Low calcium dialysate increases cardiac relaxation in CAPD patients.
OBJECTIVE
To establish whether changes in serum calcium affect left ventricular (LV) function in continuous ambulatory peritoneal dialysis (CAPD) patients.


METHODS
This study was conducted on 28 clinically stable CAPD patients (11 females, 17 males). Left ventricular relaxation and systolic function were echocardiographically examined in all patients during standard dialysate (containing 1.75 mmol/L calcium) treatment. All patients were then changed to low calcium dialysate (1.25 mmol/L calcium) for 1 month and all patients were re-examined echocardiographically. Decrement in isovolumic relaxation time (IVRT) and deceleration time (DT), and increment in the ratio of peak early to peak late diastolic velocities (E/Amax) were admitted as indexes showing improvement in LV relaxation. 17 age- and sex-matched controls were also echocardiographically examined.


RESULTS
Deceleration time, interventricular septal thickness at systole (IVSTS) and diastole (IVSTD), and posterior wall thickness at systole (PWS) and diastole (PWD) were higher in CAPD patients using standard dialysate than in normal controls. With the use of low calcium dialysate, DTs were similar but IVSTS, IVSTD, PWS, and PWD values remained higher. In normal controls, E/Amax values were higher than those in CAPD patients using standard dialysate (p < 0.001) and low calcium dialysate (p = 0.009). Serum intact parathyroid hormone level, weight, clinical volume status, and blood pressure were similar throughout the study period. Serum ionized calcium levels were decreased significantly during low calcium dialysate treatment. The changes in IVRT, DT, and E/Amax suggest improvement in LV relaxation during low calcium dialysate treatment.


CONCLUSIONS
Left ventricular relaxation is increased with the use of low calcium dialysate compared with standard dialysate treatment. The idea of possible beneficial effects of increment in LV relaxation on cardiovascular morbidity and mortality deserves further studies.
Tuncer
Murat
M
Division of Nephrology, Department of Medicine, Akdeniz University, Antalya, Turkey. muratep@hotmail.com
Ermiş
Cengiz
C
Süleymanlar
Gültekin
G
Yakupoglu
Gülşen
G
Ersoy
F Fevzi
FF
D000328:Adult; D000368:Aged; D002118:Calcium / Q000097:blood* / Q000494:pharmacology* / Q000627:therapeutic use; D002318:Cardiovascular Diseases / Q000000981:diagnostic imaging / Q000209:etiology / Q000517:prevention & control*; D015314:Dialysis Solutions / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D004452:Echocardiography; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000187:drug effects; D006801:Humans; D007674:Kidney Diseases / Q000097:blood* / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects*; D010531:Peritoneal Dialysis, Continuous Ambulatory; D016277:Ventricular Function, Left / Q000187:drug effects*
D015314:Dialysis Solutions; D002118:Calcium