The NICE chest pain guideline 1 year on Jane S Skinner Consultant Community Cardiologist The Newcastle upon Tyne Hospitals NHS Foundation Trust The Society for Acute Medicine, 5 th International Conference, Imperial College London 29-30 September 2011
Conflicts of interest Clinical advisor for the NICE chest pain guideline with funding from the National Clinical Guideline Centre for Acute and Chronic Conditions which received funding from the National Institute for Health and Clinical Excellence. The views expressed in this presentation are those of myself, and not necessarily those of the institute
Guideline outline Two diagnostic pathways Acute chest pain: possible acute coronary syndrome Intermittent stable chest pain: possible angina Providing information for patients
Acute chest pain: possible ACS Pre-hospital care ECG Pain relief Aspirin Pulse oximetry and oxygen if necessary Continued monitoring
Acute chest pain Referral to hospital Hospital assessment Hospital management and monitoring Diagnosis
Biomarkers Recommendations using conventional troponin assay Required a high diagnostic sensitivity to rule out ACS
NICE recommendations 1.2.5.1 and 1.2.5.2 Take a blood sample for troponin I or T measurement on initial assessment in hospital. These are the preferred biochemical markers to diagnose acute MI. Take a second blood sample for troponin I or T measurement 10 12 hours after the onset of symptoms.
Diagnostic Accuracy of Cardiac Troponin Assays at Presentation According to Time since Onset of Chest Pain Reichlin T et al. N Engl J Med 2009;361:858-867
Diagnosis of MI with sensitive troponin I measurement Keller T et al. N Engl J Med 2009;361:868-877
Changes in troponin assay High sensitivity assays will lead to earlier rule out protocols for acute MI Evidence is in patients with acute chest pain suspected to be an ACS, not less selected patients Trade off of superior clinical sensitivity for reduced clinical specificity for the diagnosis of acute myocardial injury Diagnosis of MI / unstable angina?
Diagnostic criteria for MI Rise and or fall of troponin with at least one value above 99 th percentile of the URL, together with evidence of myocardial ischaemia with at least one of the following: - Symptoms of ischaemia - ECG changes - Imaging evidence of new loss of viable myocardium or new regional wall motion abnormality Thygesen K et al JACC 2007;50:2173-95
NICE guideline in stable chest pain Angina is usually caused by coronary artery disease (CAD). Making a diagnosis of stable angina caused by CAD in people with chest pain is not always straightforward, and the recommendations aim to guide and support clinical judgement.
The diagnostic sieve Patients with chest pain
Recommendation 1.3.1.1 Diagnose stable angina based on one of the following: clinical assessment alone or clinical assessment plus diagnostic testing (that is, anatomical testing for obstructive CAD and/or functional testing for myocardial ischaemia).
Anginal pain is Intermittent stable chest pain Constricting discomfort in the front of the chest, and or in the neck, shoulders, jaw or arms Precipitated by exertion Relieved by rest or GTN within about 5 minutes Typical angina: Three features Atypical angina; Two features Non-anginal pain: One or none
Patients without established CAD Table 1 Percentage of people estimated to have CAD according to typicality of symptoms, age, sex and risk factors 1 Age Non-anginal CP Atypical angina Typical angina Men Women Men Women Men Women Lo Hi Lo Hi Lo Hi Lo Hi Lo Hi Lo Hi 35 3 35 1 19 8 59 2 39 30 88 10 78 45 9 47 2 22 21 70 5 43 51 92 20 79 55 23 59 4 25 45 79 10 47 80 95 38 82 65 49 69 9 29 71 86 20 51 93 97 56 84 Men aged > 70 years, with typical or atypical symptoms assume > 90% Women aged > 70 years assume 61-90%, except women at high risk with typical symptoms where assume > 90% Take into account any ECG abnormalities 1 Adapted from Pryor DB, Shaw L, McCants CB et al (1993) Value of the history and physical in identifying patients at increased risk of for coronary artery disease. Ann Int Med 118(2):81-90
Risk factors in assessment of pre-test likelihood of CAD High risk Diabetes Smoking Hyperlipidaemia (total cholesterol > 6.47 mmol/litre). Low risk none of these
Patients without established CAD Table 1 Percentage of people estimated to have CAD according to typicality of symptoms, age, sex and risk factors 1 Non-anginal CP Atypical angina Typical angina Age Men Women Men Women Men Women Lo Hi Lo Hi Lo Hi Lo Hi Lo Hi Lo Hi 35 3 35 1 19 8 59 2 39 30 88 10 78 45 9 47 2 22 21 70 5 43 51 92 20 79 55 23 59 4 25 45 79 10 47 80 95 38 82 65 49 69 9 29 71 86 20 51 93 97 56 84 Men aged > 70 years, with typical or atypical symptoms assume > 90% Women aged > 70 years assume 61-90%, except women at high risk with typical symptoms where assume > 90% Take into account any ECG abnormalities 1 Adapted from Pryor DB, Shaw L, McCants CB et al (1993) Value of the history and physical in identifying patients at increased risk of for coronary artery disease. Ann Int Med 118(2):81-90
Distribution of patients with no prior history of coronary artery disease % patients 40 30 in a RACPC (n = 223) 20 10 0 Non anginal < 10% 10-29% 30-60% 61-90% > 90% Estimated likelihood of CAD
Diagnostic testing strategy Estimated likelihood of CAD Investigative strategy < 10% and or non-anginal CP Trust your clinical judgment No further testing for CAD 10-29% Rule out test needed CT calcium +/- angiography 30-60% Uncertainty Non invasive functional imaging 61-90% Rule in test needed Consider invasive coronary angiography > 90% with typical angina Trust your clinical judgment No further diagnostic testing
Investigation for chest pain by pretest likelihood of CAD Count 35 30 25 20 15 10 No test CT Functional imaging Invasive CA 5 0 < 10% 10-29% 30-60% 61-90% > 90% Estimated likelihood of CAD
Investigation if estimated 12 Count 10 likelihood of CAD = 10-29% 8 6 4 2 0 CS = 0 CS = 1 to 400 CS > 400 No ischaemia Ischaemia CT coronary calcium score Functional imaging
Investigation if estimated likelihood of CAD = 30-60% 20 Count 16 12 8 4 0 CT coronary calcium score Functional imaging Invasive coronary angiography
16 Count 14 12 10 8 6 4 2 Investigation if estimated likelihood of CAD = 61-90% 0 No ischaemia Functional imaging Ischaemia CAD -ve CAD +ve Invasive coronary angiography
Recommendation 1.3.4.5 an estimated likelihood of CAD of 61 90% (see recommendation 1.3.3.16), offer non-invasive functional imaging after clinical assessment and a resting 12-lead ECG if: coronary revascularisation is not being considered or invasive coronary angiography is not clinically appropriate or acceptable to the person
16 14 12 10 8 6 4 2 0 Invasive coronary angiography: estimated 12 Typical angina likelihood of CAD = 61-90% 8 Atypical angina 16 14 10 6 4 2 0 Typical angina Atypical angina Count 16 14 12 10 8 6 4 2 0 CAD -ve CAD +ve
12 10 8 6 4 2 Functional imaging: estimated 10 likelihood of CAD = 61 to 90% 6 12 8 4 2 0 Typical angina Atypical angina 0 Typical angina Atypical angina Count 16 14 12 10 8 6 4 2 0 No ischaemia Ischaemia
20 16 Jan to Mar 2011: estimated 20 16 12 8 Count 4 0 14 likelihood of CAD 12 = 61-90% 12 Typical angina Atypical angina 10 8 4 0 Typical angina Atypical angina 8 6 4 2 0 No ischaemia Ischaemia Indeterminate CAD -ve CAD +ve Functional imaging Invasive coronary angiography
Clinical history Reflection Assessment of pre-test likelihood Contemporary prevalence of coronary disease Hospital vs primary care population CT coronary calcium score +/- CT coronary angiogram Diagnostic testing in patients with atypical angina pain and a high pretest likelihood (61-90%)
Summary Personal reflection from experience of implementing the NICE chest pain guideline Acute chest pain, possible ACS High sensitivity troponin Stable chest pain Contemporary prevalence of disease Secondary care vs primary care population Implementation of diagnostic investigation