Electrophysiological and histological observations were made on the heart of the African lungfish. Impulse origin and propagation were studied using simultaneously recorded epicardial and pericardial electrograms. The primary pacemaker site in the lungfish was found to be at the sinus venosus at its junction with the left cardinal vein. Under a variety of circumstances, pacemaker function shift...

Between January 1976 and July 1983, 217 patients with atrial septal defect underwent surgical repair at Children's Hospital. Thirty with a primum atrial septal defect and 26 who underwent cardiac catheterization elsewhere before being seen were excluded from analysis. Of the 161 remaining patients, 52 (31%) underwent preoperative cardiac catheterization, 38 because the physical examination was ...

Objective: The purpose of present study was to obtain a complete understanding about anatomical features and echocardiography of Beluga (Huso huso) species in order to provide standard approaches for performing echocardiography on this sturgeon species.Design - Experimental studyAnimals -10 immature (2.5 years old) Beluga (Huso huso)Procedures- To perform echocardiography, Son...

Persistent left superior vena cava is the most common form of anomalous venous drainage involving the superior vena cava, and represents persistence of the left horn of the embryonic sinus venosus, which normally involutes during normal development to become the coronary sinus. Almost always, a persistent left superior vena cava enters the right atrium through the orifice of an enlarged coronar...

BACKGROUND AND OBJECTIVES Isolated persistent left superior vena cava has an incidence of 0.5% in the normal population, but in patients with congenital cardiopathy its incidence ranges from 3% to 10%. The objective of this report was to present a case of intraoperative diagnosis with transesophageal echocardiography and to emphasize the importance of its routine use in surgical procedures for ...

1. Action potentials from sinus venosus and auricle fibers of spontaneously beating frog hearts have been recorded with intracellular electrodes. 2. Sinus fibers show a slow depolarization, the pacemaker potential, during diastole. The amplitude of this potential varies in different parts of the sinus. In some fibers the membrane potential falls by 11 to 15 mv. during diastole and the transitio...