Search

OBJECTIVE—To determine the proportion of the population, firstly, with cholesterol ⩾ 5.0 mmol/l and, secondly, with any cholesterol concentration, who might benefit from statin treatment for the following: secondary prevention of coronary heart disease (CHD); primary prevention at CHD risk 30%, 20%, 15%, and 6% over 10 years; and primary prevention at projected CHD risk 20% over 10 years (CHD risk at age 60 years if actual age

Background The NICE guideline for chest pain of recent onset recommends diagnosis of angina based on clinical assessment and estimated likelihood of coronary artery disease (CAD). Pre-test likelihood (PTL) estimates are provided in a simplified table based on the Pryor risk equation. If the PTL of CAD is 90%, further diagnostic testing is not required. If 10%–29% cardiac CT should be offered, if 30%–60% functional imaging, and if 61%–90% coronary angiography. We compared risk estimation methods to determine how much use of the table in an uncritical manner vs use of the full risk equation led to a different referral pattern. We also investigated whether interpolation for risk factor profiles would improve assessment. Methods Data were collected prospectively for all patients referred to the Rapid Access Chest Pain Clinic, Newcastle upon Tyne, between February 2002 and August 2011. For each patient, PTL of CAD was assessed by three methods: (1) Reference to the NICE table based on chest pain (typical or atypical), age in deciles, sex and risk factors—smoking, hyperlipidaemia and diabetes dichotomised into high and low risk. For high risk, all three risk factors needed to be present; otherwise the patient was assumed low risk. (2) As per method one, but risk estimates were interpolated between low and high risk values in the NICE table according to the number of risk factors. (3) Calculation by the Pryor equation which includes, in addition, age in years, prior MI, ECG Q waves, and ST/T changes. Results Out of an initial 7022 patients, 1820 were excluded as they had non-anginal chest pain. This left 5202 patients, 2889 with atypical angina and 2313 with typical angina. The number (%) of patients in the five different risk groups by the three risk assessment methods is given in Abstract 140 table 1. Use of the risk equation compared to the table led to half as many people in the category 90% (Abstract 140 figure 1). The corresponding figures correctly classifying people in the five risk categories using the adapted table were 92.9%, 86.4%, 65.2%, 71.2% and 85.9% respectively (Abstract 140 figure 2). Conclusion Use of the NICE table uncritically for assessing PTL of CAD misclassifies a significant proportion of people for further investigation. It is important to include ECG data, interpolate risk factor information, and take into account actual age when using the table rather than the Pryor equation, use of which takes these factors into account automatically.

Background The NICE clinical guideline for chest pain of recent onset (NCG 95) published in March 2010 recommends diagnosing angina based on clinical assessment and likelihood of coronary artery disease (CAD). If the estimated likelihood of CAD is 61%–90%, coronary angiography should be offered. If 30%–60%, functional imaging should be offered, and if 10%–29%, CT calcium scoring should be offered. We determined the number and types of different investigations to diagnose coronary artery disease in patients referred with suspected cardiac pain before the publication of NCG 95 and compared this with the predicted investigations after the application of the guidelines. Methods Data was collected prospectively in a bespoke database for patients referred to the Rapid Access Chest Pain Clinic, Newcastle upon Tyne, UK. Patients with chest pain of suspected cardiac origin were referred from primary care between February 2002 and March 2010. Patients with previous MI, PCI or CABG were excluded. The analysis comprised 5598 men and women with no past history of coronary disease. Likelihood of CAD was calculated by the Pryor equation using the variables age, sex, type of chest pain (typical or atypical), ECG Q waves, smoking, hyperlipidaemia, diabetes and ST/T changes on ECG. The main outcome measures were actual and predicted future frequency of exercise tests, CT coronary angiograms, functional imaging tests and invasive coronary angiograms by pretest likelihood of coronary artery disease. Results The proportion of the study population before and after the guidelines undergoing exercise testing was 50.1% vs 0.0%; for calcium score/CT coronary angiography 0.0% vs 14.7%; for functional imaging 25.6% vs 13.4%; and for invasive coronary angiography 15.3% vs 25.8%. The proportion not requiring further testing was unchanged (30.0% vs 31.0%). Conclusions Application of NICE CG95 will change the investigation of patients with chest pain substantially. A significant reallocation of resources will be required. Exercise testing will be replaced by anatomic or functional imaging. CT coronary angiography will play an important role and replace functional imaging in some patients. Invasive angiography will take on a more important role in the diagnosis of coronary artery disease. It will, however, empower us to reassure almost a third of referrals that they do not have angina on clinical assessment alone.