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Intraprocedural stent thrombosis (IPST) is a rare complication of percutaneous coronary intervention that leads to poor outcomes; however, the factors contributing to IPST remain largely unknown. Accordingly, we used intravascular ultrasound (IVUS) to examine the lesion characteristics in patients with IPST. We retrospectively analyzed 1,504 consecutive stent-implanted lesions in 1,324 patients (326 with ST-segment elevation myocardial infarction [STEMI], 403 patients with non-ST-segment elevation acute coronary syndrome [NSTE-ACS], and 595 patients with stable angina). Of these, IPST occurred in 5 patients during percutaneous coronary intervention (0.4% per patient; 3 with STEMI, 2 with NSTE-ACS). The IVUS characteristics of plaques that developed IPST were compared with those of controls without the evidence of IPST (non-IPST; n = 15) who were matched by age, gender, lesion location, and clinical presentation (STEMI, NSTE-ACS, or stable angina). All 5 lesions that led to IPST had ruptured plaques with positive remodeling and attenuation. Plaque rupture was also observed in 40% of the non-IPST group. Multiple plaque ruptures in the culprit lesion were more common in the IPST group (80% vs 7%; p <0.01). The maximum cavity area was larger in the IPST group than in the non-IPST group having plaque rupture (4.6 mm(2) [interquartile range, 4.3 to 6.5] vs 2.4 mm(2) [1.8 to 2.9]; p <0.01). In conclusion, we found using IVUS that multiple plaque ruptures with larger cavities more often evolved into IPST. [ABSTRACT FROM AUTHOR]

Previous studies have suggested that angiographically detected peristent contrast staining (PSS) at follow-up may predict subsequent very late stent thrombosis. The Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS- AMI) trial was a dual-arm, factorial, randomized trial in patients with ST-segment elevation myocardial infarctions. All follow-up angiograms (1,330 lesions in 1,115 patients, median time 13.3 months) without major cardiovascular events before follow-up angiography were analyzed at a core laboratory blinded to clinical events for the presence of PSS (defined as contrast staining outside the stent contour extending to ≥20% of the stent diameter). Corresponding follow-up intravascular ultrasound (IVUS) data (275 lesions in 248 patients) were also evaluated to assess the mechanisms of PSS. PSS was present in 23 patients (2.1%) at follow-up and was not more common with paclitaxel-eluting than with bare-metal stents. All 6 PSS patients with follow-up IVUS had stent malapposition (vs 41.2% malapposition in the follow-up IVUS cohort). Comparing poststent and follow-up IVUS, 2 patients had late acquired and 4 had persistent malapposition; all 6 showed positive vessel remodeling from baseline to follow-up (mean vessel area 22.0 ± 8.0 to 32.4 ± 11.7 mm², p = 0.07). During 3-year follow-up, stent thrombosis developed in no patient with PSS compared with 8 PSS-negative patients (0% vs 0.8%, p = 0.68). The rates of revascularization and major adverse cardiovascular events were also not increased in PSS patients. In conclusion, in the large-scale HORIZONS-AMI trial, PSS at angiographic follow-up was infrequent and was associated with late stent malapposition and positive remodeling but was independent of stent type. Identification of PSS was not associated with subsequent stent thrombosis. [ABSTRACT FROM AUTHOR]

Abstract: We evaluated the relationship between coronary calcification and plaque characteristics using integrated backscatter-intravascular ultrasound (IB-IVUS), focusing on spotty calcification. Seventy-two patients with culprit plaques containing spotty calcification were evaluated. The average degree of all the spotty calcifications (averaged arc) negatively correlated with the % lipid volume (LV) on IB-IVUS. Multivariate analysis showed the averaged arc was an independent predictor of % LV. Our observations suggest that smaller plaque calcifications are associated with lipid-rich characteristics in patients with a spotty calcification pattern. [ABSTRACT FROM AUTHOR]

We evaluated the feasibility of myocardial perfusion ratio to the aorta (MPR) in static computed tomography perfusion (CTP) for detecting myocardial perfusion abnormalities assessed by single-photon emission computed tomography (SPECT). Twenty-five patients with suspected coronary artery disease who underwent dynamic CTP and SPECT were retrospectively evaluated. CTP images scanned at a sub-optimal phase for detecting myocardial perfusion abnormalities were selected from dynamic CTP images and used as static CTP images in the present study. The diagnostic accuracy of MPR derived from static CTP was compared to those of visual assessment and conventional quantitative parameters such as myocardial CT attenuation (HU) and transmural perfusion ratio (TPR). The area under the curve of MPR (0.84; 95% confidence interval [CI], 0.76–0.90) was significantly higher than those of myocardial CT attenuation (0.73; 95% CI, 0.65–0.79) and TPR (0.76; 95% CI, 0.67–0.83) (p < 0.05). Sensitivity and specificity were 67% (95% CI, 54–77%) and 90% (95% CI, 86–92%) for visual assessment, 51% (95% CI, 39–63%) and 86% (95% CI, 82–89%) for myocardial CT attenuation, 63% (95% CI, 51–74%) and 84% (95% CI, 80–88%) for TPR, and 78% (95% CI, 66–86%) and 84% (95% CI, 80–88%) for MPR, respectively. MPR showed higher diagnostic accuracy for detecting myocardial perfusion abnormality compared with myocardial CT attenuation and TPR. [ABSTRACT FROM AUTHOR]

Abstract: Background: The aim of this study was to investigate the significance of the MOSAIC (measurement of stenosis by aliasing coronary flow) method for the detection of proximal left coronary stenosis in patients with unstable angina (UA) using transthoracic Doppler echocardiography (TTDE). Methods: Patients (n = 107) with UA were evaluated. Proximal left coronary flow was sought in the short axis (SAX) at the aortic root level using color Doppler guidance. When detected coronary flow showed color aliasing, the color velocity range was gradually increased until color aliasing nearly disappeared. Then, the color baseline was shifted until the color flow showed “isovelocity”. Results: Proximal coronary flow was detected in 86 (80.4%) of 107 patients. In these 86 patients, an optimal cutoff value of isovelocity≥47.5cm/s predicted significant coronary stenosis (percent diameter stenosis≥70%) of the proximal left anterior descending (AHA segment 6) or left main coronary artery with a sensitivity of 88%, specificity of 97%, positive predictive value of 98%, and negative predictive value of 86%. In all 107 patients, the same cutoff value predicted significant coronary stenosis with a sensitivity of 78%, specificity of 98%, positive predictive value of 98%, and negative predictive value of 81%. Conclusions: The MOSAIC method may play a complementary role in expeditious risk stratification and decision making in patients with UA. [Copyright &y& Elsevier]

Abstract: Background: The aim of this study was to investigate the differences in left ventricular (LV) twisting behavior between patients with hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD). Methods: Forty-four patients with HCM (mean age, 63±15years), 35 patients with HHD (mean age, 63±13years) and 20 age and sex-matched control subjects were evaluated. After a standard echocardiographic examination, LV twist and twisting velocity profiles from apical and basal short-axis images were analyzed using two-dimensional speckle tracking imaging. Results: LV diastolic and systolic dimensions, and ejection fraction were not significantly different among the groups. LV mass index and early diastolic mitral annular velocity were not significantly different between the HCM and HHD groups. The peak torsion in the HCM and HHD groups was significantly greater than that in the control group. The peak untwisting velocity in the HCM group was comparable with that in the control group. However, when the peak untwisting velocity was corrected by peak torsion, this ratio was significantly decreased in the HCM group compared with the values in the HHD and control groups. The time to peak untwisting velocity in the HCM group was significantly longer than the values in the HHD and control groups. Conclusions: These results suggest that enhanced peak torsion in HCM may improve untwisting behavior, but this mechanism fails to fully compensate for impaired untwisting behavior compared with HHD. [Copyright &y& Elsevier]

We examined the effects of cilostazol on impaired coronary arterial responses in patients with vasospastic angina (VSA). Thirty patients who were diagnosed with VSA based on an acetylcholine provocation test and 10 subjects with normal coronary arteries were enrolled. The patients were divided into the following 3 groups: no antiplatelet agent treatment group, aspirin treatment, or cilostazol treatment groups. Coronary flow reserve (CFR), coronary flow volume at maximum hyperemia, and epicardial coronary artery diameter after administration of N(G)-monomethyl-L-arginine (L-NMMA) were examined using a Doppler flow wire before and 6 months after the start of this study. CFR, coronary flow volume at maximum hyperemia, and diameter changes by L-NMMA were significantly increased in the cilostazol treatment group compared with the other 2 groups. In conclusion, cilostazol increased CFR and flow-dependent coronary dilation; these changes were attributable to nitric oxide. Cilostazol may improve coronary vascular endothelial dysfunction and coronary hemodynamics in patients with VSA. [ABSTRACT FROM AUTHOR]

We examined the effects of cilostazol on impaired coronary arterial responses in patients with vasospastic angina (VSA). Thirty patients who were diagnosed with VSA based on an acetylcholine provocation test and 10 subjects with normal coronary arteries were enrolled. The patients were divided into the following 3 groups: no antiplatelet agent treatment group, aspirin treatment, or cilostazol treatment groups. Coronary flow reserve (CFR), coronary flow volume at maximum hyperemia, and epicardial coronary artery diameter after administration of NG-monomethyl-l-arginine (l-NMMA) were examined using a Doppler flow wire before and 6 months after the start of this study. CFR, coronary flow volume at maximum hyperemia, and diameter changes by l-NMMA were significantly increased in the cilostazol treatment group compared with the other 2 groups. In conclusion, cilostazol increased CFR and flow-dependent coronary dilation; these changes were attributable to nitric oxide. Cilostazol may improve coronary vascular endothelial dysfunction and coronary hemodynamics in patients with VSA. [Copyright &y& Elsevier]