Coronary calcification on invasive angiography and the Agatston score—a single-center experience

Aim: The pattern and severity of coronary artery calcification (CAC) can influence prognosis and outcome in percutaneous coronary intervention. An objective assessment of CAC during invasive angiography may provide additional prognostic information. This study aimed to assess the correlation between the angiographic Birmingham calcium score (BCS) and the Agatston coronary calcium score (CCS) performed as part of single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). Methods: In this retrospective observational study, patients undergoing SPECT-MPI and invasive coronary angiography as part of their routine management were included. BCS was calculated by reviewing angiography images in retrospect by an observer blinded to the SPECT-MPI calcium score. Spearman’s correlation was used to analyze the correlation between BCS and SPECT-MPI. Receiver operating characteristic curve was used to detect cut-off for BCS that would detect clinically significant CAC [> 400 Agatston units (AU)]. Kaplan-Meier was used to report on outcomes at 5 years follow-up. Results: In this cohort of 151 patients, there was a positive correlation between BCS and CCS [Spearman correlation coefficient (r) = 0.558, P < 0.001]. Cumulative BCS of 1 was able to identify clinically significant CAC [area under the curve 0.788, 95% confidence interval (CI) 0.714–0.863]. Cumulative BCS ≥ 3 was associated with major adverse outcomes at 5 years follow-up (log rank P = 0.013). Conclusion: BCS correlates well with established higher CCS. Application of BCS during invasive coronary angiography will aid risk stratification, management, and follow-up with no extra patient involvement, radiation, or costs.