# Subclinical myocardial changes in idiopathic premature ventricular contractions: insights from cardiac magnetic resonance imaging

## TL;DR

This study finds that nearly half of patients with idiopathic PVCs show hidden heart changes via MRI, even when other tests appear normal.

## Contribution

The study reveals subclinical myocardial changes in idiopathic PVCs using CMRI, suggesting hidden pathology not detected by standard tests.

## Key findings

- 52% of patients with idiopathic PVCs showed subclinical myocardial changes via CMRI.
- 33% of patients had late gadolinium enhancement, and others had elevated native T1 or ECV values.
- Patients with myocardial changes had higher rates of non-sustained ventricular tachycardia and more PVCs.

## Abstract

Idiopathic premature ventricular contractions (PVCs) are defined as PVCs in the absence of obvious structural heart disease, which is typically excluded by electrocardiography (ECG), echocardiography. The purpose of this study was to investigate the prevalence of subclinical myocardial changes detected by cardiac magnetic resonance imaging (CMRI) in patients with idiopathic PVCs.

In this cross-sectional study, thirty-three patients (age 54 ± 17 years, 19 male) with idiopathic PVCs diagnosed using ECG and echocardiography who subsequently underwent CMRI at 3-Tesra between September 2019 and May 2024 were included in this study. CMRI, including late gadolinium enhancement (LGE), native T1 values, and extracellular volume fraction (ECV), was performed.

PVCs most frequently originated from the right ventricular outflow tract (15 of 33 patients, 45%). CMR identified myocardial changes in 17/33 (52%). LGE was present in 11/33 (33%). Importantly, mapping-derived indices (native T1 values/ECV) revealed subclinical interstitial changes in several patients, including those without LGE (four with elevated native T1 and two with elevated ECV). Among patients with myocardial changes, the incidence of non-sustained ventricular tachycardia and the maximum consecutive number of PVCs were significantly higher than in those without myocardial changes (P < 0.05 for both).

In this exploratory study, multiparametric CMRI frequently revealed subclinical myocardial changes in patients with idiopathic PVCs despite normal ECG and echocardiography. Given the small sample size and the heterogeneous, ECG-based estimation of PVC origin, these findings should be considered hypothesis-generating, and larger studies are warranted.

Infographic summarizing a study on subclinical myocardial changes in idiopathic PVCs using cardiac MRI, showing a population of 33 patients, MRI protocols for detecting myocardial changes, and a key finding that 52% had changes on CMRI, detailed in an overlapping Venn diagram with the main characteristics listed.