Current incidence and predictors of malignant arrhythmias in acute myocardial infarction. Reassessing the role of coronary care units in post-myocardial infarction monitoring
M E Kortman, M van 't Veer, A Galli, M Majidi, T Proudhon, P Porquet, A G Bonomi, L R C Dekker, L C OtterspoorAbstract
Background
Patients with acute myocardial infarction (AMI) are at risk for malignant arrhythmias (MA), defined as sustained ventricular tachycardia (VT) and ventricular fibrillation (VF). Over the past decades, advances in revascularization techniques and medical therapies have led to reduced mortality and improved outcomes following percutaneous coronary intervention. Nevertheless, the standard of care since the early 2000s has been hospital admission with continuous rhythm monitoring for at least 48 hours after an acute myocardial infarction. Taking these modern treatment strategies into account, the current incidence of MA may be lower than previously reported.
Purpose
This systematic review aims to describe the contemporary incidence and predictors of malignant arrhythmia in reperfused AMI patients, with the goal of identifying low-risk individuals who may benefit from shorter monitoring durations, thereby improving patient flow and reducing hospital bed occupancy.
Methods
Studies reporting the incidence of MA in hospitalized AMI patients (2000–2025) were identified through a systematic search, including ST-elevation myocardial infarction (STEMI) and non-ST-elevation myocardial infarction (NSTEMI). Additionally, predictors of MA were identified.
Results
The medians (interquartile range) of study-level reported incidences of MA across studies were 2.8% (2.4–6.4%) in STEMI patients after primary PCI (13 studies), 1.7% (0.7–2.8%) in hospitalized NSTEMI patients (10 studies), and 5.2% (4.0–8.1%) in combined hospitalized STEMI/NSTEMI cohorts (18 studies). All three groups showed considerable heterogeneity (I2≥90%). No temporal decline in MA incidence from 2000 - 2025 could be identified. Most MA (82%) in STEMI patients occurred within 24 hours of admission. Multivariate regression analyses identified Killip class II-IV (4 studies) and peak creatine kinase (3 studies) as independent predictors of MA after reperfusion.
Conclusions
The incidence of malignant arrhythmia in reperfused AMI patients is not negligible, especially within 24 hours. Considerable heterogeneity was demonstrated, likely due to differences in populations and the duration of in-hospital monitoring. Predictors of MA include a worse clinical condition on admission and larger infarct size. Identifying AMI patients with low risk of MA could be proposed to prevent unnecessary hospitalization.Timing onset in-hospital malignant arrhythmiaIncidence of MA after PCI in STEMI patients