Patients and Methods
Study design
This single-center, retrospective, observational study included patients
who underwent implantation of the HM3 LVAD between October 2017 and
March 2020. Data were collected prospectively and entered into an
institutional patient registry database. This study was approved by the
Ochsner Institutional Review Board (IRB), and all patients consented or
waived informed consent as per the IRB policy. To standardize our
approach and better compare the findings with HM3 trial results and
future studies, we used the standardized Mechanical Circulatory
Support-Academic Research Consortium (MCS-ARC) Adverse Events for
Outcomes and Adverse Events.11
Study population
Inclusion criteria for this study were 1) primary implantation with the
HM3 LVAD during the study period and 2) availability of 6-month
follow-up after LVAD implantation.
A total of 189 patients were implanted with the HM3 at our institution
from October 2017 to March 2020. Eighty-two patients were included in
the trial group (MOMENTUM 3 and CAP trials) and formed the comparator
group, while the remaining 107 patients were implanted after FDA
approval of the device (postapproval group). From these 107 patients,
102 patients met the primary HM3 implant criteria; the 5 excluded
patients were implanted with the HM3 as a replacement device for
previously placed durable mechanical devices. Of the 102 patients, 92
patients were selected for the final analysis because they had completed
6 months of follow-up (Figure 1).
Data collection
Patient baseline information included demographic details,
comorbidities, preoperative echocardiographic findings, preoperative
right heart catheterization pressures, INTERMACS profile, New York Heart
Association (NYHA) functional classification, indication for mechanical
support, and preoperative laboratory values. Adverse events within the
first 6 months of the implant were also collected.
Endpoints
The primary endpoint was survival at 6 months. Secondary endpoints
included freedom from pump thrombosis (requiring reoperation or pump
exchange) and other adverse events such as re-exploration for bleeding,
stroke, acute limb ischemia, gastrointestinal bleeding, driveline
infection, renal dysfunction requiring renal replacement therapy, and
right ventricular failure (RVF).
Statistical analysis
Categorical data are reported as frequencies and percentages and were
compared using the chi-square test. Continuous data are reported either
as mean ± standard deviation (SD) or median with interquartile range
(IQR) unless specified otherwise. Continuous data were compared using
the two-sided Wilcoxon-Mann-Whitney test. The log-rank test was used for
time-to-event analysis, with patient survival data presented as a
Kaplan-Meier survival curve up to 6 months from an implant date.
Patients were censored when they were transplanted. Statistical
significance was defined as p ≤0.05. The data were analyzed using
SAS/STAT software version 14.2 (SAS Institute Inc).