European Society of Cardiology-Recommended Coronary Artery Disease Consortium Pretest Probability Scores More Accurately Predict Obstructive Coronary Disease and Cardiovascular Events Than the Diamond and Forrester Score: The Partners Registry

Epicardial Fat Volume Improves the Prediction of Obstructive Coronary Artery Disease Above Traditional Risk Factors and Coronary Calcium Score

BACKGROUND

Recent studies have demonstrated the tremendous potential of epicardial fat volume (EFV) to predict obstructive coronary artery disease. We aimed to develop a new model to estimate pretest probability of obstructive coronary artery disease using traditional risk factors with coronary calcium score and EFV and compare it with proposed models in Chinese patients who underwent coronary computed tomography angiography.

METHODS

The new models were derived from 5743 consecutive patients using multivariate logistic regression and validated in an internal cohort using invasive coronary angiography as the outcome and an external cohort with clinical outcome data. Hosmer-Lemeshow goodness-of-fit test, area under the receiver operating characteristic curve, integrated discrimination improvement and net reclassification improvement were calculated to validate and compare the performance of models.

RESULTS

EFV improved prediction above conventional risk factors and coronary calcium score (area under the receiver operating characteristic curve increased from 0.856 to 0.874, integrated discrimination improvement 0.0487, net reclassification improvement 0.1181, P<0.0001 for all). The final model included 5 predictors: age, sex, symptom, coronary calcium score, and EFV. Good internal validation and external validation of the new model were achieved, with positive net reclassification improvement and integrated discrimination improvement, excellent area under the receiver operating characteristic curve and favorable calibration. Further, the new model demonstrated a better prediction of clinical outcome, resulting in a more cost-effective risk stratification to optimize decision-making of downstream diagnosis and treatment.

CONCLUSIONS

Addition of EFV to conventional risk factors and coronary calcium score offered a more accurate and effective estimation for pretest probability of obstructive coronary artery disease, which may help to improve initial management of stable chest pain.

Comparing the Modified History, Electrocardiogram, Age, Risk Factors, and Troponin Score and Coronary Artery Disease Consortium Model for Predicting Obstructive Coronary Artery Disease and Cardiovascular Events in Patients With Acute Chest Pain

The objective of this study was to compare the History, Electrocardiogram, Age, Risk factors, and Troponin (HEART) score and clinical coronary artery disease (CAD) consortium (CADC) model for predicting obstructive CAD (≥50% stenosis on coronary computed tomographic angiography) and 30-day major adverse cardiovascular events (MACE, composite of acute myocardial infarction, revascularization, and mortality). We studied 1981 patients with no known CAD who presented with acute chest pain and had negative initial troponin and electrocardiogram. Chest pain was classified as typical, atypical, and nonanginal and used to score the history component of the modified HEART score. The C-statistic for predicting obstructive CAD was 0.747 [95% confidence interval (CI), 0.712-0.783] for the HEART score and 0.792 (95% CI, 0.762-0.823) for the CADC model (P = 0.0005). The C-statistic for predicting 30-day MACE was 0.820 (95% CI, 0.774-0.864) for the HEART score and 0.850 (95% CI, 0.800-0.891) for the CADC model (P = 0.11). Among the 48.3% of patients for whom the CADC model predicted ≤5% probability of obstructive CAD, the observed 30-day MACE was 0.6%; among the 48.9% of patients for whom the HEART score was ≤2, the 30-day MACE was 0.6%. In conclusion, the CADC model was more effective at predicting obstructive CAD compared to the HEART score. The HEART score and CADC model were equally effective to safely identify low-risk patients by achieving <1% missed 30-day MACE.

Pre-test probability prediction in patients with a low to intermediate probability of coronary artery disease: a prospective study with a fractional flow reserve endpoint

Aims

European and North American guidelines currently recommend pre-test probability (PTP) stratification based on simple probability models in patients with suspected coronary artery disease (CAD). However, no unequivocal recommendation has yet been established. We aimed to compare the ability of risk factors and different PTP stratification models to predict haemodynamically obstructive CAD with fractional flow reserve (FFR) as reference in low to intermediate probability patients.

Methods and results

We prospectively included 1675 patients with low to intermediate risk who had been referred to coronary computed tomography angiography (CTA). Patients with coronary stenosis were subsequently investigated by invasive coronary angiography (ICA) with FFR measurement if indicated. Discrimination and calibration were assessed for four models: the updated Diamond–Forrester (UDF), the CAD Consortium Basic, the Clinical, and the Clinical + Coronary artery calcium score (CACS). At coronary CTA, 24% of patients were diagnosed with a suspected stenosis and 10% had haemodynamically obstructive CAD at the ICA. Calibration for all CAD Consortium models increased compared with the UDF score. However, all models overestimated the probability of haemodynamically obstructive CAD. Discrimination increased by area under the receiver operating curve from 67% to 86% for UDF vs. CAD Consortium Clinical + CACS. The proportion of low-probability patients (pre-test score < 15%) was for the UDF, CAD Consortium Basic, Clinical, and Clinical + CACS: 14%, 58%, 51%, and 66%, respectively. The corresponding negative predictive values were 97%, 94%, 95%, and 98%, respectively.

Conclusion

CAD Consortium models improve PTP stratification compared with the UDF score, mainly due to superior calibration in low to intermediate probability patients. Adding the coronary calcium score to the models substantially increases discrimination.

Clinical Trials. gov identifier

NCT02264717.

Anatomically and functionally relevant coronary stenoses in patients with normal single-photon emission computed tomography but persistent stable angina

Aims

Single-photon emission computed tomography (SPECT) is widely used for the assessment of coronary artery disease and for decision making regarding revascularization. Concerns about possible false negative findings exist. Our aim was to assess the prevalence of stenoses which are both functionally and anatomically significant in patients referred for invasive fractional flow reserve (FFR) measurements following a normal SPECT, because of persistent complaints.

Methods and results

One hundred and thirty-three consecutive patients with normal SPECT were included, with a total of 180 FFR measurements. Luminal narrowing of ≥70% (≥50% for left main) together with a FFR ≤0.80 denoted an anatomically and functionally significant coronary artery stenosis. Separate analyses were performed for FFR <0.75. Mean age of the patients was 65, 40% were women. Sixteen percent of the study population had both anatomically and functionally significant stenoses. Besides the use of nitrate, no differences in baseline characteristics, symptoms, coronary history, or pre-test likelihood could be identified for the prediction of functionally relevant obstructive coronary disease. If FFR <0.75 was used, only 7.5% of the patients had both anatomically and functionally significant stenoses.

Conclusion

In patients with normal SPECT who undergo FFR measurements because of persistent complaints, the prevalence of stenoses which are both anatomically and functionally significant is low. This suggests that the prevalence of false-negative SPECT is (very) low.

Old and New NICE Guidelines for the Evaluation of New Onset Stable Chest Pain: A Real World Perspective

Stable chest pain is a common clinical presentation that often requires further investigation using noninvasive or invasive testing, resulting in a resource-consuming problem worldwide. At onset of 2016, the National Institute for Health and Care Excellence (NICE) published an update on its guideline on chest pain. Three key changes to the 2010 version were provided by the new NICE guideline. First, the new guideline recommends that the previously proposed pretest probability risk score should no longer be used. Second, they also recommend that a calcium score of zero should no longer be used to rule out coronary artery disease (CAD) in patients with low pretest probability. Third, the new guideline recommends that all patients with new onset chest pain should be investigated with a coronary computed tomographic angiography (CTA) as a first-line investigation. However, in real world the impact of implementation of CTA for the evaluation of new onset chest pain remains to be evaluated, especially regarding its cost effectiveness. The aim of the present report was to discuss the results of the studies supporting new NICE guideline and its comparison with European and US guidelines.

Validity of Coronary Artery Disease Consortium Models for Predicting Obstructive Coronary Artery Disease & Cardiovascular Events in Patients with Acute Chest Pain Considered for Coronary Computed Tomographic Angiography

Although the majority of acute chest pain patients are diagnosed with noncardiac chest pain after noninvasive testing, identifying these low-risk patients before testing is challenging. The objective of this study was to validate the coronary artery disease (CAD) consortium models for predicting obstructive CAD and 30-day major adverse cardiovascular events (MACE) in acute chest pain patients considered for coronary computed tomography angiogram, as well as to determine the pretest probability threshold that identifies low-risk patients with <1% MACE. We studied 1,981 patients with no known CAD and negative initial troponin and electrocardiogram. We evaluated CAD consortium models (basic: age, sex, and chest pain type; clinical: basic + diabetes, hypertension, dyslipidemia, and smoking; and clinical + coronary calcium score [CAC] models) for prediction of obstructive CAD (≥50% stenosis on coronary CT angiogram) and 30-day MACE (Acute Myocardial Infarction, revascularization, and mortality). The C-statistic for predicting obstructive CAD was 0.77 (95% confidence interval [CI] 0.73 to 0.77) for the basic, 0.80 (95% CI 0.77 to 0.80) for the clinical, and 0.88 (95% CI 0.85 to 0.88) for the clinical + CAC models. The C-statistic for predicting 30-day MACE was 0.82 (95% CI 0.77 to 0.87) for the basic, 0.84 (95% CI 0.79 to 0.88) for the clinical, and 0.87 (95% CI 0.83 to 0.91) for the clinical + CAC models. In 47.3% of patients for whom the clinical model predicted ≤5% probability for obstructive CAD, the observed 30-day MACE was 0.53% (95% CI 0.07% to 0.999%); in the 66.9% of patients for whom the clinical + CAC model predicted ≤5% probability, the 30-day MACE was 0.75% (95% CI 0.29% to 1.22%). We propose a chest pain evaluation algorithm based on these models that classify 63.3% of patients as low risk with 0.56% (95% CI 0.15% to 0.97%) 30-day MACE. In conclusion, CAD consortium models have excellent diagnostic and prognostic value for acute chest pain patients and can safely identify a significant proportion of low-risk patients by achieving <1% missed 30-day MACE.

Comparison of International Guidelines for Assessment of Suspected Stable Angina: Insights From the PROMISE and SCOT-HEART

OBJECTIVES

This study sought to compare the performance of major guidelines for the assessment of stable chest pain including risk-based (American College of Cardiology/American Heart Association and European Society of Cardiology) and symptom-focused (National Institute for Health and Care Excellence) strategies.

BACKGROUND

Although noninvasive testing is not recommended in low-risk individuals with stable chest pain, guidelines recommend differing approaches to defining low-risk patients.

METHODS

Patient-level data were obtained from the PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) and SCOT-HEART (Scottish Computed Tomography of the Heart) trials. Pre-test probability was determined and patients dichotomized into low-risk and intermediate-high-risk groups according to each guideline's definitions. The primary endpoint was obstructive coronary artery disease on coronary computed tomography angiography. Secondary endpoints were coronary revascularization at 90 days and cardiovascular death or nonfatal myocardial infarction up to 3 years.

RESULTS

In total, 13,773 patients were included of whom 6,160 had coronary computed tomography angiography. The proportions of patients identified as low risk by the American College of Cardiology/American Heart Association, European Society of Cardiology, and National Institute for Health and Care Excellence guidelines, respectively, were 2.5%, 2.5%, and 10.0% within PROMISE, and 14.0%, 19.8%, and 38.4% within SCOT-HEART. All guidelines identified lower rates of obstructive coronary artery disease in low- versus intermediate-high-risk patients with a negative predictive value of ≥0.90. Compared with low-risk groups, all intermediate-high-risk groups had greater risks of coronary revascularization (odds ratio [OR]: 2.2 to 24.1) and clinical outcomes (OR: 1.84 to 5.8).

CONCLUSIONS

Compared with risk-based guidelines, symptom-focused assessment identifies a larger group of low-risk chest pain patients potentially deriving limited benefit from noninvasive testing. (Scottish Computed Tomography of the Heart Trial [SCOT-HEART]; NCT01149590; Prospective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550).

Coronary calcium score improves the estimation for pretest probability of obstructive coronary artery disease and avoids unnecessary testing in individuals at low extreme of traditional risk factor burden: validation and comparison of CONFIRM score and genders extended model

BACKGROUND

Reliability of models for estimating pretest probability (PTP) of obstructive coronary artery disease (CAD) has not been investigated in individuals at low extreme of traditional risk factor (RF) burden. Thus, we sought to validate and compare CONFIRM score and Genders extended model (GEM) among these individuals.

METHODS

We identified symptomatic individuals with 0 or 1 RF who underwent coronary calcium scan and coronary computed tomographic angiography (CCTA). Follow-up clinical data were also recorded. PTP of obstructive CAD for every individual was estimated according to CONFIRM score and GEM, respectively. Area under the receiver operating characteristic curve (AUC), integrated discrimination improvement (IDI), net reclassification improvement (NRI) and Hosmer-Lemeshow (H-L) test were used to assess the performance of models.

RESULTS

There were 1201 individuals with 0 RF and 2415 with 1 RF. The AUC for GEM was significantly larger than that for CONFIRM score, no matter in individuals with 0 (0.843 v.s. 0.762, p < 0.0001) or 1 (0.823 v.s. 0.752, p < 0.0001) RF. Compared to CONFIRM score, GEM demonstrated positive IDI (5% in individuals with 0 RF and 8% in individuals with 1 RF), positive NRI (41.50% in individuals with 0 RF and 40.19% in individuals with 1 RF), better prediction of clinical events and less discrepancy between observed and predicted probabilities, resulting in a significant decrease of unnecessary testing, especially in negative individuals.

CONCLUSION

In individuals at low extreme of traditional RF burden of CAD, the addition of coronary calcium score provided a more accurate estimation for PTP and application of GEM instead of CONFIRM score could avoid unnecessary testing.

New Algorithm for the Prediction of Cardiovascular Risk in Symptomatic Adults with Stable Chest Pain

PURPOSE OF REVIEW

To review the landmark studies in predicting obstructive coronary artery disease (CAD) in symptomatic patients with stable chest pain and identify better prediction tools and propose a simplified algorithm to guide the health care providers in identifying low risk patients to defer further testing.

RECENT FINDINGS

There are a few risk prediction models described for stable chest pain patients including Diamond-Forrester (DF), Duke Clinical Score (DCS), CAD Consortium Basic, Clinical, and Extended models. The CAD Consortium models demonstrated that DF and DCS models overestimate the probability of CAD. All CAD Consortium models performed well in the contemporary population. PROMISE trial secondary data results showed that a clinical tool using readily available ten very low-risk pre-test variables could discriminate low-risk patients to defer further testing safely. In the contemporary population, CAD Consortium Basic or Clinical model could be used with more confidence. Our proposed simple algorithm would guide the physicians in selecting low risk patients who can be managed conservatively with deferred testing strategy. Future research is needed to validate our proposed algorithm to identify the low-risk patients with stable chest pain for whom further testing may not be warranted.

Predictors of severe stenosis at invasive coronary angiography in patients with normal myocardial perfusion imaging

Purpose

Normal myocardial perfusion imaging (MPI) is associated with excellent prognosis. However, in patients with persisting symptoms, it may be difficult to determine the patients in whom invasive angiography is justified to rule out false negative MPI. We evaluated predictors for severe stenosis at invasive angiography in patients with persisting symptoms after normal MPI.

Methods

229 consecutive patients with normal MPI, without previous bypass surgery, underwent invasive angiography within 6 months. Older age was defined as >65 years. Multivariable analyses were performed to adjust for differences in baseline variables.

Results

Mean age was 62 ± 11 years, 48% were women. Severe stenosis was observed in 34%, and of these patients 60% had single-vessel disease (not left main coronary artery disease). After adjusting for several variables, including diabetes, smoking status, hypertension and hypercholesterolaemia, predictors of severe stenosis were male gender, odds ratio (OR) 2.7 (95% confidence interval (CI) 1.5–4.9), older age, OR 1.9 (95% CI 1.02–3.54) previous PCI, OR 2.0 (95% CI 1.0–4.3) and typical angina, OR 2.5 (95% CI 1.4–4.6).

Conclusions

Increasing age, male gender, previous PCI and typical symptoms are predictors of severe stenosis at invasive coronary angiography in patients with normal MPI. The majority of these patients have single-vessel disease.

High-Sensitivity Cardiac Troponin I and the Diagnosis of Coronary Artery Disease in Patients With Suspected Angina Pectoris

BACKGROUND

We determined whether high-sensitivity cardiac troponin I can improve the estimation of the pretest probability for obstructive coronary artery disease (CAD) in patients with suspected stable angina.

METHODS AND RESULTS

In a prespecified substudy of the SCOT-HEART trial (Scottish Computed Tomography of the Heart), plasma cardiac troponin was measured using a high-sensitivity single-molecule counting assay in 943 adults with suspected stable angina who had undergone coronary computed tomographic angiography. Rates of obstructive CAD were compared with the pretest probability determined by the CAD Consortium risk model with and without cardiac troponin concentrations. External validation was undertaken in an independent study population from Denmark comprising 487 patients with suspected stable angina. Higher cardiac troponin concentrations were associated with obstructive CAD with a 5-fold increase across quintiles (9%-48%; P<0.001) independent of known cardiovascular risk factors (odds ratio, 1.35; 95% confidence interval, 1.25-1.46 per doubling of troponin). Cardiac troponin concentrations improved the discrimination and calibration of the CAD Consortium model for identifying obstructive CAD (C statistic, 0.788-0.800; P=0.004; χ2=16.8 [P=0.032] to 14.3 [P=0.074]). The updated model also improved classification of the American College of Cardiology/American Heart Association pretest probability risk categories (net reclassification improvement, 0.062; 95% confidence interval, 0.035-0.089). The revised model achieved similar improvements in discrimination and calibration when applied in the external validation cohort.

CONCLUSIONS

High-sensitivity cardiac troponin I concentration is an independent predictor of obstructive CAD in patients with suspected stable angina. Use of this test may improve the selection of patients for further investigation and treatment.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01149590.

Identification of patients with stable chest pain deriving minimal value from coronary computed tomography angiography: An external validation of the PROMISE minimal-risk tool

BACKGROUND

The PROspective Multicenter Imaging Study for Evaluation of chest pain (PROMISE) minimal-risk tool was recently developed to identify patients with suspected stable angina at very low risk of coronary artery disease (CAD) and clinical events. We assessed the external validity of this tool within the context of the Scottish Computed Tomography of the HEART (SCOT-HEART) multicenter randomised controlled trial of patients with suspected stable angina due to coronary disease.

METHODS

The minimal-risk tool was applied to 1764 patients with complete imaging and follow-up data. External validity was compared with the guideline-endorsed CAD Consortium (CADC) risk score and determined through tests of model discrimination and calibration.

RESULTS

A total of 531 (30.1%, mean age 52.4years, female 62.0%) patients were classified as minimal-risk. Compared to the remainder of the validation cohort, this group had lower estimated pre-test probability of coronary disease according to the CADC model (30.0% vs 47.0%, p<0.001). The PROMISE minimal-risk tool improved discrimination compared with the CADC model (c-statistic 0.785 vs 0.730, p<0.001) and was improved further following re-estimation of covariate coefficients (c-statistic 0.805, p<0.001). Model calibration was initially poor (χ2 197.6, Hosmer-Lemeshow [HL] p<0.001), with significant overestimation of probability of minimal risk, but improved significantly following revision of the PROMISE minimal-risk intercept and covariate coefficients (χ2 5.6, HL p=0.692).

CONCLUSION AND RELEVANCE

Despite overestimating the probability of minimal-risk, the PROMISE minimal-risk tool outperforms the CADC model with regards to prognostic discrimination in patients with suspected stable angina, and may assist clinicians in decisions regarding non-invasive testing.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01149590.

A simple prediction model to estimate obstructive coronary artery disease

BACKGROUND

A simple noninvasive model to predict obstructive coronary artery disease (OCAD) may promote risk stratification and reduce the burden of coronary artery disease (CAD). This study aimed to develop pre-procedural, noninvasive prediction models that better estimate the probability of OCAD among patients with suspected CAD undergoing elective coronary angiography (CAG).

METHODS

We included 1262 patients, who had reliable Framingham risk variable data, in a cohort without known CAD from a prospective registry of patients referred for elective CAG. We investigated pre-procedural OCAD (≥50% stenosis in at least one major coronary vessel based on CAG) predictors.

RESULTS

A total of 945 (74.9%) participants had OCAD. The final modified Framingham scoring (MFS) model consisted of anemia, high-sensitivity C-reactive protein, left ventricular ejection fraction, and five Framingham factors (age, sex, total and high-density lipoprotein cholesterol, and hypertension). Bootstrap method (1000 times) revealed that the model demonstrated a good discriminative power (c statistic, 0.729 ± 0.0225; 95% CI, 0.69-0.77). MFS provided adequate goodness of fit (P = 0.43) and showed better performance than Framingham score (c statistic, 0.703 vs. 0.521; P < 0.001) in predicting OCAD, thereby identifying patients with high risks for OCAD (risk score ≥ 27) with ≥70% predictive value in 68.8% of subjects (range, 37.2-87.3% for low [≤17] and very high [≥41] risk scores).

CONCLUSION

Our data suggested that the simple MFS risk stratification tool, which is available in most primary-level clinics, showed good performance in estimating the probability of OCAD in relatively stable patients with suspected CAD; nevertheless, further validation is needed.

The 2016 update to NICE CG95 guideline for the -investigation of new onset stable chest pain: more -innovation, but at a cost?

The National Institute for Health and Care Excellence (NICE) published an update on its guideline on chest pain of recent onset in 2016. The new guideline makes three key changes to the 2010 version. NICE recommend that the previously proposed pre-test probability risk score should no longer be used. They also recommend that a calcium score of zero should no longer be used to rule out coronary artery disease in patients with low pre-test probability. However, the most radical change is that NICE now recommend that all patients with new onset chest pain should be investigated with a computerised tomography coronary angiogram as a first-ine investigation. We discuss the recent trial evidence that has informed the NICE update and consider the impact of the new guidelines.

Prognostic Value of High-Sensitivity Cardiac Troponin T Compared with Risk Scores in Stable Cardiovascular Disease

BACKGROUND

Risk stratification of patients with cardiovascular disease remains challenging despite consideration of risk scores.

METHODS

We aimed to evaluate the prognostic performance of high-sensitivity cardiac troponin T in a low-risk outpatient population presenting for nonsecondary and secondary prevention. All-cause mortality, a composite of all-cause mortality, acute myocardial infarction, and stroke (end point 2), and a composite of all-cause mortality, acute myocardial infarction, stroke and rehospitalization for acute coronary syndrome, and decompensated heart failure (end point 3) were defined. The prognostic performance of high-sensitivity cardiac troponin T on index visit was compared with the PROCAM score and 3 FRAMINGHAM subscores.

RESULTS

In 693 patients with a median follow-up of 796 days, we observed 16 deaths, 32 patients with end point 2, and 83 patients with end point 3. All risk scores performed better in the prediction of all-cause mortality in nonsecondary prevention (area under the curve [AUC]: PROCAM: 0.922 vs 0.523, P = .001, consistent for all other scores). In secondary prevention, high-sensitivity cardiac troponin T outperformed all risk scores in the prediction of all-cause mortality (ΔAUC: PROCAM: 0.319, P <.001, consistent for all other scores) and performed superiorly in the prediction of end point 2 compared with the PROCAM, FRAMINGHAM-Coronary Heart Disease, and FRAMINGHAM-Hard Coronary Heart Disease scores (ΔAUC: PROCAM: 0.176, P = .047, consistent for FRAMINGHAM-Coronary Heart Disease and FRAMINGHAM-Hard Coronary Heart Disease). In nonsecondary prevention, we observed a comparable prognostic performance of high-sensitivity cardiac troponin T and multivariable risk scores. Our findings on the prediction of all-cause mortality compared with the FRAMINGHAM-Hard Coronary Heart Disease score were confirmed in an independent validation cohort on 2046 patients.

CONCLUSIONS

High-sensitivity troponin T provides excellent risk stratification regarding all-cause mortality and all-cause mortality, acute myocardial infarction, and stroke in a secondary prevention cohort in whom risk scores perform poorly.

National Institute for Health and Care Excellence updates the stable chest pain guideline with radical changes to the diagnostic paradigm

In the 2016 update of the stable chest pain guideline, the National Institute for Health and Care Excellence (NICE) has made radical changes to the diagnostic paradigm that it-like other international guidelines-had previously placed at the centre of its recommendations. No longer are quantitative assessments of the disease probability considered necessary to determine the need for diagnostic testing and the choice of test. Instead, the recommendation is for no diagnostic testing if chest pain is judged to be 'non-anginal' and CT coronary angiography (CTCA) in patients with 'typical' or 'atypical' chest pain with additional perfusion imaging only if there is uncertainty about the functional significance of coronary lesions. The new emphasis on anatomical-as opposed to functional-testing is driven in large part by cost-effectiveness analysis and despite inevitable resource implications NICE calculates that annual savings for the population of England will be significant. In making CTCA the default diagnostic testing strategy in its updated chest pain guideline, NICE has responded emphatically to calls from trialists for CTCA to have a greater role in the diagnostic pathway of patients with suspected angina.