Intermediate Probability Of Coronary Artery Disease Research Articles

Comparative effectiveness of exercise electrocardiography versus exercise echocardiography in women presenting with suspected coronary artery disease: a randomized study.

There is a paucity of randomized diagnostic studies in women with suspected coronary artery disease (CAD). This study sought to assess the relative value of exercise stress echocardiography (ESE) compared with exercise electrocardiography (Ex-ECG) in women with CAD. Accordingly, 416 women with no prior CAD and intermediate probability of CAD (mean pre-test probability 41%), were randomized to undergo either Ex-ECG or ESE. The primary endpoints were the positive predictive value (PPV) for the detection of significant CAD and downstream resource utilization. The PPV of ESE and Ex-ECG were 33% and 30% (P = 0.87), respectively for the detection of CAD. There were similar clinic visits (36 vs. 29, P = 0.44) and emergency visits with chest pain (28 vs. 25, P = 0.55) in the Ex-ECG and ESE arms, respectively. At 2.9 years, cardiac events were 6 Ex-ECG vs. 3 ESE, P = 0.31. Although initial diagnosis costs were higher for ESE, more women underwent further CAD testing in the Ex-ECG arm compared to the ESE arm (37 vs. 17, P = 0.003). Overall, there was higher downstream resource utilization (hospital attendances and investigations) in the Ex-ECG arm (P = 0.002). Using National Health Service tariffs 2020/21 (British pounds) the cumulative diagnostic costs were 7.4% lower for Ex-ECG compared with ESE, but this finding is sensitive to the cost differential between ESE and Ex-ECG. In intermediate-risk women who are able to exercise, Ex-ECG had similar efficacy to an ESE strategy, with higher resource utilization whilst providing cost savings.

Letter by Garcia A, et al. regarding article: Coronary artery disease risk reclassification by a new acoustic-based score

The best cost-effective non-invasive test for the diagnosis of coronary artery disease (CAD) in patients with intermediate pre-test probability (PTP) is unknown. Nevertheless one of the most common non invasive test used is the exercise treadmill testing (ETT) that is the less expensive non-invasive test but with the lowest sensitivity for the diagnosis of CAD, therefore many patients with intermediate PTP will required another non-invasive test with a higher cost and some of them require exposure to radiation. Despite all these measures, an estimated $108.9 billion is spent annually on CAD treatment. Some studies had showed that diastolic dysfunction is associated to CAD. A novel signal-processed surface ECG (MyoVista hsECG) can detection the abnormal myocardial relaxation and therefore identified CAD. The non-invasive acoustic device CADScore V3 algorithm had lower cost compared with any noninvasive test, with a high negative predictive value but not good enough specificity to diagnose CAD, hence should be the first approach in patients with a low and intermediate probability of CAD, and if to this evaluation will added the Myovista hs ECG to detection of CAD, therefore some patients with intermediate PTP could be reclassified into high risk and a better cost-effective decisions could be taken as referring directly to coronary angiography.

Prognostic Value of Coronary CT Angiography With Selective PET Perfusion Imaging in Coronary Artery Disease

ObjectivesThe purpose of this study was to evaluate the prognostic value of sequential hybrid imaging strategy in which positron emission tomography (PET) perfusion imaging is performed selectively in patients with suspected obstructive coronary artery disease (CAD) on coronary computed tomography angiography (CTA). BackgroundCoronary CTA is an accurate diagnostic test for excluding obstructive CAD. However, the positive predictive value is suboptimal. MethodsWe investigated 864 consecutive symptomatic patients with intermediate probability of CAD who adhered to the sequential imaging approach. PET myocardial perfusion imaging using 15O-labeled water during adenosine stress was performed when suspected obstructive stenosis was present on coronary CTA. The major adverse events (AEs) including all-cause mortality, myocardial infarction (MI), and unstable angina pectoris (UAP) were recorded. ResultsDuring a median follow-up of 3.6 years, 16 deaths, 10 MIs, and 5 UAPs occurred. Obstructive CAD was excluded by coronary CTA in 462 (53%) patients who had significantly lower annual AE rate than did patients with suspected obstructive stenosis on coronary CTA (0.4% vs. 1.5%; p = 0.003). The latter underwent PET study, on which 195 (49%) had normal and 207 had abnormal perfusion. The annual rate of AEs was 5 times higher in those with abnormal perfusion than with normal perfusion (2.5% vs. 0.5%; p = 0.004). Patients with normal perfusion had AE rate comparable to patients without obstructive CAD on coronary CTA (p = 0.77). ConclusionsIn patients with suspected CAD obstructive disease can be excluded in 53% of patients by coronary CTA, and these patients have good outcome. About one-half (49%) of the remaining patients have normal perfusion and event rate comparable to patients without obstructive CAD on coronary CTA while patients with ischemia have clearly worse outcome. Sequential approach utilizing anatomical imaging by coronary CTA followed by selective functional perfusion imaging is a feasible strategy to diagnose and risk-stratify patients with suspected CAD.

Prognostic value of coronary artery calcium score in patients with symptoms suggestive of coronary artery disease. Results from the Silesian Calcium Score (SILICAS) study.

INTRODUCTION The prognostic value of coronary artery calcium score (CACS) in symptomatic patients with a suspicion of coronary artery disease (CAD) has been poorly defined. OBJECTIVES The aim of the study was to assess the predictive value of the CACS in the incidence of major adverse coronary events (MACEs) in patients with an intermediate probability of CAD and establish its usefulness as the first-line risk assessment tool. PATIENTS AND METHODS This single-center, observational, prospective study enrolled consecutive symptomaticpatients without a previous diagnosis of CAD, referred to our center for CACS assessment with non-contrast-enhanced cardiac computed tomography (CT). CACS measurements were performed using an electrocardiogram-gated 64-row CT scanner. The CACS measurement was treated as the first‑line noninvasive test. Patients with positive CACS values were divided into 4 subgroups: <100 Agatston units (AU), 100 to 399 AU; 400 to 999 AU; and ≥1000 AU. The incidence of MACEs was analyzed in 2 ways: negative versus positive CACS and by the CACS subgroups. RESULTS We included 588 patients (mean age, 61.1 ±9.7 years; women, 64%). The median follow-up period was 707 days. There were 239 patients (49.3%) with no coronary calcium. In these patients, no MACEs were observed, while in those with positive CACS values, they occurred in 108 patients (30.9%) (P <0.001). The incidence of MACEs was dependent on the CACS values, reaching 91% in those with a CACS of 1000 or higher AU. CONCLUSIONS In selected symptomatic patients with an intermediate probability of CAD, the CACS measurement may be used as the first-line test to assess the risk of MACEs.

Two-Dimensional Speckle-Tracking during Dobutamine Stress Echocardiography in the Detection of Myocardial Ischemia in Patients with Suspected Coronary Artery Disease

Two-dimensional speckle-tracking applied to dobutamine stress echocardiography (DSE) may aid in the detection of coronary artery disease (CAD). The aim of this study was to determine the value of strain, strain rate, and postsystolic strain index (PSI) measured by speckle-tracking during DSE in the evaluation of the presence, extent, and severity of myocardial ischemia. Fifty patients 63±7years of age with intermediate probability of CAD were prospectively recruited. All patients underwent DSE, quantitative positron emission tomographic perfusion imaging, and invasive angiography. Regional peak systolic longitudinal strain, strain rate, and PSI were measured at rest, at a dobutamine dose of 20μg/kg/min, at peak stress, and at early recovery (1min after stress). Obstructive CAD was defined as >75% stenosis or 40% to 75% stenosis combined with either fractional flow reserve<0.80 or abnormal findings on myocardial perfusion positron emission tomography. Obstructive CAD was detected in 22 patients and in 36 of 150 coronary arteries. Strain analyses showed the highest reproducibility at rest, at a dobutamine dose of 20μg/kg/min, and at early recovery. Increased PSI and reduced strain during early recovery were the strongest predictors of obstructive CAD and were associated with the extent, localization, and depth of myocardial ischemia by positron emission tomography. On vessel-based analysis, strain, PSI, and visual analysis of wall motion provided comparable diagnostic accuracy, whereas the combination of strain or PSI with visual analysis provided incremental value over visual analysis alone. Assessment of systolic or postsystolic strain by speckle-tracking echocardiography during early recovery after DSE can help in the detection of hemodynamically significant coronary stenosis compared with visual wall motion analysis alone.

Diagnostic one-stop-shop in suspected coronary artery disease gets closer. Coronary computed tomography angiography based fractional flow reserve.

Diagnostic one-stop-shop in suspected coronary artery disease gets closer. Coronary computed tomography angiography based fractional flow reserve.

Abstract 19179: Prognostic Value of Combined Coronary Computed Tomography Angiography and Positron Emission Tomography Perfusion Imaging in Patients With Suspected Coronary Artery Disease

Objectives: Hybrid imaging using coronary computed tomography angiography (CTA) and positron emission tomography (PET) perfusion imaging accurately detects functionally significant coronary artery disease (CAD), but its optimal clinical use remains unknown. We studied the prognostic significance of strategy utilizing sequential CTA for exclusion of CAD followed by PET perfusion imaging for evaluating functional significance of any suspected obstructive lesions with a hybrid PET-CT device in symptomatic patients with suspected intermediate probability of CAD. Methods: We identified a cohort of 864 consecutive patients undergone hybrid PET-CT for the detection of suspected CAD. All patients had CTA and based on CTA findings, haemodynamic significance of any suspected stenoses was evaluated by PET perfusion imaging using H 2 15 O during adenosine-induced stress. Major adverse cardiac events (MACE) including death, myocardial infarction (MI) and unstable angina pectoris (UAP), were collected from the national healthcare statistics. Results: After exclusion of 97 patients undergone early (&lt; 6 months) revascularization, 767 patients with age of 61 ± 10 years (41% males) were followed-up for a median time of 2.5 years. During the follow-up 6 deaths, 5 MIs and 3 UAPs occurred. In 462 patients, obstructive CAD was excluded based on CTA alone and the remaining patients with suspected stenoses (n=305, 39.8%) underwent PET perfusion imaging. In patients with normal or non-obstructive CTA annual incidence of MACE was only 0.16%, whereas in patients with suspected stenosis based on CTA it was 1.36% (p&lt;0.05 vs. no stenosis). In patients with suspected obstructive lesion based on CTA, patients with normal PET perfusion had significantly lower event rate than patients with ischemia (0.54 vs. 2.78%, p&lt;0.05). Conclusion: In patients with suspected obstructive CAD PET perfusion imaging after CT angiography is able to accurately identify those patients with high risk of future MACE. Sequential use of CTA and PET perfusion imaging appears powerful and safe strategy for targeting therapeutic procedures in high risk individuals.

Restriction of the referral of patients with stable angina for CT coronary angiography by clinical evaluation and calcium score: impact on clinical decision making

To investigate the value of the calcium score (CaSc) plus clinical evaluation to restrict referral for CT coronary angiography (CTCA) by reducing the number of patients with an intermediate probability of coronary artery disease (CAD). We retrospectively included 1,975 symptomatic stable patients who underwent clinical evaluation and CaSc calculation and CTCA or invasive coronary coronary angiography (ICA). The outcome was obstructive CAD (≥50 % diameter narrowing) assessed by ICA or CTCA in the absence of ICA. We investigated two models: (1) clinical evaluation consisting of chest pain typicality, gender, age, risk factors and ECG and (2) clinical evaluation with CaSc. Discrimination of the two models was compared. The stepwise reclassification of patients with an intermediate probability of CAD (10-90 %) after clinical evaluation followed by clinical evaluation with CaSc was assessed by clinical net reclassification improvement (NRI). Discrimination of CAD was significantly improved by adding CaSc to the clinical evaluation (AUC: 0.80 vs. 0.89, P < 0.001). CaSc and CTCA could be avoided in 9 % using model 1 and an additional 29 % of CTCAs could be avoided using model 2. Clinical NRI was 57 %. CaSc plus clinical evaluation may be useful in restricting further referral for CTCA by 38 % in symptomatic stable patients with suspected CAD. • CT calcium scores (CaSc) could proiritise referrals for CT coronary angiography (CTCA) • CaSc provides an incremental discriminatory value of CAD compared with clinical evaluation • Risk stratification is better when clinical evaluation is combined with CaSc • Appropriate use of clinical evaluation and CaSc helps avoid unnecessary CTCA referrals.

Routine use of coronary computed tomography as initial diagnostic test for angina pectoris

Coronary computed tomography (CCT) detects coronary obstruction with high sensitivity and might be useful for diagnosis of angina pectoris. In this pilot study, we sought to prospectively evaluate the performance of CCT as initial work up and determine the significance of this strategy according to the pretest likelihood of having coronary artery disease (CAD). One hundred and eighty patients with chest discomfort and suspected angina were prospectively referred for CCT with a 64-slice CT scan. Invasive coronary angiography (ICA) was performed on the basis of CCT findings (stenosis>50%). Patients were classified into tertiles according to estimated pretest probability of obstructive CAD using the Duke Clinical Score (low, intermediate and high). Strategy failure was defined as unnecessary ICA or major adverse cardiac event (MACE) within 6 months in patients without significant stenosis by CCT. Pretest probability for CAD was 53 ± 29%. Significant stenosis was detected by CCT in 51 patients; 47 (26%) underwent ICA. Sixteen strategy failures were reported: 15 patients (10%) were referred for ICA that did not confirm significant coronary stenosis and one MACE occurred in a patient without significant stenosis by CCT. Strategy failures were 8% in low-probability, 1.7% in intermediate-probability and 15% in high-probability patients (P=0.03). CCT as an initial step for angina diagnosis is most effective in patients with an intermediate probability of CAD. In patients with low or high likelihood, it is associated with a high rate of unnecessary ICA but not with adverse events.

The prognostic value of a normal Tc-99m sestamibi SPECT study in suspected coronary artery disease

Background. Myocardial perfusion is widely used for risk stratification of patients with suspected or known coronary artery disease (CAD). Recent years have seen an increasing demand for screening of such patients. The value of a normal stress thallium-201 scanning is well established. The advent of technetium 99m-sestamibi single photon emission computed tomography (SPECT) has enhanced the profile of nuclear cardiology even further as a reliable test for screening. However, in spite of previous reports, there is paucity of large-scale data regarding the prognostic value of a normal Tc 99m-sestamibi scanning result. Methods. The aim of our study was to assess the incidence of cardiac death and non-fatal myocardial infarction in patients with an intermediate probability of coronary artery disease (CAD). A total of 473 patients with normal stress Tc-99m-sestamibi SPECT were monitored for 30 ± 16 (6 to 56) months to assess serious cardiac events. There were 272 men and 201 women, with a mean age of 56 ± 2 years, of whom 89% had symptoms suggestive of CAD, 65% had an abnormal exercise electrocardiography, 6% had known CAD, and 5% had a high risk of CAD. The average workload was 9.14 metabolic equivalents, peak exercise heart rate was 93% ± 13% of the age predicted target. Results. The annualized mortality rate was 0.2% (95% CI 0.02% to 0.7%) and no infarctions occurred in this group. Conclusions. A normal stress Tc-99m-sestamibi is highly predictive of a benign outcome, even in patients with intermediate probability of CAD.

Clinical applications of exercise nuclear cardiology studies in the era of healthcare reform

The challenge for nuclear cardiology is to demonstrate that it can provide more information than competitive modalities at comparable or lower cost. In considering patients for nuclear cardiology procedures, presentations can be divided into 9 subsets: within each subset, nuclear cardiology tests should be employed where incremental information is provided over the information available without performing the test. (1) Patients with no known coronary artery disease (CAD); for <i>diagnosis</i>, nuclear imaging is useful in patients with intermediate probability of CAD. For <i>prognosis</i>, assessment is based on extent of ischemia, where we have shown that nuclear testing provides incremental information, especially in patients with a high likelihood of CAD, such as those with typical angina. In the remaining categories (2–9), nuclear cardiology studies are predominantly used for purposes of risk stratification. Here the greatest value is in patients deemed to be at intermediate risk before nuclear testing. (2) Postmyocardial infarction: stress nuclear imaging provides an alternative to angiography for risk assessment of clinically uncomplicated patients. (3) Poor ventricular function: Nuclear testing is particularly useful for differentiating patients with hibernating myocardium (the defect is reversible), with stunned myocardium (no defect is present), or with myocardial infarction (the defect is persistent). (4) Unstable angina: Following current federal guidelines, nuclear imaging in medically stabilized low-to-intermediate risk patients with unstable angina is likely to increase. (5) Postcatheterization patients: Nuclear imaging is useful when there is uncertainty regarding the choice of medical management or revascularization. (6) Pre-noncardiac surgery patients: Nuclear imaging is clearly helpful in patients with intermediate clinical risk and may provide useful information in clinically high-risk patients. (7) Post-PTCA patients: Due to the intermediate likelihood of restenosis, nuclear scans are frequently employed 2–6 months following intervention. (8) Post-CABG patients: We have demonstrated that exercise scintigraphy (SPECT) provides incremental prognostic information over clinical and exercise electrocardiographic results and is useful when clinical risk of events is considered intermediate. (9) Long-term management: Scintigraphy provides objective information regarding progression or regression of CAD.

Clinical applications of exercise nuclear cardiology studies in the era of healthcare reform

The challenge for nuclear cardiology is to demonstrate that it can provide more information than competitive modalities at comparable or lower cost. In considering patients for nuclear cardiology procedures, presentations can be divided into 9 subsets: within each subset, nuclear cardiology tests should be employed where incremental information is provided over the information available without performing the test. (1) Patients with no known coronary artery disease (CAD); for diagnosis, nuclear imaging is useful in patients with intermediate probability of CAD. For prognosis, assessment is based on extent of ischemia, where we have shown that nuclear testing provides incremental information, especially in patients with a high likelihood of CAD, such as those with typical angina. In the remaining categories (2-9), nuclear cardiology studies are predominantly used for purposes of risk stratification. Here the greatest value is in patients deemed to be at intermediate risk before nuclear testing. (2) Postmyocardial infarction: stress nuclear imaging provides an alternative to angiography for risk assessment of clinically uncomplicated patients. (3) Poor ventricular function: Nuclear testing is particularly useful for differentiating patients with hibernating myocardium (the defect is reversible), with stunned myocardium (no defect is present), or with myocardial infarction (the defect is persistent). (4) Unstable angina: Following current federal guidelines, nuclear imaging in medically stabilized low-to-intermediate risk patients with unstable angina is likely to increase. (5) Postcatheterization patients: Nuclear imaging is useful when there is uncertainty regarding the choice of medical management or revascularization. (6) Pre-noncardiac surgery patients: Nuclear imaging is clearly helpful in patients with intermediate clinical risk and may provide useful information in clinically high-risk patients. (7) Post-PTCA patients: Due to the intermediate likelihood of restenosis, nuclear scans are frequently employed 2-6 months following intervention. (8) Post-CABG patients: We have demonstrated that exercise scintigraphy (SPECT) provides incremental prognostic information over clinical and exercise electrocardiographic results and is useful when clinical risk of events is considered intermediate. (9) Long-term management: Scintigraphy provides objective information regarding progression or regression of CAD.