Echocardiographic abnormalities following cardiac radiation.

Five years or more after receiving cardiac radiation, 41 patients with Hodgkin's disease and seminoma in remission were subjected to echocardiography. The abnormalities detected included pericardial thickening in 70%, thickening of the aortic and/or mitral valves in 28%, right ventricular dilatation or hypokinesis in 39%, and left ventricular dysfunction in 39%. In the 23 patients treated by an upper mantle technique with shielding, the incidence of right ventricular abnormalities and valvular thickening was significantly lower than in patients treated with modified techniques. Although no symptoms were attributable to the observed abnormalities, longer follow-up time may reveal important functional implications.

Concurrent aortic and mitral valve echocardiography permits measurement of systolic time intervals as an index of peripheral tissue thyroid functional status.

Systolic time intervals (STI) were measured directly from concurrent aortic and mitral valve echocardiographic tracings in 127 subjects to assess their utility as an index of peripheral tissue thyroid functional status. The subjects were categorized according to clinical symptoms and the results of thyroid function tests into the following 7 study groups: normal subjects (n = 34), overt hyperthyroid subgroup I (n = 12), overt hyperthyroid subgroup II (n = 28), subclinical hyperthyroid (n = 15), subclinical hypothyroid (n = 22), overt hypothyroid subgroup II (n = 6), and overt hypothyroidism subgroup I (n = 10). Compared with normal subjects, overt hyperthyroid subgroup I patients had a significantly shortened mean isovolumetric contraction time (ICT), preejection period (PEP), and PEP/LVET (LVET = left ventricular ejection time; P less than or equal to 0.0005); the overt hypothyroid subgroup I patients also had significantly lengthened mean ICT (P less than or equal to 0.005), PEP, and PEP/LVET (P less than or equal to 0.0005). Compared with normal subjects, overt hyperthyroidism subgroup II patients also had a very significant shortening of ICT (P less than 0.0005) as well as a significantly shortened PEP and PEP/LVET (P less than or equal to 0.005), whereas subclinical hyperthyroid patients (with normal serum free T4 index and total T3, and suppressed TSH by immunoradiometric assay) also had ICT, PEP, and PEP/LVET STI values which were significantly shortened (P less than 0.05) values. Compared to normal subjects, the overt hypothyroid subgroup II patients (who were clinically asymptomatic with reduced serum free T4 index and elevated TSH) had a prolongation of ICT, PEP, and PEP/LVET (P less than or equal to 0.05), whereas the values in subclinical hypothyroid patients were similar to those in normal subjects. From these observations we conclude that in the absence of underlying heart disease, the echocardiographic method used is a rapid, reliable, and sensitive technique for determining STI and provides direct information on peripheral tissue thyroid functional status.

Detection of radiation cardiomyopathy by gated radionuclide angiography.

Twenty-one asymptomatic adults underwent rest and exercise gated radionuclide angiography seven to 20 years after having received mediastinal radiation (2,000 to 7,600 rads) for Hodgkin's disease. None of these patients received cytotoxic chemotherapy. Twelve patients (57 percent) had abnormal left (less than 53 percent at rest and/or greater than 5 percent decrease at peak exercise) and/or right (less than 27 percent at rest and/or greater than 5 percent decrease at peak exercise) ventricular ejection fractions. Previous reports have described myocardial fibrosis occurring late after therapeutic mediastinal radiation; however, the incidence of this occurrence based on clinical follow-up has been low. Rest and exercise radionuclide angiography is a sensitive method for assessing systolic ventricular function and reveals a high prevalence of cardiomyopathy that can be linked to previous radiotherapy.

ACE inhibitors and regression of left ventricular hypertrophy.

Left ventricular hypertrophy (LVH) is a common condition and a powerful independent risk factor for coronary heart disease, congestive heart failure, and other cardiac morbidity. It is associated with the male sex and advancing age. Its most common cause is hypertension, and many antihypertensive agents induce regression of LVH. Angiotensin-converting enzyme (ACE) inhibitors have been shown to reverse LVH by a mechanism as yet unknown. Reduction in afterload and other hemodynamic abnormalities by reduction of blood pressure is clearly a factor, but ACE inhibitors also block adrenergic action and other sympathetic nervous system influences, and the reduction in angiotensin II produces many effects. By inhibiting this potent vasoconstrictor and suppressing its degradation of the powerful vasodilator bradykinin, and by promoting sodium and water excretion, ACE inhibitors contribute to the restoration of normal ventricular function. Angiotensin II promotes protein synthesis in myocardial myocytes, and blocking this action may arrest the hypertrophic process. To determine the effect of angiotensin II on LVH and normalization of LV function, a study is now underway evaluating the effects of lisinopril, a new lysine analog of enalapril, and a diuretic agent in the treatment of hypertension LVH.

Cardiovascular effects of levobunolol eyedrops in healthy subjects.

The cardiovascular side effects of the abrupt cessation of treatment with 0.5% levobunolol hydrochloride eyedrops in 10 healthy subjects (5 women and 5 men) aged 18 to 30 years were investigated in a double-blind randomized crossover study. The subjects received either levobunolol eyedrops or placebo drops for 7 days, then, after a 14-day washout period, they received the alternative drops for 7 days. The heart rate and blood pressure at rest, the maximal heart rate and blood pressure on treadmill exercise stress testing and duration of exercise were recorded before treatment began, at the end of treatment and 14 days after withdrawal of the drops. The mean resting heart rate was significantly lower during treatment with levobunolol than with placebo (p less than 0.05). The mean exercise duration was significantly longer during treatment with levobunolol (p less than 0.05); to our knowledge, we are the first to report this finding. There were no significant differences in mean arterial pressure, double product (product of heart rate and systolic blood pressure) or maximal heart rate between the groups at any measurement.

Physiologic significance of hemodynamic measurements and their derived indices.

The fundamental value of hemodynamic monitoring is that it provides direct physiological measurements. The appropriate use of these requires an understanding of normal cardiac physiology and its alterations in certain disease states. An appreciation of the determinants of cardiac output, coronary blood flow and myocardial oxygen consumption will improve the interpretation and subsequent manipulation of these values when one is confronted with them clinically.

Two-dimensional echocardiographic assessment of mitral stenosis.

A real-time, phased-array, two-dimensional echocardiography system was used to assess mitral valve motion in 30 catheterized patients with pure mitral stenosis. Suitable images for analysis of mitral valve motion were obtained in 25 patients. The valve leaflets were most thickened and immobile at the leaflet tips while maximum mobility was at the leaflet body. Diastolic movement of anterior mitral leaflet toward the septum pulled the posterior mitral leaflet mid-portion inferiorly. Systolic bulging of the mid-portion of the anterior mitral leaflet into the left atrium was seen in 40% (10 of 25). Movement of the anterior mitral leaflet in diastole is primarily due to movement of the whole mitral apparatus in patients with mitral stenosis. The anterior mitral leaflet E to F slopes did not correlate (r=0.38) with the mitral valve area determined at catheterization. Planimetry of the mitral valve area directly from the videotape images compared favorably to the valve area determined at catheterization (r=0.95). Thus, mitral valve area determined by this technique is an accurate noninvasive method for assessing the severity of mitral stenosis.¿

A comparison of real-time, two dimensional echocardiography and cineangiography in detecting left ventricular asynergy.

Left ventricular wall motion was assessed in 105 consecutive patients both invasively, using biplane cineangiography, and noninvasively, by a real-time, phased-array, two-dimensional echocardiography system. Ventricular wall motion in five anatomic areas of the ventricle (anterolateral, posterolateral, apical, septal, and inferior) was analyzed by both methods in a double-blind manner. Two-dimensional echocardiographic images were deemed adequate for analysis in 82% of the regions (430 of 525). Fifty-five discrepancies were noted in the comparison of the remaining 430 regions. The reasons for discrepancies in interpretation between the two methods were established for 54 during retrospective review: 33 were due to echocardiography (inadequate target visualization, observer error, or tangential echo views). Fifteen were related to angiography (overlay of silhouettes or observer error), and six were due to other reasons including definition problems or spatial orientation difficulties. Both real-time, two-dimensional echocardiography and cineangiography have advantages and disadvantages. The techniques used together could provide more complete information concerning ventricular wall movement than is now currently available.

Mitral stenosis with posterior diastolic movement of posterior leaflet.

The echocardiographic diagnosis of mitral stenosis depends in part on the demonstration of abnormal posterior leaflet movement to distinguish it from other conditions that similarly affect anterior leaflet motion. In mitral stenosis the posterior leaflet has been shown to move anteriorly in diastole rather than in the normal posterior direction. A patient presented with clinical evidence of moderate mitral stenosis. The anterior leaflet echo was typical but the posterior leaflet showed posterior diastolic movement. At catheterization moderate mitral stenosis was confirmed. To our knowledge this is the first report of the echocardiographic demonstration of posterior diastolic movement of the posterior mitral leaflet in documented mitral stenosis.

Mitral valve prolapse. Two-dimensional echocardiographic and angiographic correlation.

In order to define baseline descriptive criteria for the diagnosis of mitral valve prolapse with cross-sectional echocardiography, 49 patients undergoing catheterization were examined by a real-time, two-dimensional phased array echocardiographic imaging system. Angiography was used to separate patients into two distinct groups: 15 with normal mitral valve function and 34 with definite mitral valve prolapse. Systolic mitral leaflet and annulus motion were then observed in each patient and similarities and differences were noted between the two groups of patients. Correlative M-mode echocardiographic data were available in 37 patients. Certain two-dimensional echocardiographic findings restricted to the angiographically proven mitral valve prolapse group were defined: 1) posteriorly displaced coaptation of the leaflets, 2) systolic superior movement of one or both mitral leaflets above the level of the mitral ring, and 3) a systolic curling motion of the posterior mitral ring on its adjacent myocardium. One or more of these abnormalities were found in all 34 patients with angiographic mitral valve prolapse. When mitral valve prolapse does occur, the results of two-dimensional echocardiography would suggest that both leaflets are usually involved.

Two-dimensional echocardiographic assessment of vegetative endocarditis.

Real-time, two-dimensional echocardiography was used to document the presence and assess the size and location of vegetative lesions of the cardiac valves and chambers in seven patients with bacterial endocarditis. Anatomic correlation (surgical or autopsy) was accurate in all patients. Two-dimensional echocardiography was shown to be of particular value in determining morphologic characteristics of the lesions since this technique provides spatial information concerning moving cardiac structures. The results of two-dimensional echocardiography were most helpful in determining selected aspects of the clinical care provided for each patient. These data demonstrate that real-time, two-dimensional echocardiography, in combination with M-mode imaging techniques, may be of great potential value in the detection of vegetative endocarditis. Furthermore, reliable assessment of lesion size and location may, in time, become a valuable method for following the morphologic changes that occur in vegetative lesions, and thus determine the efficacy of antibiotic therapy. This information may also provide a means for evaluating certain patients for surgical intervention.

Increasing operability and survival with intra-aortic ballon pump assist.

Intra-aortic ballon pump assist (IABPA) was used over a 12-month period in the management of 41 patients: 5 patients with complications of myocardial infarction in shock whose circulation was supported by IABPA before operation immediately after angiographic and hemodynamic study (group 1); 14 patients with postcardiotomy low-output state who could not be weaned from cardiopulmonary bypass and required IABPA circulatory support either in the operating room or in the intensive care area (group 2); 19 patients with severe myocardial ischemia and unstable circulation in whom IABPA was instituted either before angiography or before saphenous vein bypass operation (group 3); and 3 patients with severe left ventricular dysfunction and left ventricular hypertrophy due to aortic valve or coronary artery disease, or both, in whom IABPA was used before, during and after cardiopulmonary bypass and a corrective operative procedure (group 4). Survival rates for patients in these groups were 2/5,8/14,18/19 and 2/3 respectively (overall survival, 73%). IABPA may increase the postoperative survival of certain high-risk patients with poor left ventricular function due to valvular disease or coronary artery disease, or both. The survival of patients with severe myocardial ischemia and complicated myocardial infarction is improved by IABPA, early angiography and appropriate surgical correction. Left ventricular ejection fraction and the estimate of subendocardial coronary flow by the ratio of the diastolic pressure time index to the tension time index appear to be significant in identifying patients who may benefit from the use of IABPA.