Original Studies Predictors and Clinical Impact of Pre-existing and Acquired Thrombocytopenia Following Transcatheter Aortic Valve Replacement Michael P. Flaherty, 1 * MD, PhD, Amr Mohsen, 1 MD, Joseph B. Moore, 1 IV , PhD, Carlo R. Bartoli, 2 MD, PhD, Erik Schneibel, 1 MD, Wasiq Rawasia, 1 MD, Matthew L. Williams, 3 MD, Kendra J. Grubb, 3 MD, and Glenn A. Hirsch, 1 MD, MHS Background: Data are limited regarding transcatheter aortic valve replacement (TAVR)- related thrombocytopenia (TP). We sought to thoroughly characterize the presence, clinical impact, and severity of TP associated with TAVR. Methods and Results: Data were collected from 90 patients who underwent TAVR using the Edwards SAPIEN valve (59 TF, 29 TA, 2 Tao). Platelet counts were evaluated peri-procedurally and for 8 days following TAVR. Platelet levels were compared and patients were divided into a no TP (No-TP) group 1, acquired (new) TP (NTP) group 2, pre-existing (pre-TAVR) TP (PTP) group 3, and further stratified based on the severity of TP: mild (M) TP (100–149 3 10 3 cell/mL) and moderate–severe (MS) TP (<100 3 10 3 cell/mL). Pre-TAVR point prevalence and post-TAVR incidence of TP were 40% and 79%, respectively (P < 0.001); nadir plate- let count in all groups occurred day 4 post-TAVR. Baseline predictors for developing MS TP in groups 2–3 included baseline TP, leaner body mass, smaller pre-procedural aortic valve area, higher peak aortic jet velocity, and worsening baseline renal function. Development of “major” TP (nadir platelet count <100 3 103 cell/mL, 50% decrease) predicted a higher risk of major vascular complications (OR 2.78 [95% CI, 1.58–3.82]) and major bleeding (OR 3.18 [95% CI, 1.33–5.42]) in group 3. Conclusion: TAVR-related TP is predictable and classification by PTP and TP severity prior to TAVR allows for better risk stratification in predicting in-hospital clinical outcomes. Major TP in the presence of worsening TP is predictable and is associated with worse clinical out- comes. V C 2014 Wiley Periodicals, Inc. Key words: TAVR; thrombocytopenia; predictors 1 Division of Cardiovascular Medicine, University of Louisville School of Medicine and Jewish Hospital Rudd Heart and Lung Institute, Louisville, Kentucky 2 Division of Cardiovascular Surgery, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 3 Department of Cardiac and Thoracic Surgery, University of Louisville School of Medicine and Jewish Hospital Rudd Heart and Lung Institute, Louisville, KY. Additional Supporting Information may be found in the online ver- sion of this article. Conflict of interest: None of the authors have any conflicts of inter- est. Michael P. Flaherty, and Amr Mohsen contributed equally to this work *Correspondence to: Michael P. Flaherty, M.D., Ph.D., Assistant Professor of Medicine, Physiology & Biophysics, Division of Cardi- ovascular Medicine, University of Louisville School of Medicine, Rudd Heart and Lung Center, 201 Abraham FlexnerWay, Suite 800, Louisville, KY 40202. E-mail: mpflah01@louisville.edu Received 26 February 2014; Revision accepted 6 September 2014 DOI: 10.1002/ccd.25668 Published online 00 Month 2014 in Wiley Online Library (wileyonlinelibrary.com) V C 2014 Wiley Periodicals, Inc. Catheterization and Cardiovascular Interventions 00:00–00 (2014)