Evaluation of Efficacy of 64-Slice Multidetector Computed Tomography in Patients With Congenital Coronary Fistulas:

Coronary Artery Fistula: A Diagnostic Dilemma

Coronary artery fistula (CAF), although one of the rare coronary anomalies, is becoming increasingly more detectable in the recent years due to advancements in cardiac diagnostic imaging. Its long-term prognostic implications and importance for the cardiovascular system remain a dilemma for cardiologists and patients. Based on a variety of haemodynamic symptoms and complications, cardiologists must be aware of the characteristics of CAF and the diagnostic importance of multi-slice CT in evaluation, pre-procedural management and follow-up. Both surgical and percutaneous options are available for symptomatic patients or those with complications, while management of asymptomatic CAF remains a viable alternative.

Steal and strain: A case of coronary artery fistula presenting with coronary steal syndrome and underlying bronchiectasis

BACKGROUND

Coronary artery fistula is a relatively rare disorder with an incidence rate of 0.05-0.9%, and the majority of fistulae are detected incidentally. Most coronary artery fistulae are congenital, and the acquired variant is very rare. Herein, we present a possible acquired coronary artery to pulmonary artery fistula, most likely secondary to bronchiectasis in the adjacent lung. We will analyze the hemodynamic significance of the fistula in this case and also seek to understand the outcomes of various treatment modalities.

CASE PRESENTATION

A 56-year-old male patient presented with hypoxemia secondary to acute pulmonary edema during a hypertensive emergency. He developed myocardial ischemia after treatment with diuretics and nitroglycerin, due to shunting of blood from the right coronary artery to the right lower lobe branch of the right pulmonary artery, via the fistula. This resulted in coronary steal syndrome. Coronary angiogram confirmed the fistula connecting the right coronary artery to the right lower lobe branch of the right pulmonary artery. An attempt at coil embolization was unsuccessful due to the inability to advance the microcatheter beyond the fistula.

DISCUSSION

The majority of coronary artery fistulae are asymptomatic as they are hemodynamically not significant and are incidentally detected by coronary angiography, CT angiogram, echocardiogram or multi-detector row computed tomography (MDCT) with 3D reconstruction. The development of congenital fistula can be explained by the Hackensellner involution-persistence hypothesis, but the anatomy in this case and the bronchiectasis in the part of the lung adjacent to the fistula makes an acquired cause very likely due to local inflammation and the age of patient at initial diagnosis. An initial diagnosis of bronchiectasis was made at age 51, which was 5 years prior to the detection of the coronary artery fistula in this patient. Symptoms have been described mostly in the elderly and include chest pain, dyspnea, fatigue, syncope, and palpitations. Such symptomatic fistula should be treated either by percutaneous transluminal embolization or surgical ligation.

CONCLUSION

This is a unique case of acquired coronary to pulmonary artery fistula in the setting of bronchiectasis in a patient in which PTE was attempted and failed. More research is required to understand the pathophysiology of acquired fistula. The decision regarding the method of closure should be individualized and decided on a case by case basis.

Coronary-pulmonary fistula with common sac: An uncommon variant

A 68-year-old male patient presented with chief complaints of chest pain and dyspnea on exertion. On physical examination, his pulse was regular at 82 bpm and blood pressure was 140/80 mmHg. Resting electrocardiography (ECG) was within normal limit and chest X-ray also did not reveal any significant abnormality. Routine blood investigations were unremarkable; transthoracic echocardiography also did not show any significant abnormality. Catheter coronary angiography revealed severe triple vessel disease and showed possibility of coronary artery fistula. Computed tomography (CT) coronary angiography showed three aberrant branches arising from right and left coronary arteries forming a sac which subsequently opened into the main pulmonary artery.

Characteristics of Coronary Artery to Pulmonary Artery Fistula on Coronary Computed Tomography Angiography

OBJECTIVE

The aim of the study was to evaluate the characteristics of coronary artery-to-pulmonary artery fistula (CPAF) found by coronary computed tomography (CT) angiography.

METHODS

Among 10,121 cases of coronary CT angiography performed for 7 years, we found 32 cases of CPAF. We retrospectively evaluated the demographics, clinical symptoms, and anatomical characteristics such as the origin, number of origins, course, opening site of the fistula, and the presence of aneurysmal changes (defined as dilatation 1.5 times the diameter of the origin). We also categorized the fistula openings according to size compared with that of the proximal left anterior descending coronary artery.

RESULTS

The patients were 14 men and 18 women with a mean (range) age of 56.5 (34-86) years. Nineteen patients had no related symptoms, and the other 13 patients had symptoms such as angina, chest discomfort, palpitations, or shoulder pain. Among these patients, 2 patients were diagnosed with coronary artery disease. The origins of CPAF were single (n = 15, 46.9%) or multiple (n = 17, 53.1%). The CPAFs arose most commonly from the conus branch of the right coronary artery (n = 20, 62.5%) and proximal left anterior descending (n = 17, 53.1%). All CPAFs coursed anteriorly to the main pulmonary artery and drained into the anterolateral aspect. Twenty-five patients (78.1%) exhibited aneurysmal changes. The openings were small in 13 (40.6%), medium in 13 (40.6%), and large in 6 (18.8%) patients.

CONCLUSIONS

More than half of patients with CPAF had no related symptoms. Coronary artery-to-pulmonary artery fistula may have a single origin or multiple origins. All of the CPAFs coursed anteriorly to the main pulmonary artery and drained into the anterolateral aspect; the CPAFs identified here frequently exhibited aneurysmal changes.

MDCT of congenital coronary artery fistulas

OBJECTIVE

The purpose of this article is to describe the evaluation of congenital coronary artery fistulas (CAFs) with MDCT angiography with ECG gating (MDCTA), including the clinical manifestations, scanning techniques, differential diagnosis, and other imaging methods that may be used.

CONCLUSION

Congenital CAFs are rare coronary artery anomalies of termination. MDCTA is a first-line modality for pretreatment planning, and imaging findings should be recognized because CAFs may be detected incidentally.

Coronary arteriovenous fistulae: a review

Coronary arteriovenous fistulae are a coronary anomaly, presenting in 0.002% of the general population. Their etiology can be congenital or acquired. We present a review of recent literature related to their epidemiology, etiology, pathophysiology, clinical presentation, diagnostic approach, and therapeutic management.

Non-coronary cardiac findings and pitfalls in coronary computed tomography angiography

Non-coronary incidental findings are not rare. Kirsch et al found 67% non-coronary abnormalities with coronary computed tomography angiography (CCTA). Radiologists are expected to identify the extracoronary, intra- and para-cardiac anatomical structures and distinguish them from pathologic processes in CCTA. We have reviewed 2000 CCTA studies done at our institution with 64-MDCT. This pictorial essay presents case studies of non-atherosclerotic cardiovascular findings to recognize cardiac anatomic structures and how to distinguish them from pathologic processes. Correct interpretation of benign, clinically insignificant findings is crucial to avoid unnecessary additional imaging tests.

Echocardiography and 64-multislice computed tomography angiography in diagnosing coronary artery fistula

BACKGROUND/PURPOSES

There are various types of coronary artery fistula (CAF) with complex shapes; therefore, it is important to obtain a correct diagnosis and to understand its relations to the adjacent structures before surgery. This study evaluated echocardiography and 64-multislice computed tomography (64-MSCT) angiography in diagnosing CAF.

METHODS

Sixteen patients with CAF, confirmed by surgical operation or digital subtraction angiography, were examined by echocardiography. Five of them were further examined by 64-MSCT angiography for detailed anatomical information before surgery. The imaging data for echocardiography and 64-MSCT angiography were analyzed retrospectively.

RESULTS

Among the 16 patients, 12 were correctly diagnosed by echocardiography, of whom five were confirmed by 64-MSCT angiography. Four cases missed diagnosis by echocardiography, and one of these was correctly diagnosed by 64-MSCT. Seventeen fistulae were found, of which, two appeared in one patient. Ten fistulae originated from the left coronary artery and seven from the right. The draining site was the right heart in eight, pulmonary artery in five, left heart in three and aorta in one.

CONCLUSION

Echocardiography can act as the routine examination of CAF, and 64-MSCT angiography can provide more detailed anatomical and pathological information for surgery than echocardiography.

An S-shaped sinoatrial nodal artery coronary artery fistula demonstrated by multidetector CT

The presented case and discussion illustrate the use of CT coronary angiography to depict coronary artery fistulae. A 41-year-old man presented with an acute myocardial infarction. Invasive angiography revealed an incidental coronary artery fistula but was unable to depict its course. CT coronary angiography was undertaken to define the course and termination of the fistula. This confirmed a fistulous connection between the left circumflex artery and the superior vena cava that followed the typical course of an S-shaped sinoatrial nodal artery. Even in such an unusual anomaly this case highlights the ability of CT coronary angiography to accurately depict the coronary artery anatomy.

An overview of surgery options for congenital coronary artery anomalies

Congenital and acquired coronary artery anomalies are associated with significant morbidity and mortality and can be sudden in onset. The spectrum of congenital lesions include anomalous origin from the pulmonary artery, critical left main stenosis/atresia, coronary artery fistulas, anomalous aortic origin and intramyocardial courses. The spectrum of acquired lesions include Kawasaki disease, late postoperative obstructions in patients who had coronary artery surgical manipulations and iatrogenic injuries that can occur in the catheterization laboratory or the operating room. Surgical therapies for ischemic syndromes associated over the long term of these anomalies are presented herein.

Applying preoperative multidetector computed tomography to bilateral coronary artery fistulas

Coronary artery fistula arising from both the right coronary artery and the circumflex coronary artery is rare. A 28-year-old woman with non-insulin-dependent diabetes mellitus and end-stage renal disease who was on regular hemodialysis complained of recent progressive exertional dyspnea. Congestive heart failure was diagnosed during work-up for simultaneous kidney and pancreas transplantation. Bilateral coronary fistulas draining into the coronary sinus were found by coronary angiography and further characterized by multidetector computed tomography followed by 3D reconstruction preoperatively. The operation was performed smoothly without heart arrest.

Coronary artery-pulmonary vein fistula diagnosed by multidetector computed tomography

Coronary artery fistulas are rare congenital or acquired coronary artery anomalies that can originate from any of the three major coronary arteries and drain in all the cardiac chambers and great vessels. Multidetector computed tomography has provided cross-sectional anatomy of the heart with excellent spatial and temporal resolution, which shows the anatomical and functional changes in cardiac disorders. Here, the first case of noniatrogenic coronary artery to pulmonary vein fistula depicted by multidetector computed tomography has been presented.

Classic images: Cardiac computed tomography

Cardiac computed tomography (CT) has evolved into a valuable clinical tool for cardiac evaluation. Cardiac CT is increasingly used for imaging of the coronary arteries for the evaluation of (suspected) coronary artery disease, but many other cardiac structures may be the topic for CT investigation. This article reviews general indications for cardiac CT imaging. Common variants and pathologies of the cardiovascular system are illustrated by clinical examples.