[Progress in the therapy of acute and chronic cardiac insufficiency by means of systemic vasodilators. Studies with prazosin and nitroglycerin].
In acute and chronic left heart failure peripheral resistance is elevated due to increased sympathetic tone. This should compensate the decrease in stroke volume. In the diseased left ventricle however the augmentation of afterload leads to further reduction of stroke volume and to increase of heart size and myocardial oxygen consumption. This vitious cycle may be interrupted by vasodilators. Drugs like nitroglycerin, mainly acting on the venous system, reduce preload and thereby relieve symptoms of pulmonary congestion (backward failure). Phentholamin on the other hand primarily reduces afterload by an action on the resistance vessels and thereby increases cardiac output (forward failure). Nitroprusside has effects on both, the capacity and resistance vessels. So nigroglycerin is the remedy of choice in acute pulmonary edema. Nitroprusside in leftf heart failure in acute myocardial infarction and Phentolamin in acute left ventricular failure due to critical rise in blood pressure. For long term treatment of chronic left heart failure (coronary heart disease, cardiomyopathy, rheumatic heart disease) hydralazin or prazosin may be used as well as long acting nitrates.
D001794:Blood Pressure / Q000187:drug effects; D002395:Catecholamines / Q000097:blood; D006333:Heart Failure / Q000188:drug therapy*; D006352:Heart Ventricles / Q000187:drug effects; D006801:Humans; D005996:Nitroglycerin / Q000627:therapeutic use*; D011224:Prazosin / Q000627:therapeutic use*; D011799:Quinazolines / Q000627:therapeutic use*
D002395:Catecholamines; D011799:Quinazolines; D005996:Nitroglycerin; D011224:Prazosin
Fortschritte in der Therapie der akuten und chronischen Herzinsuffizienz durch den Einsatz systemischer Vasodilatatoren. Untersuchungen mit Prazosin und Nitroglyzerin.