Coronary artery response to cold-pressor test is impaired early after operation in heart transplant recipients.
OBJECTIVE
The aim of the present study was to evaluate the coronary vasomotor response to the cold-pressor test within 3 months after heart transplantation.


BACKGROUND
Normal epicardial coronary arteries dilate in response to sympathetic stimulation evoked by the cold-pressor test. In transplant recipients, abnormal coronary vasomotion has been described shortly after operation.


METHODS
Fourteen heart transplant recipients were compared 52 +/- 15 days (mean +/- SD) after operation with 10 control subjects. All had angiographically normal epicardial coronary arteries. Coronary blood flow velocity was measured with a Doppler catheter placed in the proximal left anterior descending coronary artery. Four segments in each patient were analyzed by quantitative coronary angiography to assess the diameter changes during the cold-pressor test and after intracoronary injection of isosorbide dinitrate.


RESULTS
Coronary flow velocity increased similarly during the cold-pressor test in control subjects and in transplant recipients, from 7.5 +/- 2.3 to 11.0 +/- 3.9 cm/s and from 10.3 +/- 3.2 to 13.7 +/- 4.8 cm/s (both p < 0.01). In control subjects, 39 of 40 segments analyzed dilated during the cold-pressor test. In transplant recipients, 48 of 56 segments analyzed did not change or constricted. The mean epicardial coronary diameter increased significantly during the cold-pressor test in control subjects (+13 +/- 6%, p < 0.001), whereas it did not change significantly in transplant recipients (-2 +/- 9%, p = NS). In transplant recipients, isosorbide dinitrate elicited coronary vasodilation similar to that in control subjects.


CONCLUSIONS
These data indicate that in human transplanted denervated hearts, coronary vasodilation in response to sympathetic stimulation by cold exposure is impaired shortly after operation.
Benvenuti
C
C
Service de Chirurgie Cardiaque, Centre Hospitalier et Universitaire Henri Mondor, Creteil, France.
Aptecar
E
E
Mazzucotelli
J P
JP
Jouannot
P
P
Loisance
D
D
Nitenberg
A
A
D000328:Adult; D003080:Cold Temperature; D017023:Coronary Angiography / Q000379:methods; D003326:Coronary Circulation / Q000187:drug effects / Q000502:physiology*; D003327:Coronary Disease / Q000175:diagnosis* / Q000503:physiopathology; D003331:Coronary Vessels / Q000187:drug effects / Q000503:physiopathology*; D005260:Female; D016027:Heart Transplantation / Q000502:physiology*; D006801:Humans; D007548:Isosorbide Dinitrate; D008297:Male; D008875:Middle Aged; D014661:Vasoconstriction / Q000502:physiology; D014664:Vasodilation / Q000502:physiology
D007548:Isosorbide Dinitrate