Effects of carvedilol and atenolol on arterial pulse curves (plethysmography) and finger temperature after hand cooling.
OBJECTIVE
In a double-blind, parallel study, the effects of 25 mg carvedilol and 50 mg atenolol on peripheral finger circulation and arterial pulse curve configuration were compared.


METHODS
Healthy volunteers (n = 17) were examined at baseline and for 15 min after 60 s of hand cooling in ice-water. Finger temperature and digital plethysmography were recorded each minute from the cooled and the control hands. Measurements were also made before and 2 h after drug administration.


RESULTS
Blood pressure declined from 120/86 to 108/74 mm Hg after atenolol (n = 9), and from 122/88 to 108/73 mm Hg after carvedilol (n = 8). In both groups, baseline finger temperature increased slightly after drug, and a more rapid rise in finger temperature was observed after cooling. There was no group difference in the drug effect on finger temperature, except in the first few minutes after cooling, when temperature recovery was greater after carvedilol. Carvedilol reduced the vasoconstrictor response to local cooling (digital plethysmography), compared both to the value before drug and after atenolol. At rest, carvedilol changed the pulse curves (control hand) towards vasodilatation and high compliance, expressed as a mean change in the relative height of the dicrotic notch of -10.3% versus 0.0% after atenolol.


CONCLUSIONS
Future studies should clarify whether the vasoactive profile of carvedilol may translate into reduced occurrence of cold hands and feet amongst patients treated for hypertension.
Klemsdal
T O
TO
Ulleval University Hospital, Department of Cardiology, Norway.
Mundal
H H
HH
Gjesdal
K
K
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000328:Adult; D001262:Atenolol / Q000494:pharmacology*; D001775:Blood Circulation / Q000187:drug effects*; D001831:Body Temperature / Q000187:drug effects*; D002227:Carbazoles / Q000494:pharmacology*; D000077261:Carvedilol; D005385:Fingers / Q000098:blood supply; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007035:Hypothermia / Q000503:physiopathology*; D008297:Male; D010991:Plethysmography; D011412:Propanolamines / Q000494:pharmacology*
D000319:Adrenergic beta-Antagonists; D002227:Carbazoles; D011412:Propanolamines; D000077261:Carvedilol; D001262:Atenolol