Normal survival curve after coronary artery bypass

Area of Science:

• Cardiovascular Surgery
• Cardiac Surgery Outcomes
• Long-term Follow-up Studies

Background:

• Coronary artery bypass grafting (CABG) is a common treatment for coronary artery disease.
• Understanding long-term patient outcomes is crucial for surgical decision-making and patient counseling.
• Previous studies have focused on short-to-medium term results, with less data on outcomes beyond 5-10 years.

Purpose of the Study:

• To evaluate the long-term survival and clinical outcomes of patients undergoing isolated coronary artery bypass surgery.
• To assess the incidence of angina, myocardial infarction, and repeat revascularization procedures over time.
• To compare the survival rates of patients with single, double, and triple vessel disease to age- and sex-matched normal populations.

Main Methods:

• Analysis of a consecutive series of 2,628 patients who underwent isolated CABG.
• Long-term follow-up totaling 13,915.5 patient-years.
• Actuarial survival analysis comparing patient survival to expected survival in the general population, stratified by disease severity (single, double, triple vessel disease).

Main Results:

• Survival without angina decreased from 81% at 1 year to 36.9% at 9 years post-CABG.
• Annual rates for nonfatal myocardial infarction and repeat CABG were 3.1% and approximately 1%, respectively.
• Five-year survival ratios compared to normal populations were 1.03 (single), 1.00 (double), and 1.00 (triple vessel disease).
• Ten-year survival ratios were 1.13 (single), 0.99 (double), and 0.85 (triple vessel disease).
• Cardiac causes constituted a significant proportion of deaths, particularly in double (68.9%) and triple vessel disease (65.7%) patients.

Conclusions:

• Isolated CABG provides excellent early survival, but long-term outcomes are characterized by a progressive decline in angina-free survival.
• The risk of cardiac events and the need for repeat revascularization increase over time.
• While survival remains comparable to the general population in the medium term for less severe disease, long-term survival, especially for triple vessel disease, shows a decline, with cardiac causes being the predominant reason for mortality.