Relationship of Factor II and Factor X Activity with International Normalized Ratio (INR) in Continuous-Flow Left Ventricular Assist Device (CF-LVAD) Patients: A Cross-Sectional Study

Abstracts S151 between factor activity and INR levels were examined using correlation analyses. Results: 83 CF-LVAD patients (10 females, 10.2%) on chronic warfarin anticoagulation were identified. Mean age of the study population was 59.0±13.3 years and majority had non-ischemic cardiomyopathy (n= 50, 60.2%). Median duration of support at the time of factor testing was 468 days. Mean Factor II activity, Factor X activity, and INR levels were 29.5±11.5 %, 17.6±10.3 %, and 2.2 ± 0.6. Both Factor II (r= -0.739, p < 0.001) and Factor X activity (r= -0.759, p< 0.001) demonstrated a strong negative correlation with INR levels in the whole cohort. However, when CF-LVAD patients within the target therapeutic range (INR 2.0 - INR 2.5) were examined, correlation with INR was modest for Factor II (r= -0.336, p= 0039) and moderate for Factor X (r= -0.568, p< 0.001). Conclusion: Significant variability in factor II and factor X levels were observed in CF-LVAD patients who are within the target INR range. Monitoring factor II and factor X may help predicting unexpected bleeding and thrombotic events in this population.

3( 93) Multi-Institutional Analysis of Temporal Patterns and Nature of Neurological Events after Left Ventricular Assist Device Implant J.M. Stulak ,1 S. Dunlay,1 S. Sharma,1 N. Haglund,2 F.D. Pagani,3 K. Aaronson,3 P. Shah,4 J. Cowger,5 S. Maltais.1  1Cardiovascular Surgery, Mayo Clinic, Rochester, MN; 2Cardiovascular Surgery, Vanderbilt Heart, Nashville, TN; 3Cardiovascular Surgery, University of Michigan, Ann Arbor, MI; 4Cardiovascular Surgery, Inova Fairfax, Falls Church, VA; 5Cardiovascular Surgery, St. Vincent’s Hospital, Indianapolis, IN.

3( 92) Relationship of Factor II and Factor X Activity with International Normalized Ratio (INR) in Continuous-Flow Left Ventricular Assist Device (CF-LVAD) Patients: A Cross-Sectional Study V.K. Topkara ,1 A.B. Eisenberger,1 D. Jennings,1 A.R. Garan,1 M. Yuzefpolskaya,1 K. Takeda,2 H. Takayama,2 V. Ton,1 F. Castagna,1 A.M. Clemons,1 M. Flannery,2 R. Te-Frey,2 A.L. Uryevick,2 M. Maurer,1 D.M. Mancini,1 Y. Naka,2 P.C. Colombo.1  1Medicine, Columbia University, New York, NY; 2Surgery, Columbia University, New York, NY. Purpose: CF-LVAD therapy requires chronic warfarin anticoagulation, which is typically monitored using the International normalized ratio (INR). Growing body of literature suggests that anti-thrombotic effect of warfarin is primarily due to reductions in factor II and factor X activity. We reasoned that assessment of factor II and factor X levels could provide additional information with regards to anticoagulation status of CF-LVAD patients. Methods: CF-LVAD patients at a single academic institution were prospectively studied during routine outpatient follow-up visits. Factor II and factor X activity were determined using clot-based assays. Prothrombin time (PT) and INR levels were concurrently assessed in each patient. Relationship

Purpose: Neurological events continue to represent significant morbidity following left ventricular assist device implant. The temporal nature and patterns of occurrence are not know. We reviewed a large multi center registry to address this gap. Methods: Between May 2004 and May 2015, 1,150 patients (925 male) underwent implantation of a continuous flow LVAD at institutions that comprise the MCS Research Network. Median age at implant was 59 years (range, 18-83). Neurological events were analyzed as early (1 year). Nature of stroke and median post-event survival was analyzed. Results: Median follow-up was 12.4 year (max, 11 years, total 1,757 patientyears of support). Overall survival was 83% at 1 year, 60% at 3 years and 43% at 5 years. There were 192 neurological events during follow-up (0.11/pt-yrs of support); 72 (38%) were ischemic (0.04 PPY), 54 (28%) were hemorrhagic (0.03 PPY), 43 (22%) were transient (0.02 PPY), and 23 (12%) were not specified. Subsequent events occurred in 12 pt (6%) and 4 pt (2%) had a 3rd event. Early neurological events were 72% non-hemorrhagic, intermediate were 75%, and late were 46% non-hemorrhagic (p= 0.03). Conclusion: Early neurological events were significantly more likely to be non-hemorrhagic while late events were hemorrhagic. This has major implications for patient management and counseling of these patients. 3( 94) Utilization and Outcomes of Ventricular Assist Device Support in Adult Congenital Heart Disease: An Analysis of the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) C.J. VanderPluym ,1 P. Eghtesady,2 B.G. Maxwell,3 J.M. Gelow,4 L.J. Burchill,5 S. Maltais,6 R.S. Cantor,7 E.D. Blume.1  1Cardiology, Boston Children’s Hospital, Boston, MA; 2Surgery - Cardiothoracic, Washington University School of Medicine, St. Louis, MO; 3Anesthesiology, Randall Children’s Hospital, Portland, OR; 4Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR; 5Cardiology, Knight