Operative Myocardial Protection in Patients with Left Ventricular Hypertrophy: The Role of Systemic Hypothermia.

OBJECTIVES: Myocardial hypertrophy represents a great challenge in cardiac surgery. Several strategies have been described to protect the hypertrophied myocardium during cardiopulmonary bypass, and aortic clamping, yet the ideal strategy has not been identified. This study investigates the use of moderate systemic hypothermia (MSH) as an adjuvant method to protect the hypertrophied myocardium in patients undergoing aortic valve replacement (AVR).

METHODS: Twenty eight patients undergoing AVR were divided into two groups, (Group I) received continuous cold 5-8 °C retrograde blood cardioplegia (CRBC) and their body temperature was cooled down to 23-26 °C. (Group II) also received CRBC but their body temperature was kept at 32-34 °C.

RESULTS: No operative morality (30 days) was noted in both groups. Postoperative reduction in ejection fraction (EF) was seen in nine patients of group I and in twelve patients of group II (P < 0.05). The need for multiple inotropes was more in group II (eight patients) than in group I (two patients) (P < 0.001). IABP was needed in three patients of group II and non in group I (P < 0.01).

CONCLUSION: Moderate systemic hypothermia might have a role in protecting hypertrophied myocardium in patients undergoing AVR.