Evaluation of left ventricular function in coronary bypass surgery

Area of Science:

• Cardiology
• Cardiac Surgery
• Echocardiography

Background:

• Assessing left ventricular (LV) systolic and diastolic function is crucial in cardiac surgery patients.
• Non-invasive methods are preferred for perioperative monitoring.
• Preoperative ejection fraction (EF) and end-diastolic pressure (EDP) are commonly used indicators.

Purpose of the Study:

• To evaluate non-invasive indexes for measuring systolic and diastolic ventricular function.
• To assess the predictive ability of preoperative EF and EDP for LV function post-coronary artery bypass grafting (CABG).

Main Methods:

• End-systolic elastance (Ees) was measured perioperatively using transesophageal echocardiography and arterial pressure monitoring.
• Diastolic function was assessed using three echocardiography/Doppler indexes.
• Caval balloon occlusions were used to induce preload variations for Ees assessment.

Main Results:

• A significant positive correlation was observed between preoperative EF and perioperative Ees (r = 0.69, p = 0.03).
• Ees significantly decreased after cardiopulmonary bypass (p < 0.001), indicating systolic stunning.
• No significant correlations were found between preoperative EDP and non-invasive diastolic indexes.

Conclusions:

• Preoperative EF is a reliable predictor of intraoperative systolic function.
• Semi-invasive Ees is a promising tool for monitoring LV systolic function and detecting perioperative stunning after bypass.
• Current non-invasive diastolic function assessment methods require further refinement for perioperative use.