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 undergone coronary artery bypass grafting (CABG). However, the prognostic 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 indexes may be useful to determine whether survival benefits are likely to be maintained or additional therapy should be considered.


RESULTS
To obtain information on factors related to long-term survival and cardiac events among elderly patients after CABG and, specifically, to determine the prognostic implications of left ventricular performance at rest and during exercise for predicting all causes of death, major nonsurgical cardiac events (death or myocardial infarction), and event-free or surgery-free survival, we evaluated the late postoperative course of 41 patients, aged 65 years and older, who had undergone 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 survival was 8.8 years after index radionuclide assessment. During follow-up 13 patients died with no known intercurrent event, five patients had nonfatal myocardial infarctions, and five underwent late (> or = 3 months after RNCA) repeat CABG or percutaneous transluminal coronary angioplasty. Log-rank comparisons of Kaplan-Meier product limit estimate curves identified only left ventricular ejection fraction at rest as significantly predictive of survival (p < 0.04). Patients with left ventricular ejection fraction at rest of less than 45% had a 7.8% average annual mortality risk, which was more than three times that of patients with normal resting function. Statistical trends also were found between mortality rates and completeness of revascularization (p < 0.06), major nonsurgical cardiac events and extent of anatomic disease (p < 0.08), and event-free or surgery-free survival and our index of completeness of revascularization (p = 0.08) and age at index RNCA (p < 0.07).


CONCLUSIONS
Assessment of left ventricular ejection fraction at rest is prognostically useful after CABG among elderly patients. The efficacy and timing of this approach should be confirmed in further investigations with larger and more varied patient subgroups.
Supino
P G
PG
Cardiology Division, Cornell University Medical College, New York, N.Y., USA.
Wallis
J B
JB
Chlouverakis
G
G
Borer
J S
JS
D000368:Aged; D017023:Coronary Angiography; D001026:Coronary Artery Bypass / Q000401:mortality; D015444:Exercise; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D011379:Prognosis; D011877:Radionuclide Imaging; D012306:Risk; D016277:Ventricular Function, Left