Covered stent for closure of symptomatic plexus-like coronary fistula

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.

Preparation of a Microporous Polyurethane Film with Negative Surface Charge for siRNA Delivery via Stent

Polyurethane (PU) and polyethylene glycol (PEG) were used to prepare a porous stent-covering material for the controlled delivery of small interfering RNA (siRNA). Microporous polymer films were prepared using a blend of polyurethane and water-soluble polyethylene glycol by the solution casting method; the PEG component was extracted in water to make the film microporous. This film was dipped in 2% poly(methyl methacrylate-co-methacrylic acid) solution to coat the polymer film with the anionic polyelectrolyte. The chemical components of the film surface were characterized by Fourier Transform Infrared (FTIR) spectroscopy and its structural morphology was examined by scanning electron microscopy (SEM). The effect of the negatively charged surface after attachment of a fluorescein isothiocyanate- (FITC-) labeled siRNA-polyethyleneimine complex onto the microporous polyurethane film and the controlled release of the complex from the film was investigated by fluorescence microscopy. Fluorescence microscopy showed the PU surface with intense fluorescence by the aggregates of the FITC-labeled-siRNA-PEI complex (measuring up to few microns in size); additionally, the negatively charged PU surface revealed broad and diffuse fluorescence. These results suggest that the construction of negatively charged microporous polyurethane films is feasible and could be applied for enhancing the efficiency of siRNA delivery via a stent-covering polyurethane film.

Congenital coronary artery fistulas complicated with pulmonary hypertension: Analysis of 211 cases

AIM

To compare the behavior of pulmonary hypertension (PHT) associated with coronary artery fistulas (CAFs) between the Asian and Caucasian subjects.

METHODS

CAFs may be complicated with PHT secondary to left-to-right shunt. Literature review limited to the English language. A total of 211 reviewed patients were collected. Of those, 111 were of Asian and 100 were of Caucasian ethnic origin. The mean age of the Asian and the Caucasian groups of patients were 48.9 (range 19-83) and 49.9 years (range 16-85), respectively. In both groups, right heart catheterization was the most commonly (95%) used method for determining pulmonary artery pressure.

RESULTS

From all of the reviewed subjects, PHT was found in 49 patients (23%), of which 15 were Asian and 34 were Caucasian. In 75% of PHT subjects, mild to moderate PHT was reported and 76% of the fistulas had a vascular mode of termination. Treatment was surgical in 61%, followed by percutaneous therapeutic embolization (27%) and finally conservative medical management in 12% of PHT subjects. PHT was associated with a slight female gender predominance. The majority demonstrated mild to moderate PHT. PHT was reported more frequent in the Caucasian compared with the Asian ethnicity group. The majority of fistulas in patients with PHT had a vascular mode of termination. The results of this review are intended to be indicative and require cautious interpretation.

CONCLUSION

The likelihood for a CAF patient to develop PHT is presented when possessing the following features, with a Caucasian female having a fistula with a vascular mode of termination.

Percutaneous closure of coronary artery fistula: long-term follow-up results

Introduction

Coronary artery fistula consists of abnormal congenital connections between a coronary artery and cardiac chambers, a coronary vessel or an intrathoracic vessel that can be complicated by intracardiac shunts, endocarditis, myocardial infarction, or coronary aneurysms. Recent reports have emphasized the efficacy of percutaneous transcatheter techniques as an alternative to surgical closure, but the reported experience is relatively limited.

Aim

To assess angiographic outcomes in a series of 20 patients who underwent transcatheter closure of coronary artery fistula.

Material and methods

We evaluated all patients presenting with significant coronary artery fistula and undergoing transcatheter closure with coils and a vascular plug between March 2008 and June 2012.

Results

There were 20 patients (14 men; mean age: 53 ±8 years) with coronary artery fistula. Fistula diameter ranged from 4 to 12 mm; an average of three coils were used in the percutaneous procedure. Post-deployment angiograms demonstrated complete occlusion in all patients. The patients were followed up for 4 ±1.6 years. The control coronary computed tomographic angiography was performed in the sixth month and no patients had recanalization of the embolized vessel.

Conclusions

Percutaneous closure of coronary artery fistula is a safe and effective treatment modality.

Diagnostic and therapeutic approach of congenital solitary coronary artery fistulas in adults: Dutch case series and review of literature

BACKGROUND

Coronary artery fistulas (CAFs) are infrequent anomalies, coincidentally detected during coronary angiography (CAG).

AIM

To elucidate the currently used diagnostic imaging modalities and applied therapeutic approaches.

MATERIALS AND METHODS

Five Dutch patients were found to have CAFs. A total of 170 reviewed subjects were subdivided into two comparable groups of 85 each, treated with either percutaneous 'therapeutic' embolisation (PTE group) or surgical ligation (SL group).

RESULTS

In our series, the fistulas were visualised with several diagnostic imaging tests using echocardiography, multidetector computed tomography, and CAG. Four fistulas were unilateral and one was bilateral; five originated from the left and one originated from the right coronary artery. Among the reviewed subjects, high success rates were found in both treatment groups (SL: 97% and PTE: 93%). Associated congenital or acquired cardiovascular disorders were frequently present in the SL group (23%). Bilateral fistulas were present in 11% of the SL group versus 1% of the PTE group. The fistula was ligated surgically in one and abolished percutaneously in another. Medical treatment including metoprolol was conducted in two, and watchful waiting follow-up was performed in one.

CONCLUSIONS

Several diagnostic imaging techniques are available for assessment of the anatomical and functional characteristics of CAFs.

Transcatheter closure of coronary artery fistula using Guglielmi detachable coil

Background

Coronary artery fistula (CAF) is a rare anomaly. Transcatheter CAF closure has been introduced using various materials, but only few data are available on the Guglielmi detachable coil (GDC). The advantage of using GDC for transcatheter CAF closure is more controllable, therefore much safer when compared to other coils. This report is about our experience in transcatheter closure of CAF using fibered GDC in our hospital.

Methods & Results

From 2002 to 2007, there were 10 patients with CAFs (age range: 28 to 56 year-old, 7 males) who underwent transcatheter CAF closure. There were a total of 19 CAFs which originated from right coronary (n = 5), left circumflex (n = 3), left anterior descending artery (n = 10) and left main trunk (n = 1). Median number of coil deployment for each fistula was 3 (range: 1 to 6). The pulmonary artery was the most common site of the distal communication of CAFs (n = 14), followed by right atrium (n = 3), left atrium (n = 1) and left ventricle (n = 1). Immediate coronary angiography after GDC deployment revealed no residual shunt in 12 (63.2%) CAFs, significant reduction of the flow in 5 (26.3%), while 2 (10.5%) could not be closed due to small size. Nine (90%) patients underwent a repeated angiography within 3 to 8 months. Among 12 CAFs that were occluded immediately post-deployment, there were 2 CAFs with insignificant residual flow. Among 6 CAFs with significantly decreased flow immediately post-deployment, 2 were occluded totally in the follow-up angiography. In total, 12 (70.5%) CAFs were occluded completely and 5 (29.5%) CAFs still had insignificant residual flow, which did not need any additional coil deployment. During a mean follow up of 4.3 ± 0.7 year, all patients remained symptom and complication free.

Conclusions

The fibered GDC is a safe and effective method for percutaneous closure of the CAFs.

Gender-related differences in octogenarians with congenital coronary artery fistula: a report of two cases and a review

AIM

To highlight gender-related differences in octogenarians with a congenital coronary artery fistula (CAF).

MATERIALS AND METHODS

We present two elderly female patients with a congenital fistula, a septuagenarian and a nonagenarian, and review the world literature between 1954-2010.

RESULTS

The septuagenarian patient presented with easy fatigability and the nonagenarian patient with acute myocardial infarction contralaterally to the fistula. Coronary angiography (CAG) demonstrated a coronary-pulmonary artery fistula (CPF). The nonagenarian patient underwent percutaneous coronary intervention of the right coronary artery. CAG revealed a CPF associated with a huge multiple aneurysmal formation. Data from 57 mainly symptomatic patients with a mean age of 75.3 years (range 70-87 years) were collected. The cohort was subdivided into female (mean age 84.3 years) and male (mean age 75.2 years) subgroups and compared with each other. Multi-origin (bilateral and multilateral) was prevalent in females, 40% versus 12% in males. Aneurysmal formation was found in females and males in 40% and 18%, respectively. Ethnicity was 65% Caucasian and 35% Asian. Multi-origin fistulas were prevalent in the Asian (45%) compared with the Caucasian (11%) subset.

CONCLUSIONS

A septuagenarian and a nonagenarian female patient with congenital CAF are presented. On reviewing the literature, important differences were found between elderly females and males with congenital CAF.

Congenital solitary coronary artery fistulas characterized by their drainage sites

Last centuries have witnessed tremendous sophistication and progress in the detection, diagnosis and treatment of coronary artery fistulas (CAFs). In many countries, CAFs were reported to be visualized and treated using several imaging techniques and different management strategies. Reports from nearly all continents of the globe have contributed to the description of CAFs, not only in Asia and Europe but also throughout North and Latin America. However, these reports have to be cautiously analyzed as many of them were published as a case report and careful interpretation is warranted due to possible publication bias. A literature search was performed using PubMed search interface to select papers dealing with congenital CAFs in adult population between 2000-2009. A total of 233 subjects were collected, and analysed according to their drainage site and treatment modality. They were divided into two subgroups: percutaneous transluminal embolization group (PTE group, n = 122) and surgical ligation group (SL group, n = 111). In the SL group, atherosclerotic coronary artery disease (19%) and associated congenital lesions (23%) were more prevalent compared with the PTE group (9% and 8%), respectively. Infective endocarditis was more frequently seen in the SL group besides syncope, congestive heart failure and hemopericardium. In both groups multimodality diagnostic workup composed of several non-invasive and invasive imaging techniques for fistula visualization were performed and drainage sites into the different cardiac chambers and intrathoracic great vessels were similarly distributed in the two groups.