Hypertension, cardiac state, and the role of volume overload during peritoneal dialysis

The cardiac state and the prevalence of high blood pressure (BP) were analy zed in 21 pediatric patients (mean age 5.3 +/-5.3 years) on chronic periton eal dialysis (CPD), the aim being to specify the impact of hy pervolemia in the etiology of hypertension. C- and N-terminal atrial natriuretic peptide (ANP-C, ANP-N) were measured as possible additional markers of hypervolemi a. Baseline investigations were carried out 0.2 years after initiation of P D, and repeated after 0.9 +/-0.2 years. Fifty-two percent of the patients h ad high BP, and in 40% the nocturnal BP decline was decreased. Left ventric ular hypertrophy was present in 45%, but the systolic and diastolic functio ns of the heart were not impaired. Left ventricular mass correlated signifi cantly with the severity of hypertension and with ANP-N (r=0.79, P <0.01 an d r=0.66. P <0.01, Spearman rank correlation). Significant correlations wer e also found between the severity of hypertension and ANP-N and ANP-C (r=0. 82, P <0.01 and r=0.66, P <0.01, Spearman rank correlation). High BP and ca rdiac impairment were more frequent in the younger and nephrectomized patie nts in whom volume overload seemed to be the most-important etiological fac tor. Our results suggest further that an ANP-N over 3.0 nmol/l combined wit h hypertension is strongly indicative of volume overload in patients on PD.