HOME SUBSCRIPTIONS CURRENT ISSUE PAST ISSUES CARDIOSOURCE SEARCH HELP FEEDBACK		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text 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 Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Watanabe, H. Articles by Sugishita, Y. Search for Related Content PubMed PubMed Citation Articles by Watanabe, H. Articles by Sugishita, Y.

CLINICAL STUDIES

Randomized, double-blind, placebo-controlled study of carvedilol on the prevention of nitrate tolerance in patients with chronic heart failure

Hideki Watanabe, MD^*, Masaaki Kakihana, MD, Sadanori Ohtsuka, MD and Yasuro Sugishita, MD, FACC

^* Department of Cardiology, KINU Medical Association Hospital, Mitsukaido, Japan
Ibaraki Prefectural University of Health Sciences, Ami, Japan
Cardiovascular Division, Department of Internal Medicine, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan

Manuscript received December 16, 1997; revised manuscript received June 15, 1998, accepted July 17, 1998.

Address for correspondence: Dr. Hideki Watanabe, Department of Cardiology, KINU Medical Association Hospital, 13-3 Araigi-cho, Mitsukaido City, Ibaraki 303-0016, Japan
wata-h{at}xa2.so-net.ne.jp

Objectives. This study was designed to evaluate the effect of carvedilol on nitrate tolerance in patients with chronic heart failure.

Background. The attenuation of cyclic guanosine 5'-monophosphate (cGMP) production due to inactivation of guanylate cyclase by increased superoxide has been reported as a mechanism of nitrate tolerance. Carvedilol has been known to combine alpha/beta-blockade with antioxidant properties.

Methods. To evaluate the effect of carvedilol on nitrate tolerance, 40 patients with chronic heart failure were randomized to four groups that received either carvedilol (2.5 mg once a day [carvedilol group, n = 10]), metoprolol (30 mg once a day [metoprolol group, n = 10]), doxazosin (0.5 mg once a day [doxazosin group, n = 10]) or placebo (placebo group, n = 10). Vasodilatory response to nitroglycerin (NTG) was assessed with forearm plethysmography by measuring the change in forearm blood flow (FBF) before and 5 min after sublingual administration of 0.3 mg NTG, and at the same time blood samples were taken from veins on the opposite side to measure platelet cGMP. Plethysmography and blood sampling were obtained serially at baseline (day 0); 3 days after carvedilol, metoprolol, doxazosin or placebo administration (day 3); and 3 days after application of a 10-mg/24-h NTG tape concomitantly with carvedilol, metoprolol, doxazosin or placebo (day 6).

Results. There was no significant difference in the response of FBF (%FBF) and cGMP (%cGMP) to sublingual NTG on day 0 and day 3 among the four groups. On day 6, %FBF and %cGMP were significantly lower in the metoprolol, doxazosin and placebo groups than on day 0 and day 3, but these parameters in the carvedilol group were maintained.

Conclusions. These results indicated that carvedilol may prevent nitrate tolerance in patients with chronic heart failure during continuous therapy with NTG.

Abbreviations and Acronyms   cGMP = cyclic guanosine 5'-monophosphate   FBF = forearm blood flow   NTG = nitroglycerin

This article has been cited by other articles:

				M. Taccetta-Chapnick Using Carvedilol to Treat Heart Failure Crit. Care Nurse, April 1, 2002; 22(2): 36 - 58. [Full Text] [PDF]