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

Abstract

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 diagnosis showed no changes that suggested end-organ dysfunction. Three patients died of unrelated complications an average of 3.9 yr (range, 360–2,270 d) after the event. Two of the remaining 3 patients eventually underwent successful pump explantation, and one is on ongoing support. Our experience shows that it is possible for patients with continuous-flow left ventricular assist devices to remain hemodynamically stable while in ventricular fibrillation. Additional investigation is needed to determine whether defibrillator settings for these patients should be adjusted to limit delivery of shock therapy.

2019 EACTS Expert Consensus on long-term mechanical circulatory support

“…The burden of VA in LT-MCS recipients is high; preoperative VA is the major predictor of late postoperative VA. VA is reasonably tolerated by many patients supported by LT-MCS with a low risk of immediate haemodynamic collapse [436]. The role of implantable cardioverter defibrillators (ICDs) for primary prevention of sudden cardiac death is unclear in patients supported by LT-MCS [84, 437].…”

Ventricular Fibrillation in a Left Ventricular Assist Device Patient: Can the echocardiogram be misleading?

“…11,12 However, as seen in our case, it is very important to defibrillate even asymptomatic patients with ongoing VAs to sinus (or paced) rhythm as soon as possible, since their ability to maintain adequate hemodynamic stability remains tenuous and can lead to right ventricular failure due to prolonged dysrhythmia. 17 Noteworthy in our case was the presence of organized contractility and rhythmic opening of the mitral valve on echocardiogram despite ventricular fibrillation on ECG. While some cardiac motion and valve opening could be explained by the negative pressure generated by the device, ventricular fibrillation is generally thought to manifest as asynchronous ventricular activity.…”

Arrhythmia Management in Pediatric Patients with Ventricular Assist Devices

“…While patients were symptomatic, there was no evidence of end-organ dysfunction as a result of the ventricular arrhythmia. After restoration of sinus rhythm, there was no recurrence of the ventricular arrhythmia [42]. This suggests that there can be hemodynamic stability with left VAD support during episodes of ventricular arrhythmia.…”

“…Studies have demonstrated that some adult patients with continuous-flow VAD remain hemodynamically stable while in ventricular tachyarrhythmia including ventricular fibrillation [40,[42][43][44]. While patients were symptomatic, there was no evidence of end-organ dysfunction as a result of the ventricular arrhythmia.…”