Continuous multi‐day tracking of post‐myocardial infarction recovery of cardiac electrical stability and autonomic tone using electrocardiogram patch monitors

• Published in: Annals of noninvasive electrocardiology Vol. 28; no. 1; pp. e13035 - n/a
• Main Authors: Verrier, Richard L., Varma, Niraj, Nearing, Bruce D.
• Format: Journal Article
• Language: English
• Published: United States John Wiley & Sons, Inc 01.01.2023; Wiley
• Subjects: Analysis; Arrhythmias, Cardiac - diagnosis; Arrhythmias, Cardiac - etiology; Autonomic nervous system; Cardiac arrhythmia; Cardiac patients; Death, Sudden, Cardiac - etiology; Death, Sudden, Cardiac - prevention & control; Defibrillators; EKG; Electrocardiogram; Electrocardiography; Electrocardiography, Ambulatory; Heart; Heart attack; Heart attacks; Heart beat; Heart failure; Heart rate; heart rate variability; Heterogeneity; Humans; Myocardial infarction; Myocardial Infarction - complications; Myocardial Infarction - diagnosis; Myocardial Infarction - therapy; Non-ST Elevated Myocardial Infarction; non‐ST‐elevation myocardial infarction; Patients; Recovery; ST Elevation Myocardial Infarction - diagnosis; ST Elevation Myocardial Infarction - therapy; Stability analysis; State-of-the-art reviews; ST‐elevation myocardial infarction; Syndrome; Task forces; Tracking; T‐wave alternans; T‐wave heterogeneity; Vagus nerve; Valsartan; Variance analysis; United States > US; T-wave heterogeneity; ST-elevation myocardial infarction; T-wave alternans; non-ST-elevation myocardial infarction; heart rate variability
• ISSN: 1082-720X; 1542-474X
• DOI: 10.1111/anec.13035

Background Sudden cardiac death (SCD) risk is elevated following acute myocardial infarction (MI). The time course of SCD susceptibility post‐MI requires further investigation. Methods In this observational cohort study, we employed state‐of‐the‐art noninvasive ECG techniques to track the daily time course of cardiac electrical instability and autonomic function following ST‐segment elevation myocardial infarction (STEMI) and non‐STEMI (NSTEMI). Preventice BodyGuardian MINI‐EL Holters continuously recorded ECGs for 7 days at hospital discharge and at 40 days for STEMI (N = 5) or at 90 days for NSTEMI patients (N = 5). Cardiac electrical instability was assessed by T‐wave alternans (TWA) and T‐wave heterogeneity (TWH); autonomic tone was determined by rMSSD‐heart rate variability (HRV). Results TWA was severely elevated (≥60 μV) in STEMI patients (80 ± 10.3 μV) at discharge and throughout the first recording period but declined by 50% to 40 ± 2.3 μV (p = .03) by Day 40 and remained in the normal range (<47 μV). TWH, a related phenomenon analyzed from 12‐lead ECGs, was reduced by 63% in the five STEMI patients from discharge to normal (<80 μV) at follow‐up (105 ± 27.3 to 39 ± 3.3 μV, p < .04) but increased by 65% in a STEMI case (89 to 147 μV), who received a wearable defibrillator vest and later implantable cardioverter defibrillator. In NSTEMI patients, TWA was borderline abnormal (47 ± 3.3 μV) at discharge and declined by 19% to normal (38 ± 1.2 μV) by Day 90 (p = .05). An overall reciprocal increase in rMSSD‐HRV suggested recovery of vagal tone. Conclusions This study provides proof‐of‐principle for tracking post‐MI SCD risk in individual patients with implications for personalized therapy. Microvolt T‐wave alternans (TWA) in a representative acute ST‐elevation myocardial infarction (STEMI) patient at hospital discharge. QRS‐aligned templates show that TWA was severely abnormal at 79 μV, indicating elevated arrhythmia risk.