Fractal or biologically variable delivery of cardioplegic solution prevents diastolic dysfunction after cardiopulmonary bypass
Methods: Invasive monitors and sonomicrometry crystals were placed, and cardiopulmonary bypass was initiated. The aorta was crossclamped, and cold blood cardioplegic solution was infused intermittently through the aortic root with either conventional cardioplegia (n = 8) or biologically variable pulsatile cardioplegia (n = 8; mean pressure, 75 mm Hg for 85 minutes). The crossclamp was released, cardiac function was restored, and separation from cardiopulmonary bypass was completed. With stable temperature and arterial blood gases, hemodynamics and systolic and diastolic indices were compared at 15, 30, and 60 minutes after cardiopulmonary bypass.
Results: Diastolic stiffness doubled from 0.027 ± 0.016 mm Hg/mm (mean ± SD) at baseline to 0.055 ± 0.036 mm Hg/mm (P = .003) at 1 hour after bypass in group CC, associated with increased left ventricular
Conclusion: Diastolic cardiac function is better preserved after cardiopulmonary bypass with biologically variable pulsatile cardioplegia and fractal perfusion. This may be attributed to enhanced microcirculatory perfusion with improved myocardial protection. A model supporting these results is presented.