PROMISE: where now for CT coronary angiography.

Abstract

Computed tomography coronary angiography (CTCA) entered clinical practice around 2005, mainly due to advances in computed tomography (CT) technology, namely the introduction of 64-slice CT scanners, which were the first that could image the heart within a few seconds. Two years later, another significant advance was the introduction of prospective gating, which reduced the radiation dose for CTCA by 70% to around 2 mSv.1 Multi-centre clinical trials using this technology demonstrated very good sensitivity and excellent negative predictive value (NPV) for the diagnosis of coronary artery disease (CAD) compared with invasive coronary angiography (ICA).2–4 The positive predictive values (PPVs) for CTCA have generally been less impressive as the degree of coronary stenosis can appear more severe on CTCA than on ICA, mainly because of calcium blooming artefacts. CTCA has been compared with exercise electrocardiogram (ECG), using ICA as the gold standard, and again, CTCA was found to have an excellent NPV of 100% compared with 64% for exercise ECG.5 Furthermore, three American trials demonstrated that the use of CTCA to rule out CAD in patients presenting with chest pain to the emergency room can reduce the length of stay …