Classical and myocardial deformation echocardiographic indices in chronic kidney disease patients; effects of aging and comparison to healthy controls

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background Patients with chronic kidney disease (CKD) are at high risk for cardiovascular disease compared to the general population. Classic echocardiographic indices of left ventricular (LV) function may not be sensitive enough in detecting early myocardial deterioration in CKD patients while LV speckle tracking (2DSTE) analysis has shown promising results. Dipyridamole stress echocardiography (DIPSE), mostly used to measure coronary flow reserve (CFR), assesses coronary macrovascular and/or microvascular dysfunction in a non-invasive way. Purpose To investigate differences in classic, 2DSTE-related indices, CFR and other DIPSE-induced changes in various echocardiographic parameters between 1) healthy controls and age-matched (younger) CKD patients, 2) younger versus older CKD patients with similar clinical characteristics. Methods We prospectively evaluated 30 healthy controls and 60 consecutive CKD patients 40-75 years old who were followed-up at the CKD outpatient clinic of a University Hospital in Western Greece. A standard echocardiographic analysis including 2DSTE analysis was performed in all subjects before and after dipyridamole infusion. CFR in left anterior descending artery was also assessed. Results The median age of the CKD patients was 63 years and most of them were males (70%). Younger patients with CKD (i.e. <60 years old) had higher E/e" ratio (7.80 ± 2.71 vs 6.06 ± 1.37, p = 0.019), LVMI (114.7 ± 41.1 vs 89.6 ± 21.2, p = 0.017) and relative wall thickness (0.47 ± 0.08 vs 0.40 ± 0.06, p = 0.031) and lower E" (10.6 ± 2.6 vs 2.3 ± 2.9 cm/s, p = 0.045) compared to age and gender-matched healthy controls. Older CKD patients had lower E/A (0.80 ± 0.19 vs 1.03 ± 0.33, p = 0.007) and E" (8.5 ± 1.8 vs 10.6 ± 2.6 cm/s, p = 0.003) compared to younger CKD patients. CFR was higher in healthy controls compared to both younger (3.93 ± 1.25 versus 3.1 ± 0.75, p = 0.009) and older CKD patients (3.93 ± 1.25 versus 2.89 ± 0.88, p < 0.001); no significant difference in CFR was observed between younger and older CKD patients. Dipyridamole-induced changes in other studied echocardiographic indices did not differ significantly among groups. Conclusions In the current study, impaired coronary microcirculation, LV diastolic function and increased LV mass with concentric remodeling were shown to be the principal findings early in the process of CKD. These results may have pathophysiological implications for cardiorenal syndrome type 4 and targeted cardiac assessment in CKD patients. Future studies are needed to assess whether any therapeutic efforts aiming to delay or reverse these changes may have an impact on the cardiovascular prognosis in CKD patients.