A small proportion of patients with STEMI treated via primary PCI experienced late ventricular tachycardia (VT) or ventricular fibrillation (VF), occurring one or more days following the procedure, but late VT or VF with cardiac arrest occurred rarely, especially among patients with uncomplicated STEMI, according to a study published in JAMA Network Open.

Jennifer A. Rymer, MD, MBA, MHS, FACC, et al., included 174,126 patients with STEMI treated with primary PCI between April through December 2020 from the ACC’s Chest Pain – MI Registry. The authors examined the risk of late VT or VF both with or without cardiac arrest. They also investigated the association between late VT or VF and in-hospital mortality among the overall cohort as well as with patients who had uncomplicated STEMI.

Out of all study-eligible patients, 8.9% exhibited VT or VF following primary PCI and 2.4% experienced late VT or VF. In addition, 57.4% of patients had uncomplicated STEMI, with risk of late VT or VF being 1.7% in this cohort. Late VT or VF was associated with increased likelihood of in-hospital mortality in both the overall (adjusted odds ratio [AOR], 6.40; 95% CI, 5.63-7.29) and uncomplicated STEMI cohorts (AOR, 8.74; 95% CI, 6.53-11.70).

Late VT or VF with cardiac arrest was seen in 0.4% of cases in the overall cohort and 0.1% of cases among patients with uncomplicated STEMI. The most significant factor associated with late VT or VF with cardiac arrest was decreasing left ventricular ejection fraction (AOR for every 5-unit decrease ≤40%: 1.67; 95% CI, 1.54-1.85).

“Identifying predictors of late VT or VF is paramount to identifying high-risk patients who should have longer in-hospital monitoring while also facilitating safe, early discharge for low-risk individuals after successful reperfusion,” state the authors. “Our study showed that identifying factors associated with any late VT or VF is challenging, but identifying factors associated with late VT or VF and cardiac arrest can be achieved with higher accuracy.”

Clinical Topics: Arrhythmias and Clinical EP, Implantable Devices, SCD/Ventricular Arrhythmias, Atrial Fibrillation/Supraventricular Arrhythmias

Keywords: National Cardiovascular Data Registries, Chest Pain MI Registry, Arrhythmias, Cardiac, Ventricular Fibrillation