Ischaemic heart disease

Troponins to guide the use of invasive treatment in ACS ▸ Comparing conservative to invasive treatment in patients with acute coronary syndromes (ACS) treated with tirofiban, early invasive treatment showed an 18% reduction in death/myocardial infarction (MI)/repeat ACS within six months. A total of 2220 patients with ACS were enrolled and 1780 completed the six month follow up with cardiac troponin-I (cTnI) available. Patients with a cTnI concentration of > 0.1 ng/ml experienced a significant reduction in the primary end point with the invasive versus conservative strategy (15.3% v 25.0%; odds ratio (OR) 0.54, 95% confidence interval (CI) 0.40 to 0.73). Patients with cTnI concentrations of < 0.1 ng/ml had no benefit from early invasive management (16.0% v 12.4%; OR 1.4, 95% CI 0.89 to 2.05, p < 0.001 for interaction). Similar results were observed with cTnT.

▴

Why blood pressure falls on cardiopulmonary bypass ▸ Hypotension caused by a reduction in systemic vascular resistance (SVR) is a recognised complication of cardiopulmonary bypass (CPB), and may necessitate the administration of ionotropic drugs. This has traditionally been attributed to a generalised inflammatory response in the extracorporeal circulation. Bradykinin, a potent vasodilator that also increases vascular permeability, may accumulate during cardiopulmonary bypass due to the exclusion of the lungs from the circulation where bradykinin is degraded by angiotensin converting enzyme (ACE), and may thus …