Severe Calcified Plaques Research Articles

A comparison of computed tomography imaging with histopathology in the sensitivity and correlation of evaluating coronary arterial calcification.

The sensitivity and correlation of coronary computed tomography angiography (CTA) as compared with histopathology are unknown in evaluating coronary arterial calcification. In this study, we retrospectively evaluated qualitatively and quantitatively the sensitivity and correlation of coronary CTA compared with histopathology in assessing coronary arterial calcification. This study was conducted on 12 randomly selected cadavers aged over 40 years at the time of death, and 53 segments of coronary arteries from these 12 cadavers were obtained from the Human Anatomy Laboratory of Tianjin Medical University. The artery segments were scanned using contrasted-enhanced dual-source computed tomography (DSCT) with an axial slice thickness of 0.6 mm. Coronary artery calcification in a coronary segment was defined as the presence of 1 or more voxels with a CT density >130 Hounsfield units. According to the arc of calcification in the cross section of the coronary artery wall, calcified plaques were divided into three categories: mild, moderate, and severe calcification. The coronary artery stenosis caused by calcified plaque was observed and calculated with multiplanar reconstruction (MPR), maximum density projection, volume rendering (VR), and cross-sectional reconstruction. After CT enhancement scanning, the coronary artery specimens were cut into 4-mm long segments and embedded in paraffin for pathological staining. Pathological classification and coronary artery stenosis measured with pathological analysis were used as comparison criteria. Histopathology detected 69 Vb-type plaques, while DSCT detected 57 calcified plaques. The sensitivity of CT for detecting mild, moderate, and severe calcified plaques were 88.3% [95% confidence interval (CI): 74.1-95.6%], 100% (95% CI: 69.8-100%), and 100% (95% CI: 73.2-100%), respectively. DSCT had a significant (P<0.001) correlation with histopathology in quantifying coronary artery stenosis caused by mild, moderate, and severe calcified plaques (R2=0.9278, R2=0.9158, R2=0.7923, respectively). Compared with histopathology, DSCT overestimated coronary artery stenosis caused by mild, moderate, and severe calcified plaques (3.2%±2.0%, 4.9%±4.7%, and 14.7%±8.2%, respectively; P<0.05). DSCT contrast enhancement scanning can detect and characterize coronary artery calcification with a good correlation with histopathologic quantification of coronary artery stenosis caused by different types of calcified plaques, even though coronary CTA may overestimate the stenosis.

Abstract 10824: High Bleeding Risk is Associated with a Higher Prevalence of Severe Calcified Plaque in Patients Requiring Percutaneous Coronary Intervention

Introduction: Optimal revascularization strategy and shorter duration of dual antiplatelet are required in patients with coronary artery disease concomitant with high bleeding risk (HBR). More complex percutaneous coronary intervention (PCI) and subsequent high thrombotic risk in patients with HBR have been also demonstrated. However, the characteristics of culprit plaque in patients with HBR remains to be elucidated. Hypothesis: HBR is associated with more complex plaque in culprit lesion in patients requiring PCI. Methods: A total of 362 consecutive patients with stable coronary disease, who underwent optical coherence tomography (OCT) imaging of the culprit lesion during PCI were included. The characteristics of culprit plaque assessed by OCT were compared between the HBR group (n=196) and the non-HBR group (n=166), which were classified based on the Academic Research Consortium for High Bleeding Risk (ARC-HBR). Results: The prevalence of severe calcified plaque (angle &gt;180 degee, thickness &gt;0.5mm and length &gt;5mm) was significantly higher in the higher HBR group than in the non-HBR group (48 vs. 35%, p =0.016), although other characteristics were comparable (Panel A). Among patients with HBR, the incremental prevalence of severe calcified plaque according to the number of major ARC-HBR criteria met was observed ( p &lt;0.001) (Panel B). Conclusions: HBR was associated with a higher prevalence of severe calcified plaque in culprit lesion in patients with stable coronary disease requiring PCI. The greater number of major ARC-HBR criteria met was associated with a higher prevalence of severe calcified plaque among patients with HBR.

Predicting Stroke Risk in Patients with Carotid Artery Stenosis Using Contrast Enhanced Carotid Duplex Ultrasound to Quantify Plaque Vasa-Vasorum Volume: Results of a Pilot Study

Introduction: In selecting patients for carotid revascularization, relying solely on symptoms and/or degree of stenosis is not sufficient. Patients with severe stenosis often remain asymptomatic, while other patients with moderate stenosis experience stroke. In contemporary practice, surgery or intervention is carried out much more often in asymptomatic patients. With the advent of improved medical management, the indications for surgery or intervention in the asymptomatic have become unclear. We utilized a technique for measuring Plaque Vasavasorum Volume (PVV) using Contrast Enhanced Carotid Duplex Ultrasound (CECDU) as a novel method for identifying asymptomatic patients with carotid artery stenosis who are at highest risk for stroke and thus more likely to benefit from early revascularization. Objective: To establish the diagnostic accuracy and reliability of PVV measured by CE-CDU in identifying high risk carotid plaques and to identify a diagnostic cut-off point beyond which the risk of stroke exceeds the risk of surgery/intervention in asymptomatic patients with carotid stenosis. Methods: The Stroke Prevention with Plaque Vasa-vasorum in Carotid Stenosis Study (SPIVICS) is a two phase multi-center double blinded prospective study. The first phase is a cross-sectional study of patients who qualify for carotid endarterectomy per current guidelines (asymptomatic patients with >70% stenosis and symptomatic patients with >50% stenosis). End points are analyzed using standard univariate and multivariate regression, correlation and diagnostic analyses. Outcomes: Primary outcome relating to plaque morphology is the PVV volume. Clinical outcomes are neurologic symptoms (Amaurosis fugax, transient ischemic attack, and stroke) and asymptomatic events detected on imaging. Results: A total of 16 patients were examined in this pilot study. Three were leadin subjects and four of them had severe calcified plaque and VV was not visualized. For those who had a successful screen, Mean age was 69 (± 7) years, Five males and the mean plaque VVV was 0.29 (± 0.62) mm. Conclusion: Plaque Vasa-vasorum Volume is a promising predictor of stroke risk. By identifying patients who are truly at high risk for stroke, PVV measured by CECDU will establish more reliable criteria for patient selection for intervention. This in turn will help with stroke prevention, limit disability, save lives, and expend health care resources in a more selective manner.

Complications and predictors associated with persistent hemodynamic depression after carotid artery stenting

We aimed to investigate the complications and predictors associated with persistent hemodynamic depression (PHD) after carotid artery stenting (CAS). A total of 204 patients undergoing CAS in two centers between January 2011 and November 2013 were enrolled for study into two cohorts: PHD (systolic blood pressure <90mm Hg and heart beat rate <60/min, which lasted more than 1h) and non-PHD according to their periprocedure detections. The complications were recorded and compared between the two groups. The predictors of PHD were analyzed by univariate analysis and logistic regression model. 43 patients developed PHD, which lasted for 17.22h on average. The complications occurred in 9 patients of PHD group (angina pectoris 2, myocardial infarction 1, cerebral infarction 3, transient ischemic attack 2 and intestinal obstruction 1), which was significantly more than non- PHD group (angina pectoris 1, cerebral infarction 1, transient ischemic attack 5, p=0.001). Regression analysis revealed that diabetes, severe calcified plaque and a balloon dilation pressure of more than 8 atmospheres (atm) were the independent predictors for PHD after CAS. We concluded that PHD may be related to increased complications of CAS. Patients with diabetes, more severe calcified plaque and more balloon dilation pressure are more prone to develop PHD after CAS.

CORONARY ARTERY PLAQUES IN MAINTENANCE DIALYSIS PATIENTS: HISTOPATHOLOGICAL FEATURES AND EX VIVO OPTICAL COHERENCE TOMOGRAPHY IMAGING

It is well known that coronary artery (CA) in maintenance dialysis patients demonstrates diffuse stenosis and severe calcified plaques. Recently, diabetic nephropathy is a major course of hemodialysis. Although previous study indicated medial calcification of muscular arteries in these patients,

Risk factors associated with haemodynamic depression during and after carotid artery stenting

We aimed to investigate the risk factors for haemodynamic depression (HD) during and after carotid artery stenting (CAS). A total of 251 patients with CAS, enrolled between June 2004 and December 2008, were divided into two groups according to periprocedure observations: (i) a group with HD (systolic blood pressure < 90 mmHg and heart beat rate < 50/ beats per minute); and (ii) a group without (non-HD). The risk factors for HD were analysed by univariate analysis and a logistic regression model. The univariate analysis of variance showed that the following factors were significantly associated with HD in patients with CAS: severe calcified plaque, stenosis greater than 70%, distance from the carotid bifurcation to the maximum stenotic lesion of <10 mm, balloon dilation lasting more than 5 s with a pressure of more than 8 atmospheres (atm), multiple balloon dilations, balloon length, balloon diameter, and bilateral stenting. The results of the logistic regression model analysis showed that the following were independent risk factors for HD during and after CAS: the degree of stenosis, severe calcified plaque, bilateral stenting and a balloon dilation pressure of >8 atm. We concluded that patients with stenosis > 70%, severe calcified plaque, bilateral stenting and a balloon dilation pressure > 8 atm may be more likely to develop HD during and after CAS.

Noninvasive Coronary Angiography

WHEN SONES INADVERTENTLY PERFORMED THE first coronary angiogram in 1958, he could not anticipate the profound future implications of that event. Four years later, when he reported his experience with more than 1000 procedures, the technique was still considered experimental and was dismissed by many leading authorities in cardiovascular medicine. Yet, the introduction of coronary angiography started a new era, leading to the rapid development of coronary artery bypass graft surgery and percutaneous revascularization for the routine management of ischemic heart disease. Four decades later, more than 2 million angiographic procedures are performed annually in the United States alone. Although invasive coronary angiography clearly has led to improved outcomes, it also has contributed to greater expenses in health care cost, limiting its potential to become more widely available. This has led to a growing interest in the scientific community in the development of less expensive, noninvasive alternative methods for evaluating coronary anatomy. Multislice computed tomography (MSCT) has recently emerged above other competing technologies, such as electron-beam computed tomography and magnetic resonance imaging, as a practical alternative to invasive coronary angiography. Modern MSCT systems can provide electrocardiogram-gated acquisition with adequate temporal resolution (100-220 ms) and with the submillimeter spatial resolution needed to visualize with sufficient detail the lumen of the coronary arteries. Several studies have investigated the accuracy of MSCT in patients with known or suspected coronary artery disease (CAD). In these studies, analysis ofMSCThasbeenmostly limited tocoronary segmentsgreater than or equal to 1.5 or 2 mm in diameter, and up to 5% to 20% of all analyzable segments have been deemed nonevaluable due to motion artifacts, severe calcified plaques, and other technical imaging problems. The sensitivity and specificity of MSCT for detecting a 50% or greater diameter reduction in coronary segments has ranged between 72% and 95% and between 85% and 100%, respectively. Many of the published series have enrolled nonconsecutive patients, and only a few have reported the performance characteristics of MSCT using each patient as the unit of analysis. In this issue of JAMA, Hoffmann and colleagues evaluated the diagnostic accuracy of MSCT for the detection of obstructive CAD. Their study includes a large series of nonselected patients in whom very few (6.4%) coronary segments larger than 1.5 mm in diameter were excluded from analysis due to limited image quality. The majority (68%) of these excluded segments were considered nonevaluable due to imaging artifacts related to cardiac motion, most often in patients with resting heart rates greater than 80/min. Motion artifacts still represent an important limitation of current MSCT technology, even though most investigators now routinely administer -blockers to reduce resting heart rate. Extensive vessel calcifications also limit the interpretation of luminal stenosis by MSCT, often leading to overestimation of severity. These accounted for many of the falsepositive results observed by Hoffmann et al. Despite these limitations, their reported per-segment sensitivity (95%) and specificity (98%) are noteworthy, particularly when these performance characteristics are compared with those of other indirect methods used for the detection of obstructive CAD, such as nuclear scintigraphy or echocardiographic stress tests. The authors also report diagnostic characteristics according to a per-patient–based analysis. This is critically important, since the implications of detecting or missing the presence or absence of any significant coronary obstruction are more clinically relevant from the perspective of the individual patient. Even after accounting for nonevaluable segments, the high positive (90%) and negative (95%) predictive values strongly support the conclusion that, in this patient population, MSCT is a robust test for establishing the diagnosis of obstructive CAD. In addition to the conventional binomial analysis, the authors performed a quantitative comparison of percentage luminal stenosis as determined by MSCT and invasive angiography. Receiver operating characteristic curves were constructed to estimate discriminative power for identifying patients who might be candidates for revascularization. The area under the curve was 0.97 (95% confidence interval, 0.91-1.00) for detecting greater than 50% left main artery disease, greater than