Randomized study of right ventricular function with intermittent warm or cold cardioplegia

Area of Science:

• Cardiovascular Surgery
• Cardiac Anesthesia
• Myocardial Protection

Background:

• Transient right ventricular dysfunction is a known complication after bypass operations, even with cold blood cardioplegia.
• Intermittent warm blood cardioplegia is used for visualization during distal anastomoses, but its effect on right ventricular function is unclear.

Purpose of the Study:

• To evaluate the impact of intermittent antegrade warm blood cardioplegia versus cold blood cardioplegia on postoperative right ventricular function.

Main Methods:

• 52 patients undergoing isolated bypass grafting were randomized to receive either intermittent warm or cold blood cardioplegia.
• Postoperative right ventricular ejection fraction and volume indices were assessed using rapid-response thermodilution catheter.
• Groups were compared based on age, sex, ventricular function, and coronary stenoses.

Main Results:

• Patients receiving warm cardioplegia demonstrated a significantly greater right ventricular ejection fraction at 6 and 8 hours postoperatively.
• The right ventricular end-diastolic volume index was lower in the warm cardioplegia group 8 hours after surgery.
• No significant differences were observed in pulmonary arterial pressures or right ventricular stroke work index between groups.

Conclusions:

• Warm blood cardioplegia, despite periods of normothermic ischemia, effectively maintains right ventricular hemodynamics following bypass grafting.
• This suggests warm cardioplegia may offer improved right ventricular protection compared to cold cardioplegia.