In adults recurrent haemodialysis (HD) induced cardiac injury results in sequential myocardial damage with an attendant increased mortality. Uraemic children, like adults, share the full gamut of uraemia related cardiovascular abnormalities but without significant classical atheromatous coronary artery disease (CAD). The aim of this study was to determine the effects of uraemia and HD on segmental LV function in children.
Method: We assessed all single-centre chronic HD patients (n=15, range 1-17 years) on 4hrs, 3 times/wk treatments, excluding those with overt cardiac disease. Regional LV function was measured echographically by two-dimensional peak segmental longitudinal, circumferential and radial strain and synchronicity of systolic deformation between segments. All patients underwent pre-dialysis assessments and during peak stress at the end of dialysis. For comparision we also scanned age matched controls at rest.
Results: The peak longitudinal strain was significantly lower in dialysis patients compared with controls,dropping further on HD (mean segmental longitudinal strain -19.9 [controls], -17.9 [pre-dialysis], -15.3 [end of dialysis], p<0.05). No significant difference in baseline and intradialytic circumferential strain or radial strain was observed. Intrasegmental systolic deformation synchronization fell in dialysis patients compared with controls and at the end of dialysis combared with pre-dialysis.
Conclusion: Uraemic children have impaired regional LV function, with an acute deterioration during HD. This data,combined with previous adult studies of reduced myocardial blood flow and raised biochemical markers of myocardial injury raises the possibility that the characteristic cardiovascular phenotype in HD patients predisposes to significant demand ischaemia, even in the absence of epicardial CAD.