Left ventricular performance and blood catecholamine levels in the isolated heart

¹ Department of Pediatrics, Harvard Medical School, and Cardiology Division of the Medical Service, Children's Hospital Medical Center, Boston, Massachusetts

Left ventricular performance in the isolated heart of the dog as expressed by the peak systolic intraventricular pressure was observed during control periods when the heart was perfused with blood from a healthy anesthetized donor and after the donor was removed and the heart perfused with blood oxygenated by isolated lungs. Heart rate, coronary perfusion pressure, ventricular end-diastolic pressure, and stroke volume were maintained constant throughout. While the heart was perfused with blood from a donor, ventricular performance showed no tendency to decline, although coronary flow invariably increased. On removing the donor and perfusing the heart with blood oxygenated by isolated lungs, myocardial performance declined in proportion to the decline in the total catecholamine concentration of the perfusing blood. Restoration of catecholamine levels by infusing epinephrine and norepinephrine also restored left ventricular performance.

Key Words: epinephrine • norepinephrine • supported heart • myocardial oxygen consumption • coronary flow

Submitted on February 3, 1966