Stratification for noninvasive coronary angiography: patient preselection considering atypical angina pectoris, conventional cardiovascular risk assessment, and calcium scoring.

Background: Noninvasive coronary angiography (NCA) is recommended to be applied as a filter before invasive coronary angiography in patients with intermediate cardiovascular risk.

Design: In this prospective single-center study, we validated multislice computed tomography (MSCT) and magnetic resonance imaging (MRI)-based NCA by primarily selecting patients with atypical angina pectoris (AAP).

Methods: In 68 patients (63.6+/-11.4 years) with AAP, the Prospective Cardiovascular Muenster Study score and the Agatston score equivalent (ASE; calcium score) were initially determined for cardiovascular risk assessment. Subsequently, MSCT and MRI-based NCA were performed followed by quantitative invasive coronary angiography for validation. All tests were finally analyzed.

Results: CAD (prevalence 38.2%) was diagnosed in 67.7% of patients at high, 61.5% at intermediate, and 37.8% at low cardiovascular risk according to the Prospective Cardiovascular Muenster Study. CAD was diagnosed in 88.2% of patients with an ASE >or=75th percentile and in 90.9% with an ASE >or=90th percentile. With regard to NCA, patient-based analysis resulted in a sensitivity of 96.2% for MSCT versus 69.2% for MRI, in a specificity of 95.2 versus 64.3%, in a positive predictive value of 97.6 versus 77.1%, in a negative predictive value of 92.6 versus 54.5%, and a diagnostic accuracy of 95.6 versus 66.2% (P<0.05).

Conclusion: In a patient group with a heterogeneous cardiovascular risk, primarily considering AAP allows for effective patient preselection for NCA. This may be optimized by precluding patients with an ASE >or=75th percentile. MSCT rather than MRI may then effectively be involved.