Cardiovascular magnetic resonance imaging pattern in patients with autoimmune rheumatic diseases and ventricular tachycardia with preserved ejection fraction

Abstract

Background: Ventricular tachycardia/fibrillation (VT/VF) may occur in autoimmune rheumatic diseases (ARDs). We hypothesized that cardiovascular magnetic resonance (CMR) can identify arrhythmogenic substrates in ARD patients.

Patients - methods: Using a 1.5 T system, we evaluated 61 consecutive patients with various types of ARDs and normal left ventricular ejection fraction (LVEF) on echocardiography. A comparison of patients with recent VT/VF and those that never experienced VT/VF was performed. CMR parameters included left and right ventricular (LV and RV) end-systolic and end-diastolic volumes (ESV and EDV), T2 signal ratio of myocardium over skeletal muscle, early/late gadolinium enhancement (EGE and LGE), T1/T2-mapping and extracellular volume fraction (ECV).

Results: 21 (34%) patients had a history of recent, electrocardiographically identified, VT/VF. No demographic or functional CMR variables differed significantly between groups. The same was the case for T2 signal ratio and EGE/LGE. Median native T1 mapping values were significantly higher in patients with VT/VF compared to those without [1135.0 (1076.0, 1201.0) vs. 1050.0 (1025.0, 1078.0), p < 0.001], as was the case for mean T2 mapping [60.4 (6.6) vs. 55.0 (7.9), p = 0.009] and median ECV values [32.0 (30.0, 32.0) vs. 29.0 (28.0, 31.5), p = 0.001]. After multivariate corrections for age, LVEDV, LVEF, RVEDV, RVEF, T2 signal ratio, EGE and LGE, these remained significant predictors of having experienced VT/VF in the past.

Conclusions: T1/T2-mapping and ECV offer incremental value as identifiers of arrhythmogenic substrates in ARD patients, beyond traditionally used indices. They can thus guide implantable cardiac defibrillator (ICD) implantation in ARD patients presenting with VT/VF and normal LVEF.

Keywords: Autoimmune rheumatic diseases; Cardiovascular magnetic resonance; Implantable defibrillators; Myocardial fibrosis; Myocardial oedema; Ventricular tachycardia.