Comparison of early effects of right ventricular apical pacing on left ventricular functions in single and dual chamber pacemakers

AbstractObjectivesOur study aimed to demonstrate the early negative impact of right ventricular apical pacing induced by single (VVI) and dual chamber (DDD) pacemakers on LV functions in patients with preserved EF. And to assess that single brain natriuretic peptide (BNP) after 2months of implantation is correlated to ventricular dyssynchrony.Methods40 patients with implanted VVI and DDD pacemakers were examined before implantation and again after 2 and 6months of implantation for BNP, left ventricular (LV) systolic and diastolic functions by echocardiography and pulsed tissue Doppler. After 6months, patients with DDD pacemakers were crossed over to VVI mode of pacing for 2weeks with lower rate programed to 60beat per minute then sample for BNP was collected again.ResultsThere was no statistically significant difference in LV systolic and diastolic functions except for myocardial performance index (MPI) with (P value of 0.03). Mean BNP level in VVI pacing was higher than DDD pacing after two months with P value=0.001 while comparison after 6months showed P value=0.023. There was a statistically significant difference between both groups in results of aortic preejection delay (APED) (P value of