RISK STRATIFICATION IN THE ELDERLY PATIENT AFTER CORONARY-ARTERY BYPASS-GRAFTING - THE PROGNOSTIC VALUE OF RADIONUCLIDE CINEANGIOGRAPHY

Background. Recent data have shown that assessment of left ventricular function by radionuclide cineangiography (RNCA) predicts survival and cardiac events among non-age-selected patients who have previously un dergone coronary artery bypass grafting (CABG). However, the prognosti c value of this noninvasive approach is not known for elderly patients who now undergo CABG with progressively increasing frequency and who survive longer because of operation. Such easily applied prognostic in dexes may be useful to determine whether survival benefits are likely to be maintained or additional therapy should be considered. Methods a nd Results. To obtain information on factors related to long-term surv ival and cardiac events among elderly patients after CABG and, specifi cally, to determine the prognostic implications of left ventricular pe rformance at rest and during exercise for predicting all causes of dea th, major nonsurgical cardiac events (death or myocardial infarction), and event-free or surgery-free survival, we evaluated the late postop erative course of 41 patients, aged 65 years and older, who had underg one RNCA 1 month or more (mean 2.3 +/- 2.4 years; range 0.1 to 9 years ) after CABG. Average follow-up among patients with event-free surviva l was 8.8 years after index radionuclide assessment. During follow-up 13 patients died with no known intercurrent event, five patients had n onfatal myocardial infarctions, and five underwent late (greater than or equal to 3 months after RNCA) repeat CABG or percutaneous translumi nal coronary angioplasty. Log-rank comparisons of Kaplan-Meier product limit estimate curves identified only left ventricular ejection fract ion at rest as significantly predictive of survival (p < 0.04). Patien ts. with left ventricular ejection fraction at rest of less than 45% h ad a 7.8% average annual mortality risk, which was more than three tim es that of patients with normal resting function. Statistical trends a lso were found between mortality rates and completeness of revasculari zation (p < 0.06), major nonsurgical cardiac events and extent of anat omic disease (p < 0.08), and event-free or surgery-free survival and o ur index of completeness of revascularization (p = 0.08) and age at in dex RNCA (p < 0.07). Conclusions. Assessment of left ventricular eject ion fraction at rest is prognostically useful after CABG among elderly patients. The efficacy and timing of this approach should be confirme d in further investigations with larger and more varied patient subgro ups.