Coil embolization of coronary artery fistulas. A single-centre experience

Left Coronary Artery to Pulmonary Trunk Fistula: Two Case Reports With Literature Review

Coronary artery fistulas (CAFs) are abnormal communication between coronary arteries and the pulmonary trunk or with adjacent heart structures. Coronary pulmonary artery fistulas (CPAFs) can be congenital or acquired. Mostly, CAFs are found as incidental findings on angiographic evaluation. The management of CPAFs varies from case to case depending on size, anatomical location, patient's clinical presentation, and presence of coronary steal phenomenon. We present two cases of CPAFs; one of them had coronary steal phenomena at a young age with no past medical history of coronary artery disease, and the patient underwent transcatheter coil embolization to close the fistula. In other cases, a fistulous connection between the left anterior descending (LAD) and the pulmonary trunk was found incidentally on computed tomography (CT) of the heart and based on a small-sized fistula and symptomatic improvement, the patient was discharged with conservative management. CPAFs are rare cardiac anomalies but can give rise to severe hemodynamic complications, so this should be a part of the initial differential diagnosis if the patient does not have significant coronary artery disease. Percutaneous closure or surgical correction is indicated if the patients are symptomatic or have secondary complications.

Coronary-Pulmonary Artery Fistula Repair With Coil Embolization: A Single Center Experience

Coronary-pulmonary artery fistulas (CPF) are a rare malformation that is often asymptomatic but can be associated with dyspnea, angina, palpitation, dizziness, and syncope. Trans-catheter closure (TCC) with coil embolization is gaining prominence relative to surgical closure due to lower complications; however, there is a paucity of literature on the closure of CPFs with TCC. Here, we demonstrate a case series on the closure of a left anterior descending (LAD) artery to pulmonary artery (PA) fistula by advancing a guideliner into the coronary artery up to the origin of the coronary fistula in order to provide support for the advancement of the microcatheter and coil delivery.

The characteristics of coronary-pulmonary artery fistulas and the effectivity of trans-catheter closure: a single center experience

Background

Due to the low prevalence, the optimal treatment strategy of coronary-pulmonary artery fistula (CPF) remains unclear, and there are no established therapeutic guidelines available. The purpose of this study is to investigate the characteristics of CPF, and evaluate the effectivity of trans-catheter closure (TCC) for CPFs.

Methods

Patients with CPFs were retrospectively reviewed and enrolled according to the inclusion criteria. The data of clinical manifestations, physical signs, electrocardiogram (ECG), echocardiography, coronary CTA, coronary angiography and intervention procedure were collected. The telephone follow-up was conducted to evaluate the prognosis.

Results

The most common presenting complaint was dyspnea (n=21, 48.84%), followed by chest pain (n=10, 23.36%), palpitation (n=6, 13.95%), dizziness (n=3, 6.98%), and syncope (n=3, 6.98%). Most patients were coupled with single fistula (n=17, 39.53%) or two fistulas (n=23, 53.49%). Thirty fistulas (41.67%) involved the left anterior descending (LAD) artery, 28 fistulas (38.89%) involved the right coronary, 9 fistulas (12.50%) involved the left main trunk, and 5 fistulas (6.94%) involved the circumflex branch. Most of the fistulous tracts originated within the proximal one-third of the coronary arteries, only 6 fistulous tracts (8.33%) originated from the distal segment of the coronary arteries. The size of fistulas arranged from 1 mm to 8 mm, with an average of 3.45 mm. Thirty-five patients (81.40%) with 63 fistulas (87.50%) were successfully treated by percutaneous transcatheter closure. Thirty-eight patients accepted the 6-month follow-up, 36 patients (94.74%) were asymptomatic and 2 patients (5.26%) with palpitation. In conclusion, patients with more fistulas, larger fistula diameter and more severe left-to-right shunt are always coupled with more obvious clinical manifestations. The trans-catheter coil embolization is an effective method for the closure of CPFs.

Conclusions

patients with more fistulas, larger fistula diameter and more severe left-to-right shunt are always coupled with more obvious clinical manifestations. The trans-catheter coil embolization is an effective method for the closure of CPFs.

The molecular mechanism of contrast-induced nephropathy (CIN) and its link to in vitro studies on iodinated contrast media (CM)

Iodinated contrast media (iodinated CM) have increased ability to absorb x-rays and to visualize structures that normally are impossible to observe in a radiological examination. The use of iodinated CM may destory renal function, commonly known as contrast-induced nephropathy (CIN), which can result in acute renal failure (ARF). This review article mainly focuses on the following areas: (1) classifications of iodinated CM: ionic or non-ionic, high-osmolarity contrast media (HOCM), low-osmolarity contrast media (LOCM) and iso-osmolarity contrast media (IOCM); (2) an introduction to the physical and chemical properties of the non-ionic iodinated CM; (3) the management of anaphylactic reaction by iodinated CM; (4) a suggested single injection of adult doses and maximum dose for non-ionic iodinated CM; (5) the molecular mechanism of contrast-induced nephropathy (CIN); (6) In vitro studies on iodinated CM. Based on above information, this review article provide an insight for understanding the drug safety of iodinated CM.

Transcatheter Closure of Coronary Artery Fistulae: Considerations and Approaches Based on Fistula Origin

OBJECTIVES

To investigate technical approaches for transcatheter closure of coronary artery fistula based on anatomic type of the fistula.

BACKGROUND

The variability in coronary artery fistulae (CAF) anatomy that necessitates different transcatheter closure (TCC) approaches has not been well documented.

METHODS

Records of patients with CAF who underwent TCC at 2 centers were reviewed for technical details and procedural outcome. CAF were classified as proximal and distal. TCC approaches employed were arterio-venous or arterio-arterial loop, retrograde arterial, and antegrade venous.

RESULTS

Eighteen patients with CAF, mean age 12.6 years (0.07-60), 11 male (61%), underwent TCC. All CAF drained predominantly into the right side of the heart. Types of CAF were proximal in 15 and distal in 3 patients. CAF calibers were large in 7, medium in 9, and small in 2 patients. The arterio-venous loop approach was used in the majority of the cases (11 patients) and the CAF size were medium to large. The retrograde arterial approach was used in 4; of these, 3 patients had small to medium sized CAF. In 2 patients with long tortuous CAF an antegrade venous approach was employed. TCC was successful in 17 of the 18 patients (94.4%). There were no peri-procedural deaths or vascular complications.

CONCLUSIONS

This study documents transcatheter closure approaches for CAF and device selection based on fistula origin. The choices of TCC technique and device selection vary, and are primarily determined by the heterogeneous anatomic characteristics of the fistulae.

Side effects of radiographic contrast media: pathogenesis, risk factors, and prevention

Radiocontrast media (RCM) are medical drugs used to improve the visibility of internal organs and structures in X-ray based imaging techniques. They may have side effects ranging from itching to a life-threatening emergency, known as contrast-induced nephropathy (CIN). We define CIN as acute renal failure occurring within 24-72 hrs of exposure to RCM that cannot be attributed to other causes. It usually occurs in patients with preexisting renal impairment and diabetes. The mechanisms underlying CIN include reduction in medullary blood flow leading to hypoxia and direct tubule cell damage and the formation of reactive oxygen species. Identification of patients at high risk for CIN is important. We have reviewed the risk factors and procedures for prevention, providing a long list of references enabling readers a deep evaluation of them both. The first rule to follow in patients at risk of CIN undergoing radiographic procedure is monitoring renal function by measuring serum creatinine and calculating the eGFR before and once daily for 5 days after the procedure. It is advised to discontinue potentially nephrotoxic medications, to choose radiocontrast media at lowest dosage, and to encourage oral or intravenous hydration. In high-risk patients N-acetylcysteine may also be given.

Giant coronary artery fistula

Giant coronary artery fistula is rare. We describe the diagnostic work-up and surgical management of a 55-year-old woman who presented with congestive heart failure caused by a giant coronary artery fistula from the left circumflex artery to the coronary sinus.

A rare combination of the left circumflex coronary artery fistula connecting a dilated coronary sinus with persistent left superior vena cava and multiple arteriovenous fistulae

Coronary artery fistula (CAF) is an abnormal communication between an epicardial coronary artery and a cardiac chamber, major vessel or other vascular structures. This report presents a rare case of CAF in which a dilated left main trunk and proximal circumflex coronary artery are connected to a dilated coronary sinus. There were also two other fistulae and persistent left superior vena cava. The coronary fistula was managed conservatively.

Successful percutaneous coil embolization of a large and tortuous coronary artery to pulmonary artery fistula

We herein report the case of a 73-year-old woman with a large and tortuous coronary artery to pulmonary artery fistula treated with percutaneous coil embolization. The patient was hospitalized due to unstable angina with an elevated serum troponin-T level. Coronary angiography revealed no significant atherosclerotic stenosis, with a large and tortuous coronary artery to pulmonary artery fistula originating from the proximal portion of the left anterior descending artery. We successfully performed percutaneous coil embolization of the fistula. In this case, 320-slice multidetector computed tomography played a pivotal role in the diagnosis and percutaneous intervention.

Current characteristics of congenital coronary artery fistulas in adults: A decade of global experience

AIM

To describe the characteristics of coronary artery fistulas (CAFs) in adults, including donor vessels and whether termination was cameral or vascular.

METHODS

A PubMed search was performed for articles between 2000 and 2010 to describe the current characteristics of congenital CAFs in adults. A group of 304 adults was collected. Clinical data, presentations, diagnostic modalities, angiographic fistula findings and treatment strategies were gathered and analyzed. With regard to CAF origin, the subjects were tabulated into unilateral, bilateral or multilateral fistulas and compared. The group was stratified into two major subsets according to the mode of termination; coronary-cameral fistulas (CCFs) and coronary-vascular fistulas (CVFs). A comparison was made between the two subsets. Fistula-related major complications [aneurysm formation, infective endocarditis (IE), myocardial infarction (MI), rupture, pericardial effusion (PE) and tamponade] were described. Coronary artery-ventricular multiple micro-fistulas and acquired CAFs were excluded as well as anomalous origin of the coronary arteries from the pulmonary artery (PA).

RESULTS

A total of 304 adult subjects (47% male) with congenital CAFs were included. The mean age was 51.4 years (range, 18-86 years), with 20% older than 65 years of age. Dyspnea (31%), chest pain (23%) and angina pectoris (21%) were the prevalent clinical presentations. Continuous cardiac murmur was heard in 82% of the subjects. Of the applied diagnostic modalities, chest X-ray showed an abnormal shadow in 4% of the subjects. The cornerstone in establishing the diagnosis was echocardiography (68%), and conventional contrast coronary angiography (97%). However, multi-slice detector computed tomography was performed in 16%. The unilateral fistula originated from the left in 69% and from the right coronary artery in 31% of the subjects. Most patients (80%) had unilateral fistulas, 18% presented with bilateral fistulas and 2% with multilateral fistulas. Termination into the PA was reported in unilateral (44%), bilateral (73%) and multilateral (75%) fistulas. Fistulas with multiple origins (bilateral and multilateral) terminated more frequently into the PA (29%) than into other sites (10.6%) (P = 0.000). Aneurysmal formation was found in 14% of all subjects. Spontaneous rupture, PE and tamponade were reported in 2% of all subjects. In CCFs, the mean age was 46.2 years whereas in CVFs mean age was 55.6 years (P = 0.003). IE (4%) was exclusively associated with CCFs, while MI (2%) was only found in subjects with CVFs. Surgical ligation was frequently chosen for unilateral (57%), bilateral (51%) and multilateral fistulas (66%), but percutaneous therapeutic embolization (PTE) was increasingly reported (23%, 17% and 17%, respectively).

CONCLUSION

Congenital CAFs are currently detected in elderly patients. Bilateral fistulas are more frequently reported and PTE is more frequently applied as a therapeutic strategy in adults.

Successful percutaneous coil embolization of coronary-pulmonary, -carotid, and -internal mammary artery fistulas

We herein describe a 57-year-old man with coronary-pulmonary artery fistulas that had abnormal connections between the left common carotid artery and the left internal mammary artery. The patient was treated with percutaneous coil embolization using antegrade (via the coronary artery) and retrograde (via the pulmonary artery) approaches. Coronary artery fistulas have diverse anatomical variations, and it is important to thoroughly evaluate the anatomy before beginning any mode of treatment, surgical or endovascular. In the case reported herein, multislice computed tomography played a pivotal role in the preprocedure evaluation.

Recognition and Absorption of the Water-soluble X-ray Contrast Medium Iodixanol using Molecularly Imprinted Polymers for Biomedical Applications

This work presents the study on the recognition and absorption of the water-soluble X-ray contrast medium iodixanol in aqueous solution using synthetic molecularly imprinted polymers (MIPs). A non-covalent imprinting technique was applied to prepare iodixanol-imprinted polymers using 4-vinylpyridine as the functional monomer and ethylene glycol dimethacrylate as the cross-linker. The effects of quantity of iodixanol templates, the crosslink density, and the solvent were studied in terms of the binding capacity and imprint effect of the polymers. UV-vis spectrometric analysis shows that the highest binding capacity achieved is 284 mg iodixanol per gram of dry polymer, which is 8.8 times higher than the binding capacity of the non-imprinted control polymers (NIPs). SEM and BET surface analysis have also been performed to investigate the effect of morphology and porosity on the binding capacities of polymers.

A case of type I dual left anterior descending coronary to pulmonary artery fistula

We report a case of Type I dual left anterior descending coronary artery (LAD) giving rise to a pulmonary artery fistula via a short LAD branch, causing symptoms of typical angina. This rare coronary artery anomaly is importance to classify; it shows features of both intrinsic coronary artery anatomy anomaly and coronary drainage anomaly.