Coronary artery fistula as another cause of acute heart failure
Danay Pérez Mijenes, Mariana Lobo, João Caiano Gil, Joana Alves Vaz
Internal Medicine Department, Hospital Pedro Hispano, Unidade Local de Saúde de Matosinhos, Senhora da Hora, Portugal
Doi: 10.12890/2023_004053 - European Journal of Case Reports in Internal Medicine - © EFIM 2023
Received: 07/08/2023
Accepted: 24/08/2023
Published: 06/09/2023

How to cite this article: Pérez Mijenes D, Lobo M, Gil JC, Vaz JA. Coronary artery fistula as another cause of acute heart failure. EJCRIM 2023;10:doi:10.12890/2023_004053.

Conflicts of Interests: The authors declare there are no competing interests.
Patient Consent: The patient consented and gave permission to publish their clinical history.
This article is licensed under a Commons Attribution Non-Commercial 4.0 License

ABSTRACT

Coronary artery fistulas (CAFs) are rare defects in the coronary circulation system that are usually diagnosed incidentally with cardiac imaging. Although the prognosis of coronary artery fistulas is highly variable, the complications to which they predispose patients are ultimately the determining factor. The authors describe a case of a 56-year-old male, a smoker, hospitalised for worsening dyspnoea on progressively smaller efforts, in the context of acute heart failure. During hospitalisation and imaging exams, a coronary-bronchial fistula was identified.

LEARNING POINTS

KEYWORDS

Coronary artery fistula; coronary steal phenomenon; coronary to pulmonary artery fistula

INTRODUCTION

The impact of a CAF on heart function can vary depending on the size and location of the abnormal connection. If the fistula is small and does not cause significant shunting of blood away from the coronary circulation, it may not produce any noticeable symptoms or health issues. However, larger and more significant coronary artery fistulas can potentially lead to heart failure[1,3], as we describe below.

CASE DESCRIPTION

A 56-year-old man with significant smoking habits (44 pack years), dyslipidaemia, obesity and moderate alcohol consumption was admitted to the emergency service with exertional dyspnoea and angina. On admission he was polypnoeic and tachycardic, with intercostal retraction and oxygen desaturation – SpO2 88%. Pulmonary auscultation showed inspiratory crackles and sparse wheezing. Cardiac auscultation revealed two standard rhythmic sounds without murmurs. Electrocardiogram showed sinus rhythm 74/min, and inversion of T-wave in DII, DIII, aVF and V4 to V6. Blood tests revealed no elevation of myocardial necrosis markers but an elevation of natriuretic peptide (NT-proBNP 2913 pg/ml). Transthoracic echocardiography showed dilated cardiomyopathy with severe depression of left ventricular systolic function (25% Simpson’s ejection fraction) and marked global hypocontractility. A diagnostic cardiac catheterisation was proposed to clarify the ischaemic aetiology, which revealed severe coronary disease in two vessels: the anterior descending artery with a 90% lesion in the proximal segment, and the nondominant right coronary artery with an 80% lesion in the right ventricular branch. The same examination identified a large-calibre branch originating from the middle segment of the circumflex artery supplying the mediastinal structure. Because of these findings, a complementary study was performed with pulmonary computed tomography angiography and computed tomography coronarography, which showed an anomalous vessel originating from the circumflex artery (after the emergence of the first obtuse marginal branch), initially descending and later ascending, crossing the left pulmonary veins anteriorly. This vessel crosses the midline anteriorly of the right main bronchus (at this point it reaches a maximum calibre of 4 mm) and moves towards the right pulmonary hilum, irrigating the right bronchial tree, with findings suggestive of bronchiectasis without the presence of a mediastinal mass (Fig. 1,2). Given the potential consequences of coronary steal and the high risk of haemorrhage to the lung with severe haemoptysis if antiplatelet agents were used to treat his ischaemic disease, the patient was discussed in a multidisciplinary meeting (Internal Medicine, Cardiology, Cardiac Surgery and Radiology). Surgical intervention was proposed after confirmation of viability in the coronary territory of the descending anterior artery. Antiplatelet therapy was started and there was no evidence of pulmonary haemorrhage or other complications. The patient underwent surgery without intercurrences and was discharged on the seventh day.

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Figure 1. Abnormal vessel crossing the midline of the right main bronchus

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Figure 2. Vessel pathway to the right pulmonary hilum

DISCUSSION

Coronary artery fistulas are rare congenital or acquired defects in the coronary circulation that affect 0.1% to 0.2% of the population[1,3,5]. They are characterised by a connection between one or more coronary arteries and a cardiac chamber or a large vessel of the systemic or pulmonary circulation. Most coronary artery fistulae originate from the right coronary artery (40–60%) and mainly connect to the right atrium, right ventricle or pulmonary trunk[3]. Although it is a rare congenital or acquired entity, a CAF may present with different signs and symptoms depending on the number, size, location, haemodynamic profile and underlying comorbidities of the patient[1,3,4]. Clinical sequelae of CAFs may include dilatation of the heart chamber and dyspnoea, as well as ischaemia symptoms. Atrial fibrillation is perhaps the most common arrhythmia, although almost any arrhythmia can occur, especially when the atria and ventricles begin to dilate[5]. Multimodality imaging is essential for diagnosis and therapeutic decision-making. Coronary angiography and coronary computed tomography angiography (CTA) are considered highly reliable in the diagnosis of coronary artery fistulae. Reported outcomes from limited case series on transcatheter CAF closure demonstrate that this procedure is effective in most patients with suitable anatomy; however, it is not free of risks. The updated 2018 American College of Cardiology/American Heart Association guidelines recommend transcatheter closure or surgical closure for giant fistulas or when symptoms indicate obvious heart failure[4,5]. In our patient, given the coronary anatomy and large-calibre fistula, surgical intervention was suggested. However, the need for individual therapeutic decisions for each patient type should be made and discussed by a multidisciplinary team in centres with experience in both methods. This case highlights a rare entity that is usually detected during coronary angiography but, if symptomatic, may become relevant because of possible coronary steal syndrome.

References
  1. Torres C, Gjergjindreaj M, Torres-Ortiz H, Fuentes J, Beohar N. Coronary steal syndrome secondary to large coronary to pulmonary artery fistulas. Cureus 2022;14:e30267.
  2. Rao SS, Agasthi P. Coronary artery fistula. StatPearls. 2023. Treasure Island (FL): StatPearls Publishing; Jan. 2023.
  3. Al-Hijji M, El Sabbagh A, El Hajj S, AlKhouli M, El Sabawi B, Cabalka A et al. Coronary artery fistulas: indications, techniques, outcomes, and complications of transcatheter fistula closure. ACC Cardiovasc Interv 2021;14:1393–1406.
  4. Sandor B, Bogats G, Toth L, Habon T. Surgical treatment of heart failure due to giant coronary artery fistula: a case report. ESC Heart Fail 2020;7:3203–3207.
  5. Oster M, Bhatt AB, Zaragoza-Macias E, Dendukuri N, Marelli A. Interventional therapy versus medical therapy for secundum atrial septal defect: a systematic review (part 2) for the 2018 AHA/ACC guideline for the management of adults with congenital heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol 2019;73:1579–1595.