These studies were designed to examine the electrophysiological effects of diphenylhydantoin (Dilantin) on the heart of awake dogs. Recording electrodes were implanted over the sinoatrial node, bundle of His, and right bundle branch, and studies were performed 2 to 6 weeks following recovery. Diphenylhydantoin (10 mg/kg) increased heart rate, shortened A-V conduction time and had little or no e...

THIS YEAR IS THE 113TH ANNIVERSARY of two publications whose relationship was not obvious initially: the observation that neural crest cells migrate away from the neural ectoderm and assume a wide variety of phenotypes (11) and the initial description of what became known as the pacemaking/conduction system of the heart (6). Both of these observations have been expanded logarithmically by advan...

Background: The association between conduction disturbances and atherosclerotic coronary artery disease has been investigated in a few small studies in the early 1970s and the study result was inconclusive. Thereafter some investigators found in their separate study that a group of patients with conduction disturbances that required permanent pacemaker who had coronary atherosclerotic disease t...

THE electrocardiogram in patients with tetralogy of Fallot usually shows right axis deviation and right ventricular hypertrophy. After creation of a systemic-pulmonary artery anastomosis, the work of the left ventricle increases, usually accompanied by a corresponding increase in the pattern of left ventricular loading." 2 Following openheart surgery, with closure of the ventricular septal defe...

Correspondence to Dr Charles Fisch, Krannert Institute of Cardiology, 1111 West Tenth Street, Indianapolis, IN 46202, USA. The earliest electrocardiogram illustrating bizarre intraventricular conduction of supraventricular impulses was published by Sir Thomas Lewis in 1910.' In a subsequent communication Lewis labelled this form of abnormal conduction "aberration" and the ventricular complexes ...

SUMMARY The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces coronavirus-19 disease (COVID-19), has affected many people in Brazil and worldwide. This predominantly affects the organs of system, but it also damages brain, liver, kidneys especially heart. In heart, scientific evidence shows that this virus can damage coronary arteries, generating microvascular dysfunction, fa...

40. Narula OS, Samet P, Javier RP: Significance of the sinus-node recovery time. Circulation 45: 140, 1972 41. Strauss HC, Bigger JT, Saroff AL, Giardina EGV: Electrophysiologic evaluation of sinus node function in patients with sinus node dysfunction. Circulation 53: 763, 1976 42. Hellestrand KJ, Bexton RS, Nathan AW, Spurrell RAJ, Camm AJ: The acute electrophysiological effects of flecainide ...

CARDIAC ELECTROPHYSIOLOGY CLINICS www.cardiacEP.theclinics.com Consulting Editors RANJAN K. THAKUR ANDREA NATALE November 2021 • Volume 13 Number 4