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Published on: March 27, 2018
Stroke and mortality rates after off-pump vs. pump-assisted/no-clamp coronary artery bypass grafting
George V Letsou1,2, Fadi I Musfee3, Qianzi Zhang1
1Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX, USA.
Insights
Minimally invasive coronary artery bypass grafting (CABG) techniques, including off-pump and pump-assisted no-clamp methods, achieve very low stroke rates. Avoiding aortic clamping is key to reducing CABG-related stroke risk, with similar mortality across techniques.
Area of Science:
- Cardiovascular Surgery
- Neurosurgery
- Anesthesiology
Background:
- Ascending aorta manipulation during on-pump coronary artery bypass grafting (CABG) increases stroke risk.
- Off-pump surgery and pump-assisted surgery without aortic clamping are strategies to mitigate this risk.
- This study compares the efficacy of these techniques in reducing stroke and perioperative mortality.
Approach:
- A retrospective review of 570 consecutive coronary artery bypass grafting procedures (June 2011-October 2017).
- Procedures included off-pump/no-bypass, pump-assisted/no-clamp, and combined techniques.
- Patient characteristics and outcomes (stroke, mortality) were analyzed by surgical approach.
Key Points:
- None of the pump-assisted/no-clamp patients experienced a stroke, compared to 0.3% for off-pump/no-bypass and 0.8% for combined techniques.
- Patients over 70, female, or with comorbidities were more likely to receive pump-assisted or combined procedures.
- Stroke and in-hospital mortality rates did not significantly differ between the techniques.
Conclusions:
- A hybrid approach utilizing off-pump, pump-assisted, and combined techniques yields very low stroke rates in coronary revascularization.
- Avoiding aortic clamping appears critical for reducing CABG-associated stroke.
- Off-pump/no-bypass surgery demonstrated no significant stroke reduction advantage over pump-assisted/no-clamp or combined methods.
Background:
Ascending aorta manipulation during on-pump coronary artery bypass grafting (CABG) surgery can release embolic matter and may cause stroke. Strategies for lowering the stroke rate associated with coronary artery bypass grafting surgery include off-pump surgery without cardiopulmonary bypass and pump-assisted surgery with minimal aortic manipulation (i.e., without aortic cross-clamping). We examined whether one approach is superior to the other in reducing stroke and perioperative mortality rates.
Methods:
We reviewed consecutive elective, urgent, and emergency off-pump/no-bypass and pump-assisted/no-clamp coronary artery bypass grafting procedures performed by a single surgeon at our institution from June 2011 through October 2017.
Results:
Of 570 patients analyzed, 395 (69.3%) underwent off-pump/no-bypass surgery, 43 (7.5%) underwent pump-assisted/no-clamp surgery, and 132 (23.2%) transitioned mid-procedure from off-pump/no-bypass to pump-assisted/no-clamp surgery. Patients who were >70 years old, were female, or had diabetes, cardiomegaly, or a history of myocardial infarction or congestive heart failure were more likely to undergo pump-assisted/no-clamp surgery or the combined technique. None of the pump-assisted/no-clamp patients had a stroke, versus 0.3% of the off-pump/no-bypass patients and 0.8% of the combination patients. Stroke and in-hospital mortality rates did not differ by technique.
Conclusions:
A hybrid strategy incorporating off-pump, pump-assisted, and combined off-pump/pump-assisted techniques achieved very low stroke rates in patients undergoing coronary revascularization. Perioperative mortality was similar for all three techniques. Avoiding aortic clamping may be crucial for decreasing CABG-related stroke rates. Off-pump/no-bypass surgery had no significant advantage over the pump-assisted/no-clamp or combined techniques in reducing the stroke rate after coronary artery bypass grafting surgery.
