Syncope in elderly patients. Why their risk is higher.

The elderly are at increased risk for syncope not only because of physiologic changes due to aging but also because they have a higher incidence of chronic illness and use a greater number of medications that may cause orthostatic hypotension. Although evaluation should emphasize cardiovascular and neurologic components, the cause may remain elusive in as many as 50% of patients.

Outcome of patients with acute myocardial infarction who are ineligible for thrombolytic therapy.

Objective: To determine what proportion of patients with acute myocardial infarction are not eligible for thrombolytic therapy and to assess their natural history.

Design: Retrospective chart review.

Setting: A large community-based hospital.

Long-chain acyl-CoA and acylcarnitine hydrolase activities in normal and ischemic rabbit heart.

Long-chain acyl-CoA and acylcarnitine hydrolase activities were determined in fresh and perfused rabbit heart and correlated with tissue levels of their respective substrates, long-chain acyl-CoA and acylcarnitine. In fresh heart homogenate acyl-CoA hydrolase activity was 3-fold greater than acylcarnitine hydrolase activity; sonication of homogenate doubled acyl-CoA hydrolase activity but did not significantly change acylcarnitine hydrolase activity. Hearts perfused with 10 mM glucose by the nonrecirculating Langendorff method had depressed levels of acyl-CoA hydrolase activity under both aerobic and ischemic conditions.