Redistribution of diltiazem in the early postmortem period.

We determined tissue distribution of diltiazem after it was used to treat hypertension in two cases. The postmortem interval was 16 h in both cases. Diltiazem was isolated using liquid-liquid extraction, and it was identified and quantitated using gas chromatography-mass spectrometry (GC-MS) and GC, respectively. In one case, diltiazem concentrations in the lungs and pulmonary vessel blood were 62-82 and 27-30 times higher than right femoral blood, respectively. Although blood was not obtained from the left cardiac chambers, aortic blood showed a 10-times higher level of diltiazem than right femoral venous blood. Diltiazem concentration in blood in the right cardiac chambers was 3.6 times higher than that in right femoral venous blood. In another case, diltiazem concentrations in the lungs were 7.4-7.6 times higher than right femoral venous blood. Blood in the pulmonary arteries, pulmonary veins, left cardiac chambers, and aorta showed 2.0-3.1 times higher levels of diltiazem than right femoral venous blood. Blood in the right cardiac chambers displayed only 1.3 times higher level of diltiazem than right femoral venous blood. Our results strongly suggest that diltiazem accumulated in the lungs and was rapidly redistributed into pulmonary venous blood and then into the left cardiac chambers.