Long-term outcome after coronary artery bypass grafting in patients with severe left ventricular dysfunction.

BACKGROUND

The aim of this study was to define the potential for long-term survival with severe left ventricular dysfunction after coronary bypass and to quantify any improvement in overall functional status.

METHODS

Left ventricular dysfunction was confirmed preoperatively and the long-term survival and functional outcome after bypass was determined by follow-up studies obtained during the span of a decade.

RESULTS

From 1/1990 to 12/1999, 86 patients with severe left ventricular dysfunction (mean ejection fraction, 0.18 +/- 0.03; range, 0.10 to 0.20) underwent coronary artery bypass grafting. There were 10 perioperative deaths (11% mortality). The mean survival was 55 months (standard deviation +/- 34 months; range, 2 to 141 months) with an actual 5-year survival rate of 59% (actuarial 5-year 65%, 10-year 33%). Echocardiography obtained between 1 and 6 months, 6 months and 1 year, 1 and 2 years, 2 and 4 years, 4 and 6 years, and 6 and 11 years showed the ejection fraction improved to 0.29 +/- 0.08 (p < 0.001), 0.31 +/- 0.14 (p < 0.002), 0.35 +/- 0.08 (p < 0.001), 0.27 +/- 0.10 (p = 0.002), 0.36 +/- 0.14 (p = 0.004), and 0.30 +/- 0.11 (p = 0.004), respectively. At 1 to 6 months, 6 months to 1 year, and 1 to 2 years, the diastolic left ventricular dimension was unchanged, but the systolic left ventricular dimension decreased significantly from 5.02 +/- 0.77 cm to 4.26 +/- 0.91 cm (p = 0.046), 3.98 +/- 1.43 cm (p = 0.08), and 4.10 +/- 1.14 cm (p = 0.07). The preoperative New York Heart Association classification for all patients improved from 2.8 +/- 0.8 to 1.6 +/- 0.7 (p < 0.001) after a mean of 53 months (standard deviation +/- 34 months).

CONCLUSIONS

Patients with severe left ventricular dysfunction can derive long-term benefit from coronary bypass through improved left ventricular contractility as documented by a significantly decreased systolic left ventricular dimension and increased ejection fraction. Successful bypass is associated with a 59% actual 5-year survival rate and significantly improved New York Heart Association functional class.