Purpose: To assess in the peripheral blood alterations of genes related to contractile function, after right ventricular apical pacing in patients with preserved systolic function.
Methods: We divided 30 patients into group A with ventricular pacing post-implant>90%, and group B (controls) with preserved atrioventricular conduction. At the time of implantation and 3 months later, we evaluated in the peripheral blood mRNA concentrations of sarcoplasmic reticulum calcium ATPase (SERCA) and ß-myosin heavy chain (ß-MHC), as well as left ventricular end-diastolic and end-systolic diameter and ejection fraction.
Results: In group A at 3-months follow-up, mRNA levels of SERCA decreased (9,3±1,49 vs 4,04±1,33 p=0,021) and ß-MHC mRNA levels increased (62,12±46,97 vs 424±245 p=0,127). Echocardiographic parameters remained unaltered.In controls all measured parameters showed no significant changes
Conclusions: Permanent right ventricular apical pacing is associated with alterations, in the peripheral blood, in genes regulating ventricular contractile function, while at the same time ventricular function has not yet deteriorated.