Cited 39 times since 2015 (4.3 per year) source: EuropePMC Heart rhythm, Volume 12, Issue 10, 22 4 2015, Pages 2106-2114 Myocardial scar predicts monomorphic ventricular tachycardia but not polymorphic ventricular tachycardia or ventricular fibrillation in nonischemic dilated cardiomyopathy. Piers SR, Everaerts K, van der Geest RJ, Hazebroek MR, Siebelink HM, Pison LA, Schalij MJ, Bekkers SC, Heymans S, Zeppenfeld K
Background
The relation between myocardial scar and different types of ventricular arrhythmias in patients with nonischemic dilated cardiomyopathy (NIDCM) is unknown.
Objectives
The purpose of this study was to analyze the effect of myocardial scar, assessed by late gadolinium enhancement cardiac magnetic resonance imaging (LGE-CMR), on the occurrence and type of ventricular arrhythmia in patients with NIDCM.
Methods
Consecutive patients with NIDCM who underwent LGE-CMR and implantable cardioverter-defibrillator (ICD) implantation at either of 2 centers were included. LGE was defined by signal intensity ≥35% of maximal signal intensity, subdivided into core and border zones (≥50% and 35%-50% of maximal signal intensity, respectively), and categorized according to location (basal or nonbasal) and transmurality. ICD recordings and electrocardiograms were reviewed to determine the occurrence and type of ventricular arrhythmia during follow-up.
Results
Of 87 patients (age 56 ± 13 y, 62% male, left ventricular ejection fraction 29% ± 12%), 55 (63%) had LGE (median 6.3 g, interquartile range 0.0-13.8 g). During a median follow-up of 45 months, monomorphic ventricular tachycardia (VT) occurred in 18 patients (21%) and polymorphic VT/ventricular fibrillation (VF) in 10 (11%). LGE predicted monomorphic VT (log-rank, P < .001), but not polymorphic VT/VF (log-rank, P = .40). The optimal cutoff value for the extent of LGE to predict monomorphic VT was 7.2 g (area under curve 0.84). Features associated with monomorphic VT were core extent, basal location, and area with 51%-75% LGE transmurality.
Conclusions
Myocardial scar assessed by LGE-CMR predicts monomorphic VT, but not polymorphic VT/VF, in NIDCM. The risk for monomorphic VT is particularly high when LGE shows a basal transmural distribution and a mass ≥7.2 g. Importantly, patients without LGE on CMR remain at risk for potentially fatal polymorphic VT/VF.
