Prognostic value of coronary CT angiography for the prediction of major cardiovascular events

Introduction: The evidence on the prognostic value of coronary CT angiography (CCTA) is increasing, but data on its predictive value over longer periods of follow-up are still scarce. The "warranty time" of a normal CCTA is particularly important since it may impact on the downstream use of other tests. The purpose of this study was to assess the midterm prognostic value of a normal CCTA.

Methods: We followed up 1443 consecutive patients (pts) who underwent CCTA (Dual Source 64 slice) from February 2007 through May 2011. Patients with known coronary artery disease and/or those undergoing CCTA for suspected acute coronary syndrome were excluded from this analysis. The presence of coronary plaque and the severity of stenosis (≥or< 50%) were assessed. Follow-up on major adverse events (all cause mortality, non fatal myocardial infarction or coronary revascularization >90 days after CCTA) was obtained for 1284 patients by telephone interview and/or review of clinical records.

Results: 561 pts (43.7%) had a normal CCTA (without visible plaque), 524 (40.8%) had plaque(s) with <50% stenosis and 199 pts (15.5%) had at least one stenosis ≥50%. During a median follow-up of 2.5 years (interquartile range 2.0-3.4 years, 89% completion rate), 36 events occurred (13 deaths, 2 myocardial infarctions and 21 late revascularizations). The annualized event rates were 0.33% (95% CI: 0.00-0.87%) for patients without plaque on CCTA, 1.00% (95% CI: 0.09-1.9%) for patients with plaques causing <50% stenosis, and 2.28% (95% CI: 0.16-4.40%) for those with stenosis ≥50% (figure).

Conclusions: CCTA provides important and durable prognostic information. Patients with normal CCTA seem to have excellent prognosis up to at least 2.5 years. Patients with nonobstructive CAD have an intermediate risk of events.

Source: congress365.escardio.org