Tolerance of Sustained Ventricular Fibrillation During Continuous-Flow Left Ventricular Assist Device Support

The widespread use of continuous-flow left ventricular assist devices for mechanical circulatory support has shown that long-term hemodynamic support is possible, even when a clinical “pulse” cannot be detected. We present the incidental discovery of ventricular fibrillation in 6 alert, hemodynamically stable patients supported only by a continuous-flow device (HeartMate II, n=5; Jarvik 2000, n=1). Ventricular fibrillation was found in 3 patients during routine outpatient follow-up visits and in 3 awaiting discharge from the hospital after device placement. Diagnosis was confirmed by electrocardiographic and echocardiographic studies. The average duration of mechanical circulatory support before ventricular fibrillation occurred was 221 ± 362 days (range, 5–864 d). All patients were conscious and ambulatory at the time of the arrhythmia. Three patients reported symptoms—primarily fatigue, nausea, and exertional dyspnea—that prompted evaluation. Serum chemistry analysis of blood drawn immediately after dia...