Objective: To explore the relationship between heart failure and changes in intracellular calcium concentration of the myocardium.
Methods: The intra-and extracellular concentration of ionized calcium and total calcium of myocardium in 11 cases of heart failure was measured using calcium fluorescence indicator Fura-2 and atom absorption spectrophotometry. The activity of the erythrocyte membrane pump was determined with hemolysate chemical method.
Results: The concentration of ionized calcium in myocardial cells and the erythrocyte was significantly higher in the patients with heart failure (280.85 +/- 47.8 nmol/L, 1.76 +/- 0.04 F335/F385) than in those without heart failure (121.88 +/- 13.15 nmol/L, 1.47 +/- 0.08 F335/F385). Total calcium in the erythrocyte was also increased markedly in the patients with heart failure, but the activity of the erythrocyte membrane pump was lower than in those without heart failure. The intracellular calcium of the peripheral erythrocyte and the activity of membrane pump returned to normal after the heart failure was cured.
Conclusion: There is excessive calcium accumulation in the myocardium and erythrocyte and the latter may be cause of the disturbance of myocardial diastolic function during heart failure.