Native Artery Research Articles

Different vasoreactivity of arterial bypass grafts versus native coronary arteries in response to acetylcholine.

Coronary angiography is often performed in patients with recurrent angina after successful coronary artery bypass grafting (CABG) in search of the progression of atherosclerosis. However, in many of these patients, no relevant stenosis can be detected. We speculate that coronary spasm may be associated with angina in these patients. From 2307 patients with unobstructed coronaries who underwent intracoronary acetylcholine spasm provocation testing (ACh-test) between 2012 and 2016, 54 consecutive patients who fulfilled the following inclusion criteria were included in this cohort study: previous left internal thoracic artery (LITA) bypass on the left anterior descending (LAD) coronary artery, ongoing/recurrent angina pectoris, no significant (< 50%) coronary artery or bypass stenosis. In all participants, the ACh-test was performed via the LITA bypass. In 14 patients (26%) the ACh-test elicited epicardial spasm of the LAD distal to the anastomosis (≥ 90% diameter reduction with reproduction of the patient's symptoms and ischemic ECG shifts). Microvascular spasm (reproduction of symptoms and ischemic ECG-changes but no epicardial spasm) was seen in 30 patients (55%). The ACh-test was normal in the remaining 10 patients (19%). ACh-testing did not elicit any relevant vasoconstriction in the LITA bypasses in contrast to the LAD on quantitative coronary analyses (4.89 ± 7.36% vs. 52.43 ± 36.07%, p < 0.01). Epicardial and microvascular coronary artery spasm are frequent findings in patients with ongoing or recurrent angina after CABG but no relevant stenosis. Vasoreactivity to acetylcholine is markedly different between LITA bypasses and native LAD arteries with vasoconstriction almost exclusively occurring in the LAD.

Long-term Results of Renal Artery Patency in Physician-modified Endografts for Juxtarenal Aneurysms

Renal artery stents are commonly placed in physician-modified fenestrated endografts for juxtarenal aortic aneurysms, but long-term outcomes of these stents is unknown. The purpose of this study was to identify the long-term outcome of stented renal arteries in patients who undergo a physician-modified endovascular graft (PMEG) for repair of juxtarenal aortic aneurysms. Data were prospectively collected on patients treated with PMEG from August 2011 to September 2019 in a prospective, consecutively enrolling investigational device exemption clinical trial (NCT #01538056). Anatomic criteria, including native renal artery stenosis and angulation, were systematically measured using preoperative computed tomography. The primary outcome of renal artery reintervention after PMEG was assessed with Kaplan-Meier survival estimation. Cox proportional hazard models were used to predict renal artery reintervention after PMEG, adjusting for preoperative demographic and patient risk factors, antiplatelet use prestent and poststent placement, and evidence of preoperative stenosis by duplex criteria. We studied 141 patients who underwent PMEG during the study period, representing 282 renal arteries. During the study period, 246 out of 282 (87%) renal arteries were stented. Inability to cannulate the renal artery as the most common cause (n = 9) of inability to stent the artery. However in 25% (n = 9) of these situations, the renal artery was preserved and in 25% (n = 9) an effective proximal seal zone was obtained without renal stenting. Preoperative ostial stenosis was present in 23% (n = 62) of renal arteries by diameter reduction and 22% (n = 58) by duplex criteria. Over a follow-up period of 5 years, 15 renal arteries in 13 patients required reintervention, for an overall reintervention rate of 6.1%. All stented renal arteries remained patent. Median follow-up was 2 years (interquartile range, 0.5-4 years). The most common cause for reintervention during the first 6 months was failure to cannulate during the initial PMEG (15%, n = 2). In-stent restenosis was the reason for reinterventions for 30% (n = 4). Long-term follow-up revealed stent separation (15%, n = 2) and type IIIc endoleak (15%, n = 2) as the most common cause for reintervention. The predicted reintervention free survival of the renal artery at 5 years is 90% (95% confidence interval, 82%-95%) (Figure). Using a Cox proportional hazard model, no significant anatomic or patient-based predictors of reintervention were identified. Renal artery stents placed during physician-modified endografts show excellent long-term durability with a low rate of reintervention. No preoperative renal artery measurements are predictive of either renal stent patency or reintervention.

Mid-Term Outcomes of Thrombolysis for Acute Lower Extremity Ischemia at a Tertiary Care Center

Acute limb ischemia (ALI) is challenging to treat because of high morbidity and mortality. Endovascular-first options beginning with thrombolysis are technically feasible with similar results to open surgery. We examined our experience with thrombolysis to identify patients and target conduits that are predictive of improved outcomes. We performed a retrospective review of our institutional database of thrombolysis cases for arterial lower extremity disease. Thrombolysis was the index procedure, and any subsequent treatment was a reintervention. Conversion to open surgery perioperatively such as thromboembolectomy or bypass was considered a technical failure. Primary outcomes included primary patency, secondary patency, amputation-free survival (AFS), and survival. Secondary outcomes included conversion to open, reintervention <30 days, and amputation <30 days. Descriptive statistics and analysis of variance were performed for preoperative and intraoperative risk factors. Kaplan-Meier estimation and Cox proportional hazard models were used for primary and secondary outcomes. Ninety-nine patients with ALI were treated with thrombolysis from 2007 to 2017. Thrombolysis was attempted on native artery (40%), vein bypass (7%), prosthetic bypass (33%), and stent (19%). Rutherford class distribution was 50% class 1, 41% class 2a, 5% class 2b, and 3% class 3. Technical success was 70%, characterized by an all-endovascular approach, patency at 30 days, and AFS for 30 days. Primary patency at 1- and 2-years was 31% and 22%, respectively. Secondary patency at 1- and 2-years was 39% and 27%, respectively. Overall, 30% required conversion to open surgery at the time of the index procedure, 7% reintervention <30 days, 5% mortality <30 days, and 5% major amputation <30 days. Prosthetic grafts and vein bypasses had the worst primary and secondary patency (P<0.05). Five out of 7 vein bypasses required open conversion. Thrombolysis of native arteries was most successful maintaining primary patency (P<0.05), secondary patency (P<0.05), and AFS (P<0.05). Patients who had adjunctive procedures at the time of thrombolysis had a significantly greater primary patency (P<0.05) and secondary patency (P<0.05) but not greater AFS. Outcomes in thrombolysis for ALI have not significantly improved 20years after the STILE trial. Technical success and mid-term patency rates are modest at best. Thrombolysis of vein bypasses and prosthetic grafts have poor technical success and primary patency compared with native arteries. However, aggressive adjunctive interventions during thrombolysis appear to improve primary and secondary patency.

Duplex ultrasound follow-up after fenestrated and branched endovascular aneurysm repair (FEVAR and BEVAR)

Endovascular aneurysm repair (EVAR) is now the predominant method for treatment of infrarenal abdominal aortic aneurysms. Although EVAR has numerous advantages over standard open surgical repair, it also exposes patients to risks such as aneurysm sac enlargement, endoleaks, and graft migration, which make surveillance or follow-up mandatory. Fenestrated (FEVAR) and branched (BEVAR) endografts have extended the application of EVAR to juxtarenal, pararenal/paravisceral, and thoracoabdominal aneurysms, with some complex aneurysms requiring combined approaches (F-BEVAR). Duplex ultrasound has been recommended as an alternative to frequent computed tomography imaging for EVAR follow-up when it can provide the clinically necessary information. The major components of a post-EVAR duplex examination include measurement of aortic aneurysm sac size, assessment for endoleak, and evaluation of the endograft for patency and integrity. The duplex protocol for EVAR follow-up can be extended for follow-up after FEVAR, BEVAR, and F-BEVAR, with additional attention to the device components associated with fenestrations and branches. At the University of Washington, the physician-modified endovascular graft approach has been used for FEVAR. During these procedures, covered stents are placed in the renal arteries through fenestrations and the superior mesenteric artery is perfused through a fenestration, but typically remains unstented. Duplex scanning of the renal and mesenteric arteries has been performed preoperatively and at 30 days, 6 months, 1 year, and annually. In a review of patients having covered stents placed in non-stenotic renal arteries during FEVAR, both peak systolic velocity and the renal to aortic velocity ratio remained below the standard significant stenosis threshold in most patients. The duplex velocity criteria for stenosis in native renal arteries appeared to overestimate the severity of stenosis in renal artery covered stents. The unstented superior mesenteric artery remained widely patent in the presence of fenestrations or crossing struts and was not associated with endoleaks. Duplex ultrasound protocols for follow-up after FEVAR, BEVAR, and F-BEVAR can be based on those that have been established for standard EVAR, along with assessment of fenestrations and branches, as well as patency of the renal and mesenteric arteries.

Polylysine Enriched Matrices: A Promising Approach for Vascular Grafts

Cardiovascular diseases represent the leading cause of death in developed countries. Modern surgical methods show poor efficiency in the substitution of small-diameter arteries (<6 mm). Due to the difference in mechanical properties between the native artery and the substitute, the behavior of the vessel wall is a major cause of inefficient substitutions. The use of decellularized scaffolds has shown optimal prospects in different applications for regenerative medicine. The purpose of this work was to obtain polylysine-enriched vascular substitutes, derived from decellularized porcine femoral and carotid arteries. Polylysine acts as a matrix cross-linker, increasing the mechanical resistance of the scaffold with respect to decellularized vessels, without altering the native biocompatibility and hemocompatibility properties. The biological characterization showed an excellent biocompatibility, while mechanical tests displayed that the Young’s modulus of the polylysine-enriched matrix was comparable to native vessel. Burst pressure test demonstrated strengthening of the polylysine-enriched matrix, which can resist to higher pressures with respect to native vessel. Mechanical analyses also show that polylysine-enriched vessels presented minimal degradation compared to native. Concerning hemocompatibility, the performed analyses show that polylysine-enriched matrices increase coagulation time, with respect to commercial Dacron vascular substitutes. Based on these findings, polylysine-enriched decellularized vessels resulted in a promising approach for vascular substitution.

Loss‐ And Gain of Function Mutations in the Type 1 IP3 Receptor (IP3R1) Modify Agonist‐Evoked Vasoactive Responses in Cerebral and Skeletal Muscle Resistance Arteries From Adult Mice

Calcium mobilization within vascular smooth muscle and endothelial cells of small resistance arteries plays a critical role in agonist‐evoked vasoconstriction and dilation, respectively. Despite the recognized contribution of IP3‐mediated intracellular Ca2+ release for agonist‐evoked vasoactive responses, it has been difficult to study this process acutely in native arteries, due to the lack of selective pharmacological agents or experimental strategies to target the predominant IP3R1. In humans, heterozygous mutations in the IP3R1 are known to produce either loss‐of‐function (LOF) or gain‐of‐function phenotypes for Ca2+ release that impact cerebellar activity (e.g. ataxia), yet it remains unclear how these global mutations affect the cardiovascular system. To facilitate such investigation, we have engineered novel genetic knock‐in mice harbouring a single amino acid mutation at position Asp2594 in the transmembrane S6 helix of the endogenous IP3R1 Ca2+ release channel that confers either a LOF (Asp2594Ala) or GOF (Asp2594Lys) phenotype, respectively. In permeabilized HEK293 cells expressing these mutant receptors, the LOF mutation shifted IP3‐mediated ER Ca2+ release ~2‐fold to the right, whereas the GOF mutation produced a 2.3‐fold leftward shift compared with wild‐type (WT) IP3R1. In endothelium‐denuded cerebral arteries pressurized to 10 mmHg, the sensitivity of serotonin‐evoked vasoconstriction was reduced in vessels from heterozygous LOF mice compared with WT, whereas agonist responsiveness was enhanced in arteries from heterozygous GOF mice. Vasoconstriction in response to the thromboxane receptor agonist U46619 was modestly enhanced by the GOF mutation, but largely unaffected in arteries from LOF mice. In cannulated cremaster skeletal muscle arteries from LOF and GOF mice pressurized to 70 mmHg, the sensitivity of endothelium‐dependent, acetylcholine‐mediated inhibition of myogenic tone was right shifted (3.7‐fold) and left shifted (2‐fold), respectively, compared with vessels from WT. Comparable changes in functional sensitivity were observed in response to the endothelium‐dependent vasodilator bradykinin. In contrast, dilation evoked by the NO donor sodium nitroprusside was not different among the three genotypes. Collectively, these data demonstrate that genetic modification of IP3R1‐mediated Ca2+ mobilization in small resistance arteries functionally impacts agonist‐evoked vasoactive responses. These observations highlight the importance of IP3R1 activity in the vascular wall, and further implicate vascular impairment as a contributing factor to the neurological dysfunction observed in patients with LOF and GOF IP3R1 mutations.Support or Funding InformationThis work was funded by the following research grants from the Canadian Institutes of Health Research: MOP‐97988 (WCC), MOP‐142467 (APB) and PJT‐155963 (WC, WCC and APB).

AIUM Practice Parameter for the Performance of an Ultrasound Examination of Solid-Organ Transplants.

AIUM Practice Parameter for the Performance of an Ultrasound Examination of Solid-Organ Transplants.

Comparison of Ultrasound-Accelerated Versus Multi-hole Infusion Catheter-Directed Thrombolysis for the Treatment of Acute Limb Ischemia

Retrospective single-center review between 2006 and 2008 Thrombolysis of thrombosed native arteries and arterial bypasses was performed with Uni-Fuse multihole catheters (AngioDynamics, Latham, NY) in 69 cases and EKOS ultrasound-accelerated catheters (EKOS Corporation, Bothell, Wash) in 22 cases. All patients were initially treated with the power-pulse feature of an AngioJet catheter (Boston Scientific, Marlborough, Mass) administering 10 mg of alteplase (tissue plasminogen activator [tPA]) followed 20 minutes later by rheolytic catheter-directed thrombectomy. Residual thrombus was treated with either Uni-Fuse or EKOS catheters with tPA infused at 0.5 to 2.0 mg/h overnight. The mean duration of thrombolysis, mean volume of tPA, technical success, and complications were similar in both groups. The standard multihole infusion catheter demonstrates similar clinical safety and efficacy as the ultrasound-accelerated EKOS system to treat acute arterial limb ischemia.

Design and comprehensive assessment of a biomimetic tri-layer tubular scaffold via biodegradable polymers for vascular tissue engineering applications.

Considering the structural complexity of the native artery wall and the limitations of current treatment strategies, developing a biomimetic tri-layer tissue-engineered vascular graft is a major developmental direction of vascular tissue regeneration. Biodegradable polymers exhibit adequate mechanical characteristics and feasible operability, showing potential prospects in the construction of tissue engineering scaffold. Herein, we present a bio-inspired tri-layer tubular graft using biodegradable polymers to simulate natural vascular architecture. The inner layer made of polycaprolactone (PCL) nanofiber possesses high tensile strength and contributed to endothelial cell adhesion and proliferation. The middle layer consisted of poly(lactic-co-glycolide) (PLGA) with a three-dimensional porous structure is appropriate for vascular smooth muscle cells (SMCs) penetration. The polyurethane (PU) was selected to be the outer layer, aiming to hold the entire tubular structure, suggesting superior mechanical properties and ideal biocompatibility. Adhesion between independent layers is achieved by thermal crosslinking. The compliance, burst pressure and suture retention force of the tubular scaffold were 2.50±1.60%, 2737.73±583.41mmHg and 13.06±1.89N, respectively. The in vivo study of subcutaneous implantation for 8weeks demonstrated the biomimetic tri-layer vascular graft could maintain intimal integrity, cell infiltration, collagen deposition and scaffold biodegradation. Overall, the biomimetic tri-layer vascular graft promises to be a potential candidate for vascular replacement and regeneration.

Role of Multi-Detector CT Angiography in Assesmente of Athrosclerotic Coronary Artery Disease

Background: Imaging has a critical role in the diagnosis and evaluation of cardiac diseases, beginning with chest radiography and fluoro-scopy and progressing to coronary angio-graphy, echocardiography, nuclear medicine and recently multidetector computed tomo-graphy (MDCT) as well as magnetic resonance (MR) imaging&#x0D; Objective: To highlight the role of Multi-detector CT in the evaluation of coronary artery disease and its importance of being noninvasive diagnostic technique.&#x0D; Methods: A cross sectional study for 20 patients. Patients were asked to fast 6 hours prior to the examination and the patients with heart rates above 65 beats per minute were given cardio-selective beta-blocker and for heart rate above 75 (up to 85) beat/min, the best systole phase was used for reconstructing our images&#x0D; Results: for Evaluation of native coronary arteries, the CTCA showed significant lesions (occlusion or &gt;60 % stenosis) in the native arteries of 13 patients and insignificant lesions in 7 patients. &#x0D; Evaluation of CABG (8 arterial grafts); for (LIMA) graft, 83% were patented, and 17% were narrowed and 100 % of (radial graft) were patent. For Venous Grafts the study included 10 venous grafts; 70 % were patent, 20% were narrowed and 10 % were totally occluded.&#x0D; Conclusion: The multi-slice CTCA is now a clinically reliable noninvasive tool that allows the evaluation of the native coronary arteries, the bypass grafts, coronary stents.

P.108 Cannabinoid receptor 1 epigenetic regulation and effect of probiotic treatment in anorexia nervosa

Acute lower extremity ischemia (ALI) is a serious condition with substantial morbidity and mortality. ALI refers to recent onset of lower extremity pain; long-standing lower extremity ischemia is dealt with elsewhere in this book. If ALI is severe and prolonged, the patient may develop progressive paresthesia, motor dysfunction, and eventually tissue infarction in the lower extremity. The rapidity plus severity of the onset of symptoms depend on the location, extent, and degree of collateral pathways around the obstruction. The estimated incidence of ALI is approximately 1.4–2.6 cases per 10,000 patients per year. ALI accounts for approximately 20% of inpatient peripheral vascular cases and amputation rates of 10%–30%. After the presenting event, the 1-year mortality rates of ALI are approximately 15%–20% along with low amputation-free survival rates of approximately 50%–65%. The two principal causes of ALI are (1) embolic, in which an artery may become occluded when an embolus becomes dislodged from a proximal source, and (2) thrombotic, in which occlusion of a native artery occurs in the setting of severe atherosclerotic disease.

Real-World Outcomes of EKOS Ultrasound-Enhanced Catheter-Directed Thrombolysis for Acute Limb Ischemia

Ultrasound-enhanced catheter-directed thrombolysis (UET) using the Ekosonic® Endovascular System device for acute, peripheral arterial ischemia has been purported in clinical trials to accelerate the fibrinolytic process to reduce treatment time and lytic dosage. We aim to describe outcomes of UET in a real-world clinical setting. We performed a retrospective review of all patients undergoing UET for acute limb ischemia at a single institution. Data collected included patient demographics, procedural details, and 30-day and 1-year outcomes. The primary endpoints for analysis were major adverse limb events (MALEs; reintervention and/or amputation) and mortality within 30-days and 1-year. Secondary endpoints included technical success, use of adjunctive therapies, and postoperative complications. A total of 32 patients (mean age 67.4±14.9years; 25% women) underwent UET for acute limb ischemia between 2014 and 2018. The Rutherford Acute Limb Ischemia Classification was Rutherford (R) 1 in 56.3%, R2a in 31.3%, and R2b in 12.5%. Etiology was thrombosis of native artery in 12.5% of patients, prosthetic bypass in 31.3%, autogenous bypass in 6.3%, and stented native vessel in 50.0%. Mean duration of thrombolytic therapy was 22.2±11.3hr, and mean tissue plasminogen activator dose was 24.5±15.3mg. MALEs occurred in 16.7% of patients within the first 30 days and 38.9% experienced a MALE by 1 year. Limb salvage at 30 days and 1 year was 93.8% and 87.5%, respectively. Ipsilateral reintervention was required in 12.5% of patients within 30days and 37.5% of patients within 1year. Overall mortality was 6.2% at 30 days and 13.5% at 1 year. In-line flow to the foot was re-established in 90.6% of patients, with a significant improvement in preoperative to postoperative ankle-brachial index (0.31±0.29 vs. 0.78±0.34, P<0.001) and number of patent tibial runoff vessels (1.31±1.20 vs. 1.96±0.86, P<0.001). There was no significant difference in revascularization success between occluded vessel types. All but one patient required adjunctive therapy such as further thromboaspiration, stenting, or balloon angioplasty. Major bleeding complications occurred in 3 patients (9.4%), including 1 intracranial hemorrhage (3.1%). UET with the EKOS device demonstrates acceptable real-world outcomes in the treatment of acute limb ischemia. UET is generally safe and effective at re-establishing in-line flow to yield high limb salvage rates. However, UET is associated with a high rate of reintervention. Further investigation is needed into specific predictors of limb salvage and need for reintervention, as well as cost-efficacy of this technology compared with that of traditional methods.

1165 Anomalous origin of the coronary artery arising from the opposite sinus: clinical impact and prognosis

Abstract Anomalous origin of the coronary artery arising from the opposite sinus (ACAOS) is an infrequent congenital heart disease (CHD). Clinical presentation is variable and there is controversy over its treatment in relation to the affected coronary artery and the type of path. Our objective was to analyze the anatomical characteristics of ACAOS, their clinical impact and prognosis. We selected all patients with diagnosis or confirmation of diagnosis of ACAOS by computerized tomography (CT) in our center between 2014-2019, excluding complex CHD. Their baseline characteristics, tests for ischemia and follow-up were analyzed. 40 patients were diagnosed of ACAOS, and 26 had a simple coronary anomaly (mean age 54 years, 65% male). The most prevalent ACAOS was the right coronary artery (47%) followed by left main (27%). 42% had an inter-arterial path. Figure. Atherosclerosis on the ACAOS was similar to native arteries (p= &amp;gt;0,05). 11 of 18 (61%) patients with follow-up in our center had ischemia testing (23 tests). Only 22% were positive. 6 patients had a revascularization procedure (3 surgical, 3 percutaneous) and 83% included an intervention on the ACAOS. During follow up there were 13 major cardiovascular events (MACE). We observed a tendency to a higher number of MACE in patients with an interarterial path, although it was not statistically significant (p = 0,06). One patient died of a non-cardiac cause during follow-up. Only 4/18 patients (22%) had follow-up in the Adult CHD clinic. In our population ACAOS did not have statistically significant differences in the development of atherosclerosis compared to native arteries, tests for ischemia were mostly negative but there was a significant number of MACE so it is necessary to implement patient follow up in the specialized Adult CHD clinic. Baseline characteristics Hypertension 8 (35%) Type II diabetes mellitus 5 (22%) Dyslipidemia 9 (31%) Smoking history 10 (46%) Alcohol abuse 5 (22%) Previous symptoms 20 (80%) Ischemia on complementary tests 1 (8%) Diagnosis by coronariography 5/26 (19%) Diagnosis by computerised tomography 21/26 (81%) Anomalous artery atherosclerosis Moderate to severe atherosclerosis 10/26 (38,5%) 5/10 (50%) Native artery atherosclerosis Moderate to severe atherosclerosis 11/26 (42,3%) 6/11 (54,6%) Abstract 1165 Figure.

Staged Treatment Using Right Ventricular Outflow Tract Stenting for Effective Augmentation of Native Pulmonary Arteries in a Case of Tetralogy of Fallot with Major Aortopulmonary Collateral Arteries

Staged Treatment Using Right Ventricular Outflow Tract Stenting for Effective Augmentation of Native Pulmonary Arteries in a Case of Tetralogy of Fallot with Major Aortopulmonary Collateral Arteries

Standardized approach to result analysis and interpretation of initial experience of coronary computed tomography angiography in a tertiary care hospital.

Objective:To have a systematic standardized approach to performing and interpretation of coronary CT Angiography (CTA) in order to maintain and enhance the diagnostic accuracy of the imaging modality.Methods:This retrospective observational study was performed in Radiology Department, Lady Reading Hospital, Medical Teaching Institute, Peshawar, Pakistan from August 2018 to September 2019. Patients referred for coronary CT angiography were screened and prepared in radiology department. The examination was performed on Toshiba-160 slice CT Scanner (Prime Aquilion) utilizing standardized protocols tailored towards optimum image acquisition. Interpretation of the images were based on the guidelines provided by the Society of Cardiovascular Computed Tomography (SCCT).Results:Total 95 CTCA procedures were performed in the department, out of which 85 were included in study showing 49(57%) as normal and 36(42%) were positive for coronary disease. Of the abnormal cases 16(18.8%) had mild disease, nine (10.6%) patients had moderate disease, while severe disease was noted in 11 (12.9%) cases. Coronary quantitative stenosis revealed five cases (5.9%) with LAD involvement only and five (5.9%) with severe triple vessel disease. The remaining varied in degree of stenosis and number of segments involved. Post CABG were 14 cases (16%) and native arteries showed triple vessel disease. CTA for percutaneous stent patency were three (3.5%) cases with 100% stent patency.Conclusion:Patient selection with tailored protocols are the mainstay for achieving optimal images. This form the basis for accurate interpretation, based on a standardized and systematic approach, utilizing various post processing tools, in order to maintain the high diagnostic accuracy of this semi-invasive, safe imaging modality in a variety of patients suspected of coronary artery disease, coronary artery bypass grafts and stent patency.

P1564 Changes in coronary flow velocity measuring during coronary bypass grafting can predict elevation of cardiac troponin

Abstract Background Stenosis of a coronary artery results in an increase in flow velocity in the pathologic segment. Effective grafting should decrease the stenotic native coronary velocity according to a hemodynamic law. The range of decreased velocity can hypothetically reflect the effectiveness of a graft. Grafting effect insufficiencies often cause elevations in periprocedural cardiac troponin (cTn) elevation. The aim of the study is to determine, if measuring coronary flow velocity changes during coronary artery bypass grafting (CABG) can predict further cTn elevation. Methods and results Consecutive 68 patients (48 men, 64 ± 9 years old), who were referred for CABG, were included into the study. A standard basic perioperative transesophageal echocardiography (TEE) examination was performed with additional scans of the left main, left anterior descending (LAD), and circumflex (LCx) arteries’ proximal segments. Measurements of coronary flow velocities was performed before and after grafting in the same sites of the arteries. The maximal value of cTnI within 48 hours after CABG was accounted for in the analysis. All patients had arterial hypertension, 15 patients (22%) had diabetes mellitus, 12 patients (18%) was current smokers. Forty-one patients (60%) had prior myocardial infarctions, 18 persons (26%) had previous coronary stenting. The ejection fraction before the operation was 56 ± 13%. Before grafting the mean velocity in the left main artery was 79 cm/s (25th-75th quartile, 42-111), in LAD 98 cm/s (25th-75th quartile, 71-125), and in LCx 116 cm/s (25th-75th quartile, 68-156). There was a strong significant correlation between changes in coronary flow velocities and the value of cTnI (R = 0.56, p &amp;lt; 0.0004). The patients with and without significant elevations in cTnI had differences in coronary velocity changes before and after grafting (p &amp;lt; 0.009). Patients with elevated cTnI in more than 5 times, had, on average, an increase in the velocities for native arteries of 21 ± 19 cm/s. Conclusion Coronary flow velocity assessment during CABG could predict an elevation of cardiac troponins after cardiac surgery. Abstract P1564 Figure.

Drug Coated Balloons vs. Conventional Balloon Angioplasty for Bypass Vein Graft stenosis – A Randomized Controlled Trial

Introduction - Stenosis and restenosis are known complications of endovascular treatment of native arteries and bypass vein grafts in peripheral arterial disease (PAD). (1,2) This may lead to loss of the bypass graft, which can be a problem due to the limited availability of autologous vein material. Drug-coated balloons seem to be effective in the treatment of native artery stenosis (3). The biomechanical and anatomical properties of vein grafts differ greatly from native arteries, and less is known about the potential of drug-coated devices in this field. One randomized trial did not demonstrate benefit from use of DCBs over BA in bypass vein grafts. (4) Similar results were observed in a retrospective study comparing BA to DCB in peripheral grafts (5). The aim of this study was to evaluate the effect of drug-coated balloons in the treatment of vein graft stenoses. Design: Single-center, parallel, randomized controlled trial. Block randomized by sealed envelope 1:1. Methods - 60 patients treated for primary or recurrent stenosis in venous bypass grafts were randomized to drug-coated balloon (DCB) (n=30) or standard balloon angioplasty (BA) (n=30). Follow-up was 1 year. Primary outcome measures were target lesion revascularization (TLR) and graft occlusion. Primary assisted patency and secondary patency were also assessed. Results - 57 cases were ultimately included in the study. 3 randomized cases were excluded due to primary technical failure (graft rupture during predilatation and bail-out stenting (N=2), aborted procedure (N=1)). Six patients died during follow-up (DCB 4, BA 2) and one patient underwent major amputation (BA group). 23 patients underwent re-revascularization of the same segment (DCB 10/29, 34.5 % vs. BA 13/28, 46.4 %, p=0.333). The overall TLR-rate at one year was 34.5 % and 46.4 % in the DCB and BA groups respectively (p=0.33). 5/57 (8.8 %) grafts occluded during the follow-up, 1/29 (3.4 %) and 4/28 (14.3 %) in the DCB and BA groups respectively (p=0.36). Secondary patency was 100 % in the DCB group compared to 89.3% in the BA group (p=0.076). In subanalysis including only de novo lesions TLR was significantly lower in grafts that were treated with DCB compared to BA (15 % vs. 18.9 %, P=0.03). Conclusion - There is a trend toward benefit from DCBs in the treatment of graft stenosis; this difference is significant in previously untreated lesions. There has been hesitation towards using drug-coated balloons as a first choice in the treatment of graft stenosis. Our results suggest that this hesitation might be unfounded, especially in de novo lesions. More data is needed to accurately select which lesions will benefit from DCBs. Furthermore; histological studies on paclitaxel uptake and response in the arterialized venous wall are warranted.

Retrograde insertion of the outback reentry device from a tibial artery for complex infrainguinal recanalization

IntroductionRecanalization in an antegrade fashion in complex infrainguinal arterial disease can prove challenging and use of the Outback re-entry device via a retrograde approach may be an option.Case presentationUsing an antegrade approach we were unable to cross the native occluded superficial femoral artery in a patient after two occluded bypasses, with ulcers and was unfit for general anaesthesia.We successfully attempted retrograde re-entry using an Outback device via a phantom segment of the anterior tibial artery. After angioplasty and stenting a satisfactory result was achieved with one artery runoff.ConclusionsAt the 24 months follow up reconstruction was patent and ulcers were healed after 4 months.The outcome of more cases will be decisive for the broader applicability of this technique.

Covered Stent Graft for Relining of Occluded Femoro-popliteal Bypass

Introduction: Chronic long femoro-popliteal occlusions remain a significant challenge. In case of failure of endovascular procedures bypass surgery remains an important tool for revascularization in these patients. If both endovascular and open revascularization have failed the risk of major amputation is high. Methods: A 69-year old man with an extensive medical history including cardiac arrest, myocardial infarction, CABG and stroke presented with gangrene of his left forefoot. His vascular history included an occluded left sided above-the-knee prosthetic bypass with stents across the distal anastomosis and popliteal artery, an occluded left sided below-the-knee venous bypass and multiple left groin procedures for thrombectomies and correction of a false aneurysm of the proximal anastomosis of the above-the-knee bypass. Ultrasound guided retrograde puncture of the right common femoral artery was performed. A crossover sheath was placed and the occluded bypass was engaged. Unfortunately it proved impossible to cannulate either the occluded above- or below-the-knee bypasses. An attempt to recanalize the native femoral artery also failed due to the impossibility for reentry into the true lumen. Then a retrograde puncture of the popliteal stent was performed, a guidewire was advanced and the occluded above-the-knee bypass was cannulated in a retrograde way. After picking up the wire in the common femoral artery we then proceeded in an antegrade way and predilated the occluded bypass and occluded part of the popliteal artery. The occluded bypass was then relined with two 25 cm length covered stent grafts. At the end of the procedure the second and third toe of the left foot were amputated. He was discharged 2 days later. Results: During follow-up the wound of the amputation healed and he required no additional amputations. At 6 month follow-up the surveillance duplex ultrasound revealed a 80% distal edge stenosis which was treated succesfully with angioplasty. Conclusion: This is a case report of succesfull percutaneous relining of an occluded femoropopliteal bypass using covered stent grafts in a very high-risk patient with a history of multiple vascular procedures and an inaccessible ipsilateral groin. Disclosure: Nothing to disclose

Acute Aortic Occlusion: A Nationwide Cohort Study

Introduction: Acute aortic occlusion (AAO) is a rare and potentially catastrophic event. The aim was to extend the understanding of this condition, and to study time-trends and long-term survival. Methods: A well validated nationwide vascular database, where patients had been entered prospectively, was used to identify the cases, and a cross-link to the Population Registry to study long-term survival. Results: During the 21-year study-period (1994-2014), 715 patients had been treated for AAO with a yearly incidence of 3.7 per million inhabitants. Mean age was 69.7 years, 50.5% were women and mean follow-up was 5.2 years. The aetiology for AAO was in-situ thrombosis in 458 patients (64.1%), saddle embolus in 152 (21.3%), and occluded grafts/stents/stentgrafts in 105 (14.7%). The proportion of occluded grafts/stents/stentgrafts increased during the study period with a simultaneous reduction in the proportion of in-situ thrombosis, the proportion of saddle embolus was relatively unaltered over time. Grafts/stents/stentgrafts were occluded after a mean of 39.2 months from initial surgery. Most patients (81.2%) presented with bilateral acute limb ischaemia. The most commonly used methods for revascularization were thrombo-embolectomy (32.0%), thrombolysis (22.4%), axillary-bifemoral bypass (18.9%) and aorto-biilical/bifemoral bypass (18.2%). The choice of revascularization technique depended on the aetiology of the occlusion. Amputation was required in 8.6% of the cases and 19.9% of the patients died within the first month after surgery. The 30-days mortality rate was lower after occluded grafts/stents/stentgrafts (9.5%) and higher in the saddle embolus group (30.9%, p<0.001). There was a reduction in overall 30-days mortality over time (25.0% 1994-2000 versus 15.3% 2008-2014, p=0.008). There were significant differences in survival between the subgroups, depending on aetiology, throughout the follow-up, although the difference occurred early after the event (log-rank, p<0.001, see the attached Figure). Conclusion: Mortality after AAO is high, but improving over time. The proportion of AAO secondary to occluded grafts/stents/stentgrafts increases, and the proportion secondary to native artery thrombosis decreases, over time.