[Mechanical circulatory support systems : When and how much protection does a PCI need?] / Mechanische Kreislaufunterstützungssysteme : Wie viel Schutz braucht eine PCI wann?

The interventional treatment of high-risk patients remains challenging and has a high potential for improvement despite all technical innovations. Mechanical circulatory support (MCS) systems can be meaningful depending on the clinical situation, although a clear study situation for this is so far lacking. Multivessel coronary disease and a high SYNTAX score combined with impaired ventricular function is a possible predictor combination for the use of MCS that justifies the higher risk of complications.

Coronary CT angiography (CCTA) using third-generation dual-source CT for ruling out in-stent restenosis.

AIMS: Late in-stent restenosis (ISR) has become increasingly important, in particular due to neo-atherosclerosis. CCTA is a highly sensitive method for detecting coronary plaques. Its diagnostic accuracy regarding ISR is controversial. Stent artifacts can impede image quality, but recent developments in CT-technology may help to overcome some of these problems and allow for improved diagnostic accuracy. METHODS: Consecutive patients after previous coronary revascularization who had stable symptoms or signs of possible disease progression were examined using a third-generation dual-source CT scanner. After the scan, patients were followed for clinical events (MACE) over a mean of 399 days. Patients with high-grade stenoses were referred for invasive coronary angiography (ICA), unclear findings were further evaluated either by ICA or functional testing. RESULTS: Overall, 226 patients were included. A total of 457 stents were evaluated (2.0 ± 1.4 per patient). Mean stent diameter was 2.9 ± 0.45 mm. In 61%, a high-pitch protocol was employed. Mean dose-length product (DLP) of CCTA was 159.2 mGy cm, corresponding to 2.2 mSv using a conversion factor of k = 0.014. Mean amount of contrast agent was 58.3 ± 12.5 ml. In 145 patients (64%), CCTA was negative. In this group, one MACE occurred (acute coronary syndrome) during follow-up in a patient who had also undergone unremarkable ICA. In 23 patients (10%), CCTA detected 28 ISR which were confirmed and treated by ICA (true positive). In 27 patients (12%), ISR was suspected by CCTA but excluded by ICA (false positive), 30 patients (13%) had unclear findings and normal non-invasive tests. No MACE occurred during follow-up in these patients. One patient was misclassified in CCTA as having intermediate and not high-grade ISR who underwent revascularization within 3 months. Eleven patients (5%) were lost to follow-up. During follow-up, eight patients had myocardial infarctions due to five ISRs and three de novo lesions. No patient died. In cases with unclear or false-positive findings, the amount of stents was significantly higher, stents were smaller and patients had a higher BMI. CONCLUSION: In almost two-thirds of symptomatic patients with previous coronary stent implantation, ISR could be ruled out by CCTA. 10% of patients had definite ISR. The rate of false-negative findings was low (< 1%), whereas the rate of false positive or inconclusive findings was 25%, leading to invasive rule-out of ISR by ICA in 12%. CCTA appears valuable as a tool for safely excluding ISR. It might help to avoid invasive diagnostic procedures. Further analyses are warranted, in particular regarding the influence of stent dimensions and the total amount of stents in a patient.

[Imaging in structural heart disease : Impact on interventional therapy]. / Bildgebung bei struktureller Herzerkrankung : Bedeutung für die interventionelle Therapie.

For the treatment of structural heart disease, current options in the catheterization laboratory include MitraClip® implantation for treating severe mitral regurgitation, transcatheter aortic valve implantation (TAVI), closure of a patent foramen ovale (PFO) and occlusion of the left atrial appendage (LAA). These treatment options are based on a precise diagnosis provided by modern cardiac imaging, which is indispensable for treatment recommendations. Its importance for supporting the invasive procedures in the catheterization laboratory is less well known. Due to enhanced soft tissue characterization, it complements fluoroscopy and invasive angiography and thus enormously improves the safety of the procedures. In addition, it allows individualized follow-up care. The current article gives an overview of the clinically most frequently used procedures.

Gender and age effects on risk factor-based prediction of coronary artery calcium in symptomatic patients: A Euro-CCAD study.

BACKGROUND AND AIMS: The influence of gender and age on risk factor prediction of coronary artery calcification (CAC) in symptomatic patients is unclear. METHODS: From the European Calcific Coronary Artery Disease (EURO-CCAD) cohort, we retrospectively investigated 6309 symptomatic patients, 62% male, from Denmark, France, Germany, Italy, Spain and USA. All of them underwent risk factor assessment and CT scanning for CAC scoring. RESULTS: The prevalence of CAC among females was lower than among males in all age groups. Using multivariate logistic regression, age, dyslipidaemia, hypertension, diabetes and smoking were independently predictive of CAC presence in both genders. In addition to a progressive increase in CAC with age, the most important predictors of CAC presence were dyslipidaemia and diabetes (ß = 0.64 and 0.63, respectively) in males and diabetes (ß = 1.08) followed by smoking (ß = 0.68) in females; these same risk factors were also important in predicting increasing CAC scores. There was no difference in the predictive ability of diabetes, hypertension and dyslipidaemia in either gender for CAC presence in patients aged <50 and 50-70 years. However, in patients aged >70, only dyslipidaemia predicted CAC presence in males and only smoking and diabetes were predictive in females. CONCLUSIONS: In symptomatic patients, there are significant differences in the ability of conventional risk factors to predict CAC presence between genders and between patients aged <70 and ≥70, indicating the important role of age in predicting CAC presence.

The coronary calcium score is a more accurate predictor of significant coronary stenosis than conventional risk factors in symptomatic patients: Euro-CCAD study.

AIMS: In this retrospective study we assessed the predictive value of the coronary calcium score for significant (>50%) stenosis relative to conventional risk factors. METHODS AND RESULTS: We investigated 5515 symptomatic patients from Denmark, France, Germany, Italy, Spain and the USA. All had risk factor assessment, computed tomographic coronary angiogram (CTCA) or conventional angiography and a CT scan for coronary artery calcium (CAC) scoring. 1539 (27.9%) patients had significant stenosis, 5.5% of whom had zero CAC. In 5074 patients, multiple binary regression showed the most important predictor of significant stenosis to be male gender (B=1.07) followed by diabetes mellitus (B=0.70) smoking, hypercholesterolaemia, hypertension, family history of CAD and age but not obesity. When the log transformed CAC score was included, it became the most powerful predictor (B=1.25), followed by male gender (B=0.48), diabetes, smoking, family history and age but hypercholesterolaemia and hypertension lost significance. The CAC score is a more accurate predictor of >50% stenosis than risk factors regardless of the means of assessment of stenosis. The sensitivity of risk factors, CAC score and the combination for prediction of >50% stenosis when measured by conventional angiogram was considerably higher than when assessed by CTCA but the specificity was considerably higher when assessed by CTCA. The accuracy of CTCA for predicting >50% stenosis using the CAC score alone was higher (AUC=0.85) than using a combination of the CAC score and risk factors with conventional angiography (AUC=0.81). CONCLUSION: In symptomatic patients, the CAC score is a more accurate predictor of significant coronary stenosis than conventional risk factors.

[Hemoptysis as the first sign of ruptured thoracic aorta]. / Hämoptyse als erstes Anzeichen einer thorakalen Aortenruptur.

Acute aortic rupture is associated with a high mortality. The leading symptoms are chest pain, dyspnea and hemodynamic instability as well as hemoptysis. In the current case report a patient with known coronary artery disease and prior coronary artery bypass surgery presented with hemoptysis. He was initially treated for a presumed gastroenterological disorder. The chest X-ray delineated a structure suggestive of aortic rupture and this diagnosis was confirmed by computed tomography. Emergency treatment was performed by implantation of an endovascular stent prosthesis. This procedure is currently regarded the standard treatment of rupture of the descending thoracic aorta. We conclude our case report with a discussion of epidemiology, symptoms, pathogenesis and therapy of this clinically dramatic disease.

Concomitant atherosclerotic disease detected by whole-body MR angiography in relation to coronary artery calcification in patients with coronary artery disease.

PURPOSE: Patients with coronary artery disease (CAD) show a high prevalence for concomitant atherosclerotic peripheral arterial disease (PAD). On the other hand, PAD seems to be an additional risk factor for cardiac events. We evaluated the correlation between arterial pathologies as found in whole-body MR angiography and coronary artery calcification (CAC) detected by electron beam computed tomography (EBCT) and multislice CT (MSCT). MATERIALS AND METHODS: Two hundred and twenty-eight patients (161 men; 67 women) with suspicion for CAD/known CAD underwent whole-body contrast-enhanced MR angiography (wb-ce-MRA) and EBCT/MSCT. An atherosclerosis index was calculated for each patient Index = (40)Sigma(n=1) w(i) with w(i) being the grading of the stenosis of the i (ten) of 40 arteria segments (grade: 0 - no plaque; 1 - plaque - < or = 50 % stenosis; 2 - > 50 % stenosis - < or = 90 % stenosis; 3 - > 90 % stenosis - < 100 % stenosis; 4 - occlusion). Correlations between CAC and atherosclerosis index were performed. RESULTS: Wb-ce MRA and CAC correlate only moderately in this population. An atherosclerosis index 8 renders a positive predictive value for a CAC 100 of 63.3 %. CONCLUSION: An atherosclerosis index as defined in this study does not fully correlate with the extent of CAD as revealed by catheter angiography or EBCT/MSCT, but it might theoretically mirror the increased risk by PAD. It thus might be a promising complementary parameter for the prediction of cardiac events. Future studies need to show its possible additional predictive impact.

Radiation dose exposure of computed tomography coronary angiography: comparison of dual-source, 16-slice and 64-slice CT.

BACKGROUND: Dual-source CT (DSCT) promises a significant reduction of radiation dose exposure for coronary CT angiography (CTA). Large studies on radiation dose estimates are rare. OBJECTIVE: To compare radiation dose estimates of DSCT with 16- and 64-slice multidetector CT (MDCT) for non-invasive coronary angiography. PATIENTS AND DESIGN: Retrospective data analysis was performed on 292 patients: 56 patients were examined with 16-slice MDCT, 38 patients with 64-slice MDCT and 202 patients using DSCT. The effective dose (ED) estimates were calculated for all patients from the dose-length product and the conversion factor k (0.017 mSv/mGy/cm), as recommended by current guidelines. RESULTS: The mean (SD) ED for patients examined by 16-slice MDCT was 9.8 (1.8) mSv, for 64-slice MDCT 8.6 (2.8) mSv and for DSCT 11.4 (7.2) mSv. With a protocol of 100 kV tube voltage and 110 ms ECG pulsing window the mean (SD) ED was 3.8 (1.7) mSv for DSCT scanning. When DSCT with a tube voltage of 100 kV was used, a significant inverse correlation between heart rate and radiation dose exposure was found. CONCLUSIONS: When standard protocols for coronary CTA with 16-, 64-slice MDCT and DSCT scanners are used, the radiation dose is still high. However, using optimised and individually adjusted protocols low estimated radiation doses can be achieved.

Impact of disease duration on coronary calcification in patients with acromegaly.

It is well established, that the increased mortality in patients with acromegaly is due to cardiac diseases. Cardiomyopathy is the predominant cardiac alteration in patients with acromegaly. There are less data about coronary heart disease or coronary calcifications. Electron beam computed tomography (EBCT) is the standard imaging modality for identification of coronary artery calcifications (CAC) and can determine the extent and severity of coronary atherosclerosis. Coronary risk was evaluated by the Framingham risk score (FRS). The prospective study included 30 patients with acromegaly (mean age 53+/-14 year; 16 females, 14 males; BMI 28.1+/-3.6 kg/m (2); mean+/-SD), 12 patients had active disease (IGF-1 751+/-338 microg/L; GH 25.6+/-36.4 microg/L), 9 were well-controlled (IGF-1 157+/-58 microg/L; GH 1.8+/-1.1 microg/L) under somatostatin analogue octreotide (n=5), dopamine agonists (n=2), and the GH receptor antagonist pegvisomant (n=2; GH levels were not determined in this subgroup) and 9 were cured IGF-1 (148+/-57 microg/L; GH 0.5+/-0.2 microg/L). Increased left ventricular muscle mass index (LVMI >132 g/m (2)) was focused in 53%, hypercholesterinemia in 63%, hypertension in 43%, diabetes mellitus/impaired glucose tolerance in 27%, and smokers in 53% (pack per year 9+/-15 yr). For quantification of CAC the EBCT was used and the Agatston calcium score was determined. Results were composed to established age and sex adjusted percentile distribution of CAC. CAC was present in 53%, high CAC score (75 (th) percentile) in 37% and were categorized as cardiovascular high risk patients. FRS was related to the CAC score (p=0.008, r (2)=0.22) and the disease duration (p=0.002, r (2)=0.29). The CAC score correlated with LVMI (p=0.02, r (2)=0.17), the disease duration of acromegaly (p=0.004, r (2)=0.36), and the FRS (p=0.008, r (2)=0.22). Patients with a high CAC score had a longer disease duration of 9.6+/-4.7 versus 5.4+/-2.8 years with CAC<75 (th) percentile (p=0.02). In summary, the disease duration and consequently the accompanying metabolic disorders appear to influence the degree of CAC in patients with acromegaly. The observations underline the importance of early and sufficient treatment of acromegaly in high risk patients.

Association of impaired fasting glucose and coronary artery calcification as a marker of subclinical atherosclerosis in a population-based cohort--results of the Heinz Nixdorf Recall Study.

AIMS/HYPOTHESIS: Atherosclerosis and cardiovascular diseases are often present at the time of diagnosis of type 2 diabetes mellitus. Whether subclinical atherosclerosis can be detected in the pre-diabetic (borderline fasting hyperglycemia) state is not clear. This study investigated the association of impaired fasting glucose (IFG) and coronary artery calcification (CAC), a marker of subclinical atherosclerosis, among participants without a history of coronary heart disease or manifest diabetes mellitus. METHODS: Study participants (aged 45-75 years) of the population-based Heinz Nixdorf Recall Study were categorised into those with normal fasting glucose (glucose <6.1 mmol/l) and those with IFG (glucose >or=6.1 to <7.0 mmol/l), excluding participants with a history of CHD or diabetes mellitus. CAC was assessed by electron-beam computed tomography, and risk factors were assessed by extended interviews, anthropometric measurements and laboratory tests. Various CAC cut-off points were used in multiple logistic and ordinal logistic regression models to estimate ORs and 95% CIs. RESULTS: Of the 2,184 participants, more men had IFG than did women (37% vs 22%). Participants with IFG showed a higher prevalence of CAC > 0 (men OR 1.90, 95% CI 1.33-2.70; women 1.63, 1.23-2.15). Risk factor adjustment weakened this association in both sexes (men 1.63, 1.12-1.36; women 1.26, 0.93-1.70). When the age- and sex-specific 75th percentile was used as the cut-off point for CAC, the association further decreased in men (1.10, 0.81-1.50), but became stronger in women (1.41, 1.02-1.94). CONCLUSIONS/INTERPRETATION: These data support the hypothesis that CAC is already present in the pre-diabetic state and that IFG has a modest and independent impact on the atherosclerotic process. Biological sex appears to modify the association between IFG and CAC.

In-vitro evaluation of coronary stents and 64-detector-row computed tomography using a newly developed model of coronary artery stenosis.

BACKGROUND: Stent implantation is the predominant therapy for non-surgical myocardial revascularization in patients with coronary artery disease. However, despite substantial advances in multidetector computed tomography (MDCT) coronary imaging, a reliable detection of coronary in-stent restenosis is currently not possible. PURPOSE: To examine the ability of 64-detector-row CT to detect and to grade in-stent stenosis in coronary stents using a newly developed ex-vivo vessel phantom with a realistic CT density pattern, artificial stenosis, and a thorax phantom. MATERIAL AND METHODS: Four different stents (Liberté and Lunar ROX, Boston Scientific; Driver, Medtronic; Multi-Link Vision, Guidant) were examined. The stents were placed on a polymer tube with a diameter of 2.5, 3.0, 3.5, or 4.0 mm. Different degrees of stenosis (0%, 30%, 50%, 70-80%) were created inside the tube. For quantitative analysis, attenuation values were measured in the non-stenotic vessel outside the stent, in the non-stenotic vessel inside the stent, and in the stenotic area inside the stent. The grade of stenosis was visually assessed by two observers. RESULTS: All stents led to artificial reduction of attenuation, the least degree of which was found in the Liberté stent (11.3+/-10.2 HU) and the Multi-Link Vision stent (17.6+/-17.9 HU; P = 0.25). Overall, the non-stenotic vessel was correctly diagnosed in 55.5%, the low-grade stenosis in 58.3%, the intermediate stenosis in 63.8%, and the high-grade stenosis in 80.5%. In the 3.0-, 3.5-, and 4.0-mm vessels, in none of the cases was a non-stenotic or low-grade stenotic vessel misdiagnosed as intermediate or high-grade stenosis. The average deviation from the real grade of stenosis was 0.40 for the Liberté stent, 0.46 for the Lunar ROX stent, 0.45 for the Driver stent, and 0.58 for the Multi-Link Vision stent. CONCLUSION: Our ex-vivo data show that non-stenotic stents and low-grade in-stent stenosis can be reliably differentiated from intermediate and high-grade in-stent stenosis in vessels with a diameter of 3 to 4 mm. With regard to artifacts and the grading of stenoses, the Liberté stent was best suited for CT coronary angiography.

In vitro evaluation of coronary stents and in-stent stenosis using a dynamic cardiac phantom and a 64-detector row CT scanner.

INTRODUCTION: The aim of the study was to examine the ability of a 64-slice MDCT to detect in-stent stenoses in an ex vivo model of coronary stents. METHODS: Five different stents (Liberté, Boston Scientific; Driver, Medtronic; Multi-Link Vision, Guidant; Taxus Express, Boston Scientific; Cypher, Cordis) were examined using a dynamic cardiac phantom. The stents were pulled over a vessel model that consists of a polymer tube with diameters of 3.0, 3.5, and 4.0 mm and four different degrees of stenoses (0%; 30%; 50%; 70-80%). This model was moved with a rate of 60 bpm to mimic cardiac motion. To assess the degree of artificial signal reduction (artificial reduction of attenuation (ARA)) by the different stents, attenuation values were measured in the vessel outside the stent, and in the non-stenotic vessel inside the stent. Furthermore the grade of stenosis was assessed by two clinical observers. RESULTS: Highest ARA was found for the Cypher Stent (35 HU), whereas the Liberté Stent presented the lowest ARA (16 HU). Depending on the stent and the vessel diameter, up to 87.5% of the stenoses were correctly diagnosed. In the 3.0 and 3.5 mm vessels, a nonstenotic or low-grade stenotic vessel was diagnosed as intermediate or high-grade stenosis in 22.5%, whereas in the 4.0 mm vessels, this kind of overestimation did not occur. A 50% stenosis was diagnosed as a 30% stenosis in 30%. On the other hand, high-grade stenoses were underestimated in only 10%. On a four-point scale, the average deviation from the real grade of stenosis was 0.21 for the Liberté stent, 0.54 for the Taxus Express stent, 0.29 for Driver stent, 0.62 for the Multi-Link Vision stent, and 0.37 for the Cypher stent. CONCLUSIONS: In a dynamic cardiac phantom model, high grade stenoses in vessels with a diameter of 4 mm could be reliably detected irrespective of the stent type used in this study. Vice versa, high grade stenoses (> or = 50%) could only be ruled out with certainty in vessels with a diameter of 4 mm. In smaller vessels, the ability to correctly diagnose high-grade stenoses was dependent on the type of stent and the imaging artifacts associated with it.

[Current studies on the progression of coronary calcification]. / Aktuelle Studien zur Progression koronarer Kalzifikationen.

UNLABELLED: The quantification of coronary calcification facilitates improved prediction of cardiovascular diseases, in particular in persons with intermediate risk. The importance of serial measurement of coronary calcium in one to two-year intervals for evaluating the course of the disease and therapeutic monitoring after risk modification is unclear. The precise quantification of the progression of arteriosclerosis could contribute to the non-invasive detection of the chronic, often subclinical development of coronary heart disease at an asymptomatic stage of the disease, long before an irreversible clinical event in the pathogenetic cascade, such as sudden cardiac death or myocardial infarction, occurs. An important prerequisite for evaluating changes in the coronary calcium load is detailed knowledge of reproducibility or variability. In addition to a rapid image acquisition time and the use of calibration phantoms, low heart rate and breathing variability, image acquisition in the late systole, overlapping layers (at the expense of radiation dose) and optimized analysis algorithms also contribute to improvement in reproducibility. The limits of variability however are, above all, dependent upon the calcium load itself. Reproducibility is on the average about 10% and thus lies below the highest expected progression, which is about 10-50% per year, depending upon the initial value and pre-existing conditions Only a few studies have identified calcium score progression as an independent predictor for later events. In several studies, calcium score progression was related to the rate of events, but was not independent of other variables. The most important determinant appears to be the calcium score itself. Other relevant determinants are age, gender, diabetes, obesity and renal failure. Whether lipid values significantly influence the progression has not been clarified. CONCLUSION: Further studies on the natural course of coronary heart disease, particularly in the early disease stages, the determinants of progression and the extent to which the calcification progress can be modified are necessary to assess the benefit of serial score measurement for risk stratification. Until then, the repeated radiation exposure cannot be recommended outside of clinical studies.

Residential exposure to traffic is associated with coronary atherosclerosis.

BACKGROUND: Long-term exposure to fine-particulate-matter (PM2.5) air pollution may accelerate the development and progression of atherosclerosis. We investigated the associations of long-term residential exposure to traffic and fine particulate matter with the degree of coronary atherosclerosis. METHODS AND RESULTS: We used baseline data on 4494 participants (age 45 to 74 years) from the German Heinz Nixdorf Recall Study, a population-based, prospective cohort study that started in 2000. To assess exposure differences, distances between residences and major roads were calculated, and annual fine particulate matter concentrations, derived from a small-scale dispersion model, were assigned to each address. The main outcome was coronary artery calcification (CAC) assessed by electron-beam computed tomography. We evaluated the association between air pollution and CAC with logistic and linear regression analyses, controlling for individual level risk factors of coronary atherosclerosis. Compared with participants living >200 m away from a major road, participants living within 50, 51 to 100, and 101 to 200 m had odds ratios of 1.63 (95% CI, 1.14 to 2.33), 1.34 (95% CI, 1.00 to 1.79), and 1.08 (95% CI, 0.85 to 1.39), respectively, for a high CAC (CAC above the age- and gender-specific 75th percentile). A reduction in the distance between the residence and a major road by half was associated with a 7.0% (95% CI, 0.1 to 14.4) higher CAC. Fine particulate matter exposure was associated with CAC only in subjects who had not been working full-time for at least 5 years. CONCLUSIONS: Long-term residential exposure to high traffic is associated with the degree of coronary atherosclerosis.

Noninvasive coronary angiography using 64-detector-row computed tomography in patients with a low to moderate pretest probability of significant coronary artery disease.

PURPOSE: To evaluate the value of 64-detector-row computed tomography for ruling out high-grade coronary stenoses in patients with a low to moderate pretest probability of significant coronary artery disease. MATERIAL AND METHODS: The study included 61 patients with a suspicion of coronary artery disease on the basis of atypical angina or ambiguous findings in noninvasive stress testing and a class II indication for invasive coronary angiography (ICA). All patients were examined by 64-detector-row computed tomography angiography (CTA) and ICA. On a coronary segmental level, the presence of significant (> or = 50% diameter) stenoses was examined. RESULTS: In a total of 915 segments, CTA detected 62 significant stenoses. Thirty-four significant stenoses were confirmed by ICA, whereas 28 stenoses could not be confirmed by ICA. Twenty-two of them showed wall irregularities on ICA, and six were angiographically normal. Accordingly, on a coronary segmental basis, 28 false-positive and 0 false-negative findings resulted in a sensitivity of 100%, a specificity of 96.8%, a positive predictive value of 54.8%, and a negative predictive value of 100%. The diagnostic accuracy was 96.9%. CONCLUSION: Sixty-four-detector-row computed tomography reliably detects significant coronary stenoses in patients with suspected coronary artery disease and appears to be helpful in the selection of patients who need to undergo ICA. Calcified and non-calcified plaques are detected. Grading of stenoses in areas with calcification is difficult. Frequently, stenosis severity is overestimated by 64-detector-row computed tomography.

Assessment of left ventricular function and mass in patients undergoing computed tomography (CT) coronary angiography using 64-detector-row CT: comparison to magnetic resonance imaging.

PURPOSE: To quantify left ventricular function and mass derived from retrospectively ECG-gated 64-detector-row computed tomography coronary angiography data sets in comparison to cine magnetic resonance (MR) imaging as the reference standard. We hypothesized that the administration of beta-blockers prior to multidetector computed tomography (MDCT) coronary angiography has a significant impact on left ventricular functional parameters. MATERIAL AND METHODS: Multiplanar reformations in the short-axis orientation were calculated from axial contrast-enhanced CT images in 21 patients (16 male, five female; age range 41-75 years, mean 64.3+/-6.8 years) referred for CT coronary angiography. Patients whose heart rates exceeded 60 bpm received 5 mg bisoprolol orally 1 hour before the MDCT examination. In case of insufficient heart-rate reduction, up to four vials (20 mg) of metoprolol were injected intravenously. The end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), cardiac output (CO), and left ventricular mass (LVM) of the reformatted images were analyzed compared to volumetric measurements based on continuous short-axis steady-state free-precession cine MR sequences (TR 3 ms, TE 1.5 ms, FA 60 degrees ). RESULTS: On average, each patient received 15.5 mg metoprolol (range 0-20 mg) and 3.85 mg bisoprolol (range 0-5 mg). The mean heart rate was 56+/-5 bpm during CT and 73+/-9 bpm during MRI examination. This difference was statistically significant (P<0.05). Mean EDV and ESV measured on MDCT were significantly higher compared to MR (MDCT vs. MR: EDV 164.2+/-52.5 vs. 144.2+/-46.7 ml, ESV 77.3+/-46.6 vs. 63.8+/-47.3 ml; P<0.05). Mean EF and CO derived from MDCT images were significantly lower compared to MR (MDCT vs. MR: EF 55.4+/-11.8 vs. 59.3+/-15.4%, CO 4822+/-779 vs. 5755+/-1267 ml; P<0.05). Mean SV and LVM were not significantly different between both methods (MDCT vs. MR: SV 86.8+/-18.1 vs. 80.3+/-15.6 ml, P = 0.44; LVM 132.4+/-42.5 vs. 138.7+/-39.1 g, P = 0.31). CONCLUSION: Left ventricular volumes assessed by the newest-generation MDCT scanners are significantly higher compared with MRI, whereas ejection fraction and cardiac output are significantly lower in MDCT. This appears to be a result of the frequent application of beta-blockers prior to MDCT examinations.

Intraoperative coronary graft flow determination--does it have a prognostic value for midterm graft patency?

OBJECTIVE: To characterise the prognostic value of intraoperative ultrasonic graft flow determination during CABG for mid-term patency. METHODS: From 01/2000 to 08/2003 3146 CABG procedures were performed at our institution. Graft flow was determined in all patients. Lumen diameter was given in mm and a sclerosis score was applied for the target vessel. 100 of these patients (3.2%) underwent postoperative coronary angiography at a mean time interval of 8.0 +/- 0.5 months. RESULTS: In 100 patients, 114 LITA and 204 venous anastomoses were performed. At re-angiography 112 LITA (98%) and 174 venous (85%) anastomoses were patent. The amount of occluded LITA grafts was to low to perform statistical analyses. Mean graft flow of patent vein grafts was 48 +/- 2 ml/min vs. 32 +/- 4 ml/min in occluded vein grafts (p = 0.001). After multiple logistic regression analysis, only intraoperative vein graft flow was found to be a predictor for patency at mid-term (p = 0.005, odds ratio 0.97, 95% confidence interval (CI) from 0.95-0.99). No differences were found concerning sclerosis scores or vessel lumen between patent and occluded grafts. CONCLUSIONS: Significant differences concerning intraoperative graft flow were found between vein grafts patent or occluded at re-angiography. The predictive power of intraoperative vein graft flow for mid-term patency was confirmed by multiple logistic regression analysis.