16 research outputs found
Is there a role for CT coronary angiography in patients with symptomatic angina? Effect of coronary calcium score on identification of stenosis
Present guidelines discourage the use of CT coronary angiography (CTCA) in symptomatic angina patients. We examined the relation between coronary calcium score (CS) and the performance of CTCA in patients with stable and unstable angina in order to understand under which conditions CTCA might be a gate-keeper to conventional coronary angiography (CCA) in such patients. We included 360 patients between 50 and 70 years old with stable and unstable angina who were clinically referred for CCA irrespective of CS. Patients received CS and CCTA on 64-slice scanners in a multicenter cross-sectional trial. The institutional review board approved the study. Diagnostic performance of CTCA to detect or rule out significant coronary artery disease was calculated on a per patient level in pre-defined CS categories. The prevalence of significant coronary artery disease strongly increased with CS. Negative CTCA were associated with a negative likelihood ratio of <0.1 independent of CS. Positive CTCA was associated with a high positive likelihood ratio of 9.4 if CS was <10. However, for higher CS the positive likelihood ratio never exceeded 3.0 and for CS >400 it decreased to 1.3. In the 62 (17%) patients with CS <10, CTCA reliably identified the 42 (68%) of these patients without significant CAD, at no false negative CTCA scans. In symptomatic angina patients, a negative CTCA reliably excludes significant CAD but the additional value of CTCA decreases sharply with CS >10 and especially with CS >400. In patients with CS <10, CTCA provides excellent diagnostic performance
Follow-up of internal mammary artery stent with 64-slice CT
We present a case of 81-year-old woman complaining chest pain after minimal efforts who underwent multiple coronary artery bypass grafts (CABGs) during the last 15 years. A significant in-stent re-stenosis was found at ostium of left internal mammary artery (LIMA). A non-invasive CT coronary angiography (CT-CA) was performed after 6-month follow-up. CT-CA is a reliable non-invasive technique for the follow-up of stents in coronary artery bypass grafts
Incremental value of the CT coronary calcium score for the prediction of coronary artery disease
Objectives:: To validate published prediction models for the presence of obstructive coronary artery disease (CAD) in patients with new onset stable typical or atypical angina pectoris and to assess the incremental value of the CT coronary calcium score (CTCS). Methods:: We searched the literature for clinical prediction rules for the diagnosis of obstructive CAD, defined as≥50% stenosis in at least one vessel on conventional coronary angiography. Significant variables were re-analysed in our dataset of 254 patients with logistic regression. CTCS was subsequently included in the models. The area under the receiver operating characteristic curve (AUC) was calculated to assess diagnostic performance. Results:: Re-analysing the variables used by Diamond & Forrester yielded an AUC of 0.798, which increased to 0.890 by adding CTCS. For Pryor, Morise 1994, Morise 1997 and Shaw the AUC increased from 0.838 to 0.901, 0.831 to 0.899, 0.840 to 0.898 and 0.833 to 0.899. CTCS significantly improved model performance in each model. Conclusions:: Validation demonstrated good diagnostic performance across all models. CTCS improves the prediction of the presence of obstructive CAD, independent of clinical predictors, and should be considered in its diagnostic work-up. © 2010 The Author(s)
A clinical prediction rule for the diagnosis of coronary artery disease: validation, updating, and extension
Aims The aim was to validate, update, and extend the Diamond-Forrester model for estimating the probability of obstructive coronary artery disease (CAD) in a contemporary cohort. Methods and results Prospectively collected data from 14 hospitals on patients with chest pain without a history of CAD and referred for conventional coronary angiography (CCA) were used. Primary outcome was obstructive CAD, defined as ≥50% stenosis in one or more vessels on CCA. The validity of the Diamond-Forrester model was assessed using calibration plots, calibration-in-the-large, and recalibration in logistic regression. The model was subsequently updated and extended by revising the predictive value of age, sex, and type of chest pain. Diagnostic performance was assessed by calculating the area under the receiver operating characteristic curve (c-statistic) and reclassification was determined. We included 2260 patients, of whom 1319 had obstructive CAD on CCA. Validation demonstrated an overestimation of the CAD probability, especially in women. The updated and extended models demonstrated a c-statistic of 0.79 (95% CI 0.77-0.81) and 0.82 (95% CI 0.80-0.84), respectively. Sixteen per cent of men and 64% of women were correctly reclassified. The predicted probability of obstructive CAD ranged from 10% for 50-year-old females with non-specific chest pain to 91% for 80-year-old males with typical chest pain. Predictions varied across hospitals due to differences in disease prevalence. Conclusion Our results suggest that the Diamond-Forrester model overestimates the probability of CAD especially in women. We updated the predictive effects of age, sex, type of chest pain, and hospital setting which improved model performance and we extended it to include patients of 70 years and olde
Individual patient data meta-analysis for the clinical assessment of coronary computed tomography angiography: protocol of the Collaborative Meta-Analysis of Cardiac CT (CoMe-CCT)
Background
Coronary computed tomography angiography has become the foremost noninvasive imaging modality of the coronary arteries and is used as an alternative to the reference standard, conventional coronary angiography, for direct visualization and detection of coronary artery stenoses in patients with suspected coronary artery disease. Nevertheless, there is considerable debate regarding the optimal target population to maximize clinical performance and patient benefit. The most obvious indication for noninvasive coronary computed tomography angiography in patients with suspected coronary artery disease would be to reliably exclude significant stenosis and, thus, avoid unnecessary invasive conventional coronary angiography. To do this, a test should have, at clinically appropriate pretest likelihoods, minimal false-negative outcomes resulting in a high negative predictive value. However, little is known about the influence of patient characteristics on the clinical predictive values of coronary computed tomography angiography. Previous regular systematic reviews and meta-analyses had to rely on limited summary patient cohort data offered by primary studies. Performing an individual patient data meta-analysis will enable a much more detailed and powerful analysis and thus increase representativeness and generalizability of the results. The individual patient data meta-analysis is registered with the PROSPERO database (CoMe-CCT, CRD42012002780).
Methods/Design
The analysis will include individual patient data from published and unpublished prospective diagnostic accuracy studies comparing coronary computed tomography angiography with conventional coronary angiography. These studies will be identified performing a systematic search in several electronic databases. Corresponding authors will be contacted and asked to provide obligatory and additional data. Risk factors, previous test results and symptoms of individual patients will be used to estimate the pretest likelihood of coronary artery disease. A bivariate random-effects model will be used to calculate pooled mean negative and positive predictive values as well as sensitivity and specificity. The primary outcome of interest will be positive and negative predictive values of coronary computed tomography angiography for the presence of coronary artery disease as a function of pretest likelihood of coronary artery disease, analyzed by meta-regression. As a secondary endpoint, factors that may influence the diagnostic performance and clinical value of computed tomography, such as heart rate and body mass index of patients, number of detector rows, and administration of beta blockade and nitroglycerin, will be investigated by integrating them as further covariates into the bivariate random-effects model.
Discussion
This collaborative individual patient data meta-analysis should provide answers to the pivotal question of which patients benefit most from noninvasive coronary computed tomography angiography and thus help to adequately select the right patients for this test
Efficacy and safety of a 12-week outpatient pulmonary rehabilitation program in Post-PE Syndrome
BACKGROUND
The Post-Pulmonary Embolism Syndrome (PPES) comprises heterogeneous entities, including chronic thromboembolic disease with/without pulmonary hypertension (CTEPH/CTEPD), and deconditioning.
OBJECTIVES
To assess underlying physiological determinants of PPES, and efficacy and safety of rehabilitation training in these patients.
METHODS
56 consecutive PE patients with persistent dyspnea and/or functional limitations despite ≥3 months of anticoagulation underwent standardized diagnostic work-up including exercise testing as part of routine practice. All diagnostic (imaging and cardiopulmonary function) tests were interpreted by a core group of experienced clinicians. A subgroup of patients without CTEPH or other treatable conditions was referred for a 12-week personalized rehabilitation program, studying changes in physical condition and patient-reported outcome measures.
RESULTS
Persistent vascular occlusions were observed in 21/56 patients (38%) and CTEPH was confirmed in ten (18%). Regarding those without CTEPH, impaired cardiopulmonary responses were evident in 18/39 patients with available CPET data (46%), unrelated to chronic thrombi. Rehabilitation was completed by 27 patients after excluding 29 (patients with CTEPH or treatable comorbidities, refusal, ineligibility, or training elsewhere). Training intensity, PE-specific quality of life (PEmb-QoL) and fatigue (CIS) improved with a median difference of 20 W (p = 0.001), 3.9 points (p < 0.001) and 16 points (p = 0.003), respectively. Functional status (Post-VTE Functional Status Scale) improved ≥1 grade in 18 (67%) patients, and declined in one (3.7%).
CONCLUSIONS
Our findings suggest that abnormal cardiopulmonary responses to exercise are common in patients with PPES and are not limited to those with chronic thrombi. Offering pulmonary rehabilitation to patients not treated otherwise seems safe and promising
Incremental diagnostic accuracy of hybrid SPECT/CT coronary angiography in a population with an intermediate to high pre-test likelihood of coronary artery disease
Hybrid myocardial perfusion imaging with single photon emission computed tomography (SPECT) and CT coronary angiography (CCTA) has the potential to play a major role in patients with non-conclusive SPECT or CCTA results. We evaluated the performance of hybrid SPECT/CCTA vs. standalone SPECT and CCTA for the diagnosis of significant coronary artery disease (CAD) in patients with an intermediate to high pre-test likelihood of CAD. In total, 98 patients (mean age 62.5 ± 10.1 years, 68.4% male) with stable anginal complaints and a median pre-test likelihood of 87% (range 22-95%) were prospectively included in this study. Hybrid SPECT/CCTA was performed prior to conventional coronary angiography (CA) including fractional flow reserve (FFR) measurements. Hybrid analysis was performed by combined interpretation of SPECT and CCTA images. The sensitivity, specificity, positive (PPV), and negative (NPV) predictive values were calculated for standalone SPECT, CCTA, and hybrid SPECT/CCTA on per patient level, using an FFR 40% of the patients with a high pre-test likelihood no significant CAD was demonstrated, emphasizing the value of accurate pre-treatment cardiovascular imaging. Hybrid SPECT/CCTA was able to accurately diagnose and exclude significant CAD surpassing standalone myocardial SPECT and CCTA, vs. a reference standard of FFR measurement
Added value of hybrid myocardial perfusion SPECT and CT coronary angiography in the diagnosis of coronary artery disease
Hybrid single photon emission computed tomography (SPECT)/coronary computed tomography angiography (CCTA) has only been evaluated for its diagnostic accuracy as a single test in patients suspected of significant coronary artery disease (CAD). Added value of hybrid SPECT/CCTA beyond usual clinical work-up, or use of each of these tests separately, remains unclear. We evaluated the added value of hybrid myocardial perfusion SPECT (SPECT) and CCTA, beyond pre-test likelihood and exercise stress ECG (X-ECG), in the diagnosis of CAD. Two hundred and five patients with stable angina pectoris and intermediate-to-high pre-test likelihood were prospectively included. All patients underwent clinical history and examination, X-ECG, stress and rest SPECT, coronary calcium scoring (CCS) and CCTA. Fractional flow reserve measurement 50% on coronary angiography (CA) served as reference standard for significant CAD. Multiple imputation was used to correct for missing test results (17-20%). Added value of hybrid SPECT/CCTA to the basic model of pre-test likelihood plus X-ECG was quantified using logistic regression analysis. Model differences were then assessed using differences in C-index and in net reclassification improvement (NRI). The basic model had a C-index of 0.73 (95%CI 0.66-0.80). This significantly increased to 0.85 (95%CI 0.80-0.91) by addition of only SPECT, to 0.90 (95%CI 0.85-0.94) when adding only CCTA, and to 0.96 (95%CI 0.92-0.99) when adding hybrid SPECT/CCTA. The accompanying NRIs were 0.82 (95%CI 0.62-1.02), 0.86 (95%CI 0.66-1.06) and 1.57 (95%CI 1.11-1.59) respectively. Current analysis resembles clinical routine of layered testing and shows that hybrid SPECT/CCTA imaging has a substantially higher yield than standalone SPECT or CCTA in the diagnostic workup of patients suspected of significant CA