Effects of angiotensin-converting enzyme inhibition on transient ischemia: the Quinapril Anti-Ischemia and Symptoms of Angina Reduction (QUASAR) trial.
OBJECTIVE
We sought to determine whether angiotensin-converting enzyme inhibition (ACE-I) (i.e., quinapril) prevents transient ischemia (exertional and spontaneous) in patients with coronary artery disease (CAD).


BACKGROUND
It is known that ACE-I reduces the risk of death, myocardial infarction (MI), and other CAD-related outcomes in high-risk patients. Numerous studies have confirmed that ACE-I improves coronary flow and endothelial function. Whether ACE-I also decreases transient ischemia is unclear, because no studies have been adequately designed or sufficiently powered to evaluate this issue.


METHODS
Using a randomized, double-blinded, placebo-controlled, multicenter design, we enrolled 336 CAD patients with stable angina. None had uncontrolled hypertension, left ventricular (LV) dysfunction, or recent MI, and all developed electrocardiographic (ECG) evidence of ischemia during exercise. They were randomly assigned to one of two groups: 40 mg/day quinapril (n = 177) or placebo (n = 159) for 8 weeks. Patients then entered an additional eight-week treatment phase to examine the full dose range. Those assigned to 40 mg quinapril continued that dose and those assigned to placebo were titrated to 80 mg/day. Treadmill testing, the Seattle Angina Questionnaire, and ambulatory ECG monitoring were used to assess responses at baseline and at 8 and 16 weeks.


RESULTS
The groups did not differ significantly at entry or in terms of indexes assessing myocardial ischemia at 8 or 16 weeks of treatment. In this low-risk population, ACE-I was not associated with serious adverse events.


CONCLUSIONS
Our findings suggest short-term ACE-I in CAD patients without hypertension, LV dysfunction, or acute MI is not associated with significant effects on transient ischemia.
Pepine
Carl J
CJ
University of Florida College of Medicine, Division of Cardiovascular Medicine, Gainesville, Florida 32610-0277, USA. pepincj@medicine.ufl.edu
Rouleau
Jean-Lucien
JL
Annis
Karen
K
Ducharme
Anique
A
Ma
Patrick
P
Lenis
Jacques
J
Davies
Richard
R
Thadani
Udho
U
Chaitman
Bernard
B
Haber
Harry E
HE
Freedman
S Ben
SB
Pressler
Milton L
ML
Pitt
Bertram
B
D000787:Angina Pectoris / Q000517:prevention & control*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D003324:Coronary Artery Disease / Q000188:drug therapy; D004311:Double-Blind Method; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000517:prevention & control*; D000077583:Quinapril; D044005:Tetrahydroisoquinolines / Q000627:therapeutic use*
D000806:Angiotensin-Converting Enzyme Inhibitors; D044005:Tetrahydroisoquinolines; D000077583:Quinapril