Gender differences in plaque characteristics of culprit lesions in patients with ST elevation myocardial infarction.

There is limited research on plaque characteristics of ST elevation myocardial infarction (STEMI) patients according to the gender and age. 280 Consecutive STEMI patients who underwent VH-IVUS imaging on culprit before percutaneous coronary intervention (PCI) were enrolled in this study. Women were significantly older than men (69.8 ± 10 vs. 55.9 ± 11.3, p < 0.001). After propensity matching, men had higher plaque burden (79.7 ± 7.8 vs. 73.7 ± 13.0 %, p = 0.010), more fibro-fatty tissue (12.8 ± 9.9 vs. 9.5 ± 6.8 %, p = 0.04) and less dense calcium than women (8.4 ± 5.8 vs. 12.3 ± 8.7 %, p = 0.007). Subgroups dividing by 50, 65, 75 years old, plaque burden was higher in elderly men aged 66-75 years compared to the young men aged less than 50 (75.5 ± 9.2 vs. 68.4 ± 10.1 %, p = 0.012). And middle aged men ranged 51-65 years showed significantly more plaque burden at minimal lumen area site than matched aged women (77.5 ± 8.0 vs. 69.0 ± 17.6 %, p = 0.012). Elderly women aged 66-75 years showed significantly more necrotic core (28.6 ± 7.3 %) and dense calcium (14.9 ± 7.5 %) compared to all the younger or matched subgroups of men. These differences in plaque composition are blunted in the very elderly of men and women aged over 75 years. The findings may explain the gender differences in clinical prognosis in STEMI patients.

Differences in ward-to-cath lab systolic blood pressure predicts long-term adverse outcomes after drug-eluting stent implantation.

We sought to investigate the effect of ward-to-cath lab blood pressure (BP) differences on long-term clinical outcomes in patients undergoing percutaneous coronary intervention (PCI) with drug-eluting stent (DES). There are limited data available on the association between PCI with DES and BP differences on long-term clinical outcomes. This study enrolled 994 patients who underwent PCI with DES from March 2003 to August 2007. Resting BP was measured in a ward environment before transfer to the cardiac catheterization lab (cath lab), and again when the patient was laid down on the cath lab table. Patients were divided into two groups according to the difference in ward-to-cath lab systolic BP. Large difference group (n = 383) was defined as the absolute systolic difference of >20 mmHg and small difference group (n = 424) as the absolute systolic difference of ≤20 mmHg. The primary endpoints were all-cause mortality, cardiac death, nonfatal myocardial infarction and stroke. A total of 807 patients (mean age 60 ± 10 years, 522 males) received follow-up for 5.1 ± 2.4 years. The rate of all-cause mortality was significantly higher in the large difference group compared to the small difference group (6.6 vs. 2.8 %; adjusted hazard ratio (HR) 2.43; 95 % confidence interval (CI) 1.22-4.83; p = 0.012). There were higher cardiac deaths seen in the large difference group compared to the small difference group (3.9 vs. 1.4 %; adjusted HR 2.84; 95 % CI 1.1-7.31; p = 0.031). Stroke (2.4 vs. 1.2 %, p = 0.125) and TVR (3.7 vs. 1.7 %, p = 0.051) had higher trends in the large difference group compared to the small difference group. The composite of primary endpoints (all-cause mortality, cardiac death, nonfatal MI and stroke) occurred more frequently in the large difference group compared to the small difference group (10.0 vs. 6.4 %; adjusted HR 1.71; 95 % CI 1.04-2.81; p = 0.033). A difference in ward-to-cath lab systolic BP of >20 mmHg may contribute to increased adverse outcomes in the form of all-cause mortality and cardiac deaths in patients undergoing PCI with DES.

Vasoconstrictor component of atherothrombotic culprit lesions in ST-segment elevation myocardial infarction.

OBJECTIVE: The vasoconstrictor component of atherothrombotic culprit lesions in ST-elevation myocardial infarction (STEMI) patients has not been fully investigated. This study was aimed at assessing the vasoconstrictor component of atherothrombotic culprit lesions in patients with STEMI receiving primary percutaneous coronary intervention (PCI). METHODS: A group of 100 patients with STEMI were enrolled prospectively. Baseline coronary angiography achieving normal antegrade flow was followed by 200 µg of intracoronary nitroglycerin (NTG) injection and repeat coronary angiography at the same projection view for culprit lesions was performed. End points were the changes in lesion length, reference vessel diameter, minimal lumen diameter, and diameter stenosis by quantitative coronary analysis before and after NTG injection. RESULTS: Reference vessel diameter (2.7 ±â€¯0.5 mm vs. 2.9 ±â€¯0.5 mm, p < 0.001) and minimal lumen diameter (0.9 ±â€¯0.4 mm vs. 1.2 ±â€¯0.5 mm, p < 0.001) increased after NTG injection, whereas lesion length (24.1 ±â€¯7.4 mm vs. 23.4 ±â€¯7.6 mm, p = 0.001) and diameter stenosis (66.6 ±â€¯14.8% vs. 58.3 ±â€¯16.1%, p < 0.001) decreased. The median percentage change of diameter stenosis was -4.0% (Interquartile range: -13.8% to -1.0%), which was used as the cut-off value to divide the cohort into NTG responder or nonresponder groups accordingly. Total stent length was significantly shorter in the responder group compared with the nonresponder group (27.4 ±â€¯11.6 mm vs. 33.7 ±â€¯16.8 mm, p = 0.042). CONCLUSION: This study showed the presence of a vasoconstrictor component in atherothrombotic culprit lesions in STEMI patients receiving primary PCI. Vasodilating effort by NTG may decrease stent length used for culprit lesions.

Plaque characteristics and inflammatory markers for the prediction of major cardiovascular events in patients with ST-segment elevation myocardial infarction.

To investigate the clinical utility of culprit plaque characteristics and inflammatory markers for the prediction of future cardiovascular events in patients with ST-segment elevation myocardial infarction (STEMI) with successful drug-eluting stent (DES) implantation. We evaluated 172 STEMI patients with successful primary percutaneous coronary intervention (PCI) with DES using pre-PCI high-sensitivity C-reactive protein (hs-CRP), neutrophil-to-lymphocyte ratio (NLR) and pre-PCI intravascular ultrasound virtual histology (IVUS-VH) of culprit lesions. The incidence of major adverse cardiovascular events (MACE) including all-cause mortality, non-fatal MI, stroke and late revascularization were recorded during hospitalization and follow-up. During follow-up (median 41 months), the incidence of MACE did not significantly differ among patients with or without all 3 high-risk plaque features on IVUS-VH (15.1 vs. 16.2%; p = 0.39). In contrast, patients with elevated hs-CRP and NLR levels were at significant risk for MACE [32.7 vs. 5.8%; hazard ratio (HR) 7.85; p < 0.001 and 43.9 vs. 6.9%; HR 8.44; p < 0.001, respectively]. High-risk plaque features had no incremental usefulness to predict future MACE. However, the incorporation of hs-CRP and NLR into a model with conventional clinical and procedural risk factors significantly improved the C-statistic for the prediction of MACE (0.76-0.89; p = 0.04). High-risk plaque features identified by IVUS-VH in culprit lesions were not associated with future MACE in patients with STEMI receiving DES. However, elevated hs-CRP and NLR levels were significantly associated with poorer outcomes and had incremental predictive values over conventional risk factors.

A Comparison of Peri-Procedural Myocardial Infarction between Paclitaxel-Coated Balloon and Drug-Eluting Stent on De Novo Coronary Lesions.

PURPOSE: This study compared the impact of paclitaxel-coated balloons (PCB) or drug eluting stents (DES) on peri-procedural myocardial infarction (PMI) on de novo coronary lesion in stable patients. MATERIALS AND METHODS: In this observational study, we compared the incidence of PMI amongst patients with single vessel de novo coronary lesions who underwent treatment with a PCB or DES. Propensity score-matching analysis was used to assemble a cohort of patients with similar baseline characteristics. PMI was classified as myocardial infarction occurring within 48 hours after percutaneous coronary intervention with a threshold of 5 x the 99th percentile upper reference limit of normal for creatine kinase-myocardial band (CK-MB) or troponin T (TnT). RESULTS: One hundred four patients (52 receiving PCB and 52 receiving DES) were enrolled in this study. The peak mean values of CK-MB and TnT were significantly higher in the DES group. There was a significantly higher rate of PMI in the DES group (23.1% vs. 1.9%, p=0.002). Total occlusion of the side-branch occurred in two patients treated with DES, while no patients treated with PCB. In multivariable analysis, DES was the only independent predictor of PMI compared with PCB (odds ratio 42.85, 95% confidence interval: 3.44-533.87, p=0.004). CONCLUSION: Treatment with a PCB on de novo coronary lesion might be associated with a significant reduction in the risk of PMI compared to DES.

Prognostic Utility of Neutrophil-to-Lymphocyte Ratio on Adverse Clinical Outcomes in Patients with Severe Calcific Aortic Stenosis.

BACKGROUND: Inflammation is an important factor in the pathogenesis of calcific aortic stenosis (AS). We aimed to evaluate the association between an inflammatory marker, neutrophil-to-lymphocyte ratio (NLR) and major adverse cardiovascular events (MACE) in patients with severe calcific AS. METHODS: A total of 336 patients with isolated severe calcific AS newly diagnosed between 2010 and 2015 were enrolled in this study. Using Cox proportional hazards (PH) regression models, we investigated the prognostic value of NLR adjusted for baseline covariates including logistic European System for Cardiac Operative Risk Evaluation score (EuroSCORE-I) and undergoing aortic valve replacement (AVR). We also evaluated the clinical relevance of NLR risk groups (divided into low, intermediate, high risk) as categorized by NLR cutoff values. MACE was defined as a composite of all-cause mortality, cardiac death and non-fatal myocardial infarction during the follow-up period. RESULTS: The inflammatory marker NLR was an independent prognostic factor most significantly associated with MACE [hazard ratio (HR), 1.06; 95% confidence interval (CI), 1.04-1.09; p-value <0.001]. The goodness-of-fit and discriminability of the model including EuroSCORE-I and AVR (loglikelihood difference, 15.49; p-value <0.001; c-index difference, 0.035; p-value = 0.03) were significantly improved when NLR was incorporated into the model. The estimated Kaplan-Meier survival rates at 5 years for the NLR risk groups were 84.6% for the low risk group (NLR ≤ 2), 67.7% for the intermediate risk group (2 < NLR ≤ 9), and 42.6% for the high risk group (NLR > 9), respectively. CONCLUSION: The findings of the present study demonstrate the potential utility of NLR in risk stratification of patients with severe calcific AS.

Serial Morphological and Functional Assessment of the Paclitaxel-coated Balloon for de Novo Lesions.

INTRODUCTION AND OBJECTIVES: There is limited data on the serial morphological and functional assessment of paclitaxel-coated balloon treatment using coronary angiography, optical coherence tomography, and fractional flow reserve. METHODS: In this prospective, single-center observational study, patients with de novo lesions were treated with the paclitaxel-coated balloon. Serial angiographic, optical coherence tomography and fractional flow reserve measurements were performed before and after plain old balloon angioplasty, as well as at 9-month follow-up. RESULTS: Twenty patients (21 lesions) were enrolled in this study. The reference vessel diameter was 2.68±0.34mm and late luminal loss was 0.01±0.21mm. The median changes in the minimal lumen area between pre- and postplain old balloon angioplasty, and postplain old balloon angioplasty and follow-up were an increase of 75.2% [interquartile range of 37.2 to 164.7] and 50.0% [interquartile range of 1.1% to 64.5%], respectively. Intimal dissections were seen in all postprocedural optical coherence tomography images, and 66.6% of them were sealed on follow-up optical coherence tomography (median 278 days). The fractional flow reserve distal to the target lesion was 0.71±0.14 predilatation, 0.87±0.04 postdilatation, and 0.83±0.08 at follow-up. CONCLUSIONS: The paclitaxel-coated balloon restores coronary blood flow by means of plaque modification, causing an increment in minimal lumen area. At 9-month follow-up, coronary flow was sustained and the luminal patency was the result of suppressed luminal narrowing progression from local drug effects on the de novo coronary lesions.

Comparison of Paclitaxel-Coated Balloon Treatment and Plain Old Balloon Angioplasty for De Novo Coronary Lesions.

PURPOSE: This study compared the angiographic outcomes of paclitaxel-coated balloon (PCB) versus plain old balloon angioplasty (POBA) treatment for de novo coronary artery lesions. At present, there is no available data comparing the efficacy of PCB versus POBA for the treatment of de novo coronary lesions. MATERIALS AND METHODS: This multicenter retrospective observational study enrolled patients with de novo coronary lesions with a reference vessel diameter between 2.5 mm and 3.0 mm and lesion length ≤ 24 mm who were successfully treated with PCB or POBA. Angiographic measurements and quantitative coronary analysis were performed before and after the procedure, and at 9 months follow-up. RESULTS: A total of 72 patients (49 receiving PCB and 23 receiving POBA) were enrolled in this study. Late luminal loss was -0.12 ± 0.30 mm in the PCB group and 0.25 ± 0.50 mm in the POBA group (p<0.001). There was a higher percentage of binary restenosis (diameter stenosis ≥ 50%) in POBA, compared to PCB (30.4%, n=7 vs. 4.1%, n=2, p<0.001). Target vessel revascularization was higher in the POBA group (13.0%, n=3 vs. 0%, p=0.033). CONCLUSION: PCB treatment of de novo coronary lesions showed better 9-month angiographic outcomes than POBA treatment alone.

Serum Phosphorus Concentration and Coronary Artery Calcification in Subjects without Renal Dysfunction.

Serum phosphorus (P) concentration is associated with coronary artery calcification (CAC) as well as cardiovascular events in patients with chronic kidney disease. It has been suggested that this relationship is extended to subjects without renal dysfunction, but further explorations in diverse races and regions are still needed. We performed a cross-sectional study of 2,509 Korean subjects (Far Eastern Asian) with an estimated glomerular filtration rate of ≥60 ml/min/1.73 m2 and who underwent coronary computerized tomography. Serum P concentration was divided into pre-determined 4 categories: ≤3.2, 3.2< to ≤3.6, 3.6< to ≤4.0 and >4.0 mg/dL. Agatston score (AS), an index of CAC, was divided into 3 categories: 0, 0< to ≤100, and >100. A multinomial logit model (baseline outcome: AS = 0) was applied to estimate the odds ratio (OR) for each serum P category (reference: ≤3.2mg/dL). Mean age of subjects was 53.5±9.1 years and 36.9% were female. In the adjusted model, serum P concentration of 3.6< to ≤4.0 mg/dL and >4.0 mg/dL showed high ORs for AS of >100 [OR: 1.58, 95% confidence interval (CI): 1.04-2.40 and OR: 2.11, 95% CI: 1.34-3.32, respectively]. A unit (mg/dL) increase in serum P concentration was associated with 50% increase in risk of AS >100 (OR: 1.50, 95% CI: 1.16-1.94). A higher serum P concentration, even within a normal range, may be associated with a higher CAC in subjects with normal renal function.

Serial Morphological Changes of Side-Branch Ostium after Paclitaxel-Coated Balloon Treatment of De Novo Coronary Lesions of Main Vessels.

PURPOSE: The effects on the side-branch (SB) ostium, following paclitaxel-coated balloon (PCB) treatment of de novo coronary lesions of main vessels have not been previously investigated. This study was aimed at evaluating the serial morphological changes of the SB ostium after PCB treatment of de novo coronary lesions of main vessels using optical coherence tomography (OCT). MATERIALS AND METHODS: This prospective, single-center observational study enrolled patients with de novo lesions, which were traversed by at least one SB (≥1.5 mm) and were treated with PCB. The SB ostium was evaluated with serial angiographic and OCT assessments pre- and post-procedure, and at 9-months follow-up. RESULTS: Sixteen main vessel lesions were successfully treated with PCB, and 26 SBs were included for analysis. Mean SB ostial lumen area increased at 9-months follow-up (0.92±0.68 mm² pre-procedure, 1.03±0.77 mm² post-procedure and 1.42±1.18 mm² at 9-months). The SB ostial lumen area gain was 0.02±0.24 mm² between pre- and post-procedure, 0.37±0.64 mm² between post-procedure and 9-months, and 0.60±0.93 mm² between pre-procedure and 9-months. The ostial lumen area increased by 3.9% [interquartile range (IQR) of -33.3 to 10.4%] between pre- and post-procedure, 52.1% (IQR of -0.7 to 77.3%) between post-procedure and 9-months and 76.1% (IQR of 18.2 to 86.6%) between pre-procedure and 9-months. CONCLUSION: PCB treatment of de novo coronary lesions of main vessels resulted in an increase in the SB ostial lumen area at 9-months.

Prediction of Coronary Atherosclerotic Ostial Lesion with a Damping of the Pressure Tracing during Diagnostic Coronary Angiography.

PURPOSE: When performing coronary angiography (CAG), diagnostic catheter intubation to the ostium can cause damping of the pressure tracing. The aim of this study was to determine the predictors of atherosclerotic ostial stenosis in patients showing pressure damping during CAG. MATERIALS AND METHODS: In total, 2926 patients who underwent diagnostic CAG were screened in this study. Pressure damping was defined as an abrupt decline of the coronary blood pressure with a blunted pulse pressure after engagement of the diagnostic catheter. According to CAG and intravascular ultrasound (IVUS), we divided damped ostia into two groups: atherosclerotic ostial lesion group (true lesion group) and non-atherosclerotic ostium group (false lesion group). Clinical and angiographic characteristics were compared between the two groups. RESULTS: The overall incidence of pressure damping was 2.3% (68 patients and 76 ostia). Among the pressure damped ostia, 40.8% (31 of 76 ostia) were true atherosclerotic ostial lesions (true lesion group). The true lesion group had more frequent left main ostial damping and more percutaneous coronary interventions (PCIs) performed on non-ostial lesions, compared to the false lesion group. On multivariate logistic regression analysis, left main ostial damping [hazard ratio (HR) 4.11, 95% confidence interval (CI) 1.24-13.67, p=0.021] and PCI on non-ostial lesion (HR 5.34, 95% CI 1.34-21.27, p=0.018) emerged as independent predictors for true atherosclerotic ostial lesions in patients with pressure damping. CONCLUSION: Left main ostial damping and the presence of a non-ostial atherosclerotic lesion may suggest a significant true atherosclerotic lesion in the coronary ostium.

Segmental assessments of coronary plaque morphology and composition by virtual histology intravascular ultrasound and fractional flow reserve.

Fractional flow reserve (FFR) is an index for identifying functionally significant stenotic lesions. A FFR value of ≤0.75 is considered clinically significant and indicative of physiological ischemia. Focal lesions with 30-80 % stenosis by angiography with lesion lengths of less than 20 mm were selected from left anterior descending arteries of 74 patients. The analysis for the total lesion was processed first, and then each lesion was divided into three segments to assess the each segment. Data on plaque geometry and composition of two FFR groups, FFR ≤ 0.75 and FFR > 0.75, were compared by total and segmental analysis. Lesions with FFR ≤ 0.75 had more fibrofatty tissue (13.5 ± 7.4 vs. 10.2 ± 6.5%, p = 0.05) and less dense calcium (7.2 ± 5.3 vs. 11.9 ± 7.5%, p = 0.01) compared to lesions with FFR > 0.75. The content of necrotic core in mid segments was higher compared to proximal and distal segments (22.9 ± 10.6, 20.2 ± 10.9, 17.1 ± 11.2%, respectively, p = 0.032) in lesions with FFR > 0.75 but the difference was less obvious in lesions with FFR ≤ 0.75 (17.9 ± 9.9, 18.7 ± 9.9, 15.8 ± 9.0%, respectively, p = 0.533). Coronary lesions with FFR > 0.75 have larger content of dense calcium and slightly less fibrofatty tissue compared to lesions with FFR ≤ 0.75. While segmental plaque compositions for each segment show noticeable variations in lesions with FFR > 0.75 such as high concentrations of necrotic core in mid segment, these differences in each segment become obscure in FFR ≤ 0.75 and are evenly distributed across the lesion.

Combined Usefulness of the Platelet-to-Lymphocyte Ratio and the Neutrophil-to-Lymphocyte Ratio in Predicting the Long-Term Adverse Events in Patients Who Have Undergone Percutaneous Coronary Intervention with a Drug-Eluting Stent.

OBJECTIVES: The aim of this study was to investigate the combined usefulness of platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) in predicting the long-term adverse events in patients who have undergone percutaneous coronary intervention (PCI) with a drug-eluting stent (DES). METHODS: 798 patients with stable angina, unstable angina and non-ST elevated myocardial infarction (NSTEMI) who underwent elective successful PCI with DES were consecutively enrolled. The value of PLR and NLR in predicting adverse coronary artery disease (CAD) events and the correlations between these markers and adverse events (all-cause mortality, cardiac death, and nonfatal myocardial infarction) were analyzed. RESULTS: The follow-up period was 62.8 ± 28.8 months. When patients were classified into four groups according to the optimal cut-off values for the PLR and NLR on receiver operating characteristic analysis, patients with a high PLR (>128) and high NLR (>2.6) had the highest occurrence of adverse events among the groups. On Cox multivariate analysis, the NLR >2.6 [hazard ratio (HR) 2.352, 95% confidence interval (CI) 1.286 to 4.339, p = 0.006] and the PLR >128 (HR 2.372, 95% CI 1.305 to 3.191, p = 0.005) were independent predictors of long-term adverse events after adjusting for cardiovascular risk factors. Moreover, both a PLR >128 and a NLR >2.6 were the strongest predictors of adverse events (HR 2.686, 95% CI 1.452 to 4.970, p = 0.002). CONCLUSION: High pre-intervention PLR and NLR, especially when combined, are independent predictors of long-term adverse clinical outcomes such as all-cause mortality, cardiac death, and myocardial infarction in patients with unstable angina and NSTEMI who have undergone successful PCI with DES.

OCT-Defined Morphological Characteristics of Coronary Artery Spasm Sites in Vasospastic Angina.

OBJECTIVES: The aim of this study was to define the morphological features of coronary artery spasm sites using optical coherence tomography (OCT) in patients with vasospastic angina (VSA). BACKGROUND: Plaque characteristics at coronary artery spasm sites have not been investigated systematically. METHODS: Sixty-nine consecutive patients (80 spasm sites) presenting with VSA who underwent OCT imaging were included in this study. Fibrous cap disruption was identified by the discontinuation of fibrous cap with or without intraplaque cavity formation. OCT-defined erosion was established by the presence of thrombus with or without lumen irregularity overlying an intact fibrous cap on multiple adjacent OCT frames. Other morphological features such as the absence of thrombus with or without lumen irregularity and those not in the previously mentioned criteria were also documented. RESULTS: Plaque was seen on OCT in 79 of the 80 spasm sites. Fibrous cap disruption was detected at 3 sites (4%). OCT-defined erosion was observed at 21 spasm sites (26%). Thrombus with lumen irregularity was observed in 20 sites, whereas 1 site had thrombus without lumen irregularity. Lumen irregularity without thrombus was observed at 49 spasm sites (61%). Spontaneous spasm was seen more frequently in patients with acute myocardial infarction and out-of-hospital cardiac arrest than in patients without these conditions (50.0% vs. 19.3%, p = 0.025). CONCLUSIONS: Our results show that OCT-defined erosion at spasm sites occurred in more than one-fourth of patients in this study. Luminal irregularity was observed in nearly two-thirds of the patients without overlying thrombus. These findings suggest the potential role of antiplatelet therapy in VSA.

Assessment of stent edge dissections by fractional flow reserve.

BACKGROUNDS: Edge dissections after intervention have been studied with imaging techniques, however, functional assessment has not been studied yet. We investigated the relationship between fractional flow reserve (FFR) and the angiographic type of stent edge dissections and tried to assess the use of FFR-guided management for edge dissection. METHODS: 51 edge dissections assessed by FFR were included in this prospective observational study. FFR was measured for each type of edge dissection and compared with quantitative coronary angiographic findings. Clinical outcomes were evaluated based on FFR measurements. RESULTS: Edge dissections were classified as type A (47.1%; 24/51), type B (41.2%; 21/51), type C (2.0%; 1/51) and type D (9.8%; 5/51). Mean FFR in type A dissection was 0.87 ± 0.09, in type B 0.86 ± 0.07, in type C 0.72 and in type D 0.57 ± 0.08. All type C and D dissections (6/51) had FFR ≤ 0.8 and were treated with additional stents. Among the 45 type A and B dissections, 8 had a FFR ≤ 0.8 (17.8%), and 50% received additional stenting. All dissections with FFR >0.8 were left untreated except one long dissection case. There was no death, myocardial infarction or target lesion revascularization during hospitalization or the follow-up period (median 152 days; IQR 42-352 days). CONCLUSIONS: FFR correlates well with an angiographic type of edge dissection. Angiographic findings are sufficient for deciding the treatment of severe dissections such as types C and D, while FFR-guided management may be safe and effective for mild edge dissections such as types A and B.

Reproducibility of coronary artery calcium measurements using 0.8-mm-thickness 256-slice coronary CT.

PURPOSE: Coronary artery calcium (CAC) measurement has been utilized as an important indicator of coronary artery disease and predictor of cardiovascular risk. The reproducibility of CAC measurements makes it clinically useful for the assessment of progression and regression of coronary atherosclerosis. This study assessed the reproducibility of the Agatston CAC score among patients undergoing 256-slice multidetector computed tomography (MDCT) scans using 0.8-mm slice thickness. MATERIALS AND METHODS: One hundred four patients (aged 62.8 ± 9.0 years, 56.7 % males) with CAC scores >0 on 256-slice MDCT underwent additional MDCT imaging at 2-week intervals. The CAC score was quantified using the Agatston score, which was measured independently by two radiologists. RESULTS: The variability between observers and MDCT scan measurements was determined by the mean value of absolute and percentage differences: inter-scan/inter-observer (14.45 ± 21.84, 12.51 ± 21.84 %), intra-scan/intra-observer (1.75 ± 5.85, 1.26 ± 3.69 %), intra-scan/inter-observer (3.3 ± 9.1, 4.8 ± 21.3 %), and inter-scan/intra-observer (13.45 ± 20.7, 10.04 ± 10.46 %). CONCLUSION: Reproducibility in CAC measurements using the 0.8-mm-thickness 256-slice MDCT showed low inter-scan/inter-observer variability. Therefore, this CT imaging has potential to be used in prospective, longitudinal CAC assessments.