Ventricular Arrhythmias in Myocarditis: Characterization and Relationships With Myocardial Inflammation

Giovanni Peretto; Simone Sala; Stefania Rizzo; Anna Palmisano; Antonio Esposito; Francesco De Cobelli; Corrado Campochiaro; Giacomo De Luca; Luca Foppoli; Lorenzo Dagna; Gaetano Thiene; Cristina Basso; Paolo Della Bella

doi:10.1016/j.jacc.2020.01.036

Ventricular Arrhythmias in Myocarditis: Characterization and Relationships With Myocardial Inflammation

J Am Coll Cardiol. 2020 Mar 10;75(9):1046-1057. doi: 10.1016/j.jacc.2020.01.036.

Authors

Affiliations

¹ Department of Cardiac Electrophysiology and Arrhythmology, IRCCS San Raffaele Hospital and Vita-Salute University, Milan, Italy. Electronic address: peretto.giovanni@hsr.it.
² Department of Cardiac Electrophysiology and Arrhythmology, IRCCS San Raffaele Hospital and Vita-Salute University, Milan, Italy.
³ Department of Cardiovascular Pathology, Padua Hospital and University, Padua, Italy.
⁴ Department of Cardiovascular Radiology and Cardiac Magnetic Resonance Unit, IRCCS San Raffaele Hospital and Vita-Salute University, Milan, Italy.
⁵ Unit of Immunology, Rheumatology, Allergy and Rare Diseases (UnIRAR), IRCCS San Raffaele Hospital and Vita-Salute University, Milan, Italy.
⁶ IRCCS San Raffaele Hospital and Vita-Salute University, Milan, Italy.

PMID: 32138965
DOI: 10.1016/j.jacc.2020.01.036

Abstract

Background: Ventricular arrhythmias (VAs) have never been systematically investigated in patients with myocarditis at different stages.

Objectives: The purpose of this study was to compare baseline and follow-up characteristics of VAs in patients with active myocarditis (AM) versus previous myocarditis (PM).

Methods: A total of 185 consecutive patients (69% males, age 44 ± 15 years, left ventricular ejection fraction 49 ± 14%) with myocarditis and VA at index hospitalization, including ventricular fibrillation, ventricular tachycardia (VT), nonsustained ventricular tachycardia (NSVT), and Lown's grade ≥2 premature ventricular complexes, were enrolled. AM and PM groups were defined based on endomyocardial biopsy and cardiac magnetic resonance findings. A subset of patients (n = 46, 25%) also underwent electroanatomic mapping and VA transcatheter ablation.

Results: At presentation, AM patients (n = 123, 66%) more commonly had ventricular fibrillation (8 cases vs. 0 cases; p = 0.053), and both irregular (61% vs. 11%; p < 0.001) and polymorphic VA (NSVT and VT: 19% vs. 2%; p = 0.002; premature ventricular complexes: 63% vs. 16%; p < 0.001). Only in PM patients with NSVT or VT, the dominant morphology (right-bundle branch block with superior axis) was 100% predictive of abnormal LV inferoposterior substrate at both cardiac magnetic resonance and electroanatomic mapping. At 27 ± 7 months prospective follow-up, 55 patients (30%) experienced malignant VA (AM vs. PM, p = 0.385). Although a prevalence of polymorphic and irregular VA was confirmed in AM patients with persistent inflammation in follow-up (58%), a predominance of monomorphic and regular VA was found in AM patients after myocarditis healing (42%), as well as in PM patients (all p < 0.001).

Conclusions: In myocarditis patients, polymorphic and irregular VA are more common during the active inflammatory phase, whereas monomorphic and regular VA are associated with healed myocarditis.

Keywords: cardiac magnetic resonance; electroanatomic mapping; endomyocardial biopsy; myocarditis; ventricular arrhythmias.

MeSH terms

Adult
Arrhythmias, Cardiac / epidemiology*
Arrhythmias, Cardiac / etiology*
Arrhythmias, Cardiac / therapy
Female
Humans
Italy / epidemiology
Male
Middle Aged
Myocarditis / complications*
Myocarditis / epidemiology
Prospective Studies