Interdisciplinary Rendez-Vous Approach in Endovascular Stroke Treatment: A New Concept to Accelerate Mechanical Thrombectomy in Primary Stroke Centers.

PURPOSE: Prompt endovascular treatment of patients with stroke due to intracranial Large Vessel Occlusion (LVO) is a major challenge in rural areas because neurointerventionalists are usually not available. As a result, treatment is delayed, and clinical outcomes are worse compared with patients primarily treated in comprehensive stroke centers (CSC). To address this problem, we present a concept in which interdisciplinary, on-site endovascular treatment is performed in a Primary Stroke Center (PSC) by a team of interventional neuroradiologists and cardiologists: the Rendez-Vous approach. METHODS: Thirty-five patients with LVO who underwent interdisciplinary thrombectomy on-site at the PSC as part of the Rendez-Vous concept were compared with 72 patients who were transferred from a PSCs to the CSC for thrombectomy when diagnosed with LVO in terms of temporal sequences and clinical outcomes. RESULTS: Patients treated on-site at the PSC as part of the Rendez-Vous approach were managed as successfully and without an increase in complication rates compared with patients treated secondarily at a CSC (91.7% successful interventions in Rendez-Vous vs. 87.3% in control group, p = 0.57). The time from diagnosis of LVO to groin puncture was reduced by mean 74.3 min with the Rendez-Vous concept (p < 0.01). Regarding the clinical outcome, a functionally independent status was achieved in 45.5% in the Rendez-Vous group and in 22.6% in the control group (p = 0.029). CONCLUSION: Thanks to interdisciplinary teamwork between cardiology and interventional neuroradiology in local PSCs, times to successful reperfusion can be reduced. This has a potentially positive impact on the clinical outcome of stroke patients.

Coronary calcifications detected by computed tomography are not markers of cardiac allograft vasculopathy.

BACKGROUND: Cardiac allograft vasculopathy (CAV) still limits survival after heart transplantation. Currently available noninvasive tests are of inferior value to detect CAV, and thus invasive coronary angiography (ICA) is frequently performed. Cardiac dual-source computed tomography calcium scoring (DSCTCS) offers the possibility to detect coronary calcifications, which might serve as a noninvasive marker of CAV. This study sought to evaluate its clinical feasibility. METHODS: One hundred sixty-one patients (130 men; 31 women; mean age: 50.5±12.1 years) underwent DSCTCS 1±2 days before annual routine ICA. Mean posttransplant time was 73.7±49.6 months. The results of DSCTCS were compared with ICA. RESULTS: In 100 patients (85 men; 15 women; mean age: 51.5±12.3 years), coronary calcifications were detected, and in 61 patients (45 men; 16 women; mean age: 49.0±11.7 years), coronary calcifications were excluded. ICA excluded CAV in 82 patients (63 men; 19 women; mean age: 48.6±11.9 years). In 79 patients (67 men; 12 women; mean age: 52.5±12.2 years), CAV was detected of whom 11 patients needed stent implantation. No statistically significant difference of DSCTCS in patients without (17.2±29.5; range: 0-190) and with CAV (33.4±66.8; range: 0-385) was observed (P=0.133). Moreover, 4 of 11 (36.4%) severely diseased patients had a calcium score of zero. Sensitivity, specificity, negative predictive value, and positive predictive value for CAV detection (calcium score threshold >0) was calculated as 72.2%, 47.6%, 47.7%, and 57.0%, respectively. Diagnostic accuracy was 59.6%. CONCLUSION: DSCTCS is not a valuable noninvasive modality for CAV detection and thus not recommended in clinical practice. Moreover, we hypothesize that it represents preexisting or de novo traditional coronary atherosclerosis than CAV.

Safety, efficacy, and indications of beta-adrenergic receptor blockade to reduce heart rate prior to coronary CT angiography.

For selected indications, coronary computed tomographic (CT) angiography is an established clinical technology for evaluation in patients suspected of having or known to have coronary artery disease. In coronary CT angiography, image quality is highly dependent on heart rate, with heart rate reduction to less than 60 beats per minute being important for both image quality and radiation dose reduction, especially when single-source CT scanners are used. ß-Blockers are the first-line option for short-term reduction of heart rate prior to coronary CT angiography. In recent years, multiple ß-blocker administration protocols with oral and/or intravenous application have been proposed. This review article provides an overview of the indications, efficacy, and safety of ß-blockade protocols prior to coronary CT angiography with respect to different scanner techniques. Moreover, implications for radiation exposure and left ventricular function analysis are discussed.

Pericardial adipose tissue determined by dual source CT is a risk factor for coronary atherosclerosis.

OBJECTIVES: Pericardial fat as a visceral fat depot may be involved in the pathogenesis of coronary atherosclerosis. To gain evidence for that concept we sought to investigate the relation of pericardial fat volumes to risk factors, serum adiponectin levels, inflammatory biomarkers, and the quantity and morphology of coronary atherosclerosis. METHODS AND RESULTS: Using Dual source CT angiography pericardial fat volume and coronary atherosclerosis were assessed simultaneously. Plaques were classified as calcified, mixed, and noncalcified, and the number of affected segments served as quantitative score. Patients with atherosclerotic lesions had significant larger PAT volumes (226 cm3+/-92 cm3) than patients without atherosclerosis (134 cm3+/-56 cm3; P>0.001). No association was found between BMI and coronary atherosclerosis. PAT volumes >300 cm3 were the strongest independent risk factor for coronary atherosclerosis (odds ratio 4.1; CI 3.63 to 4.33) also significantly stronger compared to the Framingham score. We furthermore demonstrated that elevated PAT volumes are significantly associated with low adiponectin levels, low HDL levels, elevated TNF-alpha levels, and hsCRP. CONCLUSION: In the present study we demonstrated that elevated PAT volumes are associated with coronary atherosclerosis, hypoadiponectinemia, and inflammation and represent the strongest risk factor for the presence of atherosclerosis and may be important for risk stratification and monitoring.

Detection of significant coronary artery stenosis with 64-slice computed tomography in heart transplant recipients: a comparative study with conventional coronary angiography.

PURPOSE: The present study evaluates clinical feasibility of cardiac multidetector computed tomography angiography (MDCTA) to detect significant stenosis of coronary vessels due to transplant vasculopathy (TVP) after heart transplantation (HTx). METHODS: Twenty-eight consecutive male HTx-recipients scheduled for their annual routine conventional coronary angiography (CCA) additionally underwent 64-slice MDCTA. RESULTS: Two patients were excluded from further MDCTA analysis. Out of 371 remaining coronary vessel segments evaluable by CCA, MDCTA was able to depict 302 (81.4%) in diagnostic image quality. On a segment based analysis, sensitivity, specificity, diagnostic accuracy (DA), negative predictive value (NPV), and positive predictive value (PPV) for detection of significant stenosis were calculated with 87.5%, 97.3%, 97.0%, 99.7%, and 46.7%, respectively. On a patient-based evaluation, sensitivity, specificity, DA, NPV, PPV were 100%, 81%, 84.6%, 100% and 55.6%, respectively. Evaluation of stenosis degree by MDCTA showed systematic overestimation of 4.4%. A moderate to good agreement comparing both modalities was found (Pearson's correlation coefficient: 0.64). CONCLUSION: High NPV suggesting 64-slice MDCTA being a reliable diagnostic tool for ruling out significant stenosis due to TVP in HTx patients. But its clinical value in these particular patients needs further investigation.

Predictive value of coronary calcifications for future cardiac events in asymptomatic patients with diabetes mellitus: a prospective study in 716 patients over 8 years.

BACKGROUND: To establish an efficient prophylaxis of coronary artery disease reliable risk stratification is crucial, especially in the high risk population of patients suffering from diabetes mellitus. This prospective study determined the predictive value of coronary calcifications for future cardiovascular events in asymptomatic patients with diabetes mellitus. METHODS: We included 716 patients suffering from diabetes mellitus (430 men, 286 women, age 55.2+/-15.2 years) in this study. On study entry all patients were asymptomatic and had no history of coronary artery disease. In addition, all patients showed no signs of coronary artery disease in ECG, stress ECG or echocardiography. Coronary calcifications were determined with the Imatron C 150 XP electron beam computed tomograph. For quantification of coronary calcifications we calculated the Agatston score. After a mean observation period of 8.1+/-1.1 years patients were contacted and the event rate of cardiac death (CD) and myocardial infarction (MI) was determined. RESULTS: During the observation period 40 patients suffered from MI, 36 patients died from acute CD. The initial Agatston score in patients that suffered from MI or died from CD (475+/-208) was significantly higher compared to those without cardiac events (236+/-199, p<0.01). An Agatston score above 400 was associated with a significantly higher annualised event rate for cardiovascular events (5.6% versus 0.7%, p<0.01). No cardiac events were observed in patients with exclusion of coronary calcifications. Compared to the Framingham risk score and the UKPDS score the Agatston score showed a significantly higher diagnostic accuracy in the prediction of MI with an area under the ROC curve of 0.77 versus 0.68, and 0.71, respectively, p<0.01. CONCLUSION: By determination of coronary calcifications patients at risk for future MI and CD could be identified within an asymptomatic high risk group of patients suffering from diabetes mellitus. On the other hand future events could be excluded in patients without coronary calcifications.

Cardiovascular events during World Cup soccer.

BACKGROUND: The Fédération Internationale de Football Association (FIFA) World Cup, held in Germany from June 9 to July 9, 2006, provided an opportunity to examine the relation between emotional stress and the incidence of cardiovascular events. METHODS: Cardiovascular events occurring in patients in the greater Munich area were prospectively assessed by emergency physicians during the World Cup. We compared those events with events that occurred during the control period: May 1 to June 8 and July 10 to July 31, 2006, and May 1 to July 31 in 2003 and 2005. RESULTS: Acute cardiovascular events were assessed in 4279 patients. On days of matches involving the German team, the incidence of cardiac emergencies was 2.66 times that during the control period (95% confidence interval [CI], 2.33 to 3.04; P<0.001); for men, the incidence was 3.26 times that during the control period (95% CI, 2.78 to 3.84; P<0.001), and for women, it was 1.82 times that during the control period (95% CI, 1.44 to 2.31; P<0.001). Among patients with coronary events on days when the German team played, the proportion with known coronary heart disease was 47.0%, as compared with 29.1% of patients with events during the control period. On those days, the highest average incidence of events was observed during the first 2 hours after the beginning of each match. A subanalysis of serious events during that period, as compared with the control period, showed an increase in the incidence of myocardial infarction with ST-segment elevation by a factor of 2.49 (95% CI, 1.47 to 4.23), of myocardial infarction without ST-segment elevation or unstable angina by a factor of 2.61 (95% CI, 2.22 to 3.08), and of cardiac arrhythmia causing major symptoms by a factor of 3.07 (95% CI, 2.32 to 4.06) (P<0.001 for all comparisons). CONCLUSIONS: Viewing a stressful soccer match more than doubles the risk of an acute cardiovascular event. In view of this excess risk, particularly in men with known coronary heart disease, preventive measures are urgently needed.

Predictive value of coronary calcifications for future cardiac events in asymptomatic individuals.

BACKGROUND: Reliable risk stratification is crucial for efficient prevention of coronary artery disease. The following prospective study determined the predictive value of coronary calcifications for future cardiovascular events. METHODS: We included 1726 asymptomatic individuals (1018 men, 708 women, age 57.7 +/- 13.3 years) referred for a cardiological examination. Coronary calcifications were determined with the Imatron C 150 XP electron beam computed tomography scanner. For quantification of coronary calcifications, we calculated the Agatston score. Over a mean observation period of 40.3 +/- 7.3 months we registered the event rate for cardiac death (CD) and myocardial infarction (MI). RESULTS: The Agatston score in patients who died of CD (n = 65) or had an MI (n = 114) was significantly higher compared with those without cardiac events (458 +/- 228 vs 206 +/- 201, P < .01). An Agatston score above the 75th percentile was associated with a significantly higher annualized event rate for MI (3.6% vs 1.6%, P < .05) and for CD (2.2% vs 0.9%) compared with patients with scores below the 75th percentile. No cardiac events were observed in patients where coronary calcifications could be excluded. CONCLUSIONS: By determination of coronary calcifications, patients at risk for future MI and CD could be identified within an asymptomatic population independent of concomitant risk factors. At the same time, future cardiovascular events could be excluded in patients without coronary calcifications.

Characteristics of coronary plaques before angiographic progression determined by Multi-Slice CT.

The aim of the present study was to characterize coronary plaques by Multi-Slice Computed Tomography (Siemens sensation 16, Forcheim, Germany) before significant angiographic progression occurred and to compare them to non-progressing lesions. The MSCT-morphology of coronary plaques leading to a rapid angiographic disease progression is not yet studied. In a series of 68 patients who were scheduled for surveillance angiography 6 months later, MSCT-angiography was done shortly after the baseline catheterisation-procedure. After surveillance angiography rapid progressive lesions with an increase of the stenosis severity of >20% were identified and analysed on the baseline MSCT-scan and were compared to non-progressing lesions. Six months after coronary stenting we observed significant progression of de novo stenoses in 10/438 coronary segments. The progression of four lesions lead to angina pectoris symptoms and the remaining six lesions progressed silently. Analysis of the lesion morphology by MSCT revealed that 5/10 (50%) progressing lesions were non-calcified 3/10 (30%) were predominantly non-calcified and 2/10 (20%) were mainly calcified on the baseline MSCT-scan. In the 428 segments without disease progression atherosclerotic lesions were found in 225 segments on MSCT. Non-calcified plaques were identified in 46 (20%), predominantly non-calcified lesions in 58 (26%) and predominantly calcified lesions in 121 (54%) segments. The average number of diseased coronary segments between patients with and without lesion progression was not significantly different between progressors and non-progressors with a higher prevalence of non-calcified segments in the progressor group (1.1 vs. 0.63). Rapid progression of the angiographic stenosis severity during a 6 months period occurs most frequently in coronary segments revealing non-calcified or predominantly non-calcified plaques as determined by MSCT, whereas lesion progression is rare in predominantly calcified segments. This represents first evidence that non-calcified lesions may be involved in the process of plaque rupture.

Diagnostic accuracy of dual-source computed tomography in the diagnosis of coronary artery disease.

PURPOSE: The aim of this study was to evaluate the diagnostic accuracy of dual-source computed tomography (DSCT) with reference to invasive coronary angiography in the diagnosis of coronary artery disease (CAD) on a per-patient as well as on a per-segment basis. MATERIALS AND METHODS: Thirty-five patients with known or suspected CAD underwent both DSCT (Somatom Definition, Siemens Medical Solutions) and quantitative x-ray coronary angiography (QCA). Parameters of CT acquisition were gantry rotation time 0.330 seconds (ie, temporal resolution 83 milliseconds), tube voltage 120 kV, tube current 560 mA with ECG-triggered tube current modulation and full current at 70% of the cardiac cycle for heart rates below 70 beats per minute or full current between 30% and 80% for higher and arrhythmic heart rates. The pitch was also adapted to the heart rate, ranging from 0.2 to 0.43. Volume and flow rate of contrast material (Ultravist 370, Schering AG) were adapted to the patient's body weight. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of DSCT in the detection or exclusion of significant CAD (ie, stenoses >50%) were evaluated on a per-patient and per-segment basis. RESULTS: All 35 CT angiograms were of diagnostic image quality. QCA demonstrated significant CAD in 48% (n = 17) and nonsignificant disease or normal coronary angiograms in 52% (n = 18) of the patients. Sensitivity, specificity, PPV, and NPV of DSCT on a per-patient basis were 100%, 89%, 89%, and 100%, respectively. On a per-segment basis, 473 of 481 coronary artery segments were assessable (98%). QCA demonstrated stenoses >50% in 32 segments (7%), and no disease or nonsignificant disease in 433 segments (93%). For the detection of stenoses >50% on a per-segment basis, DSCT showed a sensitivity, specificity, PPV, and NPV of 88%, 98%, 78%, and 99%, respectively. CONCLUSIONS: The comparison of coronary DSCT with QCA shows a very robust image quality and a high diagnostic accuracy in a patient-based as well as a per-segment analysis. Maximal sensitivity and NPV in the per-patient analysis show the strength of the technique in ruling out significant CAD.

Combined functional and morphological imaging consisting of gated myocardial perfusion SPECT and 16-detector multislice spiral CT angiography in the noninvasive evaluation of coronary artery disease: first experiences.

INTRODUCTION: Appropriate diagnosis and therapy of coronary artery disease (CAD) frequently require information about both the functional and morphological status of the coronary artery tree. We hypothesized that the combination of multislice spiral CT (MDCT) angiography and myocardial perfusion SPECT (MPI) provides accurate allocation of perfusion defects (PD) to their determining coronary lesion. METHODS: Twenty patients (14 male, mean age 64+/-9.2 years) with known CAD were retrospectively studied. Gated MPI, CT angiography using a 16-detector CT scanner, and conventional coronary angiography (CCA) were performed in each patient. Reversible and fixed PD were subsequently allocated to their determining lesion separately by different observers for MDCT angiography and CCA. RESULTS: All patients showed significant CAD in CCA; six patients with one-, six with two-, six with three-, and two with four-vessel disease; three patients had bypass grafts; and five patients had prior myocardial infarction. Correct diagnosis of CAD was stated in 14 of 20 patients by MDCT angiography. Five reversible and five fixed PD were detected in 9 of 20 patients; one patient showed both reversible and fixed PD. Five of five reversible PD could be allocated to appropriate coronary artery stenoses in CCA. In MDCT angiography, five of five reversible PD were allocated to the same lesions; all lesions were rated as >/=50%. CONCLUSIONS: The preliminary results of the present study show high accuracy for multislice spiral CT angiography to allocate reversible perfusion defects in myocardial scintigraphy to their determining coronary artery lesions in a small patient collective with known coronary artery disease.

[Prevention of coronary artery disease. Role of noninvasive imaging]. / Prävention der koronaren Herzerkrankung. Stellenwert bildgebender Verfahren.

Atherosclerosis and its complications are currently the most deadly and disabling diseases in affluent countries. Many individuals, even those with severe atherosclerosis, are unaware of their risk, because they have no symptoms. In 30-50% of patients, an acute heart attack is the first indicator of atherosclerosis. Risk stratification based on traditional risk factors (e.g., Framingham, PROCAM, ESC Scores) may identify persons at low and very high risk of heart attack or stroke within the next 10 years, but the majority of the population belongs to an intermediate-risk group. In this subgroup of individuals, the determination of coronary calcium adds independent prognostic information. With higher calcium scores the cardiovascular event rates increased substantially (five- to tenfold). The fact that coronary calcium affords incremental risk prognostication has led to the implementation of this method in international guidelines. The combination with myocardial perfusion scintigraphy also allows a cost-effective risk stratification in uncomplicated type 2 diabetes and in subjects with very high calcium scores (> 1,000). Plaque imaging with contrast-enhanced multislice spiral computed tomography is promising but is still not incorporated in the daily clinical routine. At present, magnetic resonance imaging is a promising research tool but is not yet appropriate in identifying subjects with high risk for coronary artery disease.

Diagnostic accuracy of dual-source multi-slice CT-coronary angiography in patients with an intermediate pretest likelihood for coronary artery disease.

AIMS: The aim of the present study was to assess the clinical performance of a dual X-ray source multi-slice CT (MSCT) with high temporal resolution to assess the coronary status in patients with an intermediate pretest likelihood for significant coronary artery disease (CAD) without using negative chronotropic pretreatment. METHODS AND RESULTS: Dual-source CT (DSCT) angiography (Siemens Definition) was performed in 90 patients with an intermediate likelihood for CAD who were referred for invasive coronary angiography. DSCT generated data sets with diagnostic image quality in 88 of the overall 90 patients. In six of seven patients with atrial fibrillation and in 46 of 48 patients with heart rates (HR)>65 b.p.m. image quality was diagnostic. In 20 of 21 patients with at least one stenosis>50% (sensitivity 95%) were correctly identified by DSCT-angiography. In 60 of 67 patients, a lesion>50% was correctly excluded (specificity 90%; positive predictive value 74%). The accuracy to detect patients with coronary stenoses>50% (sensitivity 92 vs. 100%; specificity 88 vs. 91%) was not significantly different among patients with HR>65 b.p.m. (n=46) and <65 b.p.m. The concordance of DSCT-derived stenosis quantification showed good correlation (r=0.76; P<0.001) to quantitative coronary angiography with a slight trend to overestimate the stenosis degree. CONCLUSION: DSCT is a non-invasive tool that allows to accurately rule out coronary stenoses in patients with an intermediate pretest likelihood for CAD, independent of the HR.

Low-dose tacrolimus/sirolimus and steroid withdrawal in heart recipients is highly efficacious.

Heart transplant recipients treated with long-term calcineurin inhibitors (CNIs) experience significant nephrotoxicity and transplant vasculopathy. Signal proliferation inhibitors might prevent the development of transplant vasculopathy. In an open, prospective pilot study, 33 primary heart transplant recipients received tacrolimus (Tac) and sirolimus (rapamycin, Rapa) with steroids. To reduce both nephrotoxicity and transplant vasculopathy at the same time, both Tac and Rapa exposure was kept low (6 to 8 ng/ml). Steroids were withdrawn successfully from all patients within 6 months. Just one acute rejection occurred at 54 days post-transplant, resulting in 0.03 acute rejection episode per patient at 1-year (primary end-point) and 2-year follow-up. Transplant vasculopathy assessed by angiogram was absent at 2 years. Graft and patient survival were 100% at 1 and 2 years. Accordingly, the survival estimate for freedom from first acute rejection, transplant vasculopathy, graft loss or death was 0.97 at 1 and 2 years. The regimen was well tolerated with only 3 patients requiring a change of study medication. Mean serum creatinine increased during the first year but returned to baseline at 2 years.

Optimization of contrast material administration for electrocardiogram-gated computed tomographic angiography of the chest.

OBJECTIVE: Electrocardiogram-gated computed tomographic angiography is increasingly used in the differential diagnosis of acute chest pain. We studied the optimal timing of contrast material injection using a test bolus and a bolus-tracking technique. MATERIALS AND METHODS: Thirty patients were prospectively included in the study. Volume and flow of high concentration contrast material were adapted to body weight. The scan delay was determined using either a test bolus or a bolus-tracking technique. Attenuation profiles of the different vascular districts were measured to evaluate the timing techniques. RESULTS: In all the patients except for one, an adequate and homogeneous contrast enhancement of more than 200 Hounsfield units (HU) was achieved (285 +/- 45 HU) in the different vascular districts. The pulmonary transit time in the test bolus group was 7 seconds (range, 4-11 seconds). Differences and variability of pulmonary and aortic enhancement were small in both groups (13 +/- 48 HU vs -9 +/- 21 HU), with differences of less than 70 HU over the craniocaudal range and very small intraindividual differences between pulmonary attenuation and systemic attenuation. CONCLUSIONS: Contrast administration regimens for electrocardiogramgated computed tomographic angiography of the chest can be optimized using the bolus-tracking method in the ascending aorta, with a short delay after trigger. Body weight adaptation of volume and injection rate of the contrast material results in a reliable simultaneous opacification of the pulmonary and systemic vasculature.

Comparison of progression of coronary calcium in postmenopausal women on versus not on estrogen/progestin therapy.

The prophylactic effect of postmenopausal hormone replacement therapy on coronary atherosclerosis remains controversial. We, therefore, examined the influence of combined estrogen/progestin therapy on the progression of coronary calcium as a marker of coronary atherosclerosis. We determined the extent of coronary calcium in 277 women (age 57 +/- 6 years, time after menopause 3.9 +/- 2.4 years, group I) at the beginning of hormone replacement therapy using multislice computed tomography. For quantification, we calculated the volume score. After an observation period of 3 years, we determined the progression of coronary calcium in a second scan. The results were compared with those from an age- and risk factor-adjusted group of postmenopausal women without hormone substitution (group II). No significant difference was found in the volume score (59 +/- 95 vs 58 +/- 88) or risk factor distribution between the 2 groups on study entry. In 56 women of group I and 52 women of group II, coronary calcium could be excluded on the initial scan (p = NS). After a mean observation time of 38.5 +/- 4.9 months, we observed no significant difference between the 2 groups regarding an increase in volume score (17 +/- 24 vs 19 +/- 27, p = NS) or the fraction of women with an increase in volume score (82.2% vs 84.2%). In conclusion, a reduced progression of coronary calcium in postmenopausal women on combined estrogen/progestin therapy could not be observed compared with a matched group of women without hormone substitution.

Sixty-four slice spiral CT angiography does not predict the functional relevance of coronary artery stenoses in patients with stable angina.

PURPOSE: The aim of this study was to evaluate spiral multidetector computed tomography (MDCT) angiography using 64-slice technique in the detection of functionally relevant coronary artery stenoses (CAS). METHODS: Thirty-eight patients (62+/-11 years, 28 men) with stable angina (26 with suspected and 12 with known coronary artery disease) were investigated using 64-slice MDCT angiography and gated myocardial perfusion SPECT (gated SPECT); a subgroup of 30 patients had additional invasive coronary angiography (ICA). Stenoses with luminal narrowing of >or=50% were defined as "significant" in MDCT angiography and ICA. MDCT angiography was compared with gated SPECT and the combination of gated SPECT plus ICA with respect to the detection of functionally relevant CAS. RESULTS: The sensitivity, specificity and negative and positive predictive values of MDCT angiography in detecting reversible perfusion defects on gated SPECT were 63%, 80%, 94% and 32%, respectively, in vessel-based analysis and 71%, 62%, 72% and 60%, respectively, in patient-based analysis. If only reversible perfusion defects on gated SPECT with CAS >or=50% on ICA were considered, the sensitivity, specificity and negative and positive predictive values were, respectively, 85%, 79%, 98% and 33% for vessel-based analysis and 85%, 59%, 83% and 61% for patient-based analysis. CONCLUSION: Sixty-four slice MDCT angiography failed to predict the functional relevance of CAS, but had a high negative predictive value in the exclusion of functionally relevant CAS in symptomatic patients.

Multislice computed tomography for determination of coronary artery disease in a symptomatic patient population.

BACKGROUND: Multislice computed tomography (MSCT) has started to replace Electron beam CT for quantitation of coronary artery calcium. However no study has evaluated the diagnostic accuracy of MSCT for prediction of coronary artery disease (CAD) in a symptomatic patient population using the volume score. METHODS AND RESULTS: 1347 symptomatic subjects (male = 803, mean age = 62 years) with suspected CAD underwent MSCT studies 1 +/- 2 days before the coronary angiogram. The Agatston (ACS) and Volumetric calcium score (VCS) were calculated using a proprietary workstation. Statistical analyses included the Pearson's correlation coefficient and the nonparametric Mann-Whitney U-test to compare the calcium score in different age groups and between men and women. Sensitivity, specificity and predictive accuracy were calculated for different calcium thresholds for prediction of CAD. ROC curve analyses were used to establish relations between the coronary calcium score and presence or absence of CAD. In 720 (53%) subjects (male = 419) angiography revealed a minimal lumen diameter stenosis greater than 50%. Patients with significant CAD had significantly higher total calcium score values than patients without CAD (P = 0.001). ACS and VCS demonstrate a close correlation for the whole study group, r = 0.99. The overall sensitivity of any calcium to predict stenosis was 99%, specificity = 32%. Exclusion of calcium was highly accurate for exclusion of CAD in subjects older than 50 years (predictive accuracy = 98%). An absolute cutoff >100 and an age and sex specific threshold (score over 75th percentile) were identified as the cutoff levels with the highest sensitivities (86-89%) and lowest false positive rates (20-22%). ROC analyses revealed MSCT calcium scanning as a good clinical test which can be performed with similar accuracy in all age groups with an area under the curve of 0.84. CONCLUSION: Determination of coronary calcium with MSCT is an accurate imaging modality for prediction of significant CAD in a patient population with intermediate likelihood of CAD. Exclusion of any calcium provided strong evidence that patients older than 50 years did not have obstructive CAD. ACS and VCS show an equivalent diagnostic accuracy.

ECG-gated 64-MDCT angiography in the differential diagnosis of acute chest pain.

OBJECTIVE: The most important differential diagnoses of acute chest pain include myocardial infarction, aortic dissection, and pulmonary embolism. The purpose of this study was to evaluate the diagnostic value of an ECG-gated 64-MDCT angiography protocol for simultaneous assessment of the pulmonary arteries, coronary arteries, and aorta within a single breath-hold. SUBJECTS AND METHODS: In 55 patients with acute chest pain, ECG-gated CT angiography was performed with a CT system in which 64 slices per gantry rotation were acquired. Density measurement and visual assessment of motion artifacts were performed to evaluate image quality. CT findings were correlated with results of laboratory tests and clinical follow-up. For 20 patients, two independent blinded reviewers compared findings on CT angiography with those on X-ray coronary angiography. RESULTS: Adequate contrast enhancement of the pulmonary vessels, coronary arteries, and aorta was achieved in all cases. Regarding image quality of the coronary arteries, there was minor blurring in seven patients, and in one examination the images did not provide enough information for diagnosis. The average image quality rating was 1.2 on a scale in which 1 indicated no artifacts; 2, minor motion artifacts; and 3, image insufficient for diagnosis. The cause of chest pain was correctly identified with MDCT in 37 patients. The diagnoses included pulmonary embolism (n = 10), coronary stenosis (n = 9), and aortic dissection (n = 1). In four patients, additional diagnoses were found with other examinations. CONCLUSION: With current techniques, ECG-gated CT angiography of the entire chest has very good image quality. The protocol proved helpful in the differential diagnosis of acute chest pain.

Visual and automatic grading of coronary artery stenoses with 64-slice CT angiography in reference to invasive angiography.

The aim of this study was to assess the performance of a software tool for quantitative coronary artery analysis of computed tomography coronary angiography (CT-QCA) in comparison with invasive coronary angiography with quantitative analysis (CAG-QCA) as standard of reference. Two radiologists reviewed the CT angiography data sets (Siemens Sensation 64) of 25 patients, grading coronary artery stenoses visually and with a software tool (Circulation, Siemens). Twenty-three data sets with sufficient image quality were included in the final analysis. CAG revealed a total of 30 wall irregularities and 28 stenoses, of which 17 were graded as moderate and nine as hemodynamically significant. CT-QCA showed a better agreement to CAG-QCA, with a systematic overestimation of the degree of stenosis of 6.1% and limits of agreement of +36.1% and -23.9; the correlation coefficient was 0.82 (p < 0.0001). Using CT-QCA, sensitivity, specificity, and positive and negative predictive value were 89%, 100%, 89%, and 100%, respectively, for significant area stenoses greater than 75%. The positive predictive value for the visual assessment amounted to 53%. Interobserver variability between CT-QCA and visual assessment showed a kappa value of 0.72. In conclusion, software-supported CT-QCA makes it possible to quantify significant coronary artery stenoses automatically, with good agreement to CAG-QCA.