Atrial Fibrillation at Time of LVAD Implantation May Predict Poor Physical Performance 6 Months Later

The presence of atrial fibrillation at time of implantation of a full magnetically levitated left ventricular assist device (LVAD) was found to predict poor physical performance 6 months after implantation, according to findings from an analysis of the multicenter ELEVATE registry published in the Journal of Cardiac Failure.

This was an analysis of the data of 186 consecutive patients enrolled in the HeartMate 3 ELEVATE study (ClinicalTrials.gov identifier: NCT02497950) who completed a 6-minute walking test (6MWT) at 6 months after implantation of a LVAD. Another 8 patients who were unable to complete a 6MWT because of severe heart failure symptoms were also included.

Baseline parameters including sex, age, height, weight, therapy indication, comorbidities, blood chemistry, New York Heart Association (NYHA) class, echocardiographic findings, and Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profile were evaluated. The study’s primary outcome was the percentage of patients who were able to walk >300 meters during the 6MWT, 6 months after LVAD implantation.

At 6 months, 150 patients (77%) were able to walk >300 meters during the 6MWT, vs 44 patients (23%) who were not. Patients who walked ≤ 300 meters vs > 300 meters during the 6MWT were  older (59.5±10.4 vs 52.4±12.3 years, respectively; difference, -7.1 years; 95% CI, -11.2 to -3.1; P =.0006), were more often in NYHA class IV (63% vs 42%, respectively; P =.03), and more often had type 2 diabetes (43% vs 17%, respectively; difference, -25.9%; 95% CI, -41,7-10.0; P =.0004) at time of implantation.

A greater percentage of patients who walked ≤300 meters vs >300 meters during the 6MWT had a history of atrial fibrillation at time of implantation (57% vs 31%, respectively; difference, -26.2%; 95% CI, -42.5-9.8; P =.0015); they also  had lower levels of hemoglobin (8.0±1.5 vs 7.2±1.4 mmol/L, respectively; difference, 0.9; 0.4-1.4; P =.0008), and lower estimated glomerular filtration rate (71.7±27.2 vs 58.6±28.2 mL/min/m², respectively; difference, 13.1; 95% CI, 3.8-22.4; P =.0058).

A history of atrial fibrillation (odds ratio [OR], 3.22; 95% CI, 1.20-8.67), older age (OR for 10-year increment, 2.80; 95% CI, 1.55-5.07), NYHA IV (OR, 3.37; 95% CI, 1.27-8.98), and INTERMACS profile 1 to 2 (OR, 6.53; 95% CI, 1.92-22.19) were found to independently predict a 6MWD <300 meters in a multivariable regression analysis.

Limitations of this study included the exclusion of approximately 60% of the original cohort, many of whom were older and sicker than the included patients, and the lack information on postoperative rehabilitation, which could have affected patients’ physical capacity.

 “[Atrial fibrillation] prior to implantation appeared as an independent predictor of low 6MWD at 6 months post-implantation. This information is highly relevant in the evaluation of and communication with LVAD candidates in discussing realistic expectations in terms of physical capacity after the implantation,” noted the study authors.

Disclosure: This clinical trial was supported by Abbott. Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Gustafsson F, Mirza KK, Pya Y, et al. Predictors of physical capacity six months after implantation of a full magnetically levitated left ventricular assist device: An analysis from the ELEVATE registry [published online May 14, 2020]. J Card Fail. doi: 10.1016/j.cardfail.2020.04.004