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Background: Use of pretest probability can reduce unnecessary testing. We hypothesize that quantitative pretest probability, linked to evidence-based management strategies, can reduce unnecessary radiation exposure and cost in low-risk patients with symptoms suggestive of acute coronary syndrome and pulmonary embolism., Methods and Results: This was a prospective, 4-center, randomized controlled trial of decision support effectiveness. Subjects were adults with chest pain and dyspnea, nondiagnostic ECGs, and no obvious diagnosis. The clinician provided data needed to compute pretest probabilities from a Web-based system. Clinicians randomized to the intervention group received the pretest probability estimates for both acute coronary syndrome and pulmonary embolism and suggested clinical actions designed to lower radiation exposure and cost. The control group received nothing. Patients were followed for 90 days. The primary outcome and sample size of 550 was predicated on a significant reduction in the proportion of healthy patients exposed to >5 mSv chest radiation. A total of 550 patients were randomized, and 541 had complete data. The proportion with >5 mSv to the chest and no significant cardiopulmonary diagnosis within 90 days was reduced from 33% to 25% (P=0.038). The intervention group had significantly lower median chest radiation exposure (0.06 versus 0.34 mSv; P=0.037, Mann-Whitney U test) and lower median costs ($934 versus $1275; P=0.018) for medical care. Adverse events occurred in 16% of controls and 11% in the intervention group (P=0.06)., Conclusions: Provision of pretest probability and prescriptive advice reduced radiation exposure and cost of care in low-risk ambulatory patients with symptoms of acute coronary syndrome and pulmonary embolism., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01059500.

Background: Cardiac stress testing in patients at low risk for acute coronary syndrome is associated with increased false-positive test results, unnecessary downstream procedures, and increased cost. We judged it unlikely that patient preferences were driving the decision to obtain stress testing., Methods and Results: The Chest Pain Choice trial was a prospective randomized evaluation involving 204 patients who were randomized to a decision aid or usual care and were followed for 30 days. The decision aid included a 100-person pictograph depicting the pretest probability of acute coronary syndrome and available management options (observation unit admission and stress testing or 24-72 hours outpatient follow-up). The primary outcome was patient knowledge measured by an immediate postvisit survey. Additional outcomes included patient engagement in decision making and the proportion of patients who decided to undergo observation unit admission and cardiac stress testing. Compared with usual care patients (n=103), decision aid patients (n=101) had significantly greater knowledge (3.6 versus 3.0 questions correct; mean difference, 0.67; 95% CI, 0.34-1.0), were more engaged in decision making as indicated by higher OPTION (observing patient involvement) scores (26.6 versus 7.0; mean difference, 19.6; 95% CI, 1.6-21.6), and decided less frequently to be admitted to the observation unit for stress testing (58% versus 77%; absolute difference, 19%; 95% CI, 6%-31%). There were no major adverse cardiac events after discharge in either group., Conclusions: Use of a decision aid in patients with chest pain increased knowledge and engagement in decision making and decreased the rate of observation unit admission for stress testing.

Objective: Although it is well established that plasma B-type natriuretic peptide (BNP) levels are higher in patients with acute coronary syndromes, the relationship between plasma BNP level and stable coronary artery disease is not clear. The aim of this study was to examine the relationship between plasma BNP levels and the extent of obstructive lesions on coronary angiography in stable coronary artery patients., Methods: Plasma BNP concentrations were measured in 62 patients with a diagnosis of stable angina pectoris who had a left ventricular ejection fraction (LVEF) >or=45% on echocardiographic evaluation. Coronary angiography was performed for all patients, who were than divided into two groups according to the results of the angiography. Group I consisted of the patients who had a lesion leading to an obstruction of the lumen in any coronary artery by less than 50% or those who had normal coronary arteries. All other patients constituted group II., Results: In group I (n=26), the mean plasma BNP level was 64.8+/-29.5 pg/ml. In group II (n=36), it was 99.7+/-55.4 pg/ml. BNP was significantly higher in group II (P=0.007) than group I. The BNP concentration of the patients with one-vessel disease (n=12), two-vessel disease (n=16), and three-vessel disease (n=8) were 77.9+/-34.9 pg/ml, 109.3+/-67.9 pg/ml, 113.3+/-48.1 pg/ml consecutively. In this respect, the plasma BNP was significantly higher in the groups with more extended vessel disease (P=0.02). When we compared the patients according to involvement of left anterior descending artery (LAD), BNP levels were significantly higher in this group, (116.1+/-55.8 pg/ml versus 64.1+/-30.2 pg/ml; P=0.001)., Conclusion: Plasma levels of BNP were higher in patients who have stable coronary artery disease with preserved left ventricular systolic function. The level of increase in plasma BNP concentration was positively correlated with the extent of lesion and LAD involvement on coronary angiography.

Controversy still surrounds the use of invasive and noninvasive tests after establishing the clinical diagnosis of stable angina pectoris. The authors employed threshold analysis, a multifactorial mathematical instrument, and the risk and benefit data available in 1983 to determine that the optimal diagnostic approach is to perform a stress test first and then consider angiographic evaluation and surgery for those patients with a positive result. This decision rule was compared with the diagnostic approaches proposed by 61 randomly selected board-certified cardiologists. Fifteen different two-test strategies were proposed by the 61 experts. Fifty-three chose a stress test as the initial procedure and 37 would proceed to coronary angiography if the stress test were positive. Thus a majority of the experts studied (60.6%) proposed an approach identical to the result of threshold analysis. Three respondents thought that no tests were necessary for the evaluation of stable angina pectoris. Twelve cardiologists would not recommend coronary angiography in stable angina patients with unequivocally positive stress tests. Their degree of familiarity and practical experience with the invasive procedure, as well as their perception of risks and benefits of coronary angiography and coronary artery bypass surgery, was not different than that of the cardiologists holding the majority view. For this group the decision analytic model could be used to correct judgmental biases and to optimize the diagnostic evaluation of coronary artery disease.

We determined the outcome of coronary artery bypass surgery in 500 consecutive patients followed for at least 10 years after operation. There were 446 males (89.2%). Angina pectoris was the major indication for operation. Four hundred six patients (81%) had multivessel coronary artery disease and 348 (69.9%) had good left ventricular function. At 10 years of follow-up, 48% of patients were asymptomatic and 41% were improved. Propranolol was being used by 36% of patients and nitrates by 49%. Of the 355 patients younger than 65 years of age at the time of follow-up, 57% were employed full time and 24% were working part-time. Reoperation was performed in 9% of patients. Analysis of survival by Kaplan-Meier curves indicated that overall 10-year survival rates were 78% for one-vessel disease, 69% for two-vessel disease, 48% for three-vessel disease and 67% for left main coronary artery disease. For patients with good left ventricular function, the 10-year survival rates were 83% for one-vessel disease, 73% for two-vessel disease, 53% for three-vessel disease and 73% for left main disease. For patients with poor left ventricular function, the rates were 56%, 59%, 40% and 54%, respectively. Cox multivariate analysis indicated that preoperative diuretic use, history of heart failure, the number of diseased vessels, and infarct on the preoperative ECG were all good predictors of survival. This study shows that the outcome of coronary artery bypass surgery 10 years operation is highly favorable.

Background--Guidelines for the management of patients with suspected coronary artery disease (CAD) rely on the age, sex, and angina typicality-based pretest probabilities of angiographically significant CAD derived from invasive coronary angiography (guideline probabilities). Reliability of guideline probabilities has not been investigated in patients referred to noninvasive CAD testing. Methods and Results--We identified 14048 consecutive patients with suspected CAD who underwent coronary computed tomographic angiography. Angina typicality was recorded with the use of accepted criteria. Pretest likelihood of CAD with ≥50% diameter stenosis (CAD50) and ≥70% diameter stenosis (CAD70) were calculated from guideline probabilities. Computed tomographic angiography images were evaluated by ≥1 expert reader to determine the presence of CAD50 and CAD70. Typical angina was associated with the highest prevalence of CAD50 (40% in men, 19% in women) and CAD70 (27% men, 11% women) compared with other symptom categories (P<0.001 for all). Observed CAD50 and CAD70 prevalences were substantially lower than those predicted by guideline probabilities in the overall population (18% versus 51% for CAD50, 10% versus 42% for CAD70: P<0.001), driven by pronounced differences in patients with atypical angina (15% versus 47% tbr CAD50, 7% versus 37% for CAD71)) and typical angina (29% versus 86% for CAD50, 19% versus 71% for CAD70). Marked overestimation of disease prevalence by guideline probabilities was found at all participating centers and across all sex and age subgroups. Conclusion--In this multinational study of patients referred for coronary computed tomographic angiography, determination of pretest likelihood of angiographically significant CAD by the invasive angiography-based guideline probabilities greatly overestimates the actual prevalence of disease. [ABSTRACT FROM AUTHOR]