Coronary microcirculation and left ventricular diastolic function but not myocardial deformation indices are impaired early in patients with chronic kidney disease

AIM

To investigate abnormalities in myocardial strain and classic echocardiographic indices and coronary flow reserve (CFR), in younger versus older CKD patients.

METHODS

Sixty consecutive CKD patients (<60 years old n = 30, ≥60 years old n = 30) and 30 healthy controls (age- and gender-matched with younger CKD patients) were recruited. An echocardiographic assessment including myocardial strain indices (i.e. global longitudinal strain -GLS -, TWIST, UNTWIST rate) was performed at baseline and following dipyridamole administration in all participants.

RESULTS

Younger CKD patients had higher E/e', left ventricular mass index and relative wall thickness and lower E' (p < .005 for all) compared to healthy controls. Older CKD patients had lower E/A and E' (p < .05 for both) compared to younger CKD patients; these differences did not remain significant after adjustment for age. CFR was higher in healthy controls compared to younger and older CKD patients (p < .05 for both) without a significant difference between CKD groups. There were no significant differences in GLS, TWIST or UNTWIST values among the three groups of patients. Dipyridamole-induced changes did not differ significantly among the three groups.

CONCLUSIONS

Compared to healthy controls, impaired coronary microcirculation and left ventricular diastolic function, but not myocardial strain abnormalities, are found in young CKD patients and deteriorate with aging.

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

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. &lt;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 &lt; 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.

The prognostic role of myocardial strain indices and dipyridamole stress test in renal transplantation patients

INTRODUCTION

Renal transplantation (RT) increases survival in end-stage kidney disease patients but cardiovascular diseases remain the leading cause of morbidity and mortality. We evaluated the role of myocardial strain (2DSTE) indices and dipyridamole-induced (DIPSE) changes in echocardiographic parameters at baseline for the prediction of clinical events and echocardiographically assessed deterioration of cardiac function in a RT population.

METHODS

Forty-five RT patients underwent an echocardiographic study at baseline including 2DSTE and DIPSE. If no cardiovascular/renal event occurred, patients were investigated at 3-year follow-up; eight patients presented a clinical event while 37 patients were re-evaluated.

RESULTS

Coronary flow reserve (CFR) was abnormal in 24% of the population. DIPSE induced improvements in classic and 2DSTE systolic and diastolic echocardiographic indices including TWIST, UNTWIST, global longitudinal strain (GLS), and circumferential strain (P < .05 for all). Compared to baseline, deteriorations in E/E', LVEF, E', and TWIST were observed at follow-up (P < .05 for all). DIPSE-induced changes in GLS, global radial strain, and LVEF were associated with changes in these indices at follow-up (P < .05 for all). Higher LV mass index, E/E', and lower MAPSE, E', and CFR at baseline were associated with the occurrence of clinical events at follow-up (P < .05 for all).

CONCLUSIONS

In RT patients, coronary vascular dysfunction (ie, low CFR) was associated with the occurrence of adverse events. DIPSE-induced changes in myocardial strain and classic echocardiographic indices could identify individuals with a subclinical deterioration in cardiac function at follow-up. This may indicate that DIPSE could serve as a means to assess myocardial reserve in this population.