Abstract 12858: Lower Body Surface Area is Highly Related to Mortality due to Stroke or Systemic Bleeding in Patients Receiving an Axial Flow Blood Pump as Left Ventricular Assist Device
Background Even though left ventricular assist devices (LVAD) may fit into the body of small adult patients, their prognosis is worse than that of larger patients. We investigated the relationship between cause of death and body surface area (BSA) in patients who received LVAD.
Methods One hundred and sixty-seven patients who received BerlinHeart INCOR LVAD in our center without use of another VAD before or just after its implantation were studied. Median BSA was 2.00 m² (range: 1.56 - 2.47 m²). We calculated p-value of the log-rank test for Kaplan-Meier probability of freedom from events during VAD support in two groups (larger BSA and smaller BSA) divided by a cut-off point of BSA corresponding to each patient. From the line graph showing the relationship between BSA for the cut-off point and the p-value, the definitive cut-off point was determined on the basis that with a decrease in the BSA below this value, the p-value gradually increases. The events considered for freedom from events were: 1. death due to stroke or systemic bleeding, 2. death due to sepsis, 3. death or urgency listing for heart transplantation due to difficulties of coagulation management (i.e., embolic events or bleeding), 4. death due to sepsis or urgency listing due to device infection.
Results For freedom from death due to stroke or systemic bleeding, a definitive cut-off point existed and this was BSA of 1.867 m². For freedom from death or urgency listing due to difficulties of coagulation management, the definitive cut-off point was also BSA of 1.867 m². For freedom from death due to sepsis and for freedom from urgency listing due to device infection or death due to sepsis, no definite cut-off point was found. Multivariate Cox analysis revealed that BSA<1.867 m² was an independent risk factor for death due to stroke or systemic bleeding (hazard ratio: 2.665, 95% confidence interval: 1.349-5.265, p=0.0048). One-year freedom from death due to stroke or systemic bleeding during VAD support was 49.1% in patients with BSA<1.867 m² (n=42) and 82.7% in those with BSA≥1.867 m² (n=125) (p=0.0033).
Conclusions Considering the high mortality rate due to stroke or systemic bleeding, development of a special device for patients with BSA<1.867 m² appears necessary.
- © 2011 by American Heart Association, Inc.