Collaterals In Patients Research Articles

The association between left ventricular mass index and coronary collateral circulation in patients with chronic total occlusion.

Left ventricular (LV) hypertrophy predisposes the myocardium to ischemia through several mechanisms. The LV mass index (LVMI) is used as a readily available and reliable measurement of LV hypertrophy. The LVMI can also be used to evaluate LV remodeling. The hypothesis of this study was that LV hypertrophy might augment coronary collateralization in patients with chronic total occlusion (CTO) and the aim was to research any association between LVMI and collateral formation in CTO. As a secondary goal, specific LV geometric types that might be associated with collateral presence were also investigated. A total of 305 patients with CTO were included and categorized into 4 groups based on Rentrop grade. The LVMI demonstrated an incremental linear trend as the Rentrop grade increased. In the receiver operating characteristic curve, the likelihood that a cut-off value of 100.1 g/m2 would accurately differentiate patients with collaterals from those without collaterals was 75.8%, with 68.5% sensitivity and 68.6% specificity. A 1 gram/m2 increase in LVMI was associated with a 7.5% greater likelihood of collateral development. In addition, compared with normal geometry, the presence of eccentric hypertrophy was associated with 6.7 times higher odds of the presence of coronary collaterals. The results of this study indicated that a greater LVMI predicted coronary collateral presence. Furthermore, having an eccentric geometric type of hypertrophy increased the likelihood of coronary collaterals more than other geometries. This finding signified that in addition to LV wall thickness, the type of hypertrophy was also decisive in predicting collateral presence.

The influence of plasma 25-(OH) vitamin D levels in acute ST elevation myocardial infarction.

The preventive role of acute occurring of collateral circulation (AOCC) to infarct related artery (IRA) in patients presenting with acute ST-segment elevation myocardial infarction (STEMI) is well known. Therefore, we aimed to investigate whether there is an association between admission plasma 25-hydroxyvitamin D (25(OH)D3) levels and grade of collateralization in patients with STEMI. We prospectively included 369 STEMI patients within the first 12 h of symptoms onset. Patients were divided into two groups according to their Rentrop collateralization grade to IRA: poorly developed collateral (PDC) group (Rentrop grade ≤ 1, 272 patients) and well developed collateral (WDC) group (Rentrop grade ≥ 2, 97 patients). We observed that AOCC grade to IRA was negatively correlated with high sensitive C-reactive protein (hs-CRP), N terminal pro-B-type natriuretic peptide (NT-proBNP), as well as peak troponin T levels, yet positively correlated with admission plasma 25(OH)D3 level (p < 0.05, for all). In multi¬variate analysis, 25(OH)D3 levels (OR 1.246, 95% CI 1.185-1.310, p < 0.001), together with hs-CRP, NT-proBNP, and peak troponin T levels were found independent predictors of AOCC to IRA in patients with acute STEMI. Admission level of plasma 25(OH)D3 levels together with cardiac risk biomarkers (troponin T, NT-proBNP, hs-CRP) are associated with collateralization grade to IRA in acute STEMI patients. In addition, 25(OH)D3 may be a promoter of AOCC in patients with acute STEMI.

MR Perfusion to Determine the Status of Collaterals in Patients with Acute Ischemic Stroke: A Look Beyond Time Maps.

Patients with acute stroke with robust collateral flow have better clinical outcomes and may benefit from endovascular treatment throughout an extended time window. Using a multiparametric approach, we aimed to identify MR perfusion parameters that can represent the extent of collaterals, approximating DSA. Patients with anterior circulation proximal arterial occlusion who had baseline MR perfusion and DSA were evaluated. The volume of arterial tissue delay (ATD) at thresholds of 2-6 seconds (ATD2-6 seconds) and >6 seconds (ATD>6 seconds) in addition to corresponding values of normalized CBV and CBF was calculated using VOI analysis. The association of MR perfusion parameters and the status of collaterals on DSA were assessed by multivariate analyses. Receiver operating characteristic analysis was performed. Of 108 patients reviewed, 39 met our inclusion criteria. On DSA, 22/39 (56%) patients had good collaterals. Patients with good collaterals had significantly smaller baseline and final infarct volumes, smaller volumes of severe hypoperfusion (ATD>6 seconds), larger volumes of moderate hypoperfusion (ATD2-6 seconds), and higher relative CBF and relative CBV values than patients with insufficient collaterals. Combining the 2 parameters into a Perfusion Collateral Index (volume of ATD2-6 seconds × relative CBV2-6 seconds) yielded the highest accuracy for predicting collateral status: At a threshold of 61.7, this index identified 15/17 (88%) patients with insufficient collaterals and 22/22 (100%) patients with good collaterals, for an overall accuracy of 94.1%. The Perfusion Collateral Index can predict the baseline collateral status with 94% diagnostic accuracy compared with DSA.

Prognostic value of coronary collaterals in patients with acute coronary syndromes.

The presence of good coronary collateral circulation (CCC) can protect and preserve myocardium from ischemia, increase myocardial contractility, and reduce adverse clinical events. However, its impact on mortality is still a topic of debate, particularly in acute coronary syndrome (ACS). The aim of this study was to investigate the association of CCC with cardiac risk factors and in-hospital mortality in patients hospitalized with a diagnosis of ACS. The study population included 2286 patients with ACS who underwent coronary angiography and were found to have at least 90% significant lesion in at least one major coronary artery. The CCC was graded according to the Rentrop classification. The patients were classified into a poor CCC group (Rentrop grades 0-1, n=1859) or a good CCC group (Rentrop grades 2-3, n=427). Patients with good CCC had more high-risk patient characteristics such as older age, higher rate of Killip class of at least 2 at admission, lower left ventricular ejection fraction, and impaired renal functions compared with the patients with poor CCC. In multivariate analysis, the presence of good CCC [odds ratio (OR): 2.000; 95% confidence interval: 1.116-3.585; P=0.020], left ventricular ejection fraction less than 40% (OR: 2.381; P=0.003), Killip class of at least 2 at admission (OR: 3.609; P<0.001), age of at least 65 years (OR: 2.975; P=0.003), and hemoglobin (OR: 0.797; P=0.003) were independent predictors of in-hospital mortality. In contrast to previous studies, our study did not confirm a beneficial role of good CCC in patients with ACS; the presence of good CCC was even independently associated with increased in-hospital mortality in the multivariate analysis.

P1753Impact of lipoprotein (a) interactions with low-density lipoprotein cholesterol on coronary collateralization in patients with stable coronary artery disease and chronic total occlusion

P1753Impact of lipoprotein (a) interactions with low-density lipoprotein cholesterol on coronary collateralization in patients with stable coronary artery disease and chronic total occlusion

Twenty years of experience with intraoperative pulmonary artery stenting.

To describe our 20-year experience with intraoperative pulmonary artery (PA) stent placement and evaluate long-term patient outcomes, specifically the need and risk factors for reintervention. Intraoperative PA stent placement is an alternative to surgical patch arterioplasty and percutaneous angioplasty or stent placement to treat branch PA stenosis. We performed a retrospective review of all intraoperative PA stents placed at our institution from 1994-2013. Patient and stent characteristics and outcome data were collected. Risk factors associated with reintervention were identified using univariate cox regression analysis. Eighty-one PA stents were placed in 68 patients. The procedural complication rate was 4.4%. During a median follow-up period of 6 years (interquartile range [IQR] 0.9-12.7), 30 patients (44%) underwent reintervention on the stented PA with a median time to first reintervention of 2.6 years (IQR 0.7-4.4 years). The first reintervention was surgical in 30% and catheter-based in 70%. Risk factors for reintervention included age < 18 months (Hazard ratio [HR] 2.97, P = 0.005) and body surface area < 0.47 m2 (HR 3.20, P = 0.003) at the time of stent implantation, and the presence of multiple aortopulmonary collaterals in patients with tetralogy of Fallot (HR 4.61, P = 0.003). Intraoperative PA stent implantation is a safe and effective alternative to percutaneous stent implantation and offers several advantages, including the ability to implant adult-size stents in small patients while avoiding injury to peripheral vessels, to position stents to facilitate future percutaneous stent redilation, and to access the PAs directly, which eliminates radiation exposure. © 2017 Wiley Periodicals, Inc.

Abstract WMP22: Multiparametric CT Perfusion to Determine the Collaterals Status in Patients With Acute Ischemic Stroke: A New Perfusion Index

Introduction: Good collateral flow is an independent predictor of reperfusion that can be used to extend the treatment window in the new era of endovascular therapies for patients with acute ischemic stroke (AIS). Using a multiparametric approach, we aimed to identify perfusion parameter/s that can represent the extent of collaterals in comparison to CTA. Methods: AIS patients with anterior circulation large vessel occlusion who had baseline CTA and CT perfusion were included. CT perfusion data were processed by Bayesian method to generate arterial tissue delay (ATD) maps at thresholds of 2 &amp; 6 seconds. The volume of mild delayed perfusion (Vol-ATD &gt;2sec ), moderate delayed (Vol-ATD 2-6sec ) and critical delayed perfusion (Vol-ATD &gt;6sec ) in addition to corresponding rCBV and rCBF were calculated. Baseline CTA collaterals were scored using an established scoring scale1 and dichotomized to poor or good. The association of perfusion parameters and status of collaterals was assessed by repeated measure of analyses and receiver operating characteristic (ROC). Results: In 28 patients included, 16 had good collaterals on CTA. After controlling for age, sex, baseline NIHSS and type of treatment, multivariate logistic regression analysis identified rCBV (p&lt;0.001) and ATD 2-6sec (p=0.003), but not rCBF, Vol-ATD &gt; 2sec or Vol-ATD &gt;6sec , as independent predictors of good collaterals. ROC analysis showed AUC of 0.88 (sensitivity/specificity: 75%/100%) for rCBV and AUC of 0.84 (sensitivity/specificity: 93%/67%) for Vol-ATD 2-6sec . We defined a perfusion collateral index (PCI) calculated from Vol-ATD 2-6sec x its rCBV, that remained an independent predictor of good collaterals with improved diagnostic accuracy over each measure alone resulting in nominal AUC of 1 (sensitivity/specificity: 100%/100%). Conclusions: Multiparametric CT perfusion can be used to assess the status of collaterals in patients with AIS. Perfusion collateral index (PCI) defined as Vol-ATD 2-6sec x rCBV is a new perfusion index with a nominal diagnostic accuracy of 100% compared to baseline CTA to predict status of collaterals in our small cohort. Our results need to be validated in a larger prospective cohort.

Abstract WMP23: Enhanced Collaterals in Patients with Large Vessel Stroke from Intracranial Atherosclerosis: An Automated CT Perfusion-based Study

Background and Purpose: Patients with intracranial atherosclerotic disease (ICAD) are believed to have enhanced collateral flow. We have anecdotally perceived that large vessel occlusion acute strokes (LVOS) patients due to ICAD have more benign automated CT perfusion (CTP) defect profiles, potentially reflecting improved collateralization in comparison to embolic LVOS. Methods: Retrospective review of a prospectively collected interventional stroke database from Sep 2010-Mar 2015. Patients were dichotomized into ICAD vs. other etiology. Patients with a technically adequate CTP and an intracranial ICA, MCA M1 or M2 occlusion were included. Tandem extracranial carotid occlusions were excluded due to the known effects on bolus dispersion and delay of bolus passage. Ischemic core (relative CBF&lt;30%) and perfusion defects were estimated by RAPID automated CTP. The primary endpoint was to compare the ratio of CTP Tmax&gt;4s (“benign oligemia”) / Tmax&gt;6s (“territory at risk”) between the two groups. Results: A total of 250 patients fit inclusion criteria, of whom 21 (8%) were classified as ICAD and 229 had other stroke etiologie. Baseline characteristics were similar between the two groups, except for higher hemoglobin A1c levels (p&lt;0.01), higher baseline systolic blood pressure (p&lt;0.01); and lower rates of atrial fibrillation (p&lt;0.01) in the ICAD group. There were no differences in ischemic core (p=0.51), perfusion defect Tmax&gt;4s (p=0.86), Tmax&gt;6s (p=0.57) and Tmax&gt;10s (p=0.17). ICAD patients had a median ratio of Tmax&gt;4s/ Tmax&gt;6s of 2. A Tmax&gt;4s/ Tmax&gt;6s ratio≥2 showed a specificity of 83% and a sensitivity of 52%, and was more common in the ICAD group (p=0.1). Multivariate logistic regression analysis revealed that higher rates of Tmax&gt;4s/ Tmax&gt;6s ratio≥2 (OR 3.36 95% CI 1.05-10.71, p=0.04), lower rates of atrial fibrillation(OR 0.17 95% CI 0.04-0.86, p=0.03), and higher systolic pressure (OR 1.03 95% CI 1.01-1.05, p=0.002) were independently associated with ICAD. Conclusion: A RAPID CTP Tmax&gt;4s/ Tmax&gt;6s ratio≥2 profile is an independent and highly specific indicator of underlying ICAD LVOS etiology.

Ophthalmic Artery Flow and Cognitive Performance in Patients with Carotid Artery Stenosis

The circle of Willis is regarded as the primary collaterals in patients with severe carotid artery stenosis (CAS), while the secondary collaterals from the reversed ophthalmic artery (OA) flow would be recruited when the primary collaterals are inadequate to maintain cerebral perfusion. Even though some reports suggest patients with reversed OA flow are more vulnerable to cerebral ischemic injury, whether reversed OA flow is adequate to maintain cognitive function or can be employed as a surrogate marker of cognitive impairment remains elusive. The purpose of this article is to review the dynamic behavior of collateral flow and to assess the relationship between OA hemodynamics, cerebral perfusion and cognitive performance in patients with CAS. There is evidence that the OA flow patterns behave dynamically according to the hemodynamic, metabolic, and neural demands. Patients with reversed OA flow have compensatory increased cerebral blood volume and timerelated perfusion parameters, while cerebral blood flow usually remains unchanged. Despite of the evidence having been scarce, the associations between hemodynamics of OA flow and cognitive performance have been observed in several recent studies. Furthermore, our previous study demonstrated a tendency for specific cognitive impairment observed in patients with reversed OA flow, depending on the side of reversed OA flow. However, the impacts of the OA flow patterns on cognition may be modified when the other pathogenic factors of stroke are taken into account. Concurrent application of multimodality neuroimaging findings about perfusion status and neural activities will greatly enhance our understanding of the relationships between the hemodynamics of OA flow and cognition.

Association of CXCR4 expression with coronary collateralization in patients with chronic total coronary occlusion: A nested case–control study

ObjectiveCXCR4 signaling contributes to the development and progression of neovascularization. The objective of this study was to investigate whether CXCR4 expression in peripheral CD34+ cells associated with the coronary collateralization (CC) in patients with chronic total coronary occlusion (CTO). Methods and resultsWe measured CXCR4 expression in peripheral CD34+ cells and assessed its relation with CC in a nested case–control study including 78 cases and 78 matched controls aged 38–69years, assessed in January 2011 to December 2012 and with at least 1year of follow-up before the index date. Cases were defined as good coronary collateralization (GCC) according to the Rentrop scoring system (Rentrop score of 2 or 3); for each case, one age-matched control with poor coronary collateralization (PCC) (Rentrop score 0 or 1) was randomly selected from the study participants. Demographic, biochemical, and angiographic variables were collected. In multivariate analysis, the OR (95% CI) of CXCR4 expression was 0.018 (0.017 to 0.020) in patients with GCC versus PCC. Independent effect of CXCR4 expression on CC was (OR 0.012, 95% CI 0.010–0.014) when adjusted for other variables. A nonlinear relationship between CXCR4 expression and CC was observed. The CC degree increased when CXCR4 expression exceeded the turning point (30%) (OR 0.025, 95% CI 0.022–0.028; p<0.001). When the CXCR4 expression exceeded 75%, increased CXCR4 level could not promoted CC (OR 0.000, 95% CI 0.008–0.007; p=0.974). ConclusionIncreased CXCR4 level in peripheral CD34+ cells was associated with GCC in patients with CTO.

Relation Between C-X-C Motif Chemokine Receptor 4 Levels and the Presence and Extent of Angiographic Coronary Collaterals in Patients With Chronic Total Coronary Occlusion

Coronary collateral circulation is an alternative source of blood supply to the myocardium in the presence of chronic total coronary occlusion (CTO). C-X-C motif chemokine receptor 4 (CXCR4) signaling usually contributes to neovascularization. Here, we investigate the relation between CXCR4 levels in peripheral blood CD34+ cells and the formation of angiographic coronary collaterals and determine the risk factors that affect CXCR4 expression in patients with CTO. Demographic, biochemical, and angiographic variables were collected from 324 patients with CTO and 90 negative controls. The presence and extent of collaterals were scored according to the Rentrop scoring system (Rentrop's). CXCR4 levels and plasma biochemical factors were detected. Clinical outcomes were collected during a 12-month follow-up. Results show that low (Rentrop's 0 or 1) and high (Rentrop's of 2 or 3) coronary collateralizations were detected in 183 and 141 patients, respectively. The Rentrop scores were positively correlated with CXCR4 levels in patients with CTO. Patients with low CXCR4 expression exhibited worse clinical outcomes compared with those with high CXCR4 expression. Univariate correlation analysis revealed that age of ≥65years, women, diabetes, increased plasma level of high-sensitivity C-reactive protein (hs-CRP), and N-terminal brain-type natriuretic peptide were associated with low CXCR4 levels. In conclusion, CXCR4 levels were positively correlated with the presence and extent of angiographic coronary collaterals in patients with CTO. Elder age, women, diabetes, increased plasma level of high-sensitivity C-reactive protein, and N-terminal brain-type natriuretic peptide may be risk factors of CXCR4 expression.

Association of serum mimecan with angiographic coronary collateralization in patients with stable coronary artery disease and chronic total occlusion

Background and aimsMimecan/osteoglycin is identified as an emerging biomarker of coronary atherosclerosis. We investigated whether and to what extent serum mimecan reflects angiographic coronary collateralization in patients with stable coronary artery disease and chronic total occlusion. MethodsSerum levels of mimecan were determined in 559 consecutive patients with stable angina and angiographic total occlusion of at least one major coronary artery. The degree of collaterals supplying the distal aspect of a total occlusion from the contra-lateral vessel was graded as poor (Rentrop score of 0 or 1) or good coronary collateralization (Rentrop score of 2 or 3). ResultsSerum mimecan was significantly higher in patients with poor collateralization than in those with good collateralization, and correlated inversely with Rentrop score (adjusted Spearmen's r = −0.443, p < 0.001). The prevalence of poor coronary collaterals increased stepwise from the lowest to the highest quartile of serum mimecan (OR 2.140, 95% CI 1.793–2.555; p for trend < 0.001). After adjusting for age, gender, traditional risk factors for coronary artery disease, history of myocardial infarction, severity of coronary artery disease, renal function and C-reactive protein, serum mimecan (per SD) remained an independent determinant for poor collateralization (OR 2.674, 95% CI 2.057–3.475, p < 0.001). The diagnostic value of mimecan (per SD) for detecting poor collateralization was consistent when the patients were specified by gender, age, body mass index, presence or absence of hypertension and diabetes, and status of renal function (OR 2.075–6.932, p interaction ≥ 0.059). ConclusionIncreased serum mimecan is associated with poor angiographic coronary collateralization in patients with chronic total occlusion.

Prevalence of Coronary Artery to Pulmonary Artery Collaterals in Patients with Chronic Thromboembolic Pulmonary Hypertension: Retrospective Analysis from a Single Center.

Our aim was to determine the prevalence of coronary artery - pulmonary artery collaterals in patients with chronic thromboembolic pulmonary hypertension (CTEPH) by retrospectively evaluating coronary angiograms of eligible consecutive patients who had undergone pulmonary endarterectomy (PEA). We also aimed to evaluate predictors and potential clinical associates of these collaterals. Coronary angiograms of 83 consecutive CTEPH patients who had undergone coronary angiography before PEA operation between January 1, 2012 and June 1, 2015 were retrospectively evaluated for presence of coronary artery - pulmonary artery collaterals. Medical records of all patients were also retrospectively reviewed for demographic information, cardiovascular risk factors, preoperative right heart catheterization reports, operation reports, and follow-up data. Data of CTEPH patients with coronary artery - pulmonary artery collaterals were compared with data of CTEPH patients without such collaterals. There were 15 patients (18.1%) with definite and 4 patients (4.8%) with probable coronary artery - pulmonary artery collaterals among the study population. CTEPH patients with collaterals had higher preoperative pulmonary artery pressures, higher pulmonary vascular resistance (PVR) and lower cardiac index values compared with CTEPH patients without collaterals. However, CTEPH patients with collaterals displayed higher amount of reduction in PVR after PEA compared with patients without collaterals. There were no significant differences between groups regarding incidence of reperfusion injury or mortality. Prevalence of coronary artery - pulmonary artery collaterals seems to be increased in our CTEPH patients compared with the general population. The presence of coronary artery - pulmonary artery collaterals is often combined with proximal disease with the possibility of increased reduction of PVR after PEA operation.

Plasma endothelin-1 level as a predictor for poor collaterals in patients with ≥ 95% coronary chronic occlusion

BackgroundCoronary collateral circulation (CCC) plays an important role in protecting myocardium from ischemic damage. The studies on factors which impact on CCC might be of great clinical interest. The aim of the present study was to evaluate endothelin-1 (ET-1) as a potential predictor for poor or good CCC in patients with angiography-proven ≥95% coronary occlusion. MethodsWe screened 1038 consecutive patients with ≥95% occlusion in at least one major epicardial coronary artery detected by coronary angiography. Of these, 663 patients were classified into the poor CCC group with Rentrop 0–2 grade collateral circulation and 375 patients into the good CCC group with Rentrop 3 grade. The association of plasma ET-1 levels with collateral status was assessed. ResultsWe found that patients in the poor CCC group had a higher ET-1 level than those in the good CCC group (0.59±0.48 vs. 0.39±0.32pmol/L, p<0.001), and the ET-1 values increased with the descent of the Rentrop grades (p for trend<0.001). Moreover, multivariate logistic regression analysis revealed an independent association between ET-1 and collateral status (odds ratio [95% CI] for poor CCC 2.27 [1.60–3.22], p<0.001). Additionally, the association presented significance in both men (odds ratio [95% CI] for poor CCC 3.18 [2.20–4.74], p<0.001) and women (odds ratio [95% CI] for poor CCC 3.10 [1.36–7.85], p=0.011) when the sex-specific analysis was performed. ConclusionsPlasma ET-1 level may be a useful, easily available marker for predicting the degree of CCC in patients with ≥95% coronary chronic occlusion.

Circulation : Clinical Summaries

<i>Circulation</i> : Clinical Summaries

Interrogating the Functional Correlates of Collateralization in Patients with Intracranial Stenosis Using Multimodal Hemodynamic Imaging.

The importance of collateralization for maintaining adequate cerebral perfusion is increasingly recognized. However, measuring collateral flow noninvasively has proved elusive. The aim of this study was to assess correlations among baseline perfusion and arterial transit time artifacts, cerebrovascular reactivity, and the presence of collateral vessels on digital subtraction angiography. The relationship between the presence of collateral vessels on arterial spin-labeling MR imaging and DSA was compared with blood oxygen level-dependent MR imaging measures of hypercapnic cerebrovascular reactivity in patients with symptomatic intracranial stenosis (n = 18). DSA maps were reviewed by a neuroradiologist and assigned the following scores: 1, collaterals to the periphery of the ischemic site; 2, complete irrigation of the ischemic bed via collateral flow; and 3, normal antegrade flow. Arterial spin-labeling maps were scored according to the following: 0, low signal; 1, moderate signal with arterial transit artifacts; 2, high signal with arterial transit artifacts; and 3, normal signal. In regions with normal-to-high signal on arterial spin-labeling, collateral vessel presence on DSA strongly correlated with declines in cerebrovascular reactivity (as measured on blood oxygen level-dependent MR imaging, P < .001), most notably in patients with nonatherosclerotic disease. There was a trend toward increasing cerebrovascular reactivity with increases in the degree of collateralization on DSA (P = .082). Collateral vessels may have fundamentally different vasoreactivity properties from healthy vessels, a finding that is observed most prominently in nonatherosclerotic disease and, to a lesser extent, in atherosclerotic disease.

A new risk scoring model for prediction of poor coronary collateral circulation in acute non-ST-elevation myocardial infarction.

We aimed to investigate the clinical features associated with development of coronary collateral circulation (CCC) in patients with acute non-ST-elevation myocardial infarction (NSTEMI) and to develop a scoring model for predicting poor collateralization at hospital admission. The study enrolled 224 consecutive patients with NSTEMI admitted to our coronary care unit. Patients were divided into poor (grade 0 and 1) and good (grade 2 and 3) CCC groups. In logistic regression analysis, presence of diabetes mellitus, total white blood cell (WBC) and neutrophil counts and neutrophil to lymphocyte ratio (NLR) were found as independent positive predictors of poor CCC, whereas older age (≥ 70 years) emerged as a negative indicator. The final scoring model was based on 5 variables which were significant at p < 0.05 level following multivariate analysis. Presence of diabetes mellitus, and elevated total WBC (≥ 7.85 × 103/μL) and neutrophil counts (≥ 6.25 × 103/μL) were assigned with 2 points; high NLR (≥ 4.5) with 1 point and older age (≥ 70 years old) with -1 point. Among 30 patients with risk score ≤ 1, 29 had good CCC (with a 97% negative predictive value). On the other hand, 139 patients had risk score ≥ 4; out of whom, 130 (with a 93.5% positive predictive value) had poor collateralization. Sensitivity and specificity of the model in predicting poor collateralization in patients with scores ≤ 1 and ≥ 4 were 99.2% (130/131) and +76.3 (29/38), respectively. This study represents the first prediction model for degree of coronary collateralization in patients with acute NSTEMI.

Abstract 61: MR Perfusion to Determine the Status of Collaterals in Patients With Acute Ischemic Stroke: Look Beyond Perfusion Time-maps

Purpose: Collateral flow is an independent predictor of reperfusion and infarct size in patients with acute ischemic stroke (AIS). MR perfusion time-maps show delayed perfusion but unable to differentiate antegrade from collateral flow if used alone. Using a multiparametric approach, we aimed to identify a perfusion biomarker that can represent the extent of collaterals in comparison to angiographic findings. Methods: AIS patients with MCA proximal occlusion who had baseline MRI and cerebral angiography included. MR perfusion data were processed by Bayesian method to generate arterial tissue delay (ATD) maps at thresholds of 2 &amp; 6 seconds. The volume of delayed perfusion (Vol-ATD 2sec ), critical hypoperfusion (Vol-ATD 6sec ), and hypoperfusion (Vol-ATD 2sec-6sec ) in addition to corresponding rCBV and rCBF were calculated. Baseline angiography collaterals were dichotomized to poor (TICI ≤2a) or good collaterals (TICI≥ 2b). The association of perfusion biomarkers and status of collaterals was assessed by repeated measure of analyses and receiver operating characteristic (ROC) to determine the optimal parameters for predicting the status of collaterals. Results: In 37 patients included, 20 had good collaterals on cerebral angiography. After controlling for age, baseline NIHSS and infarct volume, multivariate logistic regression analysis identified rCBV (p=0.001) and hypoperfused volume (Vol-ATD 2sec-6sec ), but not rCBF, Vol-ATD 2sec or Vol-ATD 6sec , as independent predictors of good collaterals. ROC analysis showed AUC of 0.89 (sensitivity/specificity: 85%90%) for rCBV and AUC of 0.78 (sensitivity/specificity: 70%82%) for Vol-ATD 2sec-6sec . Hypoperfused tissue volume (Vol-ATD 2sec-6sec ) x its rCBV, termed hypoperfused tissue collateral index , remained an independent predictor of good collaterals with improved diagnostic accuracy over each measure alone (AUC: 0.96, sensitivity/specificity: 91%100%). Conclusions: Multiparametric MR perfusion can be used to assess the status of collaterals in patients with AIS. Hypoperfused tissue collateral index defined as hypoperfused volume (Vol-ATD 2sec-6sec ) x rCBV is a new perfusion index with diagnostic accuracy of 96% compared to angiographic findings to predict status of collaterals.

Abstract 11416: The “Natural History” of Intra-operative Pulmonary Artery Stents: A 20-year Perspective

Background: Branch pulmonary artery (PA) stenoses are typically treated with catheter-based percutaneous therapies or surgical arterioplasty. Intra-operative (intra-op) PA stent placement is an alternative strategy. In this study, we sought to describe our 20-year experience with intra-op PA stent placement and to evaluate long-term patient outcomes, specifically the need and risk factors for re-intervention. Methods: We performed a retrospective review of all intra-op PA stents placed at our institution from 1994-2013. Patient and stent characteristics and outcome data were collected. Risk factors associated with re-intervention were identified using univariate cox regression analysis. Results: Eighty-one PA stents were placed in 68 patients, mostly to treat proximal PA stenoses (85%). Stent implantation was acutely successful in 67 patients (98.5%) with a procedural complication rate of 4.4%. Stents capable of being dilated to large diameters (“adult-size”) were used in 97% of patients. At hospital discharge, 93% of patients had no or mild residual PA stenosis by echocardiogram. During a median follow-up period of 6 years (interquartile range 0.9-12.7), 31 patients (46%) underwent PA re-intervention with a median time to first re-intervention of 2.5 years. Risk factors for re-intervention included age &lt; 18 months (Hazard ratio [HR] 3.26, p=0.002) and body surface area &lt; 0.47 m2 (HR 3.47, p=0.001) at the time of stent implantation, and the presence of multiple aorto-pulmonary collaterals in patients with tetralogy of Fallot (HR 3.19, p=0.02). Conclusions: Intra-op PA stent implantation is technically feasible with low procedural complications. It offers several advantages over transcatheter stenting, including the ability to implant adult-size stents in small patients while avoiding injury to percutaneous vessels, to position and flare stents to facilitate future percutaneous stent re-dilation, and to access the PAs directly, which shortens procedural time and eliminates radiation exposure. It also may prevent re-stenosis from scar tissue caused by patch arterioplasty. A future direct comparison of intra-op PA stenting to catheter-based stenting and surgical arterioplasty for PA stenosis is necessary.

GW26-e5439 Increased serum level of soluble VEGF receptor-1 is associated with low coronary collateralization in patients with stable coronary artery disease

The present study investigated whether serum levels of soluble vascular endothelial growth factor receptor (sVEGFR)-1, -2 and -3 are related to low coronary collateralization in patients with stable coronary artery disease. Serum levels of sVEGFR-1, -2, -3, VEGF and high-sensitivity C-reactive