25 CT coronary angiography and COVID-19: inpatient use in acute chest pain service

Introduction CT coronary angiography (CTCA) is a well-validated clinical tool in the evaluation of chest pain. In January 2020 a care pathway was agreed between the cardiology, radiology and emergency departments in our facility to implement a strategy of CTCA as a first line inpatient examination for selected patients with chest pain of low to moderate risk of significant coronary artery disease. Impact on length of stay and clinical outcomes including subsequent invasive angiography and revascularisation were evaluated, including major adverse cardiac events at 30 days. Methods Study design was retrospective. Patients referred for cardiology review between October 2019 and May 2020 with chest pain and/or dyspnoea were broken into three cohorts: a baseline cohort, a cohort with increased CTCA availability and a cohort with increased CTCA availability, but after the national lockdown due to COVID-19 in Ireland. These patients were identified via the Hospital Inpatient Enquiry dataset and correlated with chart review. Statistical analysis was via SPSS. Ethical approval was provided by the research and ethics committee in St. James Hospital, Dublin. Results Between October 2019 and May 2020 513 patients (35.3% female) presented between cohorts 1 (n=179), 2 (n=182), and 3 (n=153). Overall population characteristics, investigations and outcomes are available in table 1. This same information is available for those who underwent CTCA in table 2. Daily rate of ED referral to cardiology increased from 2.32 to 2.46 and 2.73 patients. Overall length of stay between cohorts 1 and 3 decreased from 2.66 days median to 1.71 days (p = 0.014). 73 inpatient CTCA were performed over the 8 month period, increasing from 7.8% overall in cohort 1% to 20.4% in cohort 3 (see figure 1). A history of cerebrovascular/cardiovascular disease was significantly associated with CTCA use (p = 0.00097) in cohort 1. Age (p = 0.0017), hypertension (p=0.001) and history of cerebrovascular/cardiovascular disease (p = 0.0015) were associated with CTCA use in cohort 2. Diabetes (p = 0.037) and history of cerebrovascular/cardiovascular disease (p = 0.000246) were associated with CTCA use in cohort 3. Overall length of stay for the patients undergoing CTCA decreased from a median of 4.2 days in cohort 1 to 2.5 days in cohort 3 (see figure 2), with no increase in 30 days adverse outcomes. Invasive coronary angiography rate dropped from 45.8% to 39% in cohort 2, and to 34.2% in cohort 3 (p = 0.0286). Revascularization was required in 29.6% in cohort 1, 15.9% in cohort 2, and 16.3% in cohort 3 (p = 0.00448). Conclusions This study demonstrated an increase in inpatient CTCA provision. The doubling of proportion of patients investigated by CTCA from 7.8% to 15.4% was associated with a reduction in length of stay from 4.2 days to 1.98 days. The improved efficiency in processing these intermediate rather than high risk patients was maintained during the COVID-19 pandemic, with a continued lower length of stay. A corresponding reduction in the rates of invasive coronary angiography and revascularization was seen, without an increase in 30-day major adverse cardiac events. We envisage our findings to be referenced when encouraging the development of CTCA use within national healthcare systems, particularly in light of the increasing trend towards shortening length of hospital admissions within the context of an international pandemic.