Interobserver variability in the classification of congenital coronary abnormalities: A substudy of the ANOCOR registry

Objectives We studied the observer variability in the description and classification of anomalous connections of the coronary arteries (ANOCOR) between a non-expert group of physicians (ANOCOR investigators) and a group of expert physicians, using the ANOCOR cohort. Background The diagnosis of ANOCOR requires an appropriate identification for the management of the patients involved. A misdiagnosis may have serious repercussions for the management to come. For example a subpulmonic course is sometimes interpreted as an interarterial course ( Fig. 1 ). Methods Consecutive patients identified by 71 referring cardiologists (ANOCOR investigators) were included in the ANOCOR cohort. ANOCOR was diagnosed by invasive and/or computed tomography (CT) coronary angiography. Angiographic images were reviewed by an angiographic committee with experience in the ANOCOR field. Both ANOCOR investigators and angiographic committee filled out a questionnaire to classify each ANOCOR with the type of coronary artery involved, the site of anomalous connection, and the initial course. Observer variability between ANOCOR investigators and angiographic committee was assessed by κ statistics. ANOCOR with an interarterial course were defined as at-risk. Results In total, 496 ANOCOR were identified among 472 patients of the ANOCOR cohort and an interarterial course was present in 31% of the abnormalities. The agreement for the type of artery was excellent (κ = 0.92, 95% CI: 0.86–0.98, P P P P Table 1 ). Conclusions Observer variability in the assessment of ANOCOR between non-experienced and experienced physicians can be significant. We found that expert physicians provide a more robust classification of ANOCOR in comparison with non-expert physicians. Therefore, referral to physicians with a relevant experience should be considered, especially if an ANOCOR at-risk is suspected.