Background: Left ventricular assist devices (LVAD) have emerged as the mainstay in advanced heart failure patients either as a bridge to transplant (BTT) or destination therapy (DT). Strokes, ischemic from pump thrombosis and hemorrhagic from combination of anti-platelets and anti-coagulants, remain a major cause of morbidity and mortality.
Objective: To identify the prevalence, timing and risk factors of ischemic and hemorrhagic in LVAD patients
Methods: A retrospective analysis of all the LVAD implantations at HH from July 2012 to December 2016 comprising a total of 78 patients with 63 HMII (axial flow) and 15 Heartware (centrifugal flow) implantations to serve as DT in 51 and BTT in 37 patients. Demographics and clinical variables were collected and analyzed. Categorical variables were analyzed using Chi-square test of proportions with statistical significance set at 0.05.
Results: For all patients the median age was 65 years, 82% Caucasian and 16% female. The overall stroke incidence was 27% (n=21, 16 ischemic in 12 patients and 9 hemorrhagic in 9). Age > 65 years had a higher incidence of stroke (36% vs 14%; p <0.05). Mean time from implantation to ischemic and hemorrhagic strokes were 205 and 98 days respectively, with high peri-operative (35 days post implant) risk at 33% for both cohorts. At least two arterial territories were involved in 45% (n=5) and multi-compartmental hemorrhage noted in 66% (n=6). LVADs as DT had a higher incidence of ischemic stroke (24% vs 6% as BTT; P=0.05). Non-Caucasians had a higher incidence of hemorrhagic stroke (55% vs 20% with p = <0.05). The median INR was 1.7 and 2.8 while the median mean arterial pressures was 75 and 84 in the ischemic and hemorrhagic strokes respectively (p <0.05). Age, gender, history of A.fib, HTN, PAD, or aspirin dosage did not predict risk of stroke. Mortality from stroke was 33% (n =4) with ischemic and 66% (n = 6) with hemorrhagic strokes, with a total risk of 47% compared to 17.5% in the non-stroke LVAD population(p = 0.005).
Conclusion: In our study, 1/3 of strokes occurred in the perioperative period with high risk after age 65 years. Non-Caucasians, high mean arterial pressure and high INR were associated with hemorrhagic stroke. Further studies are needed to evaluate modifiable risk factors among LVAD patients.