To assess the effects of a natural volume overload state (pregnancy) on left ventricular function we recorded echocardiograms each trimester (TM) and four to 12 weeks postpartum. Heart rate increased from 77 ± 2 (SEM) to 88 ± 2 heats/min (TM I vs TM 3, P < 0.01) and declined to 69 ± 2.0 beats/min postpartum (P < 0.05 vs TM 3). Despite these changes, end-diastolic dimension increased from 46.3 ± 0.7 to 50.7 0.7 mm (TM I vs TM 3, P < 0.01) and decreased postpartum to 47.5 ± 0.7 mm (P < 0.01 vs TM 3). Calculated stroke volume and cardiac index changed correspondingly, but ejection fraction, percent of fractional shortening and mean normalized rate of internal diameter shortening were not significantly altered. Left ventricular wall mass increased during gestation but decreased between TM 3 and postpartum 162 ± 8.3 vs 143 ± 6.2 g, P < 0.05). THE OPTIMAL MANAGEMENT of pregnancy, especially for women with heart disease, requires an understanding of the basic hemodynamic stresses that occur during gestation. The most important hemodynamic change in the maternal circulation during pregnancy is an increase in cardiac output of 30-40%.' This alteration has several unique features: 1) the augmentation occurs relatively early in pregnancy (20-24 weeks), 2) it cannot be explained entirely on the basis of fetal needs, and 3) fluctuations in cardiac output occur with changes in body position as the gravid uterus impinges in varying degree on the inferior vena cava, thus altering systemic venous return.2 A second fundamental hemodynamic change is a decrease in peripheral vascular resistance as a consequence of the creation of a low-resistance circuit (placenta). This alteration is manifest as a widened pulse pressure due to a decline in levels of diastolic arterial blood pressure and a fall in mean blood pressure.3 A third hemodynamically important shift during pregnancy is a dramatic increase in maternal blood volume approaching 40% above nonpregnant values.4While the effects on cardiac output have been welldocumented, there is conflicting information concerning left ventricular performance during pregnancy. Normal, augmented and depressed function have been reported at various stages of gestation."' In addition, normal gestation provides the opportunity to study a naturally occurring volume overload state in normal human subjects. This study was designed to provide quantitative information regarding serial alterations in left ventricular performance during normal pregnancy. Methods Study DesignThe study group was comprised of 19 pregnant women who had normal, full-term spontaneous deliveries. They were 19-37 years of age (mean = 25) and had no cardiovascular disease as assessed by a complete history and physical examination. The resting electrocardiogram was within normal limits in all subjects. All subjects underwent identical procedures at the end of the first and second trimesters and during the third trimester within one to two weeks before the expected date of delivery and six to 12 weeks postpartum. At each visit the f...

DOBUTAMINE IN HEART FAILURE/Pozen et al. SUMMARY Eighteen patients with congestive heart failure (CHF) complicating coronary artery disease (CAD) and seven patients with CHF due to primary cardiomyopathy (CM) were studied during infusions of dobutamine in doses of 2.5-15.0 ,g/kg/min. There were statistically significant (p < 0.05) improvements in cardiac index, stroke volume index, left ventricular stroke work index and nuclear ejection fraction in both groups. Significant decreases (p < 0.05) in pulmonary capillary wedge pressure, right atrial pressure, and systemic and pulmonary vascular resistances were also observed in both groups. However, five patients increased an already elevated pulmonary capillary wedge pressure during dobutamine infusion, which was associated with either the development of angina pectoris or with a significant elevation of the mean arterial pressure. In the CAD patients, gated cardiac scans analyzed for segmental wall motion showed improvement in 27% of the abnormally contracting segments during dobutamine infusion. Finally, the effects of dobutamine on myocardial metabolism were assessed with arterial and coronary sinus lactate analysis. Fourteen of the 18 CAD patients (78%) showed no metabolic abnormality during dobutamine infusion; four CAD patients (22%), three of whom developed typical angina pectoris, displayed abnormal lactate metabolism. None of the CM patients developed angina pectoris or displayed abnormal lactate metabolism. Of the seven patients with an adverse hemodynamic or metabolic response, four had recently been withdrawn from propranolol therapy. In conclusion, dobutamine produced favorable effects on hemodynamics, left ventricular ejection fraction, and segmental wall motion abnormalities in most patients with CHF without a deleterious effect on myocardial metabolism.DOBUTAMINE is a new inotropic agent, structurally related to other catecholamines, that is used to treat patients with congestive heart failure (CHF) of diverse etiologies. Although studies have shown

The relations between reciprocal ST segment depression in the electrocardiogram and infarct size and 10 year prognosis were studied in 315 patients who survived for at least 28 days after a first anterior or inferior myocardial infarction. ST depression was more common in inferior infarcts (72%) than in anterior (37%) ones. It occurred more frequently in complicated infarcts and in the presence of considerable ST elevation. Patients experiencing second or third degree heart block were significantly more likely to show reciprocal changes. The rise in peak cardiac enzyme concentration was higher in patients showing ST depression. In patients with ST depression, peak creatine kinase concentration was 46% higher, aspartate aminotransferase was 39% higher, and lactate dehydrogenase 29% higher after correction for site and complications. A discriminant function analysis selected infarct site, peak aspartate aminotransferase, and magnitude of ST elevation as predictors of the occurrence of ST depression. Age, severity, and smoking status did not significantly improve discrimination. Despite larger increases in peak enzyme concentrations patients with ST depression had marginally fewer subsequent episodes of unstable angina or fatal or non-fatal infarction and a marginally lower 10 year death rate. Neither difference was statistically significant. ST depression occurring early in the acute phase of myocardial infarction is likely to be a reflection of electrophysiological changes taking place at the site of the infarct that is manifested in the contralateral surface of the heart. Other causes, however, such as transient ischaemia at the site of the reciprocal changes or extension of the infarct to contiguous areas cannot be excluded in all cases.