Use of coronary physiology to guide revascularization in clinical practice: results of the F(FR)2 registry.

BACKGROUND: Despite the recommendation of coronary physiology to guide revascularization in angiographically intermediate stenoses without established correlation to ischemia, its uptake in clinical practice is slow. AIMS: This study aimed to analyze the use of coronary physiology in clinical practice. METHODS: Based on a multicenter registry (Fractional Flow Reserve Fax Registry, F(FR)2, ClinicalTrials.gov identifier NCT03055910), clinical use, consequences, and complications of coronary physiology were systematically analyzed. RESULTS: F(FR)2 enrolled 2,000 patients with 3,378 intracoronary pressure measurements. Most measurements (96.8%) were performed in angiographically intermediate stenoses. Out of 3,238 lesions in which coronary physiology was used to guide revascularization, revascularization was deferred in 2,643 (78.2%) cases. Fractional flow reserve (FFR) was the most common pressure index used (87.6%), with hyperemia induced by an intracoronary bolus of adenosine in 2,556 lesions (86.4%) and intravenous adenosine used for 384 measurements (13.0%). The route of adenosine administration did not influence FFR results (change-in-estimate -3.1% for regression model predicting FFR from diameter stenosis). Agreement with the subsequent revascularization decision was 93.4% for intravenous and 95.0% for intracoronary adenosine (p = 0.261). Coronary artery occlusion caused by the pressure wire was reported in two cases (0.1%) and dissection in three cases (0.2%), which was fatal once (0.1%). CONCLUSIONS: In clinical practice, intracoronary pressure measurements are mostly used to guide revascularization decisions in angiographically intermediate stenoses. Intracoronary and intravenous administration of adenosine seem equally suited. While the rate of serious complications of wire-based intracoronary pressure measurements in clinical practice seems to be low, it is not negligible.

Coronary computed tomography angiography (CCTA) in patients with suspected stable coronary artery disease (CAD): diagnostic impact and clinical consequences in the German Cardiac CT Registry depending on stress test results.

To evaluate diagnostic impact of clinical use of coronary computed tomography angiography (CCTA) in patients with suspected stable coronary artery disease (CAD) and its consequences in daily practice for patient management, depending on stress test results in daily practice. Between 2009 and 2014 of a total population of 1352 patients of the German Cardiac Computed Tomography (CT) Registry who had previously undergone stress tests, CCTA visualizations were carried out on the coronary arteries with suspected stable CAD. Patients were divided into three groups according to stress test results: Group 1 with inconclusive (n = 178, 13.2%), Group 2 with ischemia in stress test (n = 372, 27.5%) and Group 3 without ischemia in stress test (n = 802, 59.3%). The test of preference was the stress electrocardiogram (ECG), which was performed more frequently in patients without ischemia in stress test as compared to those with ischemia (96.3% vs. 93.0%, p = 0.015). The incidence of detected obstructive CAD was lower in patients with suggested ischemia in stress test as compared to patients with inconclusive results (14.1% vs. 21.1%, p = 0.037). There was no difference in the incidence of an obstructive CAD in patients with and without ischemia in stress test (14.1% vs. 15.8%, p = 0.440). CCTA is a reliable, non-invasive option for ruling-out obstructive CAD irrespective of the stress test result.

German cardiac CT registry: indications, procedural data and clinical consequences in 7061 patients undergoing cardiac computed tomography.

Cardiac computed tomography permits quantification of coronary calcification as well as detection of coronary artery stenoses after contrast enhancement. Moreover, cardiac CT offers high-resolution morphologic and functional imaging of cardiac structures which is valuable for various structural heart disease interventions and electrophysiology procedures. So far, only limited data exist regarding the spectrum of indications, image acquisition parameters as well as results and clinical consequences of cardiac CT examinations using state-of-the-art CT systems in experienced centers. Twelve cardiology centers with profound expertise in cardiovascular imaging participated in the German Cardiac CT Registry. Criteria for participation included adequate experience in cardiac CT as well of the availability of a 64-slice or newer CT system. Between 2009 and 2014, 7061 patients were prospectively enrolled. For all cardiac CT examinations, patient parameters, procedural data, indication and clinical consequences of the examination were documented. Mean patient age was 61 ± 12 years, 63% were males. The majority (63%) of all cardiac CT examinations were performed in an outpatient setting, 37% were performed during an inpatient stay. 91% were elective and 9% were scheduled in an acute setting. In most examinations (48%), reporting was performed by cardiologists, in 4% by radiologists and in 47% of the cases as a consensus reading. Cardiac CT was limited to native acquisitions for assessment of coronary artery calcification in 9% of patients, only contrast-enhanced coronary CT angiography was performed in 16.6% and combined native and contrast-enhanced coronary CT angiography was performed in 57.7% of patients. Non-coronary cardiac CT examinations constituted 16.6% of all cases. Coronary artery calcification assessment was performed using prospectively ECG-triggered acquisition in 76.9% of all cases. The median dose length product (DLP) was 42 mGy cm (estimated effective radiation dose of 0.6 mSv). Coronary CT angiography was performed using prospectively ECG-triggered acquisition in 77.3% of all cases. Tube voltage was 120 kV in 67.8% of patients and 100 kV in 30.7% of patients, with a resultant median DLP of 256 mGy cm (estimated effective dose of 3.6 mSv). Clinical consequences of cardiac CT were as follows: in 46.8% of the cases, invasive coronary angiography could be avoided; ischemia testing was recommended in 4.7% of the cases, invasive coronary angiography was recommended in 16.4% of the cases and change in medication in 21.6% of the examinations. Cardiac CT is performed in the majority of patients for non-invasive evaluation of the coronary arteries. CT frequently resulted in medication change, and otherwise planned downstream testing including invasive angiography could be avoided in a high percentage of patients. Radiation exposure in experienced centers is relatively low.

Declining radiation dose of coronary computed tomography angiography: German cardiac CT registry experience 2009-2014.

BACKGROUND: Coronary computed tomography angiography (CTA) is increasingly used as a test to rule out coronary artery disease (CAD) in patients with a low to intermediate pre-test probability of the disease. We used the database of the German CT registry, collected between 2009 and 2014 in a broad patient population, to analyze contemporary radiation dose associated with coronary CTA in clinical practice. PATIENTS AND METHODS: The prospective observational registry included a total of 7061 patients ≥18 years, referred to 12 participating centers for a clinically indicated cardiac CT examination. All centers were cardiology units well experienced in CTA and used multi-slice CT scanners with at least 64 rows. Coronary CTA was performed in a subset of 5001 patients, 59.6 ± 11.8 years, body mass index (BMI) 26.9 ± 4.5 kg/m2, 38% females. Three time periods with approximately equal numbers of patients were created (01/09-03/10, 04/10-03/11, 04/11-07/14). The dose-length product of all examinations and derived effective dose in mSv (conversion factor k = 0.014) as well as the influence of patient characteristics on dose were compared for the three time periods. RESULTS: BMI and proportion of female patients remained stable over time, and mean heart rate decreased from 60.3 ± 9.0 to 58.5 ± 9.3 bpm from the first to the last time period (p < 0.001). Overall, the mean effective dose of coronary CTA was 3.6 mSv (Q1 1.8 mSv, Q3 7.4 mSv). Within the three time periods, it declined from 5.6 (2.7, 8.6) mSv during the first to 4.8 (2.1, 8.2) mSv during the second and 2.5 (1.3, 4.6) mSv during the last time period (p < 0.001). Paralleling the decline in radiation dose over time, the proportion of prospectively ECG-triggered examinations increased (68, 79, 83%; p < 0.001), and the proportion of examinations with retrospective gating and no tube current modulation decreased (5.3, 4.0, 1.6%; p < 0.001). Tube current (mAs) and voltage (kV) both decreased over time. In multivariable analysis, besides earlier time period, further independent predictors of an increased radiation dose were older age, higher heart rate, and higher BMI as well as the technical factors higher mAs, higher kV, and retrospective gating. At three sites, CT scanners with improved technology were installed during the last time period. CONCLUSIONS: In current clinical practice among German cardiology units with specific expertise in cross-sectional cardiovascular imaging, overall radiation dose of coronary CTA was comparably low. Over time, a decline in radiation dose was demonstrated, probably due to a combination of improvements in data acquisition protocols and patient preparation as well as installation of new CT scanners with advanced technology.

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.

One-year clinical outcomes with abciximab in acute myocardial infarction: results of the BRAVE-3 randomized trial.

PURPOSE: In the Bavarian Reperfusion Alternatives Evaluation (BRAVE)-3 study upstream administration of abciximab additional to 600 mg clopidogrel loading did not reduce the infarct size in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary interventions. The aim of this study was to investigate 1-year clinical outcomes in the BRAVE-3 study patients. METHODS: A total of 800 patients with acute STEMI within 24 h from symptom onset, all treated with 600 mg of clopidogrel were randomized in a double-blind fashion to receive either abciximab (n = 401) or placebo (n = 399) in the intensive care unit before being sent to the catheterization laboratory. RESULTS: The main outcome of interest of the present study, the composite of death, recurrent myocardial infarction, stroke or revascularization of the infarct-related artery (IRA) at 1 year, was 23.0% (92 patients) in the abciximab versus 25.7% (102 patients) in the placebo group [relative risk (RR) = 0.90, 95% confidence interval (CI) 0.67-1.20; P = 0.46]. The combined incidence of death, recurrent myocardial infarction or stroke was 9.3% in the abciximab group versus 6.0% in the placebo group (RR = 1.55, 95% CI 0.93-2.58; P = 0.09). There was a significant reduction of the IRA revascularization with abciximab compared to placebo (16.3 vs. 22.3%, RR = 0.71, 95% CI 0.52-0.98; P = 0.04). CONCLUSION: In patients with STEMI, all receiving 600 mg clopidogrel, abciximab did not improve overall clinical outcomes at 1 year after primary coronary stenting.

Abciximab in patients with acute ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention after clopidogrel loading: a randomized double-blind trial.

BACKGROUND: The glycoprotein IIb/IIIa receptor inhibitor abciximab has improved the efficacy of primary percutaneous coronary interventions in patients with acute myocardial infarction. However, it is not known whether abciximab remains beneficial after adequate clopidogrel loading in patients with acute ST-segment-elevation myocardial infarction. METHODS AND RESULTS: A total of 800 patients with acute ST-segment-elevation myocardial infarction within 24 hours from symptom onset, all treated with 600 mg clopidogrel, were randomly assigned in a double-blind fashion to receive either abciximab (n=401) or placebo (n=399) in the intensive care unit before being sent to the catheterization laboratory. The primary end point, infarct size measured by single-photon emission computed tomography with technetium-99m sestamibi before hospital discharge, was 15.7+/-17.2% (mean+/-SD) of the left ventricle in the abciximab group and 16.6+/-18.6% of the left ventricle in the placebo group (P=0.47). At 30 days, the composite of death, recurrent myocardial infarction, stroke, or urgent revascularization of the infarct-related artery was observed in 20 patients in the abciximab group (5.0%) and 15 patients in the placebo group (3.8%) (relative risk, 1.3; 95% CI, 0.7 to 2.6; P=0.40). Major bleeding complications were observed in 7 patients in each group (1.8%). CONCLUSIONS: Upstream administration of abciximab is not associated with a reduction in infarct size in patients presenting with acute myocardial infarction within 24 hours of symptom onset and receiving 600 mg clopidogrel.

Effect of intensive versus standard lipid-lowering treatment with atorvastatin on the progression of calcified coronary atherosclerosis over 12 months: a multicenter, randomized, double-blind trial.

BACKGROUND: Recent clinical trials have suggested that intensive versus standard lipid-lowering therapy provides for additional benefit. Electron-beam computed tomography provides the opportunity to quantify the progression of coronary artery calcification (CAC) in serial measurements. METHODS AND RESULTS: In a multicenter, randomized, double-blind trial, 471 patients (age 61+/-8 years) who had no history of coronary artery disease and no evidence of high-grade coronary stenoses (>50% diameter reduction) were randomized if they had > or =2 cardiovascular risk factors and moderate calcified coronary atherosclerosis as evidenced by a CAC score > or =30. Patients were assigned to receive 80 mg or 10 mg of atorvastatin per day over 12 months. Progression of CAC volume scores could be analyzed in 366 patients. After pretreatment with 10 mg of atorvastatin for 4 weeks, 12 months of study medication reduced LDL cholesterol from 106+/-22 to 87+/-33 mg/dL in the group randomized to receive 80 mg of atorvastatin (P<0.001), whereas levels remained stable in the group randomized to receive 10 mg (108+/-23 at baseline, 109+/-28 mg/dL at the end of the study, P=NS). The mean progression of CAC volume scores, corrected for the baseline CAC volume score, was 27% (95% CI 20.8% to 33.1%) in the 80-mg atorvastatin group and 25% (95% CI 19.1% to 30.8%) in the 10-mg atorvastatin group (P=0.65). CAC progression showed no relationship with on-treatment LDL cholesterol levels. CONCLUSIONS: We did not observe a relationship between on-treatment LDL cholesterol levels and the progression of calcified coronary atherosclerosis. Over a period of 12 months, intensive atorvastatin therapy was unable to attenuate CAC progression compared with standard atorvastatin therapy. The possibility remains that the time window was too short to demonstrate an effect.

Diagnostic value of maximum intensity projections versus source images for assessment of contrast-enhanced three-dimensional breath-hold magnetic resonance coronary angiography.

RATIONALE AND OBJECTIVES: We compared maximum intensity projections (MIP) versus original source images (SI) in respect to detection of coronary artery stenoses by means of magnetic resonance (MR) coronary angiography. METHODS: MR coronary angiography was performed on 61 patients. MIP and SI were independently evaluated as to presence of significant stenoses in the proximal and midcoronary segments and compared with x-ray angiography. RESULTS: A total of 315 of 427 (74%) coronary artery segments could be evaluated in MIP and 328 of 427 (77%) in SI. In segments able to be evaluated, MIP images demonstrated 84% (54/64) sensitivity and 87% (219/251) specificity, whereas SI images showed 85% (58/68) sensitivity and 90% (235/260) specificity. Overall accuracy was 87% (273/310) for MIP and 89% (293/328) for SI. There was no statistically significant difference between both modalities. CONCLUSIONS: The MIP reconstructions showed comparable accuracy to unprocessed SI. However, MIP postprocessing is compromised by a higher number of images that were unable to be evaluated due to overlap of coronary arteries with adjacent cardiac structures.

Comparison of contrast-enhanced breath-hold and free-breathing respiratory-gated imaging in three-dimensional magnetic resonance coronary angiography.

Suppression of respiratory motion is one of the major challenges of magnetic resonance (MR) coronary angiography. Two approaches to compensate for respiratory motion have often been proposed: breath-hold (BH) and free-breathing respiratory-gated (FBRG) imaging. So far, however, these approaches have never been directly compared. MR coronary angiography was performed in 32 patients with suspected coronary artery disease. MR data were acquired using contrast-enhanced BH and FBRG 3-dimensional MR coronary angiographic techniques. MR images were compared with regard to image quality using quantitative parameters and with regard to accuracy for stenosis detection in the proximal and mid-coronary segments in comparison to x-ray angiography. With regard to image quality, BH was superior to FBRG. Signal-to-noise ratio was 29.1 +/- 10.7 for BH versus 18.8 +/- 9.7 for FBRG (p <0.05) and contrast-to-noise was 18.0 +/- 7.4 for BH versus 11.3 +/- 7.9 for FBRG (p

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.

A direct comparison of noninvasive coronary angiography by electron beam tomography and navigator-echo-based magnetic resonance imaging for the detection of restenosis following coronary angioplasty.

RATIONALE AND OBJECTIVES: To compare electron beam tomography (EBT) with MR imaging (MRI) for detection of restenosis after coronary angioplasty (PTCA). METHODS: One hundred eighteen patients after PTCA were investigated. By EBT, 50 axial images were acquired (3-mm slice thickness, 120-160 mL radiographic contrast agent). MRI was performed using respiratory-gated sequences (24-48 cross-sections, 2-mm slice thickness, 20 mL Gd-DTPA). EBT and MRI images were evaluated concerning high-grade post-PTCA restenosis (> or = 70%) and validated against coronary angiography. RESULTS: In EBT, 28 patients and in MRI, 31 patients were not evaluable. In the remaining patients, sensitivity for restenosis detection was 90% in EBT (17/19) and 73% in MRI (11/15; P = 0.370). In EBT, specificity was significantly higher (66% vs. 49%, P = 0.043). Overall accuracy was 71% for EBT and 53% for MRI (P = 0.014). CONCLUSIONS: For the detection of high-grade restenosis after PTCA, EBT demonstrated significantly higher accuracy than MRI.