LVAD-specific infections common after heart transplant

While left ventricular assist device (LVAD)-specific infections (LSI) are common among patients undergoing heart transplant (HTs), they seem to have no impact on postsurgical outcomes, according to a recent study.

“To our knowledge, our study represents one of the largest single-centre contemporary cohorts studying the impact of LSI on post-HT outcomes,” the researchers said. “The vast majority of LSIs were attributed to driveline infections, and there was an equal distribution of gram-positive and gram-negative organisms.”

The retrospective analysis included 111 HT patients (median age 56 years, 80 percent men) who received LVAD support. More than half (57 percent; n=63) of the participants had a history of LSI. These patients were more likely to have a higher urgency status (p<0.001), have greater body surface area (p=0.018), and have a history of tobacco use (p=0.05).

Most LSIs were driveline infections (n=59; 93.7 percent). Only two cases (3 percent) were of pump-pocket infections, while the last remaining patient had sternal wound infection. Gram-positive and gram-negative organisms were cultured from 41.3 percent and 42.9 percent of LSI patients, respectively, with only 13 percent (n=8) having polymicrobial infections. Two patients had no identifiable organism. [Am J Cardiol 2021;160:67-74]

Almost all LSI patients (97 percent; n=61) were on antibiotic medication at the time of LSI, with 57 percent and 40 percent being on oral and intravenous agents, respectively.

Despite such prevalence, LSI did not seem to have a significant impact on outcomes. Of the 111 HT patients, 28 percent (n=31) reached the primary composite outcome of 30-day death, allograft rejection, or acute renal failure (ARF), with no significant difference between those with vs without LSIs (30 percent vs 25 percent; p=0.55).

Extending the follow-up to 1-year likewise showed that the composite endpoint occurred at a comparable rate between patients with vs without LSI (38 percent vs 40 percent; p=0.87). Similarly, median length of stay in the ICU (p=0.79) and in the hospital (p=0.82) did not differ according to infection status.

Adjusted linear regression analysis further confirmed that LSI was not associated with the primary composite outcome (odds ratio, 0.75, 95 percent confidence interval, 0.29–1.95).

“Our findings suggest that LSIs do not appear to negatively affect post-transplant outcomes. However, LSIs continue to contribute significantly to morbidity for patients on LVAD support,” the researchers said.

“Ongoing clinical care and research efforts are needed to further elucidate the most effective methods to prevent and treat LSIs,” they added.

Important study limitations included its retrospective, single-centre, nonrandomized design, which might have contributed to selection bias and introduced additional confounding. The small number of patients could also limit the study’s power to detect small statistical differences.