108 Clinical outcome and cost-effectiveness of performing cardiac investigations in a very low likehood of coronary artery disease population according to nice and esc risk prediction models

Background The NICE (National Institute for Health and Care Excellence) guidance for the management of recent-onset chest pain in 2010, recommended no routine cardiac investigations for patients with risk of coronary artery disease (CAD) less than 10%. The ESC (European Society of Cardiology) guidelines for stable angina in 2013, proposed no further testing in patients with a pretest probability below 15%. The management of patients with very low risk for CAD can be challenging, particularly when there is high clinical suspicion, family history of premature CAD (FHCAD) or ethnicity background with high prevalence of CAD. We sought to evaluate the clinical and economic impact of performing tests to diagnose CAD in this population. Methods We retrospectively analysed patients with very low risk for CAD who attended rapid access chest pain clinic (RACPC) due to recent onset chest pain. The likelihood of CAD was estimated by the NICE modified Diamond-Forrester formula and the ESC pretest probability formula and it was below 10% and 15% respectively. According to the guidelines, no further investigations are recommended for this group. Patients underwent exercise ECG (ExECG) or/and stress echocardiography (SE) mainly due to increased clinical suspicion. Coronary Angiography (CA) was subsequently performed, if it was clinically indicated. This population was followed-up for all-cause mortality, myocardial infarction (MI) and revascularisation. Cost-analysis was also performed. Results Over a period of 12 months, 279 patients underwent ExECG [171 (61,3%) negative, 13 (4,6%) positive and 56 (20%) inconclusive] or/and SE [72 (25,8%) negative and 5 (1.7%) positive]. Coronary angiography performed in 26 patients (9.3%) and significant CAD was identified in one patient (0.3%). Regarding risk factors, 88 (31.5%) patients had FHCAD, 66 (23.6%) hypertension, 30 (10.7%) dyslipidaemia, 17 (6.1%) diabetes and 10 (3.5%) were smokers. The ethnicity distribution predominantly consisted of South Asians (49.8%). Over 55 months (4.5 years)±5 months of follow up, two patients were diagnosed with myocardial infarction (0.7%) but only one had significant CAD and subsequent revascularisation (0.3%). Both patients had ExECG initially which was negative. Also, two patients died (0.7%) both from non-cardiovascular cause. A total cost of £69,060 was spent in these tests with a mean cost of £247 per patient. Conclusion The above findings support the rationale of avoiding further cardiac investigations in patients who are at very low risk of CAD as it is recommended by NICE and ESC guidelines. The cost-effectiveness of this strategy is well-depicted in previous studies and our findings are consistent with these results. Current guidance for the management of these patients seems that it is reassuringly applicable in ethnicities with high prevalence of CAD.