CTA suitable alternative to ICA for diagnosing coronary artery stenosis
MedWire News: Systematic review findings suggest that 64-slice or higher computed tomography angiography (CTA) shows high sensitivity for identifying patients with significant coronary artery stenosis.
The results are of importance, given that CTA could prevent the use of invasive diagnostic procedures such as invasive coronary angiography (ICA) for excluding stenosis.
"This would provide multiple health and cost benefits, particularly for under-resourced areas where invasive coronary angiography is not always available," say Daniel Paech (Health Technology Analysts Pty Ltd, Balmain, Australia) and co-authors.
The researchers identified 28 studies comparing the diagnostic accuracy of CTA with ICA in 3674 patients with suspected coronary artery disease (CAD). A positive diagnosis was defined as 50% or more stenosis.
CTA sensitivity and negative predictive value (NPV) for diagnosing stenosis at the patient level were high, at 98.2% and 99.0%, respectively. Indeed, NPV was found to exceed 95.0% in 14 of the 18 included studies, and 90.0% in 17 of the 18 studies.
Specificity and median positive predictive value (PPV) were also relatively high, at 81.6% and 90.5%, respectively.
When an overall vessel-level analysis was performed, findings revealed that diagnostic performance of CTA was similar to that seen at the patient level, with sensitivity, specificity, and median PPV and NPV scores of 94.9%, 89.5%, 75.0%, and 99.0%, respectively.
At the individual artery level, overall diagnostic accuracy appeared to be slightly higher in the left main coronary artery and slightly lower in the left anterior descending and circumflex artery.
In all segments, the sensitivity was 91.3%, specificity 94.0%, and median PPV and NPV 69.0% and 99.0%, respectively.
"The high NPV observed at the patient, vessel, and segment level establishes CTA as a highly effective non-invasive alternative to ICA for the exclusion of obstructive coronary artery stenosis," say the authors in the journal BMC Cardiovascular Disorders.
They conclude: "It is unlikely that CTA will replace ICA in assessment for revascularization of patients, particularly as angiography and angioplasty are often performed on the same occasion. However, for those patients who are candidates for standalone diagnosis with ICA, CTA may be a viable alternative."
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By Ingrid Grasmo