Novel insights into the pathophysiology of different forms of stress testing.

Background: The impact of different forms of cardiac stress testing (exercise versus pharmacological stress testing) on cardiac wall stress and myocardial ischemia is incompletely understood.

Methods: In a prospective study, 331 consecutive patients with suspected myocardial ischemia referred for nuclear perfusion imaging were enrolled: 266 underwent exercise (bicycle) stress testing and 65 adenosine stress testing. Levels of B-type natriuretic peptide (BNP) measured before and 1 min after stress testing, ischemic ECG changes, and typical angina symptoms were used to compare the 2 testing modalities.

Incremental value of high-sensitivity cardiac troponin T for risk prediction in patients with suspected acute myocardial infarction.

Background: High-sensitivity cardiac troponin assays have better analytical precision and sensitivity than earlier-generation assays when measuring cardiac troponin at low concentrations. We evaluated whether use of a high-sensitivity assay could further improve risk stratification compared with a standard cardiac troponin assay.

Methods: We enrolled consecutive patients presenting with acute chest pain, 30% of whom were diagnosed with acute coronary syndrome.