Ventricular arrhythmia burden high among patients with BIVAD implants

Ventricular arrhythmias (VAs) occur frequently in patients with durable biventricular assist device (BIVAD) implants and worsens outcomes in these patients, according to a recent study.

“To our knowledge, this was the first study to specifically evaluate the prevalence and outcomes of VAs in patients with BIVADs with right-sided inflow cannula placed in the right atrial position,” said researchers. “The clinical significance and burden of atrial tachyarrhythmias after BIVAD placement was beyond the scope of this study and is an area for future research.”

The retrospective cohort study included 13 consecutive patients with BIVADs. Ten participants had contemporaneous device placement and the remaining three were converted from left ventricular assist devices (LVAD) alone. Six developed VA (median age, 54 years ;100 percent male) while seven did not (median age, 29 years; 71 percent male). [J Interv Card Electrophysiol 2019;doi:10.1007/s10840-019-00682-0]

The resulting incidence rate of VA was 46 percent. Patients who developed this outcome were significantly younger (p=0.035) and had lower right atrial pressure (13 vs 21 mmHg; p=0.04) and higher pulmonary artery pulsatility index (1.8 vs 1.0; p=0.016). All six VA participants also had a history of VA even before BIVAD implantation.

Forty-one episodes were reported in the six patients who developed VA. More than half of these (56 percent; n=23) were associated with the use of inotropes, while 12 percent, 7 percent and 5 percent were related to suction events, electrolyte derangements and thrombosis of a right ventricular assist device (RVAD), respectively. Eight episodes had no obvious trigger. A total of 62 interventions were delivered.

Notably, VAs were more likely to occur in the first month after BIVAD placement, with a median time to the first event of 14 days.

Major bleeding and hospital readmission were common adverse events observed after BIVAD implantation. Age-adjusted Poisson regression analysis found that the former occurred with significantly greater frequency in the VA group (mean ratio, 3.049, 95 percent confidence interval, 1.073–8.664; p=0.036). No such effect was reported for the readmissions or for other adverse events, such as RVAD thrombosis, infections, and renal and respiratory failures.

Kaplan-Meier curves additionally showed rapid divergence of the trajectories of event-free survival in favour of the non-VA patients (p=0.046).

“There are three key findings in this study,” the researchers said. “First, the prevalence of VAs during BIVAD therapy was high, but similar to a propensity-matched LVAD population. Second, BIVAD patients with VAs experienced more major bleeding and had worse composite postoperative cardiovascular morbidity compared with BIVAD patients without VAs.”

“Third, the presence of VA was associated with worse outcomes, irrespective of BIVAD or LVAD therapy,” they added. Future studies should look at potential interventions, such as ablation, and evaluate their efficacies in improving patient outcomes in BIVAD patients who develop VA.