Citations

Background: Evaluation of obese patients with suspected CAD is challenging because obesity is a CV risk factor, but adiposity itself may mimic symptoms of CAD and reduce the accuracy of diagnostic testing. Optimal testing strategies in obese patients are not known. Methods: Patients with stable symptoms suggestive of cardiac ischemia from the PROMISE trial (n=9230) were classified according to BMI. Providers specified a functional test modality prior to stratified randomization to functional (stress testing) or anatomical (CTA) testing. We assessed relationships between BMI, physician’s preference of functional test, test positivity and results of catheter angiography (cath) using logistic regression. Results: Providers were more likely to choose SPECT over other functional tests as BMI increased (OR 1.04 per unit increase in BMI above 27, p<0.001). In patients with BMI ≥ 35 vs. < 35, the rate of positivity with CTA was similar (10% vs. 12%; see Table). The same was true for stress echo and stress ECG (positivity 8-13%, p>0.8 for both). In contrast, SPECT was significantly more likely to be positive in those with BMI ≥ 35 vs. <35 (18% vs. 13%; p=0.001). The likelihood of finding obstructive CAD at cath did not differ with BMI ≥ 35 vs. <35 in patients having CTA (59% vs. 52%, p=0.22), but among SPECT patients, positivity was only 29% with BMI ≥ 35 compared to 52% with BMI < 35 (p=0.005; Table). Conclusions: Increasing levels of obesity were associated with stronger physician preference for SPECT over other noninvasive tests. In patients receiving SPECT, higher levels of obesity were associated with a higher rate of positive results, but a lower cath yield for obstructive CAD. In contrast, in patients receiving CTA, positivity rates and cath yield did not vary by BMI. Obesity appears to significantly influence provider decision-making with regard to noninvasive test choice, probability of abnormal test results and probability of finding obstructive disease at cath.

Background: Patients evaluated for coronary artery disease have a range of symptoms and underlying risk. The relationships between patient-described symptoms, clinician conclusions, and subsequent clinical management and outcomes remain incompletely described. Methods: In this secondary analysis, we examined the association between 4 types of presenting symptoms (substernal/left-sided chest pain, other chest/neck/arm pain, dyspnea, and other symptoms) and patient risk, noninvasive test results, clinical management, and outcomes for stable outpatients randomized in the PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) trial. Multivariable regression models were used to evaluate differences in noninvasive test result, all-cause death/myocardial infarction/unstable angina hospitalization and cardiovascular death/myocardial infarction by symptom type. Results: Among 9996 patients, most presented with chest pain (47.2% substernal, 29.2% other), followed by dyspnea (14.9%), and other symptoms (8.7%). Patients with dyspnea were older (median age 63 versus 60, P ≤0.02) with higher baseline risk (78.2% with atherosclerotic cardiovascular disease >7.5% versus 67.6%, P ≤0.02). Using patients with substernal chest pain as a reference, there was no difference in noninvasive test positivity across symptom groups (all P >0.05), but test-positive patients with dyspnea (adjusted odds ratio, 0.66 [95% CI, 0.51–0.85]) or other symptoms (adjusted odds ratio, 0.65 [95% CI, 0.47–0.90]) were less likely to be referred for cardiac catheterization. While symptom type alone was not associated with outcomes, symptom presentation with chest pain or dyspnea did modify the association between a positive noninvasive test and clinical outcome (interaction P =0.025 for both all-cause death/myocardial infarction/unstable angina hospitalization and cardiovascular death/MI). Conclusions: Among low-risk outpatients evaluated for coronary artery disease, typicality of symptoms was not closely associated with higher baseline risk but was related to differences in processes of care and the prognostic value of a positive test. Adverse events were not associated with clinician risk estimates or symptoms alone. These unexpected findings highlight the limitation of relying solely on symptom presentation or clinician risk estimation to evaluate patients for suspected coronary artery disease. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01174550.

Objective To evaluate informal physician judgement versus pretest probability scores in estimating risk in patients with suspected coronary artery disease (CAD). Methods We included 4533 patients from the PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) trial. Physicians categorised a priori the pretest probability of obstructive CAD (≥70% or ≥50% left main); Diamond-Forrester (D-F) and European Society of Cardiology (ESC) pretest probability estimates were calculated. Agreement was calculated using the κ statistic; logistic regression evaluated estimates of pretest CAD probability and actual CAD (as determined by CT coronary angiography), and clinical outcomes were modelled using Cox proportional hazard models. Results Physician estimates agreed poorly with D-F (κ 0.16; 95% CI 0.14 to 0.18) and ESC (κ 0.04; 95% CI 0.02 to 0.05). Actual obstructive CAD was significantly more prevalent in both the high-likelihood (OR 3.30; 95% CI 2.30 to 4.74) and the intermediate-likelihood (OR 1.43; 95% CI 1.16 to 1.76) physician-estimated groups versus the low-likelihood group; ESC similarly differentiated between the three groups (OR 9.07; 95% CI 2.87 to 28.70; and OR 3.87; 95% CI 1.22 to 12.28). However, using D-F, only the high-probability group differed (OR 2.49; 95% CI 1.74 to 3.54). Only physician estimates were associated with a higher incidence of adjusted death/myocardial infarction/unstable angina hospitalisation in the high-probability versus low-probability group (HR 2.68; 95% CI 1.52 to 4.74); neither pretest probability score provided prognostic information. Conclusions Compared with D-F and ESC estimates, physician judgement more accurately identified obstructive CAD and worse patient outcomes. Integrating physician judgement may improve risk prediction for patients with stable chest pain. Trial registration number NCT01174550 .

Background: Inconclusive noninvasive tests complicate the care of patients with suspected coronary artery disease, but their prevalence and impact on management, outcomes, and costs are not well described. Methods: PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) patients were randomized to stress testing (n=4533) or computed tomographic angiography (CTA; n=4677). We assessed relationships between inconclusive results, subsequent testing, a composite outcome (death, myocardial infarction, or hospitalization for unstable angina), and healthcare expenditures. Results: Overall, 8.0% of tests were inconclusive (9.7% stress, 6.4% CTA). Compared with negative tests, inconclusive tests were more often referred to a second noninvasive test (stress: 14.6% versus 8.5%, odds ratio [OR], 1.91; CTA: 36.5% versus 8.4%, OR, 5.95; P <0.001) and catheterization (stress: 5.5% versus 2.4%, OR, 2.36; CTA: 23.4% versus 4.1%, OR, 6.49; P <0.001), and composite outcomes were higher for both inconclusive tests (stress: 3.7% versus 2.0%, hazard ratio, 1.81, P =0.034; CTA: 5.0% versus 2.2%, hazard ratio, 1.85; P =0.044) and positive tests (stress: 8.3% versus 2.0%, hazard ratio, 3.50; CTA: 9.2% versus 2.2%, hazard ratio, 3.66; P <0.001). Twenty-four–month costs were higher for inconclusive tests than negative tests by $2905 (stress) and $4030 (CTA). Conclusions: Among patients with stable chest pain undergoing a noninvasive test, inconclusive results occurred in 6% of CTA and 10% of stress tests. Compared with those with conclusive negative tests, individuals with inconclusive results more often underwent subsequent testing, had increased medical costs, and experienced worse outcomes. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01174550.

Objectives To test the relationship between increasing severity of obesity, calculated risk and observed outcomes. Methods Patients with symptoms suggestive of coronary artery disease (CAD) (n=10 003) were stratified according to body mass index (BMI). We compared risk factors, pooled risk scores and physicians’ perception of risk. Cox regression tested the association between BMI and (1) presence of obstructive CAD and (2) composite clinical endpoints (death, cardiovascular death, unstable angina hospitalisation and myocardial infarction). Results BMI was ≥30 kg/m2 in 48% of patients and ≥35 in 20%. Increasingly obese patients were younger, female and non-smoking but with higher prevalence of hypertension, diabetes, black race and sedentary lifestyle. Pooled risk estimates of CAD were highest in those with mid-range BMI. In contrast, physicians’ estimation of the likelihood of significant CAD based on clinical impression increased progressively with BMI. For a 10% increase in the Diamond-Forrester probability of CAD, the adjusted OR for obstructive CAD was 1.5 (95% CI 1.4 to 1.5) in patients with BMI <35, but only 1.2 (95% CI 1.1 to 1.3) in those with BMI ≥35 (interaction p<0.001). Framingham Risk Score increased across increasing BMI categories. However, there was a strong and consistent inverse relationship between degree of obesity and all three composite clinical endpoints over a median 25 months of follow-up. Conclusions Despite perceptions of higher risk and higher risk scores, increasingly obese patients had obstructive CAD less frequently than predicted and had fewer adverse clinical outcomes. There is a need for risk assessment tools and guidelines that account for obesity. Trial registration number NCT01174550.

Background The impact of diabetes mellitus on the clinical presentation and noninvasive test ( NIT ) results among stable outpatients presenting with symptoms suggestive of coronary artery disease ( CAD ) has not been well described. Methods and Results The PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) trial enrolled 10 003 patients with known diabetic status, of whom 8966 were tested as randomized and had interpretable NIT results (1908 with diabetes mellitus, 21%). Differences in symptoms and NIT results were evaluated using logistic regression. Patients with diabetes mellitus (versus without) were similar in age (median 61 versus 60 years) and sex (female 54% versus 52%), had a greater burden of cardiovascular comorbidities, and had a similar likelihood of nonchest pain symptoms (29% versus 27%). The Diamond‐Forrester/Coronary Artery Surgery Study score predicted that patients with diabetes mellitus (versus without) had similar likelihood of obstructive CAD (low 1.8% versus 2.7%; intermediate 92.3% versus 92.6%; high 5.9% versus 4.7%). Physicians estimated patients with diabetes mellitus to have a higher likelihood of obstructive CAD (low to very low: 28.3% versus 40.1%; intermediate 63.9% versus 55.9%; high to very high 7.8% versus 4.0%). Patients with diabetes mellitus (versus without) were more likely to have a positive NIT result (15% versus 11%; adjusted odds ratio, 1.23; P =0.01). Conclusions Stable chest pain patients with and without diabetes mellitus have similar presentation and pretest likelihood of obstructive CAD ; however, physicians perceive that patients with diabetes mellitus have a higher pretest likelihood of obstructive CAD , an assessment supported by increased risk of a positive NIT . Further evaluation of diabetes mellitus's influence on CAD assessment is required. Clinical Trial Registration URL : https://www.clinicaltrials.gov . Unique identifier: NCT 01174550.