Continuous flow ventricular assist devices do not worsen GI bleeding risk

The use of continuous flow ventricular assist devices (VADs), regardless of the type, does not appear to exacerbate the risk of gastrointestinal bleeding (GIB), according to a recent meta-analysis.

Researchers retrieved five studies from online databases, selecting only randomized controlled trials and observational studies. The cumulative sample eligible for quantitative analysis consisted of 1,853 participants who received either centrifugal flow (CF) or axial flow (AF) VADs. Overall quality was adequate, with a minimum score of seven out of a total nine stars in the Newcastle-Ottawa Scale.

The occurrence of GIB was comparable between the two device types, although statistical significance was nearly achieved (odds ratio [OR], 0.81, 95 percent confidence interval [CI], 0.65–1.00; p=0.05) in favour of CF-VAD.

This borderline-significance was driven by one study, which found that the AF devices triggered more GIB events than the CF comparators (OR, 0.74, 95 percent CI, 0.56–0.97; p=0.03).

The between-study variance in the meta-analysis was 0±0.06, and the variation in the estimated effect sizes was lower than expected. Egger’s regression test was not significant. Nevertheless, the researchers said that the small number of studies included could have weakened the statistical power of the tests in the meta-analysis.

“Regardless of the type of continuous flow VAD used, GIB continues to be a major challenge in these patients. We recommend that more research should be conducted on this topic to aid the feasibility of a broader meta-analysis,” researchers said. “Data on outcomes should be explicitly outlined and possible confounding factors should be controlled.”