Intermittent antegrade warm blood cardioplegia in aortic valve replacement.

BACKGROUND: Intermittent antegrade warm blood cardioplegia (IAWBC) is a well established technique of myocardial protection for coronary artery surgery, with metabolic and experimental basis.

METHODS: To evaluate its effectiveness in aortic valve replacement (AVR), we compared 171 consecutive patients who underwent first AVR using IAWBC (group A) with the last 100 consecutive patients who underwent first AVR using intermittent antegrade cold blood cardioplegia (IACBC) (group B). The endpoints considered were myocardial protection related (recovery of spontaneous rhythm, need for mechanical support, incidence of low-output syndrome, perioperative Q wave myocardial infarct, CK-MB levels, ventricular arryhthmias and lidocaine infusion requirement, cardiac-related deaths, and deaths any cause) and temperature perfusion related (bleeding, awaking time, time to extubation, and cerebrovascular accidents).

RESULTS: Mortality was similar in both groups, but no patient in group A died for cardiac-related cause (0 vs 4, p < 0.01). More patients in group A recovered a spontaneous rhythm (144 vs 47, p < 0.0001). Incidence of low-output syndrome was higher in group B (16 vs 3, p < 0.0005), as well as ventricular arryhthmias incidence and need for lidocaine infusion (respectively 15 vs 2, p < 0.0001, and 10 vs 1, p < 0.0005). Awaking time was shorter in warm patients (2.5 +/- 2.5 hours vs 4.4 +/- 3.7 hours, p < 0.0005), as the extubation time (9.4 +/- 7.7 hours vs 13.5 +/- 11.7 hours, p < 0.0005) and bleeding (803 +/- 714 mL/24 hours vs 1051 +/- 1375 mL/24 hours, p < 0.05). As a consequence, the intensive care unit and the postoperative hospital stays were shorter in group A (32 +/- 27 hours vs 48 +/- 20 hours, p < 0.0005, and 7.2 +/- 3.1 days vs 11.3 +/- 5.4 days, p < 0.0001, respectively).

CONCLUSIONS: IAWBC provides lower cardiac-related mortality and morbidity in patients who undergo AVR in comparison with IACBC.