We sought to determine the ejection variables that are principally responsible for increases in isovolumic ventricular relaxation rate observed with increases in stroke volume. In nine isolated canine hearts, left ventricular ejection was controlled by patterns specially designed to isolate the ejection parameters most critical to isovolumic relaxation rate. When stroke volume was augmented by ...

The purpose of this study was to determine the mechanism of the decrease in left ventricular stroke volume during spontaneous inspiration. We determined the transmural pressures of the left heart by measuring left atrial and diastolic left ventricular pressures relative to esophageal pressure. We estimated the directional changes in end-systolic and end-diastolic volumes of the left ventricle b...

BACKGROUND Several studies have demonstrated better outcomes for carotid endarterectomy (CEA) at high-volume hospitals and providers. However, only a few studies have reported on the impact of surgeons' specialty and volume on the perioperative outcome of CEA. METHODS This is a retrospective analysis of CEA during a recent 2-year period. Surgeons' specialties were classified according to thei...

Critical care practices have evolved to rely more on physical assessments for monitoring cardiac output and evaluating fluid volume status because these assessments are less invasive and more convenient to use than is a pulmonary artery catheter. Despite this trend, level of consciousness, central venous pressure, urine output, heart rate, and blood pressure remain assessments that are slow to ...

OBJECTIVES Fluid volume optimization guided by stroke volume measurements reduces complications of colorectal and high-risk surgeries. We studied whether dehydration or a strong hemodynamic response to general anesthesia increases the probability of fluid responsiveness before surgery begins. METHODS Cardiac output, stroke volume, central venous pressure and arterial pressures were measured i...

While the steady-state effects of positive pleural pressure on the circulation have been extensively studied, less is known about the immediate effects of positive intrathoracic pressure on cardiac dynamics. Therefore, we performed electrocardiographically gated radionuclide ventriculography with a respiratory gating technique in nine healthy subjects during quiet breathing and during expiratio...

BACKGROUND AND PURPOSE Low socioeconomic status is associated with stroke fatality; however, the mechanism behind this association is uncertain. We sought to determine whether residence in a low-income neighborhood was associated with admission to low-volume facilities and whether this contributed to differences in fatality after stroke. METHODS All hospitalizations for ischemic stroke from A...

A dye dilution and an electric conductivity method for measuring end-diastolic volume and stroke volume of the left ventricle are described, and equations for the calculation of stroke volume are given. When dye is injected "instantaneously" into the left ventricle during diastole, the aortic dye concentration-time curve obtained is a step-like curve and not a smooth curve. The ventricle emptie...

OBJECTIVE To follow-up and estimate cardiac function in 11 heart failure patients with moderate to severe mitral regurgitation who underwent cardiac resynchronization therapy (CRT) and to compare echocardiography to the rebreathing method (indirect Fick method) which were used for estimation. DESIGN Prospective, observational, clinical study. SETTING University teaching hospital. METHODS ...