Key Points
- To assess resting and exercise left ventricular function following coronary artery bypass grafting in patients with prior myocardial infarction and evaluate positron emission tomography for identifying reversible ischemic myocardium.
- Evaluated 23 patients with established prior myocardial infarction and severely depressed preoperative left ventricular function (ejection fraction < 45%).
- Performed echocardiography and heart catheterization pre- and postoperatively, alongside preoperative rubidium-82 and fluorodeoxyglucose positron emission tomography.
- In 21 patients with patent grafts, coronary artery bypass grafting significantly increased resting ejection fraction from 34% ± 14% to 52% ± 11% and exercise ejection fraction from 31% ± 14% to 58% ± 13% (P < 0.01).
- The time constant of diastolic relaxation was significantly shortened after revascularization, whereas ejection fraction remained unchanged in 2 patients with pathological graft findings.
- Contractility improvements occurred selectively in regions displaying exercise-induced ischemia preoperatively and in areas demonstrating metabolic mismatch on positron emission tomography.
Structured PICO
Does surgical revascularization improve left ventricular function in patients with previous myocardial infarction and impaired preoperative LV function?
PPopulation23 patients with established previous myocardial infarction and impaired preoperative left ventricular function (EF < 45%)
IInterventionCoronary artery bypass grafting (CABG) with preoperative positron emission tomography (PET) assessment
OOutcomePostoperative left ventricular function (ejection fraction) at rest and during exercisesurrogate
Surgical revascularization significantly improves both resting and exercise left ventricular ejection fraction in patients with prior myocardial infarction and viable myocardium.