Sinus Dysfunction
Sinus Dysfunction Sinus Arrhythmia Sinus arrhythmia occurs in young and healthy individuals and is not a form of sinus node dysfunction. Sinus arrhythmia is characterized by variation in cardiac cycle…
Concept Review
Concept Review Action Potential—Myocardial Cell The different phases of the action potential relate directly to the waveforms, intervals, and segments that constitute a cardiac cycle on the ECG. Each phase…
Transposition of the Great Vessels
Transposition of the Great Vessels Transposition of the great arteries is a congenital malformation in which the heart has atrioventricular concordance and ventriculoarterial discordance. Therefore, the clinical findings are an…
Surgery for Coronary Disease
Surgery for Coronary Disease Surgery for revascularization of the myocardium continues to be an effective and lasting means of managing patients with multivessel coronary artery disease. However, the evolution of…
The Fontan Principle
The Fontan Principle The Fontan principle is applied to patients with single-ventricle congenital heart disease. The ultimate goal is to achieve a circulation in which the systemic venous return is…
Left Ventricular Outflow Tract Obstruction
Left Ventricular Outflow Tract Obstruction CONGENITAL AORTIC STENOSIS Pathologic findings in congenital aortic stenosis can vary. The valve may be bicuspid, tricuspid, or unicuspid, and the commissures may be fused…
The Norwood Principle
The Norwood Principle Hypoplastic left heart syndrome is the most common form of congenital heart disease in which there is only one fully developed ventricle and is the fourth most…
Interrupted and Hypoplastic Aortic Arch
Interrupted and Hypoplastic Aortic Arch INTERRUPTED AORTIC ARCH Interruption of the aortic arch is a rare condition that requires a patent ductus arteriosus for survival. A ventricular septal defect is…
Right Ventricular Outflow Tract Obstruction
Right Ventricular Outflow Tract Obstruction The right ventricular outflow tract includes the right ventricular outlet chamber (or the infundibulum); the pulmonary valve; the main, right, and left pulmonary arteries; and…
Coronary Artery Anomalies
Coronary Artery Anomalies Anomalies of the coronary arteries are rare and include left coronary artery origin from the pulmonary artery, coronary artery fistula, and aberrant origin of the left or…
