Left ventricular versus left atrial cannulation for the Thoratec ventricular assist device. In a retrospective study of 28 patients (23 men, 5 women) supported with ventricular assist devices greater than 3 days, the effect of LV cannulation versus LA cannulation on device performance was compared. Patients ranged in age from 12 to 67 years (mean 46 years) and were supported for 3-81 days (mean 15 years). Fifteen patients were supported with left VADs (6 LV and 9 LA), and 13 patients were supported with BVADs (5 LV and 8 LA). The mode of operation 91% of the time was the fill-to-empty mode. Ten data points were taken for each patient. LV cannulation results in higher VAD flow index at decreased preload, lower VAD systolic and vacuum pressures, and shorter diastolic durations. Eleven of the 28 patients survived. Although survival was greater in patients with LV cannulation, survival was more dependent upon reversibility of myocardial damage, eligibility for transplantation, or the development of complications. These data indicate that LV cannulation provides better VAD performance than LA cannulation in the fill-to-empty mode. 