Fatal and non-fatal myocardial infarction in patients with possible angina referred for rapid outpatient assessment

Introduction Rapid access chest pain clinics facilitate the prompt review of patients with symptoms of exertional chest pain suggestive of angina, with the aim of accelerating diagnosis and reducing myocardial infarction and cardiovascular death. Our objective was to systematically evaluate care and outcomes for patients referred to this service. Method This was a retrospective longitudinal cohort study using routinely collected healthcare data of consecutive patients referred from 120 primary care practices across South-East Scotland to a rapid access chest pain clinic. Referred patients were stratified according to whether they were seen at a rapid access nurse-led chest pain clinic or redirected to a general cardiology clinic or were not seen (did not attend or required urgent care prior to outpatient assessment). The primary outcome was fatal or non-fatal myocardial infarction within 1 year of referral. Key secondary outcomes included attendance at the Emergency Department, unscheduled coronary revascularisation, or cardiac death at one year. Results From January 2010 to June 2022, 12,900 patients (median age 61 [inter quartile range 53-69] years, 46% female) were referred to the rapid access chest pain clinic. Of these, 11,060 (85.7%) patients were reviewed at the clinic (4 [2-7] days), 990 (7.7%) were reviewed at the general cardiology clinic (15 [3-49] days) and 850 (6.6%) were not seen. Fatal or non-fatal myocardial infarction occurred in 320 (2.9%) and 40 (3.5%) patients seen at the rapid access and general cardiology clinics respectively, and in 90 (10.6%) patients who were not seen (P<0.001) (Figure 1). Patients referred but not seen were more likely to have fatal or non-fatal myocardial infarction compared to those seen at the rapid access clinic after adjusting for age, sex, hypertension, diabetes and previous myocardial infarction (adjusted odd’s ratio 3.4 [95% confidence interval 2.5-4.5; P<0.001]). Patients referred but not seen were more likely than those assessed in the rapid access clinic to attend the Emergency Department (48% versus 29%; P<0.001) or undergo unscheduled revascularisation (6.5% versus 2.1%; P<0.001) at 1 year, or to have a cardiac death (5.0% versus 3.0%; P=0.005) during the study period. Conclusion Most patients with possible angina referred for rapid outpatient assessment are seen within 4 days and have good outcomes, but a significant proportion experience fatal or non-fatal myocardial infarction or require unscheduled acute care prior to outpatient review. Better risk stratification tools at the point of referral are required to identify those who would benefit from urgent same day assessment.Figure 1