Coronary Computed Tomography Angiography Results in More Computed Tomography Chest Follow-up for Incidental Findings at 1 Year Relative to Stress-perfusion Cardiac Magnetic Resonance Imaging

Rationale and Objectives: The aim of this study is to elucidate the prevalence and factors associated with follow-up chest computed tomography (CT) imaging in patients undergoing stress-perfusion cardiac magnetic resonance imaging (sCMR) and coronary CT angiography (cCTA). Materials and Methods: Cardiac imaging encounters between January 1, 2015 and May 16, 2020 were selected for analysis. Follow-up was tracked within 1-year of initial cardiac imaging, up to May 16, 2021. Patient demographics, comorbidities, and cardiopulmonary outcomes were also analyzed. Results: Between 2015 and 2020, there were 4024 cCTA and 837 sCMR imaging procedures on unique patients with 1.1% and 0.5% of patients having follow-up CT chest studies within 1 year, respectively. When controlling for patient demographic factors, body mass index, insurance status, smoking history, and comorbid diagnostic codes, there was statistically significant increased odds (adjusted odds ratio [95% confidence interval]: 2.864 [1.129-7.265]) of undergoing follow-up within the cCTA cohort. Pulmonary nodules represented the most common incidental finding, with cCTA associated with higher rates of pulmonary nodules detected on imaging (adjusted odds ratio [95% confidence interval]: 5.947 [4.136-8.552]). sCMR was associated with higher rates of MI, percutaneous coronary intervention, and lung malignancy within 1 year, with no difference in all-cause mortality. Conclusions: Patients undergoing either cCTA and sCMR demonstrated a low prevalence of follow-up CT chest imaging; however, follow-up was 2 times greater after cCTA due to greater pulmonary nodule detection. Potential for follow-up should be considered when evaluating the comparative effectiveness of these modalities, including the impact of follow-up imaging on cost and patient outcomes. Strategies to improve lung nodule detection and characterization at the time of sCMR may provide added value in these patients.