Publications

In patients with chronic obstructive pulmonary disease (COPD), the clinical differentiation between dyspnea due to left ventricular dysfunction and that due to pulmonary events is difficult. Invasive techniques have been the only reliable diagnostic approach. To assess the potential value of noninvasive techniques in this context, 27 patients with COPD and with clinically suspected left ventricular dysfunction were studied by echocardiography, radionuclide angiography, and right cardiac catheterization. In 20 (74%), adequate echocardiogram were obtained. Of these 20 patients, 17 had normal pulmonary arterial wedge pressures at rest and during submaximal handgrip exercise. Sixteen of these 17 had normal left ventricular performance by all three echocardiographic criteria used; in one patient, two criteria were not interpretable, but the third was normal. Results of radionuclide studies were normal in 15 patients, borderline in one, and not measurable in one. Of the three patients with abnormal wedge pressures, at least one echocardiographic criterion was abnormal in all. Radionuclide data were abnormal in two and not measurable in one. We conclude that left ventricular dysfunction is infrequently present in patients with COPD in whom such dysfunction is clinically suspected, that the two noninvasive techniques described here can be applied successfully to a high percentage of patients with COPD, and that the agreement among echocardiographic, radionuclide, and wedge pressure data is excellent.

To assess the adaptation of the left ventricle to a chronic pressure overload we used echocardiography to study 18 patients with left ventricular hypertrophy caused by systemic arterial hypertension. Increased values for either posterior wall or interventricular septal thickness or both confirmed the presence of left ventricular hypertrophy in all patients and an increase in the average wall thickness to radius ratio was consistent with the development of concentric hypertrophy. No patient had clinical evidence of ischaemic heart disease. Ejection phase indices of left ventricular performance (mean Vcf, fractional per cent of shortening, normalised posterior wall velocity, and ejection fraction) were within the normal range in the basal state in 16 of the 18 patients. The hypothesis is advanced that patients with concentric left ventricular hypertrophy resulting from systemic arterial hypertension usually have normal left ventricular performance in the basal state because values for wall stress remain within the normal range. We conclude that the hypertrophic response to a chronic increase in systemic arterial pressure does not per se result in depression of the basal inotropic state of the left ventricle.

In 38 patients undergoing elective coronary arterial bypass graft surgery, the radiographic dimension of the left side of the heart was determined and echocardiographic studies were performed before and after surgery. On the plain chest x-ray film one week after surgery, all patients showed an increase in the size of the left side of the heart, which usually was not accompanied by an increase in the echocardiographic left ventricular end-diastolic dimension; however, in 25 patients, pericardial fluid was detected soon after surgery, which would explain the enlarged cardiac silhouettes. Several months after surgery, the radiographic size of the heart returned to the preoperative value in most patients, and pericardial fluid was no longer demonstrated on the echocardiogram. Thus, pericardial fluid frequently is found in the first week following coronary arterial bypass graft surgery and may give the impression of increased cardiac size on plain chest x-ray films; however, echocardiographic studies provide a more accurate estimate of left ventricular size and reveal the presence of pericardial effusion.