G. Dangas et al., The effect of early postinfarction revascularization of asymptomatic patients on left ventricular remodeling, CORON ART D, 10(4), 1999, pp. 203-210
Background Patients with angina after a Q-wave myocardial infarction benefi
t from elective revascularization, but it is not known whether asymptomatic
patients, including those with a totally occluded infarct-related artery,
improve after revascularization.
Objective To determine the effect of early postinfarction revascularization
of asymptomatic patients on left ventricular remodeling.
Methods We prospectively studied 31 consecutive asymptomatic patients (aged
57+/-2 years, 24 with anterior infarcts) after Q-wave myocardial infarctio
n with greater than or equal to 70% stenosis of the infarct-related artery
(IRA) who underwent early elective revascularization (days 4-10 after myoca
rdial infarction). Group I consisted in patients with a totally occluded IR
A (n = 10), and group II consisted in patients with a patent, though stenos
ed, IRA (n = 21). Resting echocardiography and low-dose dobutamine echocard
iography were performed at baseline (day 3 +/- 1), and rest echocardiograph
y was repeated after an 8-week follow-up. Significant myocardial viability
was defined as greater than or equal to 2 wall segments improved (in a 16-s
egment model of left ventricle) versus baseline, and significant functional
recovery as greater than or equal to 2 segments improved versus baseline o
n follow-up examination. Left ventricular end-systolic volume indices (ESVI
) and end-diastolic volume indices and ejection fractions were measured by
using a modified version of Simpson's rule (using apical two-chamber and fo
ur-chamber views).
Results The left ventricular ESVI of patients in group I had decreased by 4
.2 +/- 1.9 ml/m(2), whereas for patients in group II the left ventricular E
SVI had increased by 4.2 +/- 1.7 ml/m(2) (P=0.006). Similarly, the left ven
tricular end-diastolic volume index had decreased by 0.7 +/- 2.4 ml/m(2) ve
rsus baseline at follow-up for patients in group I and increased by 78 +/-
2.1 ml/m(2) for patients in group II (P=0.02). The left ventricular ejectio
n fraction increased by 73 +/- 3% for patients in group I and decreased by
0.4 +/- 2% for patients in group II (P=0.04).
Conclusion There is less global left ventricular remodeling, a potentially
deleterious process, after elective revascularization early after Q-wave my
ocardial infarction in asymptomatic patients who had had a totally occluded
IRA before revascularization than there is in patients who had already had
a patent, though stenosed, IRA before revascularization. These results sug
gest that restoration of patency of IRA after a Q-wave myocardial infarctio
n is beneficial even for asymptomatic patients. Coronary Artery Dis 10:203-
210 (C) 1999 Lippincott Williams & Wilkins.