Prospective analysis of bleeding events in left ventricular assist device patients.

BACKGROUND: Bleeding is a major cause of morbidity in patients with continuous flow left ventricular assist devices (LVADs). We sought to identify clinical predictors of bleeding within the first year of LVAD implantation. METHODS: A prospective study was performed on 30 patients with HeartMate II implantation at the University of Rochester Medical Center, Rochester, New York, United States. Blood was collected within 1 week before implantation, and at 1, 3, and 30 ± 10 days after implantation. Blood samples were analyzed for prothrombin time (PT), international normalized ratio (INR), von Willebrand factor (vWF) activity, vWF antigen, vWF multimers, collagen binding assay, factor VIII, and epinephrine closure time. The first bleeding event within 1 year of implantation was recorded. RESULTS: There were 17 (57%) patients with a bleeding event. The cumulative incidence of bleeding was 50% at 304 days. Age at the time of LVAD implantation was associated with higher risk of bleeding (hazard ratio (HR) = 1.05, 95% confidence interval (CI) = 1.01-1.10, p = 0.013). Higher baseline INR was also associated with increased risk of bleeding after adjusting for age at the time of implant (HR = 6.58, 95% CI = 1.21-35.70, p = 0.028). The bleeders and non-bleeders had similar hemostatic markers at all four time points. Prior to LVAD, mean epinephrine closure time was similar between bleeders and non-bleeders. However, post LVAD measurement of epinephrine, closure time was frequently limited by platelet clumping. CONCLUSION: Older age and baseline INR are associated with higher risk of bleeding in LVAD patients. Platelet clumping may suggest underlying platelet dysfunction and associated high risk of bleeding.

Perioperative hypertension: defining at-risk patients and their management.

Hypertension is an extremely pervasive condition that affects a large percentage of the world population. Although guidelines exist for the treatment of the patient with elevated blood pressure, there remains a paucity of literature and accepted guidelines for the perioperative evaluation and care of the patient with hypertension who undergoes either cardiac or noncardiac surgery. Of particular importance is defining the patients most vulnerable to complications and the indications for immediate and rapid antihypertensive treatment and/or cancellation of surgery to reduce these risks in each of the three perioperative settings: preoperative, intraoperative, and postoperative. This review also examines the parenteral antihypertensive medications most commonly administered in the perioperative setting.