Changes in Systolic and Diastolic Ventricular Function with Cold Cardioplegic Arrest in Man

INTRODUCTION: Most of the cardiac surgery done today is performed with aortic cross-clamping and cardioplegic arrest. Despite improvements in cardioplegic techniques, ventricular dysfunction following cardioplegic arrest is a major cause of perioperative morbidity and mortality. This experiment will quantify the changes in left ventricular systolic function with cold cardioplegia. Four measures of cardiac function will be assessed with a volume conductance catheter. METHODS AND RESULTS: Thirty patients undergoing coronary artery bypass graft surgery had volume conductance and micromanometer catheters placed in their left ventricles. Preload reduction was used to measure Ees (the slope of the end-systolic pressure-volume relationship), EdP/dtMax-EDV (slope of dP/dtMax end-diastolic volume relationship), EPLRSW (slope of stroke work end-diastolic volume relationship), Eed (slope of the end-diastolic pressure-volume relationship), and ENegdP/dtMax-EDV (slope of the negative dP/dtMax end-diastolic volume relationship). Ees decreased from 4.32 +/- 2.94 prebypass to 2.52 +/- 1.06 mmHg/mL postbypass. CONCLUSION: Cold cardioplegic cardiac arrest is associated with postbypass systolic and diastolic ventricular dysfunction, which can be quantitated by volume conductance and micromanometer based measurements.