Mitral valve reconstruction in a patient with Libman-Sacks endocarditis: a case report.

A symptomatic young woman with newly diagnosed systemic lupus erythematosus and secondary antiphospholipid syndrome with elevated anticardiolipin antibodies presented with small nodules on both leaflets of the mitral valve and with a consecutive high-grade mitral regurgitation, as diagnosed by echocardiography. In consideration of the preoperative and intraoperative findings, and the patient's low age, a mitral valve repair with removal of the leaflet vegetations and a ring annuloplasty were performed.

Characterization of non-calcified coronary atherosclerotic plaque by multi-detector row CT: comparison to IVUS.

UNLABELLED: Multi-detector row Computed Tomography (MDCT) permits non-invasive visualization of the coronary arteries. The ability to visualize and, with limitations, to characterize non-calcified coronary atherosclerotic plaque has been described. We investigated the CT attenuation of non-calcified plaques as determined by 16-slice MDCT in comparison to intravascular ultrasound (IVUS). METHODS AND RESULTS: Thirty-two patients were investigated by contrast-enhanced 16-slice CT. In addition, IVUS of one coronary artery (motorized pullback) was performed (LM+LAD: 22, LM+LCX: 4, RCA: 6). At 252 sites within the coronary system, in which non-calcified atherosclerotic plaque could be identified both in MDCT and IVUS, the CT attenuation within the plaque was measured using a centrally placed region of interest and correlated to the appearance of the plaque in IVUS at the corresponding location. The mean CT attenuation within plaque that corresponded to hyper-echogenic appearance in IVUS was 121+/-34HU (n=76). The mean CT attenuation within plaque that corresponded to hypo-echogenic appearance was 58+/-43HU (n=176, p<0.001). However, there was substantial overlap of the density values measured by MDCT in the two groups. CONCLUSIONS: A significant difference of the mean CT attenuation within atherosclerotic lesions of hypo-echogenic and hyper-echogenic appearance in IVUS could be observed. However, we observed substantial overlap of attenuation values between plaque types so that the differentiation of "vulnerable" and "stable" plaques based on their CT attenuation is doubtful.

Visualization of coronary artery anomalies by contrast-enhanced multi-detector row spiral computed tomography.

BACKGROUND: We investigated the potential of 16-slice multi-detector row spiral CT (MDCT) with retrospective ECG-gating for evaluation of coronary artery anomalies. METHODS: A total of 35 patients (23 men, 12 women, 19-81 years) in whom anomalous coronary arteries had been detected by invasive coronary angiography underwent MDCT (Sensation 16, Siemens, Germany). During one breathhold, a contrast-enhanced (90 ml, 5 ml/s) volume data set of the heart was acquired (16x0.75mm collimation, gantry rotation 375 ms). Images were reconstructed with a slice thickness of 1.0 mm in 0.5-mm intervals using retrospective ECG-gated reconstruction. The 35 data sets and 80 data sets of patients with angiographically normal coronary anatomy were analysed in random order concerning the origin and course of the coronary arteries. The results were compared to invasive coronary angiography. RESULTS: All patients with coronary artery anomalies and all controls with normal coronary anatomy were identified by MDCT. In addition, the origins and course concerning their anatomical relationship to adjacent cardiac structures were visualized in all patients, including right-sided origin of the left main (n=10), left anterior descending coronary artery (n=4) or left circumflex coronary artery (n=10); left-sided origin of the right coronary artery (n=6); four coronary fistula to the pulmonary artery (two from the left anterior descending, one from the right coronary artery, one from the left main), and one fistula from the circumflex coronary artery to the left atrium CONCLUSIONS: The study demonstrates that MDCT is a reliable noninvasive technique to identify and define anomalous coronary arteries and their course.

Analysis of coronary calcifications versus Framingham and PROCAM risk assessment in patients with a first myocardial infarction.

UNLABELLED: We compared the extent of coronary calcifications as quantified by electron beam tomography (EBT) to the predicted 10-year cardiovascular event risk based on Framingham and PROCAM algorithms in patients with a first myocardial infarction (MI). METHODS: In 156 patients (56.7 +/- 22 years), EBT was performed <4 weeks after MI. Coronary calcifications were quantified using the "Agatston Score" and age-related calcium percentiles were determined. The predicted 10-year event risk was determined using Framingham and PROCAM algorithms. RESULTS: Coronary calcifications were present in 148 patients with a mean "Agatston Score" of 589.2 +/- 976. The "Agatston Score" was >400 in 44% and >90th percentile in 42% of the patients. Framingham risk was >20% in 32% and PROCAM risk was >20% in 28%. CONCLUSION: Coronary calcifications were detected in the vast majority of patients with a first MI, independent from the patient's age. The determination of age-related percentiles was superior to the Framingham or PROCAM algorithm.

Coronary artery bypass graft (CABG) patency: assessment with high-resolution submillimeter 16-slice multidetector-row computed tomography (MDCT) versus coronary angiography.

PURPOSE: To investigate the ability of 16-slice multidetector-row computed tomography (MDCT) to visualize coronary artery bypass graft (CABG) patency and to detect bypass stenoses. MATERIALS AND METHODS: Thirty-two patients with 94 grafts (20 mammary artery grafts, 74 venous grafts) were investigated by 16-slice MDCT using a scan protocol with 12 x 0.75 mm slice collimation (pitch 0.3), 420 ms rotation time and simultaneous electrocardiogram (ECG)-registration. One hundred milliliters iodinated contrast agent were injected with a delay according to the individually determined contrast agent transit time. Patients with heart rates above 60 bpm received oral beta-blockade. Cross-sectional images with a slice width of 1.0 mm (0.5 mm increment) were reconstructed using an ECG-gated half-scan reconstruction or a multisegment reconstruction algorithm depending on the heart rate. Bypass grafts were evaluated concerning patency and presence of stenoses > or = 50% diameter reduction on cross-sectional images, multiplanar reformations and maximum intensity projections by two independent observers. Results were compared to coronary bypass angiography. RESULTS: Sixteen-slice MDCT results were compared to those of invasive coronary angiography concerning absence or presence of bypass graft occlusion or relevant stenosis > or = 50% lumen reduction. Coronary CT angiography (CTA) permitted detection of bypass occlusion with 100% sensitivity (28/28) and 98% specificity (64/65). Seventy-eight percent (observer 1) and 84% (observer 2) of all patent grafts were found to be evaluable concerning presence or absence of stenosis. In 34 of 40 (observer 1) and 38 of 43 (observer 2) bypass grafts, high-grade stenoses were correctly ruled out (specificity 85% versus 88%, sensitivity 80% and 82%). Yet, if all patients with either unevaluable grafts/graft anastomosis or relevant graft stenosis were excluded, only 8/32 patients (25%) had fully diagnostic "negative" graft-CTA. According to Kappa statistics, agreement between the observers was 1.0 and 0.93 concerning occlusion and relevant stenosis, respectively. CONCLUSION: Sixteen-slice coronary CTA with sub-millimeter spatial resolution and premedication with oral beta-blockade permits non-invasive assessment of coronary artery bypass grafts with decreasing numbers of unevaluable graft segments. However, patient-based analysis reveals that only a relatively small number of patients ("negative" and completely evaluable graft-CTA) truly profits from noninvasive work-up and could be spared invasive angiography.

Detection of coronary artery stenoses with thin-slice multi-detector row spiral computed tomography and multiplanar reconstruction.

BACKGROUND: We analyzed the accuracy of multi-detector row spiral computed tomography (MDCT) using a 16-slice CT scanner with improved spatial and temporal resolution, as well as routine premedication with beta-blockers for detection of coronary stenoses. METHODS AND RESULTS: Seventy-seven patients with suspected coronary disease were studied by MDCT (12x0.75-mm cross-sections, 420 ms rotation, 100 mL contrast agent IV at 5 mL/s). Patients with a heart rate above 60/min received 50 mg atenolol before the scan. In axial MDCT images and multiplanar reconstructions, all coronary arteries and side branches with a diameter of 1.5 mm or more were assessed for the presence of stenoses exceeding 50% diameter reduction. In comparison to invasive coronary angiography, MDCT correctly classified 35 of 41 patients (85%) as having at least 1 coronary stenosis and correctly detected 57 of 78 coronary lesions (73%). After excluding 38 of 308 coronary arteries (left main, left anterior descending, left circumflex, and right coronary artery in 77 patients) classified as unevaluable by MDCT (12%), 57 of 62 lesions were detected, and absence of stenosis was correctly identified in 194 of 208 arteries (sensitivity: 92%; specificity: 93%; accuracy: 93%; positive and negative predictive values: 79% and 97%). CONCLUSIONS: MDCT coronary angiography with improved spatial resolution and premedication with oral beta-blockade permits detection of coronary artery stenoses with high accuracy and a low rate of unevaluable arteries.

Detection of calcified and noncalcified coronary atherosclerotic plaque by contrast-enhanced, submillimeter multidetector spiral computed tomography: a segment-based comparison with intravascular ultrasound.

BACKGROUND: We investigated the ability of multidetector spiral computed tomography (MDCT) to detect atherosclerotic plaque in nonstenotic coronary arteries. METHODS AND RESULTS: In 22 patients without significant coronary stenoses, contrast-enhanced MDCT (0.75-mm collimation, 420-ms rotation) and intravascular ultrasound (IVUS) of one coronary artery were performed. A total of 83 coronary segments were imaged by IVUS (left main, 19; left anterior descending, 51; left circumflex, 4; right coronary, 9). MDCT data sets were evaluated for the presence and volume of plaque in the coronary artery segments. Results were compared with IVUS in a blinded fashion. For the detection of segments with any plaque, MDCT had a sensitivity of 82% (41 of 50) and specificity of 88% (29 of 33). For calcified plaque, sensitivity was 94% (33 of 36) and specificity 94% (45 of 47). Coronary segments containing noncalcified plaque were detected with a sensitivity of 78% (35 of 45) and specificity of 87% (33 of 38), but presence of exclusively noncalcified plaque was detected with only 53% sensitivity (8 of 15). If analysis was limited to the 41 proximal segments (segments 1, 5, 6, and 11 according to American Heart Association classification), sensitivity and specificity were 92% and 88% for any plaque, 95% and 91% for calcified plaque, and 91% and 89% for noncalcified plaque. MDCT substantially underestimated plaque volume per segment as compared with IVUS (24+/-35 mm3 versus 43+/-60 mm3, P<0.001). CONCLUSIONS: The results indicate the potential of MDCT to detect coronary atherosclerotic plaque in patients without significant coronary stenoses. However, further improvements in image quality will be necessary to achieve reliable assessment, especially of noncalcified plaque throughout the coronary tree.

Influence of lipid-lowering therapy on the progression of coronary artery calcification: a prospective evaluation.

BACKGROUND: Coronary calcification measured by fast computed tomography techniques is a surrogate marker of coronary atherosclerotic plaque burden. In a cohort study, we prospectively investigated whether lipid-lowering therapy with a cholesterol synthesis enzyme inhibitor reduces the progression of coronary calcification. METHODS AND RESULTS: In 66 patients with coronary calcifications in electron beam tomography (EBT), LDL cholesterol >130 mg/dL, and no lipid-lowering treatment, the EBT scan was repeated after a mean interval of 14 months and treatment with cerivastatin was initiated (0.3 mg/d). After 12 months of treatment, a third EBT scan was performed. Coronary calcifications were quantified using a volumetric score. Cerivastatin therapy lowered the mean LDL cholesterol level from 164+/-30 to 107+/-21 mg/dL. The median calcified volume was 155 mm3 (range, 15 to 1849) at baseline, 201 mm3 (19 to 2486) after 14 months without treatment, and 203 mm3 (15 to 2569) after 12 months of cerivastatin treatment. The median annualized absolute increase in coronary calcium was 25 mm3 during the untreated versus 11 mm3 during the treatment period (P=0.01). The median annual relative increase in coronary calcium was 25% during the untreated versus 8.8% during the treatment period (P<0.0001). In 32 patients with an LDL cholesterol level <100 mg/dL under treatment, the median relative change was 27% during the untreated versus -3.4% during the treatment period (P=0.0001). CONCLUSIONS: Treatment with the cholesterol synthesis enzyme inhibitor cerivastatin significantly reduces coronary calcium progression in patients with LDL cholesterol >130 mg/dL.

Assessment of coronary remodeling in stenotic and nonstenotic coronary atherosclerotic lesions by multidetector spiral computed tomography.

OBJECTIVES: This study was designed to investigate whether contrast-enhanced multidetector spiral CT (MDCT) permits assessment of remodeling in coronary atherosclerotic lesions. BACKGROUND: With sufficient image quality, MDCT permits noninvasive visualization of the coronary arteries, but its ability to assess remodeling has not been evaluated. METHODS: Out of 102 patients in whom MDCT (16-slice scanner, intravenous contrast, 0.75-mm collimation, 420 ms rotation) was performed before invasive coronary angiography, 44 patients with high-quality MDCT data sets showing atherosclerotic plaque in a proximal coronary artery segment were chosen for evaluation. In multiplanar reconstructions orthogonal to the coronary artery, the cross-sectional vessel area was measured for the respective lesion and for a reference segment proximal to the lesion. The "Remodeling Index" was calculated by dividing the vessel area in the lesion by the reference segment. Results were correlated to the presence of stenosis (>50% diameter reduction) in invasive angiography. In a subset of 13 patients, MDCT measurements were verified by IVUS. RESULTS: Reference vessel area was not significantly different between nonstenotic versus stenotic lesions (20 +/- 8 mm(2), n = 23 vs. 22 +/- 8 mm(2), n = 21). The mean Remodeling Index was significantly higher in nonstenotic than in stenotic lesions (1.3 +/- 0.2 vs. 1.0 +/- 0.2, p < 0.001). In five stenotic lesions, "negative remodeling" (Remodeling Index < or = 0.95) was observed. Cross-sectional vessel areas and Remodeling Indices measured by MDCT correlated closely to IVUS (r(2) = 0.77 and r(2) = 0.82, respectively). CONCLUSIONS: Multidetector spiral CT may permit assessment of remodeling of coronary atherosclerotic lesions in selected data sets of sufficient quality.

Relation between coronary calcium and 10-year risk scores in primary prevention patients.

In 380 patients, coronary calcifications were quantified by electron beam tomography and compared with the predicted 10-year cardiovascular event risk determined by the Framingham equation, Adult Treatment Panel III tables, and the PROCAM algorithm. The correlation between the amount of calcium and the predicted cardiac event risk was low (correlation coefficient range 0.19 to 0.28). The assessment of coronary calcium may thus potentially yield information that is additive to the analysis of traditional risk factors.

Comparison of measurement of cross-sectional coronary atherosclerotic plaque and vessel areas by 16-slice multidetector computed tomography versus intravascular ultrasound.

In 26 patients, 16-slice multidetector computed tomography (MDCT) with 0.75-mm collimation and intravascular ultrasound (IVUS) of 1 coronary artery were performed. At 100 sites within the coronary arteries, the measurement of cross-sectional luminal area and, if detectable, the cross-sectional area of atherosclerotic plaque was performed independently with IVUS and MDCT. The mean luminal area (r = 0.92), measured at 100 sites, and plaque area (r = 0.55), measured at 65 sites, were significantly correlated (p <0.001) between MDCT and IVUS. The mean luminal area and mean plaque area were slightly but significantly overestimated with MDCT. MDCT permits the noninvasive measurement of coronary cross-sectional luminal and plaque areas with moderate accuracy.

Association of cardiovascular risk factors to aortic valve calcification as quantified by electron beam computed tomography.

OBJECTIVE: To analyze the association among aortic valve calcification, cardiovascular risk factors, and coronary artery calcification using electron beam computed tomography (EBCT). PATIENTS AND METHODS: We analyzed cardiac EBCT data obtained for coronary calcium detection in 1000 consecutively enrolled patients (mean +/- SD age, 57.1 +/- 10 years; 69% men) between January 1, 1998, and July 23, 2001. In all patients, atherosclerotic risk factors (hyperlipidemia, hypertension, diabetes, smoking, and family history of coronary artery disease) were documented. With EBCT, the amount of coronary calcification was determined using the Agatston score, and the amount of aortic valve calcification was measured using a volumetric score. RESULTS: Aortic valve calcification was detected in 177 (17.7%) of the total patient group and was found more frequently in patients with coronary calcification (20.5% in patients with coronary calcium vs 3.8% in patients without coronary calcium; P < .001), hyperlipidemia (19.5% vs 6.5%; P < .001), hypertension (21.7% vs 13.9%; P = .01), or diabetes (30.7% vs 16.6%; P = .002). The volume of aortic valve calcification was significantly higher in patients with vs without hyperlipidemia (P < .001), hypertension (P = .002), and diabetes (P = .001). In a multivariable logistic regression analysis, adjusted for age and sex, hyperlipidemia (P = .001) and the presence of coronary calcification (P < .001) were significant predictors of aortic valve calcification. CONCLUSION: A significant association exists among atherosclerotic risk factors, coronary calcification, and the presence and amount of aortic valve calcification.

Quantification of aortic valve calcification with electron beam tomography: a histomorphometric validation study.

RATIONALE AND OBJECTIVES: The exact quantification of the amount of calcification in aortic valves may be useful for the identification of risk factors for the progression of aortic valve calcification and to evaluate new therapeutic approaches for aortic valve disease. Electron beam tomography (EBT) allows the in vivo detection of calcifications in coronary vessels and in the aortic valve. The aim of this study was to validate the quantification of aortic valve calcification by EBT with in vivo and in vitro investigations. METHODS: In 15 patients (aortic stenosis in 13, aortic regurgitation in 2 cases), EBT was performed before aortic valve replacement (40 cross sections, 3-mm slice thickness, matrix 512 x 512, field of view 28 cm, ECG trigger at 40% of the cardiac cycle). EBT was repeated on the explanted aortic valve using the same protocol. In both data sets, the amount of aortic valve calcification was determined using a volumetric score. In serial cuts of the explanted valve (distance 1 mm), the calcified volume was determined by an independent investigator using histomorphometric analysis. RESULTS: The mean calcified volume of the aortic valves as quantified by EBT was 1650.0 +/- 1401.0 mml in vivo (EBT1) and 1544.4 +/- 1266.5 mml in vitro (EBT2). Histomorphometric analysis showed a mean calcified volume of 1555.7 +/- 1272.5 mml. The mean difference between EBT1 and EBT2 was 4.2 +/- 14.7%, between EBT1 and histomorphometry 3.6 +/- 12.1%, and between EBT2 and histomorphometry -0.5 +/- 5.9%. CONCLUSION: EBT allows accurate in vivo quantification of aortic valve calcifications.

Comparison of image quality in contrast-enhanced coronary-artery visualization by electron beam tomography and retrospectively electrocardiogram-gated multislice spiral computed tomography.

RATIONALE AND OBJECTIVES: To compare the image quality of electron beam tomography (EBT) and multislice spiral CT (MSCT) for coronary artery visualization. MATERIALS AND METHODS: Two groups of 30 patients without coronary stenoses were studied by MSCT (4 x 1 mm collimation) or EBT (3 mm slice thickness). Contrast-to-noise ratio (CNR), overall length of the visualized arteries and vessel length free of motion artifacts were measured. RESULTS: Length of visualized arteries was equal in MSCT and EBT. In EBT, longer segments were depicted free of motion artifacts (MSCT: 73%, EBT: 92% of visualized length, P< 0.001) and CNR was significantly higher than in MSCT (15.4 vs. 9.0; P< 0.001). In both modalities, vessel diameters correlated closely to quantitative coronary angiography. CONCLUSIONS: EBT and MSCT permit reliable coronary artery visualization and measurement of vessel diameters. For the used scan protocol, MSCT images had a lower CNR and were more frequently affected by motion.

Clinical results of minimally invasive coronary angiography using computed tomography.

Fast, high-resolution CT techniques, such as EBCT and MDCT permit imaging of the coronary arteries. Continuous improvements in the capabilities of both technologies for visualization of the coronary lumen and detection of coronary artery stenoses are being made. Image quality currently is not robust enough in all patients to consider non-invasive coronary angiography by EBCT and MDCT a routine clinical tool. In selected patients and carefully performed, however, they show promise as means to exclude the presence of coronary artery stenoses in a non-invasive fashion. This may become a beneficial and important application of these technologies. Other possible applications pertain to smaller patient subsets, such as patients with anomalous coronary arteries, fistulas or aneurysms. The development of techniques to visualize non-calcified plaque is interesting with respect to assessment of coronary risk, but this requires further investigation.