This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Gross, G. J. Articles by Hardman, H. F. Search for Related Content PubMed PubMed Citation Articles by Gross, G. J. Articles by Hardman, H. F. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB PROPRANOLOL HYDROCHLORIDE

Circulation, Vol 58, 663-669, Copyright © 1978 by American Heart Association

ARTICLES

Beneficial actions of N-dimethyl propranolol on myocardial oxygen balance and transmural perfusion gradients distal to a severe coronary artery stenosis in the canine heart

GJ Gross, DC Warltier and HF Hardman

The purpose of the present study was to compare the effects of N- dimethyl propranolol (DMP), the quaternary derivative of propranolol, and propranolol on the transmural distribution (endo/epi) of coronary blood flow in normal and ischemic regions of the myocardium. The distribution of blood flow between subendocardium and subepicardium of a nonischemic region and one distal to a severe left circumflex coronary artery stenosis was determined by use of tracer microspheres (15 microgram) in intact dog hearts. DMP (1,5 and 10 mg/kg I.V.) produced a small dose-related increase in endo/epi of the nonischemic region (1.15 +/- 0.04--1.24 +/- 0.05), whereas a larger increase was observed in the ischemic region (0.61 +/- 0.08--1.09 +/- 0.10). DMP also produced a significant increase in ischemic subendocardial blood flow (0.59 +/- 0.12--0.76 +/- 0.11 ml/min/g). Similarly, propranolol (0.5 and 1.0 mg/kg I.V.) produced a small increase in endo/epi of the nonischemic region (1.18 +/- 0.08--1.30 +/- 0.07) and a larger increase in the ischemic region (0.72 +/- 0.17--1.18 +/- 0.09). However, propranolol did not increase ischemic subendocardial blood flow. It is concluded that DMP may be an alternative to propranolol in certain types of acute myocardial ischemia when beta-adrenergic blockade is undesirable.