Effect of Oral Vitamin E and C Therapy on Calcineurin Inhibitor Levels in Heart Transplant Recipients

BACKGROUND

A recent prospective trial demonstrated that oral vitamins C and E retard the early progression of transplant-associated coronary arteriosclerosis; as a result, a number of centers have added these agents to their maintenance regimens. This study reviewed the impact of vitamin E and C supplementation on calcineurin inhibitor trough concentrations.

METHODS

A retrospective chart review of the first 29 heart transplant patients prescribed anti-oxidant agents was performed. Twenty-two patients taking cyclosporin A (CsA) and 7 patients taking tacrolimus were prescribed vitamin C (500 mg twice a day) and vitamin E (400 IU twice a day). Serum chemistries and drug levels were measured before and after vitamin therapy was initiated.

RESULTS

The baseline CsA trough concentration (mean +/- SD) was 137 +/- 39 ng/ml and it declined to 99 +/- 54 ng/ml (p = 0.007) after anti-oxidant therapy was initiated. The average percentage decrease in the CsA trough concentration was 30%. No significant changes were seen in the patients taking tacrolimus.

CONCLUSIONS

These data demonstrate that supplementation with the anti-oxidant agents vitamin C and vitamin E decreases CsA concentrations but does not appear to effect tacrolimus concentrations. Although more detailed pharmacokinetic analysis is necessary to clarify the exact mechanism of this interaction, physicians who take care of transplant recipients should be aware that more frequent CsA concentration monitoring is warranted after initiating these anti-oxidant agents.

Precordial ST segment depression predicts a worse prognosis in inferior infarction despite reperfusion therapy. The Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) Study Group

The impact of associated precordial ST segment depression in inferior myocardial infarction on angiographic and clinical outcomes after thrombolytic therapy and selective coronary angioplasty was studied in 583 patients with acute myocardial infarction. Anterior infarction (Group I), inferior infarction with precordial ST segment depression (Group II) and inferior infarction without precordial ST segment depression (Group III) were present in 289, 135 and 159 patients, respectively. Precordial ST segment depression was more frequent in circumflex than right coronary infarct-related arteries (44 [71%] of 62 versus 91 [40%] of 230; p = 0.000). Although acute patency rates were not statistically different, there was a trend toward different patency rates at day 7 (Group I 88%, Group II 84%, Group III 80%; p = 0.089) partly because of insignificantly higher reocclusion rates in inferior infarction without precordial ST segment depression (Group I 11%, Group II 10%, Group III 18%, p = 0.104). Infarct zone regional wall motion (standard deviations/chord) in inferior infarction was lower with precordial ST segment depression, both acutely (Group I -2.8 +/- 0.9, Group II -2.5 +/- 1.2, Group III 2.0 +/- 1.1; p = 0.000) and at day 7 (Group I -2.2 +/- 1.1, Group II -2.3 +/- 1.1, Group III -1.9 +/- 1.3; p = 0.011). Precordial ST segment depression was associated with a lower ejection fraction in inferior infarction both acutely (Group I 47 +/- 11%, Group II 53 +/- 11%, Group III 58 +/- 9%; p = 0.000) and at day 7 (Group I 49 +/- 12%, Group II 53 +/- 10%, Group III 58 +/- 8%; p = 0.000). Complication rates tended to be higher in inferior infarction when precordial ST segment depression was present. Mortality rates for Groups I, II and III were 8%, 6% and 5%, respectively. These results suggest that precordial ST segment depression in inferior infarction predicts a worse ventriculographic and clinical outcome despite reperfusion therapy.