Haemodynamic changes during beating heart coronary surgery with the 'Bristol Technique'

Area of Science:

• Cardiovascular Surgery
• Cardiac Anesthesia
• Hemodynamics

Background:

• Optimal exposure and stabilization of coronary arteries are crucial for precise anastomosis during off-pump coronary artery bypass (OPCAB) surgery.
• However, surgical manipulation can lead to significant hemodynamic deterioration, especially when grafting the circumflex (Cx) and posterior descending arteries (PDA).

Purpose of the Study:

• To assess the hemodynamic changes associated with positioning the beating heart for grafting the three main coronary arteries (left anterior descending - LAD, PDA, and Cx) during OPCAB surgery.

Main Methods:

• Twenty-nine patients undergoing OPCAB surgery were studied.
• Three surgical setups were used for LAD, PDA, and Cx anastomoses.
• Hemodynamic parameters were recorded at baseline and after each distal anastomosis with the heart in its anatomical position.

Main Results:

• No significant changes in heart rate (HR) or mean arterial pressure were observed across all setups.
• Grafting the LAD (setup 1) resulted in a decrease in stroke volume (SV) and an increase in pulmonary capillary wedge pressure (PCWP).
• Grafting the PDA (setup 2) and Cx (setup 3) led to more pronounced decreases in SV and cardiac index (CI), along with increases in central venous pressure (CVP), PCWP, pulmonary arterial pressure, and systemic vascular resistance index (SVRI).
• These hemodynamic changes were transient and resolved upon returning the heart to its anatomical position.

Conclusions:

• Exposure and stabilization of the three main coronary arteries during beating heart surgery do not cause significant changes in systemic blood pressure and HR.
• Transient hemodynamic deterioration during Cx and PDA distal anastomoses is well-tolerated, with no reported adverse clinical events.