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Early and long-term results of coronary artery bypass grafting with severely depressed left ventricular performance
Insights
Coronary artery bypass grafting (CABG) improved exercise left ventricular ejection fraction (LVEF) in patients with severe LV dysfunction. Some patients experienced significant LVEF improvement and remained asymptomatic long-term.
Area of Science:
- Cardiology
- Cardiac Surgery
- Cardiovascular Physiology
Background:
- Patients with disabling angina and severely depressed left ventricular (LV) performance often have poor long-term outcomes.
- The impact of coronary artery bypass grafting (CABG) on ventricular function in this specific patient group requires further investigation.
Purpose of the Study:
- To evaluate the effects of CABG on left ventricular (LV) performance and long-term clinical status in patients with severely depressed LV ejection fraction (EF).
- To identify predictors of improved ventricular function and clinical outcomes after CABG in this high-risk population.
Main Methods:
- Retrospective analysis of 18 patients with disabling angina and LV EF ≤27% who underwent CABG.
- Assessment of resting and exercise LV ejection fraction (LVEF), end-systolic volume (ESV), and end-diastolic volume (EDV) before and after CABG.
- Stratification of patients into two groups based on the change in peak exercise LVEF post-CABG.
Main Results:
- All patients survived CABG; one experienced perioperative myocardial infarction.
- No significant change in resting LVEF was observed.
- Peak exercise LVEF increased significantly (p<0.05) post-CABG.
- Patients with a greater increase in exercise LVEF (Group A) had better baseline LV function and smaller changes in ESV during exercise post-CABG.
- At 27 months post-CABG, 5 of 8 patients in Group A were asymptomatic.
Conclusions:
- CABG can improve exercise-induced left ventricular ejection fraction (LVEF) in patients with severely depressed LV function.
- Preoperative resting LVEF and exercise-induced changes in LV volumes may predict response to CABG.
- A subset of patients with severe LV dysfunction may achieve significant functional improvement and long-term asymptomatic status after CABG.
Abstract:
The effects of coronary artery bypass grafting (CABG) on ventricular performance and long-term clinical status were studied in 18 consecutive patients with disabling angina pectoris and severely depressed left ventricular (LV) performance (ejection fraction [EF] 27 +/- 9%). All patients survived CABG, although 1 patient had a perioperative myocardial infarction. There was no change in LVEF at rest, 29 +/- 12%, in the other 17 patients. However, LVEF during peak exercise increased from 22 +/- 7% to 27 +/- 14% (p less than 0.05). The 17 patients were separated into 2 groups: those who increased their peak exercise LVEF by at least 10% (group A, 8 patients) and those who increased it by less than 10% (group B, 9 patients). Preoperatively, patients in group A had a higher LVEF at rest (p less than 0.001) and smaller end-systolic and end-diastolic volumes at rest (p less than 0.001) and during exercise (p less than 0.005). Preoperatively, the LVEF in group A decreased with exercise, from 36 +/- 4% to 27 +/- 5% (p less than 0.01), but was unchanged in group B (19 +/- 3% vs 17 +/- 4%, difference not significant). After CABG, patients in group A had a smaller increase in end-systolic volume with exercise than those in group B (13 +/- 7 vs 34 +/- 22 ml/m2, p less than 0.05), but the changes in end-diastolic volume with exercise were not significantly different. At 27 +/- 5 months after CABG, 5 of 8 patients in group A were asymptomatic.(ABSTRACT TRUNCATED AT 250 WORDS)