Right ventricular dysfunction in ischemic vs nonischemic dilated cardiomyopathy
S Saraiya, A Agrawal, R CAbstract
Background
Non-ischemic cardiomyopathy (NICM) and ischemic cardiomyopathy (ICM) can both lead to right ventricular (RV) dysfunction. Data on direct head to head comparisons of the two entities regarding RV size and function using state-of-the-art imaging techniques is sparse. Such a comparison may help to better understand the underlying pathophysiology of RV dysfunction in both NICM and ICM. Also, differentiation between the two etiologies for cardiomyopathy has important therapeutic implications because ICM may benefit from coronary revascularization.
Purpose
The aim of this study was to investigate RV function using conventional transthoracic and tissue Doppler echocardiography in patients with dilated cardiomyopathy (ICM and NICM groups) and compare the various parameters of the RV assessment in both the groups and correlate with etiology of cardiomyopathy.
Methods
35 patients with NICM and 35 patients with ICM, both groups with LVEF<35% evaluated at our center were included in the study. Transthoracic echocardiography was done for all of them for assessment of Right ventricular volumes and function using conventional and Tissue Doppler parameters.
Results
Baseline LVEF was similar in the two groups with mean LVEF of 28% in ICM group and 27% in NICM group [p=0.71]. RV dysfunction was seen in 22 (62.9%) patients in ICM group as compared to 25 (71.4%) patients in NICM group [p=0.445]. PAH was present in 31(44.3%) patients, with presence of PAH more common in NICM group (n=18, 51.4%) as compared to ICM group (n=13, 37.1%) [p=0.009]. There was a significant positive correlation between LVEF & RV Basal S’ velocity (R2 0.33, p=0.02) and LVEF & TAPSE (R2 0.309, p=0.03) in the ICM group. Presence of more than mild MR (p=0.047), TAPSE < 1.5 cm (p<0.001) and RV Basal S’ velocity < 8.6 cm/s (p=0.02) were significant predictors of RV dysfunction in these patients.
Conclusion
RV dysfunction is common in both NICM and ICM patients. However, there is no significant association of underlying cause of LV dysfunction with presence of RV dysfunction in these patients. Pulmonary artery hypertension was more common in patients in NICM group.