Continuous-Flow Left Ventricular Assist Device Implantation in Patients With a Small Left Ventricle.

BACKGROUND: Having a preoperative small left ventricle (LV) has been associated with higher complication and mortality rates after left ventricular assist device (LVAD) implantation; however, the outcomes after continuous-flow LVAD implantation have not been well studied. This is the first large-scale analysis of long-term survival after continuous-flow LVAD implantation in patients with a preoperative small LV.

METHODS: Our cohort comprised 511 patients who underwent primary implantation of a HeartMate II (n = 393 [Thoratec, Pleasanton, CA]) or HeartWare HVAD (n = 118 [HeartWare International, Framingham, MA]) at our institution between November 2003 and March 2016. Preoperative small LV was defined as having an LV end-diastolic diameter of 5.5 cm or less. HeartMate II and HVAD recipients with a small LV were compared with patients not having a small LV in terms of perioperative characteristics, complications, and long-term survival.

RESULTS: The HeartMate II was implanted in 393 patients (non-small LV, n = 352; small LV, n = 41), and the HVAD was implanted in 118 patients (non-small LV, n = 94; small LV, n = 24). For the HeartMate II recipients, the 24-month survival rate was 66.8% for the non-small LV patients and 56.1% for the small LV patients (p = 0.17); non-small LV patients had significantly better overall survival (p = 0.02). For the HVAD recipients, the 24-month survival rate was 71.3% for the non-small LV patients and 70.8% for the small LV patients (p = 0.96); these groups showed no significant difference in overall survival (p = 0.89).

CONCLUSIONS: Although the indications for implantation are different for these two devices, our study suggests that the survival advantage associated with HVAD implantation should be considered when selecting a device for small LV patients.