Cor Vasa 2004, 45(12):575-580

Myocardial revascularization in patients with severe left ventricular systolic dysfunction

Martin Florian^3,*, Josef Kautzner¹, Jan Pirk², Ivan Málek¹

¹ Klinika kardiologie

² Klinika kardiovaskulární chirurgie, Institut klinické a experimentální medicíny

³ Centromed a. s., Praha, Česká republika

Objective:
Preoperative evaluation often does not allow an accurate prediction of postoperative outcome in patients with severe left ventricular (LV) systolic dysfunction who undergo coronary artery bypass grafting. The goal of this single-center study was to retrospectively analyze clinical risk factors that may predict perioperative mortality and long-term outcome in these high-risk patients.

Methods:
The study population consisted of 67 consecutive patients (60 males, mean age of 59.5 ± 8.0 years) with a preoperative left ventricular ejection fraction £ 20% who underwent surgical myocardial revascularization either alone or in a combination with another procedure during a seven-year period (January 1994 through December 2000). Predictors of perioperative and postoperative outcome were analyzed retrospectively (mean follow-up period of 63.7 ± 16.8 months).

Results:
Perioperative (30-day) mortality reached 9% (n = 6) and was higher in women, subjects with severe preoperative angina pectoris, perioperative low cardiac output syndrome and/or in patients requiring use of intraaortic balloon contrapulsation. The cumulative survival rates (Kaplan-Meier) at one, three and five years of the follow-up were 85%, 68% and 59%, respectively. Increased mortality during the follow-up was associated with the presence of extracoronary atherosclerosis, higher LV end-diastolic pressure, longer duration of extracorporeal circulation and aortic clamping time, forced use of intraaortic balloon pump and with a perioperative low cardiac output syndrome. Of these parameters, only time of extracorporeal circulation longer than 89 minutes (odds ratio 7.37) and presence of extracoronary atherosclerosis (odds ratio 4.28) were independent predictors of mortality. There was no difference in the outcome between patients with documented myocardial viability and those without preoperative viability testing. Statistical comparison of survival between patients with any form of ventricular tachyarrhythmia secondary prevention therapy and the rest of the patient cohort revealed a favorable prognosis in the former subgroup (10% vs. 45.6% mortality, p < 0.05).

Conclusions:
Our data confirm that surgical myocardial revascularization appears to be both a safe and effective therapeutic alternative in patients with severe systolic LV dysfunction. No difference in the postoperative outcome was revealed in patients with and without preoperative testing of myocardial viability. Complex arrhythmological evaluation and therapy may further improve postoperative prognosis in patients who have had previous spontaneous episodes of ventricular tachy-arrhythmias while other subjects may benefit from prophylactic implantable cardioverter-defibrillator implantation.

Keywords: Coronary artery bypass surgery; Left ventricular dysfunction; Myocardial viability

Published: December 1, 2004  Show citation