previously derived regression equations. All 11 symptomatic patients had a significantly decreased left ventricular percent fractional shortening (mean 14 percent, normal range 28 to 44) along with significant increases in left ventricular systolic and diastolic dimensions (mean increases of 105 and 48 percent above normal, respectively), left atrial dimension (mean increase 21 percent) and estimated left ventricular mass (mean increase 105 percent). Among the 22 asymptomatic patients, 15 (68 percent) demonstrated significant increases in at least one of the following echocardiographic variables: left ventricular mass, left ventricular dimensions, septal and left ventricular wall thicknesses, and left atrial dimension. Asymptomatic patients could be classified into two subgroups: (1) those with a left ventricular diastolic dimension less than 10 percent above the normal predicted value and an increased left ventricular wall thickness to radius ratio (mean increase 16 percent above normal) and upper normal percent fractional shortening, and (2) those with a left ventricular diastolic dimension 10 to 24 percent above normal and a slightly subnormal thickness to radius ratio and lower normal percent fractional shortening. Echocardiographic abnormalities in asymptomatic chronic alcoholics did not correlate with the presence or absence of auscultatory abnormalities on physical examination and appear to reflect an earlier stage in the spectrum of alcoholic disease before the development of dilated cardiomyopathy.

Echocardiographic assessment of cardiac anatomy and function in hypertensive subjects.

Cardiovascular complications are a major source of morbidity and mortality in hypertensive patients. To assess the prevalence of anatomic and functional abnormalities of the heart in such patients, we studied 234 asymptomatic subjects with mild-to-moderate systemic hypertension by echocardiography. After adjusting the echocardiographic values for age and body surface area, we found abnormally increased ventricular septal and/or posterobasal free-wall thickness in 61% of the hypertensive subjects. We found increased left atrial, aortic root, and left ventricular internal dimension (at end-diastole) in 5-7%, and decreased mitral valve closing velocity (E-F slope) and left ventricular ejection fraction were noted in six and 15% of the subjects, respectively. Four percent of the patients had disproportionate septal thickening (i.e., ventricular septal-to-left ventricular free-wall thickness ratio greater than or equal to 1.3). In contrast to the high prevalence of cardiac abnormalities detected by echocardiography, less than 10% of the hypertensive subjects had abnormal 12-lead ECGs or abnormal chest x-rays. These findings demonstrate a high prevalence of cardiac abnormalities in a population of asymptomatic hypertensive subjects. These abnormalities can be detected by echocardiography before they are otherwise apparent.

Prevalence and characteristics of disproportionate ventricular septal thickening in patients with acquired or congenital heart diseases: echocardiographic and morphologic findings.

Echocardiographic and necropsy studies were performed in 304 patients with various cardiac diseases. The overall prevalence of disproportionate ventricular septal thickening (septal to free wall ratio greater than or equal to 1.3) was 10%. However, it was related to the type of cardiac lesion. Prevalence was high (greater than 20%) in pulmonary stenosis or primary pulmonary hypertension, lower (less than 15%) in Eisenmenger syndrome or aortic or mitral valvular disease and was not present in atrial or ventricular septal defect. In right ventricular overload, prevalence of disproportionate septal thickening correlated with increasing ventricular systolic pressure. None of 16 patients with disproportionate septal thickening studied at necropsy showed marked disorientation of cardiac muscle cells in the ventricular septum, characteristic of genetically transmitted asymmetric septal hypertrophy (ASH). Furthermore, disproportionate septal thickening was demonstrated by echocardiography in only one of 59 first degree relatives of patients with disproportionate septal thickening and associated cardiac diseases. Thus, disproportionate ventricular septal thickening associated with other cardiac diseases usually is due to secondary hypertrophy and is not a manifestation of genetically transmitted ASH.