Activated Partial Thromboplastin Time-based Clot Waveform Analysis: A Potential for Application in Acute Myocardial Infarction and Its Complications

Background: Activated partial thromboplastin time (aPTT)-based clot waveform analysis (CWA) is a plasma-based global haemostatic assay. Elevated CWA parameters have been associated with hypercoagulability in venous thromboembolism, but its role in arterial thrombotic disease is uncertain. This study aims to explore the relationship between aPTT-based CWA and acute myocardial infarction (AMI) and its complications. Methods: This is a retrospective case-control study that included patients with AMI who underwent emergency cardiac catheterisation and control patients who underwent elective orthopaedic and urological procedures. The pre-procedural aPTT and CWA parameters – min1, min2 and max2 – of AMI patients were compared against those of controls. Results: Compared to controls (N=109), patients with AMI (N=214) had shorter aPTT (26.7±3.3s vs 27.9±1.7s, P<0.001) and higher CWA parameters (min1: 6.11±1.40%/s vs 5.58±1.14%/s; min2: 0.98±0.23%/s2 vs 0.90±0.19%/s2; max2: 0.81±0.20%/s2 vs 0.74±0.16%/s2, all P≤0.001). Elevated CWA parameters, defined as having CWA values above their respective reference ranges, were associated with the occurrence of AMI, with odds ratio (OR) of 2.06 [95% confidence intervals (CI):1.10–3.86], 2.23 (95% CI:1.18–4.24) and 2.01 (95% CI:1.07–3.77) for min1, min2 and max2, respectively. Similarly, elevated min1 and min2 were both individually associated with the presence of adverse outcomes of AMI with ORs of 2.63 (95% CI:1.24–5.59). Conclusions: Patients with AMI had significantly increased CWA parameters. Elevated aPTT-based CWA parameters are significantly associated with the occurrence of AMI and its complications. Potential utility of CWA as risk and prognostic markers for AMI warrants future works.