4.Synergistic Effect of Magnesium and Diltiazem on Reversal of Myocardial Cell Membrane Stress and Dyskinesia

摘要

Administration of the calcium antagonist, diltiazem, abrogates the exercise stress test-induced occurrence of the silent ST segment depression in many patients without symptoms of coronary artery disease, suggesting that myocardial dyskinesia plays an important role in this phenomenon. In order to avoid daily diltiazem dosages higher than 270mg, the possibility of co-treatment with magnesium, was investigated. Analysis of the effect of có-treatment of diltiazem-magnesium in the reversal of ST segment depression during treadmill electrocardiography exercise testing was undertaken in 10 patients, who did not exhibit clinical symptoms of coronary artery disease, but still presented ST segment depression during exercise stress testing. Seven of these patients were males, between 22 and 63 years old, (mean age was 42.1 years]. These patients were already receiving atenolol 25mg (MID) and diltiazem 90mg (TID). Following baseline testing, magnesium (150 mg BID) was also initiated and the treadmill electrocardiography exercise testing was repeated under the standard Bruce protocol five to six days later. The magnesium therapy corrected the STj and STy deviations without significant alteration in the heart rate in the control (157.1± 23.2 bpm) versus the treatment (131.1 ± 11.2 bpm (p > 0.05). STj depression changed from mean values of 2.7 ± 0.3 mm in the control to 0.9 ± 0.25 mm after treatment (p < 0.001); STy depression changed from mean values of 2.7 ± 0.5 mm in the control to mean values of 0.7 ± 0.06 mm after treatment (p < 0.001). We found-that Mg corrected the STj and STy deviations without a significant alteration of the heart rate. These results indicate that magnesium, improved diltiazem's effect in treating myocardial dyskinesia.