Evaluation of right ventricular function with 3D echo in patient with pacing induced cardiomyopathy
█ Original article
Kádár Rebeka, Jenei Csaba, Clemens Marcell, Csanádi Zoltán
Debreceni Egyetem Klinikai Központ, Kardiológiai és Szívsebészeti Klinika, Kardiológiai Klinika, Debrecen
Background: Right ventricular pacing may worsen left ventricular systolic function causing heart failure, but the exact mechanism of the left ventricular dysfunction is unknown. The purpose of this study was to examine the right ventricular function by three-dimensional echocardiography in patients with left ventricular dysfunction accompanied by long-term right ventricular pacing.
Methods: We analysed consecutive patients receiving permanent pacemaker due to atrioventricular block from 2015 January to 2017 March (n=335). During the mean follow-up period (33±8 months) four patients were selected with at least 5% decrease in the left ventricular ejection fraction measured by two-dimensional echocardiography (B group). Four age and sex-matched patients with similar comorbidities but showing no significant left ventricular dysfunction served as controls (K) from the same time interval. Right ventricular function was assessed by 3D echocardiography.
Results: In both groups there were 3 men, and the mean age was similar (B: 68±6 y vs. K: 66±10 y; p=0.65). Right ventricular ejection fraction was significantly higher in controls compared to patients (K: 49±7.8% vs. B: 36±3.1%; p=0.02), while the right ventricular volumes [end-systolic (K: 79±47 ml vs. B: 71±7 ml; p=0.77), end-diastolic (K: 151±73 ml vs. B: 111±11 ml; p=0.36)] did not differ significantly. We did not find any important differences between the groups regarding the permanent right ventricular pacing rate (K: 93±6% vs. B: 84±20%; p=0.5), systolic pulmonary pressure (K: 34±6 mmHg vs. B: 35±18 mmHg; p=0.92), or the severity of tricuspid regurgitation.
Conclusion: Left ventricular dysfunction caused by permanent right ventricular pacing results in right ventricular systolic dysfunction. The decrease of right ventricular ejection fraction is not associated with right ventricular enlargement or increase of pulmonary pressure.