T-wave inversion on ECG predicts ventricular arrhythmia events in mitral valve prolapse

Abstract Background In mitral valve prolapse (MVP), the presence of T-wave inversion (TWI) on ECG recordings and its relation with ventricular arrhythmias (VA) and VA events (VAE) has never been prospectively assessed in a large serie of patients. Purpose To study the TWI prevalence in MVP and its link with outcome. Methods In a bicentric prospective study, we performed comprehensive echocardiography and ECG analyses. TWI was defined as T-wave inversion in ≥ 2 of the inferior leads. A subgroup of patients underwent cardiac magnetic resonance (CMR). Outcome included cardiovascular events (CVE) and ventricular arrhythmia events (VAE). Results Out of 1177 patients (629 men, 53%; 52±16 years) with MVP, 104 (9%) had TWI. Myxomatous degeneration (MD, n=739, 63%), and mitral annulus disjunction (MAD, n=419, 36%) were common. TWI prevalence increased with regurgitation grade, with more pronounced mitral valve dystrophy including MAD and MD, and worse cardiac remodeling (all p<0.0001). At baseline, VA were more common in patients with TWI, and even more in those displaying both TWI and late gadolinium enhancement (LGE+). TWI was associated with a decreased survival without CVE (P=0.004), and a decreased survival without VAE (p<0.0001), with a gradation according to the number of inferior leads with T-wave inversion. In multivariable analysis TWI was an independant predictor of VAE (HR: 2.3 [1.1-5.0], p=0.028) as was age (p=0.025), LVESD (p<0.0001), MAD (p=0.009), and MD (p=0.008). In the subset of patients with CMR performed (n=511, 43%), TWI (HR: 2.7 [1.2-5.9], p=0.014) remained an independant predictor of VAE, in conjunction with MAD (p=0.015), and LGE+ (p=0.047). Conclusion In this prospective study, TWI (9% of patients) was associated with the etiology of MVP, MR severity, worse LV remodelling, and with history of VA at baseline. TWI predicted ventricular arrhythmia events, with an additive predictive value over LGE+. TWI should be regarded as a meaningful parameter in the arrhythmogenic assessment of MVP as it could reflect an abnormal cell membrane potential able to trigger VA.