Testing for Coronary Artery Disease in Patients Newly Diagnosed with Heart Failure in Alberta, Canada.

Background: Early identification of coronary artery disease (CAD) in patients newly diagnosed with heart failure (HF) has prognostic and therapeutic implications. We evaluated frequency and predictors of CAD testing in Alberta between April 1, 2004 and March 31, 2023. Methods: Population-level retrospective cohort study using linked administrative health datasets and previously validated case definitions. Results: Of 166,447 adults with newly diagnosed HF, 64.2% first presented in the outpatient setting. Within the first month of diagnosis, patients were most likely to be seen by a primary care physician only (PCP, 41.8%); co-management with PCP and a specialist was the second most common management strategy (31.6%). Within 6-months of diagnosis, 46,143 (27.7%) patients had at least one diagnostic evaluation for CAD; coronary catheterization was more common in patients diagnosed in hospital while non-invasive imaging was more common in non-hospitalized patients. Testing was strongly associated with specialist involvement: 54.4% if co-managed with PCP [aOR 5.19, 95% confidence interval 4.96-5.43], 39.6% if saw specialist alone [aOR 2.86, 2.75- 2.97], and 13.8% if managed by PCP alone [referent]). Although frequency of echocardiography and CAD non-invasive imaging rose sharply in 2017, the majority of patients with new HF in all years were not tested for CAD. Conclusion: Despite its prognostic importance, CAD testing is performed in a minority of patients with newly diagnosed heart failure and is heavily influenced by specialist involvement. Optimizing CAD testing patterns for all patients newly diagnosed with HF should be a priority for clinicians and policy makers.