Failure to rescue: A candidate quality metric for durable left ventricular assist device implantation

Abstract

Objective: Failure to rescue (FTR), defined as death after a complication, is recognized as a principal driver of variation in mortality among hospitals. We evaluated FTR as a quality metric in patients who received durable left ventricular assist devices (LVADs) using the Society of Thoracic Surgeons Interagency Registry for Mechanically Assisted Circulatory Support.

Methods: Data on 13,617 patients who received primary durable LVADs from April 2012 to October 2017 at 131 hospitals that performed at least 20 implants were analyzed from the Society of Thoracic Surgeons Interagency Registry for Mechanically Assisted Circulatory Support. Rates of major complications and FTR were compared across risk-adjusted in-hospital mortality terciles (low, medium, high) and hospital volume. Logistic regression was used to estimate expected FTR rates on the basis of patient factors for each major complication.

Results: The overall unadjusted in-hospital mortality rate was 6.96%. Risk-adjusted in-hospital mortality rates varied 3.1-fold across terciles (low, 3.3%; high, 10.3%; P trend <.001). Rates of major complications varied 1.1-fold (low, 34.0%; high, 38.8%; P < .0001). Among patients with a major complication, 854 died in-hospital for an FTR rate of 17.7%, with 2.8-fold variation across mortality terciles (low, 8.5%; high, 23.9%; P < .0001). FTR rates were highest for renal dysfunction requiring dialysis (45.3%) and stroke (36.5%). Higher average annual LVAD volume was associated with higher rates of major complications (<10 per year, 26.7%; 10-20 per year, 34.0%; 20-30 per year, 34.0%; >30 per year, 40.1%; P trend <.0001) whereas hospitals implanting <10 per year had the highest FTR rate (<10 per year, 23.5%; 10-20 per year, 16.5%; 20-30 per year, 17.0%; >30 per year, 17.9%; P = .03).

Conclusions: FTR might serve as an important quality metric for durable LVAD implant procedures, and identifying strategies for successful rescue after complications might reduce hospital variations in mortality.

Keywords: LVAD; complications; failure to rescue; left ventricular assist device; mortality.

Figure 1.

CONSORT Diagram indicating selection of study patients. LVAD, Left Ventricular Assist Device. RVAD, Right Ventricular Assist Device

Figure 2.

A. Major complications and risk-adjusted in-hospital mortality by hospital. B. Failure to rescue and risk-adjusted in-hospital mortality by hospital. Major complication refers to any 1 or more of the following adverse events: severe postoperative acute right heart failure, device malfunction, stroke, respiratory failure requiring reintubation, renal dysfunction requiring dialysis, and major infection (pneumonia, bacteremia, mediastinitis, and sepsis), and major bleeding requiring reoperation. Failure to rescue was defined as the number of deaths among patients with any of the 7 major complications divided by the total number of patients with any of the 7 major complications.

Figure 3.

Rates of in-hospital mortality, major complications, and failure to rescue across risk-adjusted mortality terciles.

Figure 4.

Patients undergoing primary LVAD implantation were included in this retrospective study. There was a 3.1-fold difference in in-hospital mortality between low-mortality and high-mortality hospitals (3.3% vs. 10.3%, p<0.0001), yet there was a 1.1-fold difference in complications (34.0% vs. 38%, p<0.001) compared to a 2.8-fold difference in FTR (8.5% vs. 23.9%, p<0.0001). Higher mortality hospitals had a higher incidence of complications; however, the magnitude of variation in FTR was larger than the variation in complication rates. Lower annual LVAD volume was associated with fewer complications but higher FTR. LVAD, left ventricular assist device. FTR, failure to rescue.