Late gadolinium enhancement CMR in patients with tachycardia-induced cardiomyopathy caused by idiopathic ventricular arrhythmias.

BACKGROUND

Idiopathic ventricular arrhythmias in the form of monomorphic premature ventricular contractions (PVC) and/or ventricular tachycardia (VT) can cause tachycardia-induced cardiomyopathy (TICMP). The aim of this study was to determine the prevalence of late gadolinium enhancement (LGE) in patients with TICMP caused by idiopathic ventricular arrhythmias.

METHODS

The study population consisted of 298 consecutive patients (174 F/124 M; mean age 45±17 years) with frequent PVCs and/or VT. TICMP was defined as left ventricular ejection fraction (LVEF) of ≤50% in the absence of any detectable underlying heart disease and improvement of LVEF≥15% after effective treatment of index ventricular arrhythmia.

RESULTS

Twenty-seven (9.1%) patients found to have LVEF≤50% and diagnosed as presumptive TICMP. Improvement in LVEF after effective treatment of index ventricular arrhythmia was observed in 22 of 27 patients (TICMP group; mean PVC burden of 30.8±9.9%). LVEF did not improve in five of 27 patients (primary cardiomyopathy group; mean PVC burden of 28.8±10.1%). LGE-cardiac magnetic resonance (CMR) imaging was performed in 19 of 22 patients with TICMP and one patient (5%) had LGE. All five patients with primary cardiomyopathy underwent LGE-CMR imaging and four patients (80%) had LGE.

CONCLUSIONS

LGE is a rare finding in patients with TICMP caused by idiopathic ventricular arrhythmias. LGE-CMR can be used in the diagnostic work-up of patients with TICMP. Further prospective studies are required to determine the role of LGE-CMR in predicting the recovery of left ventricular systolic dysfunction in patients with presumptive TICMP.