Right atrial size and deformation in patients with dilated cardiomyopathy undergoing cardiac resynchronization therapy

Abstract

To evaluate right atrial (RA) morphology and deformation in patients with dilated cardiomyopathy (DCM). A total of 130 patients with either idiopathic (n = 70) or ischaemic (n = 60) DCM, and 60 controls underwent clinical examination, standard echocardiography, and RA two-dimensional strain echocardiography (2DSE). Six months after implantation of a cardiac resynchronization therapy (CRT) device, the DCM patients were re-evaluated, if their left ventricular (LV) end-systolic volume had decreased by at least 15% they were defined as echocardiographic responders. All DCM patients were in NYHA class III before CRT, with a mean LV ejection fraction of 29.2 +/- 5.5%. After CRT, 94 patients were in NYHA functional class I-II. The patients were subdivided into echocardiographic responders (n = 85) and non-responders (n = 45). Both RA area index (19.7 +/- 5.5 cm(2)/m in non-responders vs. 13.2 +/- 4.4 cm(2)/m in responders; P < 0.001) and RA strain of lateral wall (24.3 +/- 10.2% in non-responders vs. 40.2 +/- 8.9% in responders; P < 0.001) were significantly different between the two groups. A RA area index >or=16 cm(2)/m showed a sensitivity and specificity of 87.1 and 95.4%, respectively (P < 0.0001) to predict a negative response to CRT. By multivariable analysis, increased RA area index (P < 0.001), ischaemic aetiology of DCM (P < 0.01), and less severe radial intraventricular dyssynchrony were independent determinants of an unfavourable response to CRT. Right atrial area index was increased and RA myocardial deformation was impaired in patients with DCM who were non-responders to CRT.