FREQUENCY OF EARLY STENT THROMBOSIS (ACUTE AND SUBACUTE) IN PATIENTS PRESENTING WITH ACUTE ST ELEVATION MYOCARDIAL INFARCTION (STEMI) UNDERGOING PRIMARY PERCUTANEOUS CORONARY INTERVENTION (PCI)

Abstract

Sudden cardiac stent thrombosis (ST) is a severe clinical risk that can lead to high fatality rates. However, data are scarce on the prevalence of early ST events following ‘primary percutaneous coronary intervention’ (pPCI) and the characteristics that predict it, particularly among Pakistani patients. Objective: The objective is to determine possible indicators and evaluate ‘the frequency of acute and sub-acute stent thrombosis’ (ST) after ‘primary percutaneous coronary intervention’ (PCI). Methods: Five hundred individuals who had undergone primary PCI were enrolled from July 2022 to December 2023. Telephone follow-up assessments were used to gather information on 30-day results, including death rates, recurrence of symptoms, and episodes of ST. ‘ST was classified as acute’ (occurring ‘during the procedure’) or ‘sub-acute’ (‘occurring within 30 days post-procedure) using standardised criteria established by the ‘Academic Research Consortium. Results:  In this study, 500 patients were enrolled, primarily male (80.4%, 362 patients). ‘Stent thrombosis’ (either acute or sub-acute) was observed in 6.8% of patients, with 10.1% (4) classified as definite ST and the remaining 91.9% (34) as probable ST. Male patients were more prevalent among those who developed ST, along with a higher incidence of hypertension, diabetes, reduced left ventricular ejection fraction (LVEF) pre-PCI, and higher Killip Class. Patients with ST experienced a higher in-hospital mortality rate compared to those without ST, with a p-value of 0.02. Notably, ‘Killip Class’ (‘III-IV’) emerged as ‘an independent ST predictor in this patient cohort. These findings underscore the importance of risk assessment and vigilant management, particularly in patients presenting with higher Killip Class and other associated risk factors, to mitigate ST occurrence and adverse outcomes following primary PCI. Conclusion: Early stent thrombosis (ST) appears relatively common in patients undergoing primary PCI. Those with diabetes and hypertension face an elevated risk of ST, while patients presenting in ‘Killip Class III-IV’ demonstrate an ‘independent predictive’ factor for early ST.