LAUSR

PurposeTo determine whether the midrange ejection fraction (mrEF) is associated with increased risk of deterioration of cardiac function (DCF) after dual chamber permanent pacemaker (PPM) implantation.MethodsWe performed a prospective cohort study of relevance in patients with EF ≥ 40% and indications for PPMs. Patient characteristics were recorded at baseline and 1 day, 1 month, 3 months, and 6 months after PPM implantation with leads placed in the right ventricular apex. These included clinical symptoms, signs, biochemical parameters, BNP, echocardiography and ECG parameters, and pacing-related parameter changes. The patients were followed-up for 6 months. Univariate and multivariable Cox regression analyses were performed.ResultsA total of 879 patients were included, aged 35 to 88 years (mean age 67.2 ± 9.6); a total of 81 patients (9.2%) developed DCF after PPM implantation, including LVEF < 40% (57 cases) and increased NYHA class (24 cases). Cox models demonstrated that age ≥ 75 years (HR 2.273 [95% CI, 1.541–3.626]), OMI (HR 2.078 [95% CI, 1.275–3.604]), mrEF (HR 2.762 [95% CI, 1.558–4.769]), moderate mitral regurgitation (HR 2.819 [95% CI, 1.604–4.153]), and right ventricular pacing ≥ 50% (HR 2.311 [95% CI, 1.478–3.937]) were strong predictors for DCF, and NT-proBNP > 1000 ng/L and paced QRS duration ≥ 180 ms were also the independent predictors of DCF.ConclusionsMrEF was associated with increased risk of deterioration of cardiac function after PPM implantation. Moderate mitral regurgitation and increased NT-proBNP levels are also potential independent predictors for deterioration of cardiac function after PPM implantation.