Food and Drug Administration Malfunction Recalls of Left Ventricular Assist Devices

Left ventricular assist device exchange: a review of indications, operative procedure, and outcomes

The use of left ventricular assist devices (LVADs) is intended to treat patients with end-stage heart failure. Owing to technological advances, these devices are becoming more durable. However, LVADs may need to be exchanged when complications arise and heart transplantation is not possible. Indications for LVAD exchange (LVADE) include device thrombosis, device infections, and pump component failure. LVADE has historically been associated with a high risk of morbidity and mortality. In this review, we discuss the indications of LVADE, the decisional and technical aspects during surgery, and outcomes.

Mechanical Device Malfunction of the HeartMate II Versus the HeartMate 3 Left Ventricular Assist Device: The Rotterdam Experience

Mechanical device malfunction remains a known issue in left ventricular assist devices (LVADs). We investigated the incidence of mechanical device malfunction in the HeartMate II and HeartMate 3 LVADs. We conducted a retrospective study of all HeartMate II and HeartMate 3 LVADs implanted in our center. We evaluated major malfunction, potential major malfunction, minor malfunction, and need of device exchange. In total, 163 patients received an LVAD; in 63 (39%) a HeartMate II, and in 100 (61%) a HeartMate 3, median support time of respectively 24.6 months (interquartile range [IQR]: 32.4) and 21.1 months [IQR: 27.2]. Mechanical device malfunction, consisting of both major and potential major malfunction, occurred significantly less in the HeartMate 3 patients with a hazard ratio (HR) of 0.37 (95% confidence interval [CI]: 0.15-0.87, p = 0.022). Major malfunction alone occurred significantly less in HeartMate 3 patients with a HR of 0.18 (95% CI: 0.05-0.66, p = 0.009). HeartMate 3 patients had a significantly decreased hazard of a pump or outflow graft exchange (HR 0.13, 95% CI: 0.08-0.81, p = 0.008). System controller defects occurred significantly less in HM 3 patients ( p = 0.007), but battery-clips defects occurred significantly more in HM 3 patients ( p = 0.039). Major device malfunction including pump or outflow graft exchange occurred significantly less in HeartMate 3 compared to HeartMate II, while minor malfunctions were similar. Periodical assessment of the technical integrity of the device remains necessary during long-term LVAD support.

Outflow Graft Narrowing of the HeartMate 3 Left Ventricular Assist Device

BACKGROUND

Outflow graft narrowing has been reported in patients with the HeartMate 3 (HM3) left ventricular assist device (LVAD) due to accumulation of biodebris either internal or external to the graft. This study describes the prevalence, imaging findings, and clinical outcomes associated with HM3 LVAD outflow graft narrowing.

METHODS

A single-center retrospective cohort study was performed among patients who received a HM3 LVAD between 11/2014-7/2019. All patients with a Computed Tomography (CT) Angiography or CT with IV contrast sufficient to evaluate the outflow graft lumen were included. A narrowing was defined as a hypodensity of ≥3mm.

RESULTS

Of 165 HM3 LVAD patients, 46 (28%) had qualifying imaging. Outflow graft narrowing was present in 33% (15/46). One patient had complete obstruction requiring emergency surgery, while 14 had a median (interquartile range) hypodensity of 4.5 mm (3.3-5.8). The presence of outflow graft narrowing was significantly associated with longer duration of LVAD support (588.2±277.5 vs. 131.5±170.9 days, p<0.0001). One-year survival after identification of narrowing was 93%, with death occurring in one patient with complete obstruction. Left ventricular (LV) unloading (mean percent decrease in LV end diastolic diameter at time of CT imaging vs. pre-LVAD) was 16.7% vs 17.7% in patients with and without narrowing, respectively (p=0.86).

CONCLUSIONS

Among patients with adequate imaging, one-third have evidence of narrowing. Outflow graft narrowing due to biodebris was more likely to be found in HM3 LVAD patients with longer duration of LVAD support. There was no significant difference in LV unloading between patients with and without narrowing.