Predictors and clinical impact of pre-existing and acquired thrombocytopenia following transcatheter aortic valve replacement.

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 × 10(3) cell/µL) and moderate-severe (MS) TP (<100 × 10(3) cell/µL). Pre-TAVR point prevalence and post-TAVR incidence of TP were 40% and 79%, respectively (P < 0.001); nadir platelet 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 × 103 cell/µL, ≥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 outcomes. © 2014 Wiley Periodicals, Inc.