Association between baseline platelet count and severe adverse outcomes following percutaneous coronary intervention

Ischemic and Bleeding Events Associated with Thrombocytopenia and Thrombocytosis after Percutaneous Coronary Intervention in Patients with Acute Myocardial Infarction

The early and late ischemic and bleeding clinical outcomes according to baseline platelet count after percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) remain unclear. Overall, 10,667 patients from the Cardiovascular Risk and identification of potential high-risk population in AMI (COREA-AMI) I and II registries were classified according to the following universal criteria on baseline platelet counts: (1) moderate to severe thrombocytopenia (platelet < 100 K/μL, n = 101), (2) mild thrombocytopenia (platelet = 100~149 K/μL, n = 631), (3) normal reference (platelet = 150~450 K/μL, n = 9832), and (4) thrombocytosis (platelet > 450 K/μL, n = 103). The primary endpoint was the occurrence of major adverse cardiovascular events (MACE). The secondary outcome was Bleeding Academic Research Consortium (BARC) 2, 3, and 5 bleeding. After adjusting for confounders, the moderate to severe thrombocytopenia (HR, 2.03; 95% CI, 1.49-2.78); p < 0.001), mild thrombocytopenia (HR, 1.15; 95% CI, 1.01-1.34; p = 0.045), and thrombocytosis groups (HR, 1.47; 95% CI, 1.07-2.03; p = 0.019) showed higher 5-year MACE rates than the normal reference. In BARC 2, 3, and 5 bleeding outcomes, the bleedings rates were higher than the normal range in the moderate to severe thrombocytopenia (HR, 2.18; 95% CI, 1.36-3.49; p = 0.001) and mild thrombocytopenia (HR, 1.41; 95% CI, 1.12-1.78; p = 0.004) groups. Patients with AMI had higher 5-year MACE rates after PCI if they had lower- or higher-than-normal platelet counts. Thrombocytopenia revealed higher early and late bleeding rates whereas thrombocytosis showed long-term bleeding trends, although these trends were not statistically significant.

Blood Platelet Count at Hospital Admission Impacts Long-Term Mortality in Patients with Acute Coronary Syndrome

INTRODUCTION

Platelets play a fundamental role in the pathogenesis of acute coronary syndrome (ACS). The platelet count (PC) at hospital admission is easy to obtain, but whether thrombocytopenia or/and thrombocytosis impact long-term mortality (LTM) after ACS is unclear.

OBJECTIVE

To evaluate the effect of PC at hospital admission on LTM in patients with ACS.

METHODS

This retrospective cohort study included patients with the ICD-10 codes for unstable angina (I.20) and acute myocardial infarction (I.21, I.22). Thrombocytopenia was defined as a blood PC <150 G/L and thrombocytosis as a PC >450 G/L. Additional platelet indices which were tested included plateletcrit (PCT), the mean platelet volume (MPV), the platelet distribution width (PDW), and the platelet larger cell ratio (P-LCR). Data on all-cause death were obtained from the National Health Fund database.

RESULTS

The study included 3,162 patients with a median follow-up of 27.2 months (interquartile range 12.5-46.8 months; max 68.7 months). Patients with thrombocytopenia and thrombocytosis yielded a higher maximal analyzed 5-year mortality rate in comparison with normal PC patients (45.8 and 47.7 vs. 24.2%, respectively; p < 0.00001) which was mainly driven by higher deaths at 1-2 years after ACS. The 5-year LTM was also significantly higher in patients with abnormal PCT and MPV levels in comparison with patients with PCT and MPV within the normal range. Other platelet indices (PDW, P-LCR) were not associated with a worse outcome. The Cox proportional hazards model revealed that thrombocytopenia at admission was independently associated with higher LTM after ACS (RR 1.83; 95% CI 1.1-3.0; p = 0.01).

CONCLUSIONS

Both thrombocytopenia and thrombocytosis at hospital admission in post-ACS patients are associated with a significant almost two times higher 5-year mortality rate.