Polytetrafluoroethylene-covered stent and coronary artery aneurysms

Coronary Artery Aneurysms, Arteriovenous Malformations, and Spontaneous Dissections-A Review of the Evidence

BACKGROUND

Coronary artery aneurysms (CAAs), coronary arteriovenous malformations (CAVMs), and spontaneous coronary artery dissections (SCADs) are rare clinical entities, and much is unknown about their natural history, prognosis, and management.

METHODS

A systematic search of MEDLINE, Embase, and Cochrane Library databases was performed in March 2023 to identify published papers related to CAAs, CAVMs, and SCADs.

RESULTS

CAAs are found in 0.3% to 12% of patients undergoing angiography and are often associated with coronary atherosclerosis. They are usually asymptomatic but can be complicated by thrombosis in up to 4.8% of patients and rarely by rupture (0.2%). CAAs can be managed medically, percutaneously with stents or coil embolization, and surgically. The most common surgical procedure is ligation of the aneurysm, followed by coronary artery bypass grafting. The incidence of CAVMs is 0.1% to 0.2% in patients undergoing angiography, and they are most likely associated with congenital abnormal development of the coronary vessels. The diagnosis of CAVMs is usually incidental. Surgical or percutaneous intervention is indicated for patients with large CAVMs, which carry a potential risk of myocardial infarction. SCADs represent 1% to 4% of all acute coronary syndromes and typically affect young women. SCADs are strongly correlated with pregnancy, suggesting the role of sex hormones in their pathogenesis. Conservative management of SCAD is preferred for stable patients without signs of ischemia as spontaneous resolution is frequently reported. Unstable patients should undergo revascularization either percutaneously or with coronary artery bypass grafting.

CONCLUSIONS

Further evidence regarding the management of these rare diseases is needed and can ideally be derived from multicenter collaborations.

Polymeric Semiconductor in Field-Effect Transistors Utilizing Flexible and High-Surface Area Expanded Poly(tetrafluoroethylene) Membrane Gate Dielectrics

Organic field-effect transistors (OFETs) were fabricated using three high-surface area and flexible expanded-poly(tetrafluoroethylene) (ePTFE) membranes in gate dielectrics, along with the semiconducting polymer poly[2,5-bis(2-octyldodecyl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione-3,6-diyl)-alt-(2,2':5',2″:5″,2‴-quaterthiophen-5,5‴-diyl)] (PDPP4T). The transistor behavior of these devices was investigated following annealing at 50, 100, 150, and 200 °C, all sustained for 1 h. For annealing temperatures above 50 °C, the OFETs displayed improved transistor behavior and a significant increase in output current while maintaining similar magnitudes of Vth shifts when subjected to static voltage compared to those kept at ambient temperature. We also tested the response to NO2 gas for further characterization and for possible applications. The ePTFE-PDPP4T interface of each membrane was characterized via scanning electron microscopy for all four annealing temperatures to derive a model for the hole mobility of the ePTFE-PDPP4T OFETs that accounts for the microporous structure of the ePTFE and consequently adjusts the channel width of the OFET. Using this model, a maximum hole mobility of 1.8 ± 1.0 cm2/V s was calculated for the polymer in an ePTFE-PDPP4T OFET annealed at 200 °C, whereas a PDPP4T OFET using only the native silicon wafer oxide as a gate dielectric exhibited a hole mobility of just 0.09 ± 0.03 cm2/V s at the same annealing condition. This work demonstrates that responsive semiconducting polymer films can be deposited on nominally nonwetting and extremely bendable membranes, and the charge carrier mobility can be significantly increased compared to their as-prepared state by using thermally durable polymer membranes with unique microstructures as gate dielectrics.

Coronary Involvement of Behçet's Disease: Saccular Coronary Artery Aneurysm

Coronary artery aneurysms (CAAs) are rarely reported in large angiographic series. The majority are atherosclerotic in origin. Other causes are connective tissue disorders, trauma, vasculitis, congenital, mycotic, and idiopathic. We herein present the case of an symptomatic patient with a giant left anterior descending artery aneurysm. The CAA was successfully treated by surgical resection and a mammary artery bypass graft.

Progression and interventional therapy of a coronary pseudoaneurysm: a case report

Background

Coronary pseudoaneurysms (PSAs) occur as a rare complication following drug-eluting stent implantation and have been reported to occur between 1 week and 4 years after implantation. Most of them remain in a stable state, but progression of PSAs increases the risk of rupture and haemorrhagic cardiac tamponade.

Case summary

Here, we present a case of a 55-year-old patient, who developed a PSA of the proximal left circumflex artery after stent implantation of the left main artery, left anterior descending artery, and left circumflex artery. Within <1 year, the patient was readmitted to different hospitals due to cardiac decompensation and myocardial infarction. Thereafter, coronary angiography and computed tomography scans were performed, and progression of the PSA could be documented. Interventional therapy was chosen due to the high surgical risk of the patient. Implantation of a covered stent from the left main artery into the left anterior descending artery was chosen to treat the PSA, thereby silencing the chronically occluded left circumflex artery, followed by dilatation with a non-compliant balloon. The patient has remained asymptomatic in a 6-month follow-up.

Discussion

Coronary PSA should be controlled with respect to progression, and appropriate therapy can be chosen for treatment.

Giant coronary artery aneurysm of the left main treated with a covered stent: a case report

Background

Coronary artery aneurysms (CAAs) of the left main represent a small subset of coronary artery disease and are associated with cardiovascular death. Because of its rare entity, large data are lacking and therefore treatment guidelines are missing.

Case summary

We describe a case of a 56-year-old female with a past medical history of spontaneous dissection of the distal descending left artery (LAD) 6 years before. She presented to our hospital with a non-ST elevation myocardial infarction and a coronary angiogram showed a giant saccular aneurysm of the shaft of the left main coronary artery (LMCA). Given the risk of rupture and distal embolization, the heart team decided to go for a percutaneous approach. Based on a pre-interventional 3D reconstructed CT scan and guided by intravascular ultrasound, the aneurysm was successfully excluded with a 5 mm papyrus-covered stent. At 3-month and 1-year follow-up, the patient is still asymptomatic and repeat angiographies showed full exclusion of the aneurysm and the absence of restenosis in the covered stent.

Discussion

We describe the successful percutaneous IVUS-guided treatment of a giant LMCA shaft coronary aneurysm with a papyrus-covered stent with an excellent 1-year angiographic follow-up showing no residual filling of the aneurysm and no stent restenosis.

Coronary Arteries Aneurysms: A Case-Based Literature Review

Coronary artery aneurysm (CAA) is an abnormal dilatation of a coronary artery segment; those coronary artery aneurysms that are very large in size are defined as giant. However, a standardized dimension cut-off to define giant CAAs is still missing. The reported prevalence of coronary aneurysms in the population who underwent coronary angiography ranges from 0.3% to 5%, and often CAAs are found in patient with aneurysms in other sites, such as the ascending or abdominal aorta. In half of the cases an atherosclerotic etiology could be recognized; often, CAA is found in the context of acute coronary syndrome. Seldomly, CAA is found at the autopsy of patients who died due to sudden cardiac death. Currently, very few data exist about CAA management and their prognostic relevance; moreover, CAA treatment is still not clearly codified, but rather case-based. Indeed, currently there are no published dedicated studies exploring the best medical therapy, i.e., with antiplatelets or anticoagulant agents rather than an interventional approach such as an endovascular or surgical technique. In this review, through two clinical cases, the current evidence regarding diagnostic tools and treatment options of CAAs will be described.

Covered Stenting for a Large Coronary Artery Aneurysm With Adjacent Stenosis in a Poor Surgical Candidate

Coronary artery aneurysms (CAAs) are being increasingly diagnosed with the advent of coronary angiography, and their management depends on the clinical presentation, size, and etiology of the aneurysm. Small aneurysms are usually managed with covered stents, while surgical intervention is considered for large aneurysms. We present a challenging case of a large CAA with adjacent coronary artery stenosis managed with guide extension catheter-assisted covered stent deployment as the patient was not a good surgical candidate.

Unconventional treatment of a giant coronary aneurysm presenting as ST-elevation myocardial infarction: a case report

Background

The optimal treatment of aneurysmal or ectatic culprit vessels in the setting of acute myocardial infarction is still matter of debate, as revascularization with either percutaneous intervention or surgery is associated with low procedural success and poor outcomes.

Case summary

We report the case of a 55-year-old male patient, admitted for inferior ST-elevation myocardial infarction, who underwent successful percutaneous implantation of a micro-mesh self-expanding nitinol carotid stent in a right coronary aneurysm with intravascular ultrasonography measured diameter of 9 mm and massive thrombus apposition.

Discussion

The technical characteristics of the micro-mesh self-expanding nitinol carotid stent allow for adequate plaque coverage and good apposition even in large vessels, making this device particularly suitable for the treatment of coronary lesions with high thrombus burden, when severe coronary ectasia or aneurysms are present.

ePTFE-based biomedical devices: An overview of surgical efficiency

Polytetrafluoroethylene (PTFE) is a ubiquitous material used for implants and medical devices in general because of its high biocompatibility and inertness: blood vessel, heart, table jawbone, nose, eyes, or abdominal wall can benefit from its properties in case of disease or injury. Its expanded version, ePTFE is an improved version of PTFE with better mechanical properties, which extends its medical applications. A material as frequently used as ePTFE with these exceptional properties deserves a review of its main uses, developments, and possibility of improvements. In this systematic review, we examined clinical trials related to ePTFE-based medical devices from the literature. Then, we excluded all trials using ePTFE as a control to test other devices. ePTFE-coated stents, hemodialysis and bypass grafts, guided bone and tissue regeneration membranes, hernia and heart repair and other devices are reviewed. The rates of success using these devices and their efficiency compared to other materials used for the same purposes are reported. ePTFE appears to be more or just as efficient compared to them. Some success rates remain low, suggesting the need of improvement ePTFE for medical applications.

Multi-Vessel Coronary Artery Ectasia

Coronary artery ectasia is a relatively rare entity, especially when it involves the left main coronary artery. Furthermore, it is even more uncommon for such a disease process to involve multiple coronary arteries. Here we describe a case of a 78-year-old female who did not possess any of the common risk factors or vasculitic etiologies associated with coronary artery ectasia, who was found to have multi-vessel ectatic segments, including that of the left main coronary artery. This case illuminates the difficult decision making regarding stenting of the coronary arteries with ectatic segments and the decision to anticoagulate.

Outcomes of patients who undergo elective covered stent treatment for coronary artery aneurysms

BACKGROUND

Coronary artery aneurysms (CAA) are reported in up to 5% of patients undergoing coronary angiography. Treatment of CAAs with covered stents has been reported in several case reports, however there is limited evidence available on the effectiveness and safety of this interventional practice.

PURPOSE

To evaluate the current practice and outcomes of elective treatment of coronary artery aneurysms with covered stents.

METHODS

We conducted a systematic review of published case reports and case series of patients presenting with CAA that have been treated with covered stents in a non-emergency setting.

RESULTS

A total of 63 case reports and 3 case series were included in the final analysis comprising data from 81 patients. The treated CAA was situated in a native coronary artery in 92.6%, and in a saphenous vein graft in 7.4%. Procedural success was achieved in 95.1%. The types of stents used were mainly polytetrafluoroethylene (75.3%) and Papyrus (11.1%). In 11.0% of cases additional abluminal drug eluting stents (DES) and in 6.8% additional adluminal DES were implanted. After a mean follow up of 13.4 months overall major adverse cardiovascular events (MACE), mortality, myocardial infarction, stroke, stent thrombosis and target lesion revascularization were reported in 26.2, 0.0, 7.6, 0.0, 4.6 and 18.5% of cases, respectively.

CONCLUSIONS

The use of covered stents for elective treatment of CAA appears to be effective and reasonably safe. Nevertheless, it is associated with higher MACE rate, driven mainly by higher target lesion revascularization. Further studies, particularly in form of randomized trials and controlled registries are warranted to identify patients who might profit the most from this procedure.

Percutaneous Coronary Intervention in Coronary Artery Aneurysms; Technical Aspects. Report of Case Series and Literature Review

Coronary Artery Aneurysms (CAAs) in both symptomatic and asymptomatic patients are associated with poor long-term outcomes. The best treatment option for CAAs remains a subject of debate. The underlying pathology is not well understood, randomised controlled trials and supportive data are lacking and there is no consensus on treatment plan. The recommended therapies include medical management, percutaneous or surgical exclusion of the aneurysm or coronary artery bypass grafting surgery (CABG). Percutaneous coronary intervention (PCI) can be technically challenging even with a suitable anatomy, specifically in acute coronary syndrome (ACS). We report case series of CAAs presenting as ACS and focus on PCI treatment option.

Asymptomatic giant right coronary artery aneurysm in Kawasaki disease: A case report

Incidentally diagnosed giant coronary artery aneurysms (gCAA) exceeding 50 mm in diameter are extremely rare and carry increased risks of cardiovascular morbidity and mortality. Currently, surgery is the preferred treatment for such gCAA.

Clinical Outcomes After Implantation of Polyurethane-Covered Cobalt-Chromium Stents: Insights from the Papyrus-Spain Registry

BACKGROUND/PURPOSE

The main indication of covered stents (CS) is coronary artery perforation (CAP), but, they have been increasingly used in other scenarios. Data on the long-term follow-up of CS is limited, and no studies have been conducted specifically using new-generation polyurethane-covered cobalt-chromium Papyrus CS.

PURPOSE

to evaluate the clinical outcomes after hospital discharge of Papyrus CS and to compare their outcome after implantation in CAP or coronary artery aneurysms (CAA).

METHODS/MATERIALS

We evaluated the baseline clinical characteristics, lesion subsets, procedural features and the outcomes after initial discharge of Papyrus CS implanted in 17 high-PCI-volume centers.

RESULTS

127 Papyrus CS were implanted in 108 patients (68 ± 1 years; 82.8% male) admitted for stable coronary disease (32.3%), NSTEMI (42.4%) or STEMI (25.3%). The number of CS per patient was 1.2 ± 0.6 (diameter: 3.5 ± 1.7 mm; length: 18.5 ± 3.7 mm). Angiographic success rate was 96%. CS diameter was larger in CAA (CAP:3.04 ± 0.5 mm vs CAA:4.1 ± 2.7 mm; p = .022). Intracoronary imaging techniques were used more frequently in CAA (p < .0001). After a mean follow-up of 22 ± 16 months, the major cardiovascular adverse events (MACE) rate was 7.1% [cardiac death: 2%, Myocardial infarction: 5%, Target Lesion Revascularization: 5% and Stent Thrombosis (ST): 3%]. MACE rate was similar in CAP (7.7%) and CAA (7.1%) (p = .9). However, CAA showed a higher ST rate (CAP: 0% vs CA: 7.1%; p = .04).

CONCLUSION

After hospital discharge, clinical outcomes after Papyrus CS implantation are acceptable (considering the clinical scenario and compared with other treatment alternatives) with no significant differences in the MACE rate between those implanted in CAA or in CAP. However, CAA group showed a higher ST rate.

Very long-term outcome of coronary covered stents: a report from the SCAAR registry

AIMS

Covered stents are mostly used for coronary perforations with a high risk of early adverse events; however, their long-term outcome is unknown. The aim of this study was to elucidate the short- and long-term outcome of patients treated with covered stents compared to all other stented patients.

METHODS AND RESULTS

The Swedish national registries from 2005-2017 disclosed 265 patients who had received 366 covered stents. Their outcomes were compared to all other stented patients (197,948) who had received 320,784 stents. Compared to regular stents, covered stents showed significant differences (p<0.001) in the short and long term in relation to in-stent restenosis (ISR), target lesion revascularisation (TLR), re-infarction (MI), re-PCI and mortality, the rates of which were all higher. The higher mortality was concentrated within the first month, as a landmark analysis at that time point, adjusted for age and procedural indication, demonstrated no future difference in mortality (HR 1.02 [0.78-1.33], p=0.877). Stent thrombosis (ST) within one year was reported to be higher in covered stents than in other stents. However, no ST was reported in equine pericardial covered stents.

CONCLUSIONS

This observational study including the entire Swedish population shows that patients receiving covered stents have a significantly higher risk of all adverse events. Reassuringly, in the long term, mortality appears to be similar to that in other stented patients.

Outcome after new generation single-layer polytetrafluoroethylene-covered stent implantation for the treatment of coronary artery perforation

AIMS

Coronary artery perforation (CAP) is a rare but severe complication during percutaneous coronary intervention (PCI). Implantation of covered stents (CS) represents a potentially life-saving treatment. Concerns exist regarding limited efficacy and high stent thrombosis (ST) rates related to early generation CS. The aim of this study was to evaluate angiographic and clinical outcomes of patients with CAP treated with a new generation single-layer polytetrafluoroethylene (PTFE)-CS.

METHODS

Between May 2013 and November 2017, we identified a total of 61 patients who underwent implantation of 71 single layer PTFE-CS after CAP. We analyzed angiographic results at follow up (including binary angiographic restenosis [BAR] and late-lumen-loss [LLL]) and clinical outcomes in hospital and at follow up, including target lesion revascularization (TLR), cardiovascular-, and all-cause mortality, myocardial infarction (MI) and stent thrombosis (ST).

RESULTS

Procedural success was achieved in all but two patients (96.7%). Procedure related MI, occurred in 19 cases (31.1%), in hospital death occurred in five cases (8.2%). At follow-up, TLR occurred in 11 cases (18.0%), two patients (3.3%) died from non-cardiovascular cause, there was no case of MI or ST.

CONCLUSIONS

In this retrospective analysis, implantation of a new generation PTFE-CS, for the treatment of CAP showed high technical success rates. Although, periprocedural MI-and in-hospital-death rates remain not inconsiderable, new generation PTFE-CS showed favorable angiographic and clinical efficacy and high safety profile, especially with regard to thrombotic events.

Multiple coronary and cerebral aneurysms in a patient with chronic thromboangiitis

A 73-year-old man had multiple coronary aneurysms that resulted in acute myocardial infarction on the day before surgery for cerebral aneurysms. Emergent coronary angiography revealed that the lesion that caused the myocardial infarction was a distal left circumflex artery, and two huge coronary aneurysms were also found in the left circumflex artery. A two-stage treatment strategy was planned, including coronary aneurysm surgery, followed by cerebral aneurysm surgery. He underwent coronary artery aneurysmorrhaphy with closure of the ostia of the afferent and efferent arteries, and coronary artery bypass grafting with a saphenous vein graft applied to the left circumflex artery. The pathological findings suggested chronic thromboangiitis, as the inflammatory cells were observed to have infiltrated the coronary artery wall. The tissue remodeling of the aneurysmal wall indicated a positive response to tenascin C. We report a case of multiple coronary aneurysms, focusing on the pathological findings. <Learning objective: Only few reports have described coronary aneurysms related to inflammatory, atherosclerotic, and connective tissue diseases. This report describes the simultaneous occurrence of coronary and cerebral artery aneurysms, focusing on the histopathological findings. The patient's histopathological examination revealed a positive response to tenascin C, which suggested tissue remodeling of the aneurysmal wall and chronic thromboangiitis.>.

Intravascular Ultrasound-Guided Management of Proximal Left Anterior Descending Artery Aneurysm With Covered Stent - A Case Report

Coronary artery aneurysm is defined as the localized dilatation of a coronary artery segment more than 1.5 times the size of adjacent normal segments. The aneurysms of the coronary arteries are rare. Coronary aneurysms can be congenital or acquired. The majority are atherosclerotic in origin. The primary complication is myocardial ischemia or infarction, sudden cardiac death with rupture being rare. Some aneurysms are diagnosed incidentally in arteries other than the culprit artery. Treatment options include medical management with anticoagulation, percutaneous intervention with covered stents or surgery. We report a case of 67-year-old male who presented with acute coronary syndrome. Coronary angiogram showed a moderate size aneurysm of the proximal left anterior descending artery. This aneurysm was successfully managed percutaneously with a covered stent.

Three-vessel coronary artery aneurysmal disease complicated by multivessel thrombosis and cardiogenic shock: the saving role of intracoronary thrombolysis

The benefit of intracoronary thrombolytics in ST-elevation myocardial infarction (STEMI) is not well established. Mainstays of STEMI management include intravenous thrombolytics, percutaneous coronary interventions and surgical revascularisation. However, in cases of STEMI secondary to coronary artery aneurysmal disease (CAAD), standard treatment options may not be suitable due to high thrombus burden, perioperative risk and factors unique to each patient. Thus, STEMI management in CAAD can represent a therapeutically challenging clinical scenario. Here, we describe a patient with severe three-vessel CAAD complicated by multivessel thrombosis and cardiogenic shock for whom traditional management options including placement of haemodynamic support devices were not feasible. As an alternative measure, the patient was treated with intracoronary thrombolysis with remarkable clinical stabilisation and angiographic resolution of thrombosis. He remains clinically stable several years later without recurrent events. This case serves to demonstrate the potential lifesaving benefit of intracoronary thrombolysis in complicated multivessel CAAD.

Nonsurgical Management of a Giant Coronary Artery Aneurysm

Coronary artery aneurysms (CAAs) are rare dilations of arterial segments. These aneurysms are mostly caused by atherosclerosis. Due to the rarity of this condition, there are no official guidelines for its management; therefore, management is mainly based on case reports. We present a patient with a giant CAA in the left anterior descending artery who was treated medically. At 12-month follow-up,  he was asymptomatic and had no complications.  

Coronary covered stents

Covered stents offer an effective bail-out strategy in vessel perforations, are an alternative to surgery for the exclusion of coronary aneurysms, and have a potential role in the treatment of friable embolisation-prone plaques. The aim of this manuscript is to offer an overview of currently available platforms and to report results obtained in prior studies.

Coronary Artery Aneurysms: A Review of the Epidemiology, Pathophysiology, Diagnosis, and Treatment

Coronary artery aneurysms (CAAs) are uncommon and describe a localized dilatation of a coronary artery segment more than 1.5-fold compared with adjacent normal segments. The incidence of CAAs varies from 0.3 to 5.3%. Ever since the dawn of the interventional era, CAAs have been increasingly diagnosed on coronary angiography. Causative factors include atherosclerosis, Takayasu arteritis, congenital disorders, Kawasaki disease (KD), and percutaneous coronary intervention. The natural history of CAAs remains unclear; however, several recent studies have postulated the underlying molecular mechanisms of CAAs, and genome-wide association studies have revealed several genetic predispositions to CAA. Controversies persist regarding the management of CAAs, and emerging findings support the importance of an early diagnosis in patients predisposed to CAAs, such as in children with KD. This review aims to summarize the present knowledge of CAAs and collate the recent advances regarding the epidemiology, etiology, pathophysiology, diagnosis, and treatment of this disease.

Successful management of a giant unruptured mycotic coronary artery aneurysm after coronary angioplasty

Coronary artery stent infection has been reported with both bare metal stent and drug eluting stent and can present as mycotic coronary artery aneurysm, pseudoaneurysm, myocardial abscess, pericarditis or exudative effusion. Infection at the site of coronary stent implantation is rare and is believed to result typically from either direct stent contamination at the time of delivery or transient bacteraemia from access site. Introduction of drug-eluting stent (DES) has led to a marked reduction in the problem of in-stent restenosis across all patient subsets and lesions complexities. Recently, several case reports of pseudoaneurysm formation after DES implantation have been reported in the literature. We describe the successful surgical management of giant mycotic pseudoaneurysm of left anterior descending artery (LAD) presenting as fever of unknown origin. This report illustrates the importance of early detection and prompt management of these rare coronary pseudoaneurysms, which is a highly lethal condition.

Percutaneous exclusion of a rapidly enlarging left main coronary artery aneurysm using coils and an Amplatzer™ septal occluder

Coronary artery aneurysms (CAAs) are often an incidental finding amongst patients undergoing coronary angiography. Most CAAs are managed conservatively; rarely a larger CAA can lead to intramural thrombus formation and coronary artery embolization/obstruction even without the presence of significant stenosis. Despite these clinical implications, therapeutic options are limited to case reports and no clearly defined guidelines have been established for treatment. In this article, we present a unique case of a rapidly enlarging left main CAA, with no identifiable etiology that was treated with percutaneous exclusion via coil embolization and an Amplatzer™ septal occluder device. We also discuss existing literature, pathophysiology, and management options for CAAs. © 2016 Wiley Periodicals, Inc.

Chronic pericardial hematoma with suppression of the right ventricle: a rare complication of a coronary artery aneurysm

We present a case of a 67-year-old patient referred to our department with a pericardial mass lesion measuring 11 × 4 × 7.5 cm as diagnosed in computed tomography scan. The patient showed a history of progredient dyspnea. Video-assisted thoracoscopy as well as an explorative full sternotomy to resect the mass lesion had been performed at the referring hospital subsequently before admission to our department. Intermittent hemodynamic instability caused the procedure to stop and a transfer to the cardiothoracic surgery department, following which a resternotomy was performed. Inspection of the surgical site and subsequent intraoperative rapid section revealed an old organized and dense pericardial hematoma adherent to the right ventricle. The suspicion of covered coronary artery perforation led to an intraoperative coronary angiography, which revealed a large proximal coronary aneurysm of the right coronary artery and a subtotal stenosis of the circumflex branch. The hematoma could be removed with decompression of the right ventricle under cardiopulmonary bypass conditions. The further postoperative course was uncomplicated with retransfer to the referring hospital on the postoperative day 8.

Covered stents for the endovascular treatment of a direct carotid cavernous fistula : single center experiences with 10 cases

OBJECTIVE

Covered stent has been recently reported as an effective alternative treatment for direct carotid cavernous fistulas (DCCFs). The purpose of this study is to describe our experiences with the treatment of DCCF with covered stents and to evaluate whether a covered stent has a potential to be used as the first choice in selected cases.

METHODS

From February 2009 through July 2013, 10 patients underwent covered stent placement for a DCCF occlusion. Clinical and angiographic data were retrospectively reviewed.

RESULTS

Covered stent placement was performed for five patients primarily as the first choice and in the other five as an alternative option. Access and deployment of a covered stent was successful in all patients (100%) and total occlusion of the fistula was achieved in nine (90%). Complete occlusion immediately after the procedure was obtained in five patients (50%). Endoleak persisted in five patients and the fistulae were found to be completely occluded by one month control angiography in four. The other patient underwent additional coil embolization by a transvenous approach. Balloon inflation-related arterial dissection during the procedure was noted in two cases; healing was noted at follow-up angiography. One patient suffered an asymptomatic internal carotid artery occlusion noted seven months post-treatment.

CONCLUSION

Although endoleak is currently a common roadblock, our experience demonstrates that a covered stent has the potential to be used as the first choice in DCCF; this potential is likely to increase as experience with this device accumulates and the materials continue to improve.

Elastin-like recombinamer-covered stents: Towards a fully biocompatible and non-thrombogenic device for cardiovascular diseases

We explored the use of recently developed gels obtained by the catalyst free click reaction of elastin-like recombinamers (ELRs) to fabricate a new class of covered stents. The approach consists in embedding bare metal stents in the ELR gels by injection molding, followed by endothelialization under dynamic pressure and flow conditions in a bioreactor. The mechanical properties of the gels could be easily tuned by choosing the adequate concentration of the ELR components and their biofunctionality could be tailored by inserting specific sequences (RGD and REDV). The ELR-covered stents exhibited mechanical stability under high flow conditions and could undergo crimping and deployment without damage. The presence of RGD in the ELR used to cover the stent supported full endothelialization in less than 2weeks in vitro. Minimal platelet adhesion and fibrin adsorption were detected after exposure to blood, as shown by immunostaining and scanning electron microscopy. These results prove the potential of this approach towards a new and more effective generation of covered stents which exclude the atherosclerotic plaque from the blood stream and have high biocompatibility, physiological hemocompatibility and reduced response of the immune system.

Tissue responses to stent grafts with endo-exo-skeleton for saccular abdominal aortic aneurysms in a canine model

OBJECTIVE

We evaluated the effect of close contact between the stent and the graft on the induction of endothelial covering on the stent graft placed over an aneurysm.

MATERIALS AND METHODS

Saccular abdominal aortic aneurysms were made with Dacron patch in eight dogs. The stent graft consisted of an inner stent, a expanded polytetrafluoroethylene graft, and an outer stent. After sacrificing the animals, the aortas with an embedded stent graft were excised. The aortas were inspected grossly and evaluated microscopically.

RESULTS

The animals were sacrificed at two (n = 3), six (n = 3), and eight months (n = 2) after endovascular repair. In two dogs, the aortic lumen was occluded at two months after the placement. On gross inspection of specimens from the other six dogs with a patent aortic lumen, stent grafts placed over the normal aortic wall were covered by glossy white neointima, whereas, stent grafts placed over the aneurysmal aortic wall were covered by brownish neointima. On microscopic inspection, stent grafts placed over the normal aortic wall were covered by thin neointima (0.27 ± 0.05 mm, mean ± standard deviation) with an endothelial layer, and stent grafts placed over the aneurysmal aortic wall were covered by thick neointima (0.62 ± 0.17 mm) without any endothelial lining. Transgraft cell migration at the normal aortic wall was more active than that at the aneurysmal aortic wall.

CONCLUSION

Close contact between the stent and the graft, which was achieved with stent grafts with endo-exo-skeleton, could not enhance endothelial covering on the stent graft placed over the aneurysms.

Successful treatment of a ruptured spontaneous dissecting coronary artery pseudoaneurysm with a covered stent in a patient with cardiac tamponade

The rupture of spontaneous dissecting coronary artery pseudoaneurysms is rare, and no standard therapy has yet been established for this condition. This report describes a case of a ruptured spontaneous dissecting coronary artery pseudoaneurysm in a patient with cardiac tamponade that was successfully treated with emergent implantation of a covered stent.

The diagnosis and treatment of a mycotic coronary artery aneurysm: a case report

Aneurysms of the coronary arteries are rare and are usually associated with atherosclerosis in adults. Mycotic coronary artery aneurysms are exceedingly uncommon and are typically associated with systemic bacteremia, endocarditis, or septic emboli. Literature and data describing the management of mycotic coronary artery aneurysms are limited. This case describes the successful diagnosis of a large right coronary artery aneurysm by transesophageal echocardiogram as well as the successful management of the aneurysm.

Optical coherence tomographic observations of polytetrafluoroethylene-covered sirolimus-eluting coronary arterial stent

The aim of this study was to evaluate neointimal coverage obtained using a new method of polytetrafluoroethylene-covered stent (PCS) implantation combined with underlying longer sirolimus-eluting stent (SES) implantation using optical coherence tomography. Nine patients were enrolled in this study, including patients with coronary artery perforations, original coronary aneurysms, and acquired coronary aneurysms after drug-eluting stent implantation. All patients were first treated with long SES implantation and then with focal PCS implantation. Postprocedural and follow-up angiographic and optical coherence tomographic examinations were performed in all patients, and intravascular ultrasound was performed in 5 patients. All patients were asymptomatic during follow-up, without recurrent angina. There was no stent-edge or stent-segment binary restenosis. Values of late loss for proximal SES segments, PCS segments, and distal SES segments were similar (0.09, 0.07, and 0.04 mm, respectively, p = 0.8113). The mean neointimal thickness of PCS was less than that of proximal and distal SES. However, no malapposed cross sections or uncovered cross sections were found in PCS segments compared with SES segments (p = 0.0011). In conclusion, the combination of PCS and underlying longer SES implantation can offer better angiographic follow-up results. High-resolution optical coherence tomography provided convincing proof of full neointimal coverage of PCS. This new method of combined PCS and SES implantation may be a better choice compared with direct PCS implantation in certain clinical settings.

Stenting for huge coronary artery aneurysm and stenosis in a patient with Behçet's disease presenting with non-ST segment elevation myocardial infarction

Coronary artery aneurysms in patients with Behçet's disease are rare and associated with fatal complications. Covered stents have been used in the management of coronary aneurysms but not in patients with Behçet's disease. We are reporting a rare case of Behçet's disease, admitted with non-ST segment elevation myocardial infarction, whose coronary angiogram revealed huge aneurysm involving proximal left anterior descending artery followed by severe stenosis. The stenosis was treated by drug-eluting stent and the aneurysm was successfully sealed with a covered stent. He remained asymptomatic at 3-month follow-up and repeat angiogram showed patent stents. <Learning objective: There is no consensus upon the management of coronary artery aneurysm in a patient with Behçet's disease presenting with acute myocardial infarction. Sealing of aneurysm with covered stent and managing stenosis with drug-eluting stent can also be used for management in these patients with adequate use of immunosuppressant and anticoagulant.>.

A right coronary artery saccular aneurysm leading to an embolic myocardial infarction during diagnostic cardiac catheterization: A case report

Coronary artery aneurysms are localized dilatations greater than 1.5 times the diameter of the adjacent segments. These rarely seen abnormalities may lead to serious life-threatening complications such as myocardial infarction, coronary perforation and death. Here, we present a case of periprocedural thromboembolic inferior myocardial infarction arising from a proximal right coronary artery saccular aneurysm during a diagnostic coronary angiography in a stable 70-year-old patient.

Coil embolization of left coronary artery pseudoaneurysms arising as a complication of percutaneous coronary intervention

Coronary aneurysms and pseudoaneurysms have been described as rare complications following percutaneous coronary intervention (PCI). There is limited data available on the optimal treatment strategy for these conditions. Use of noninvasive techniques including covered stents has been described as a potential therapeutic strategy. We report a case of percutaneous coil embolization of two enlarging left anterior descending pseudoaneurysms arising as a complication of PCI.

[Noninvasive imaging techniques to study coronary artery aneurysms]

Given the growing evidence about the use of membrane-covered stents to treat coronary artery aneurysms, it is fundamental to know the exact anatomy of the aneurysm to enable patients to be selected correctly. Invasive heart catheterization has limitations for diagnostic purposes and can underestimate the size of the aneurysm. In this article, we review the noninvasive diagnostic imaging techniques for the study of coronary artery aneurysms, illustrating the usefulness of each technique.

A 15-cm aneurysm of the right coronary artery presenting as a pericardial cyst

We report an unusual case of a giant right coronary artery aneurysm, measuring 15 cm in diameter, in a 76-year old woman. The aneurysm was initially identified when the patient was investigated for signs of congestive cardiac failure with a computed tomography scan of her thorax; at this stage, the lesion was misdiagnosed as a large pericardial cyst. The aneurysm was successfully excised at surgery and her heavily diseased right coronary artery was secured with a saphenous vein graft.