Hemodialysis-induced acute myocardial dyssynchronous impairment in children

In adults, recurrent hemodialysis (HD)-induced cardiac injury results in ischemic myocardial dysfunction. Uremic children, like adults, share the full complement of uremia-related cardiovascular abnormalities but without significant atheromatous coronary artery disease. The aim of this study was, to assess the impact of HD on left ventricular (LV) myocardial function in children.

We assessed all single-center chronic HD patients (n = 15, range 1-17 years) excluding those with overt cardiac disease. Regional LV function and mechanical synchronicity was measured echographically by two-dimensional segmental longitudinal, circumferential and radial myocardial strain. All patients were assessed pre-dialysis and at the end of dialysis. In addition, we scanned age-matched controls at rest.

The peak longitudinal strain was lower in uremic patients compared with controls with a significant fall during HD (mean peak strain -19.9 controls, -17.9 pre-HD, -15.3 end of HD, p < 0.05). Radial strain was lower in uremic patients and increased during HD. Circumferential strain was preserved in uremic patients and fell during HD. Intrasegmental deformation synchronicity was progressively worse pre-dialysis and end of dialysis compared with controls. Intradialytic peak longitudinal strain reduction was significantly associated with systolic blood pressure and ultrafiltrate volume (p < 0.05).

Uremic children have impaired regional LV function, with a predisposition to longitudinal axis dysfunction and LV mechanical dyssynchrony, both of which are established markers of ischemic injury. This is further evidence for a characteristic cardiovascular phenotype in uremic patients that predisposes them to subclinical demand ischemia during dialysis.