LAS VEGAS — Patients with elevated central venous pressure shortly after implantation with a continuous-flow left ventricular assist device were at increased risk for gastrointestinal bleeding in a study presented at the Heart Failure Society of America Annual Scientific Meeting.
Researchers conducted a retrospective, single-institution, two-arm cohort study in which they assessed 209 patients implanted with HeartMate II LVADs (Thoratec Corp.) at a single institution between August 2009 and October 2013.
The first arm of the study focused on GI bleeding and pulsatility index (PI), and included 185 HeartMate II recipients. Participants with a mean PI above the median for this group (n=90) were classified as having high PI, whereas those with a PI below the median (n=95) were identified as having low PI. The second arm focused on bleeding and central venous pressure (CVP) and included 173 HeartMate II recipients. Mean CVP at 2 and 3 days post-procedure was obtained for each patient; those with a mean CVP above the median for this group (n=86) were considered as having high CVP, those with CVP below the median (n=87) were identified as having low CVP.
The primary outcome for both arms of the trial was freedom from GI bleeding.
After a mean of 9 months of follow-up, no significant difference in incidence of GI bleeding was observed according to PI in the first arm of the trial. Patients with low PI experienced bleeding in 31% of cases vs. 29% in the high PI group (P=.6925). Secondary analysis in which patients were divided into tertiles according to PI yielded similar results.
The researchers noted a correlation between PI and pulse pressure at 2 and 3 days post-procedure (r=0.4511), suggesting that PI is a “modest, yet imperfect” indicator of pulsatility, Christopher T. Sparrow, MD, of Washington University in St. Louis, said during his presentation here.
In the second arm, after a mean follow-up of 12 months, patients with high CVP experienced bleeding in 40% of cases vs. 31% in the low CVP group (P=.0378). Dividing the group into tertiles according to CVP also indicated significantly increased rates of GI bleeding with increased CVP.
Sparrow said the differences between groups in the CVP arm were not apparent until after 90 days, suggesting that perioperative CVP may be a marker for long-term risk, rather than short-term, perioperative risk. This allows an opportunity to alter antithrombotic therapy early after implantation as needed to decrease future bleeding risk. Also, CVP measurement at different time points may be similarly useful for the prediction of GI bleeding risk, and that subsequent, separate analyses have supported this possibility.
“We believe prospective studies should be aimed at early identification of risk factors for bleeding, ideally in the preoperative or early postoperative setting, to allow alterations in antithrombotic therapy and potentially further patient education regarding the risks and benefits of LVAD support,” Sparrow said.
For more information:
Sparrow CT. Abstract #005. Jay N. Cohn New Investigator Physiology/Clinical Award. Presented at: the Heart Failure Society of American Annual Scientific Meeting; Sept. 14-17, 2014; Las Vegas.
Disclosure: Sparrow reported no relevant financial disclosures. Other investigators reported numerous financial disclosures.