Ventricular Late Potentials in Patients with Primary and Secondary (Rheumatic) Mitral Valve Prolapse: Relationship with Ventricular Arrhythmias and Mitral Valve Morphology

We enrolled 75 patients with primary mitral valve prolapse (45F, 30M, mean age: 42,1±13) and 30 healthy volunteers marching in regard to sex and age in our study in order to assess the ineidence of ventricular Iate potentials (LP) and the factors associated with them in primary MVP. We also included 30 age - and sex matched patients with secondary (rheumatic) MVP in order to investigate the contribution of the mechanical effects of mitral regurgitation (MR) and mitral valve prolapse in the genesis of LP in patients with primary MVP. Ventricular Iate potential analysis, 24-hours ambulatory ECG monitorization and 2-D echocardiography were performed in every patient. The ineidence of complex ventricular arrhythmias (VA) were found to be higher in patients w ith primary MVP (20%, 15/75) comprared to the secondaı·y MVP (3,3%, 1/30) patients and the control group (0%, 0/30) (p<0.05). Also, the frequency of Iate potentials were higher in the primary MVP group (21,3%, 16/75) compared to the control group (3,3%, 1/30) and secondary MVP group (3.3%, l/30) (p<0.05). In the primary MVP group, age, sex, presence of click and/or MR, anterior leaflet length, mitral annular circumference, DE amplitude and the severity of prolapsing leaflet were found to be not related with ventricular LP. However, in the primary MVP group, in patients with Iate potentials, anterior (0,39±0,07 vs 0,32±0,06 mm) and posterior (0,41±0,05 vs 0,34±0,04 mm) leaflets were found to be thicker, and the posterior leaflet (l ,9±0,3 vs 1 ,72±0,4 cm) was found to be longer than in patients without LP ( <0.05). Al so, the ineidence of complex V A's w ere higher in patients with LP (43,7%, 7/16) than in pts without (13,5%, 8/59) (p<0.05). W e concluded that the ineidence of complex VA and LP were higher in patients with primary MVP than those with secondary (rheumatic) MVP and the control group. Although the Iate potentials detected in patients with primary MVP were found to be related to with the thickness of both leaflets and complex VA, they were not related to the mechanical effects of mitral prolapse and MR. Further studies are needed to detect factors associated ·with LP and the elinical value of LP in patients with primary MVP.