Coronary Fistula Between Left Anterior Descending Artery (LAD) and Pulmonary Artery (PA) Leading to Sudden Cardiac Death: Case Report with Literature Review

Coronary artery fistula following surgical myectomy for hypertrophic obstructive cardiomyopathy: a case report

Background

Coronary artery fistula is a rare, but recognized complication of surgical myectomy. Although most communicate with the right heart, a large fistula into the left ventricular cavity may result in a shunt haemodynamically analogous to aortic regurgitation. Understanding the variable presentation of iatrogenic coronary fistulae and the optimal evaluation strategy is critical to obtaining a timely diagnosis and instituting treatment.

Case summary

We report the case of a 57-year-old renal transplant recipient admitted for evaluation of presyncope, one-year post-surgical myectomy for hypertrophic obstructive cardiomyopathy. An iatrogenic coronary artery fistula was suspected by transthoracic echocardiography, and later confirmed with both non-invasive and invasive coronary angiography.

Discussion

We highlight various cardiac imaging modalities that confirmed the diagnosis of coronary artery fistula and helped to determine the clinical significance. We report the tailored approach often required to determine the anatomic and haemodynamic characteristics of coronary fistulae and outline potential management strategies.

RNA binding proteins in cardiovascular development and disease

Congenital heart disease (CHD) is the most common birth defect affecting>1.35 million newborn babies worldwide. CHD can lead to prenatal, neonatal, postnatal lethality or life-long cardiac complications. RNA binding protein (RBP) mutations or variants are emerging as contributors to CHDs. RBPs are wizards of gene regulation and are major contributors to mRNA and protein landscape. However, not much is known about RBPs in the developing heart and their contributions to CHD. In this chapter, we will discuss our current knowledge about specific RBPs implicated in CHDs. We are in an exciting era to study RBPs using the currently available and highly successful RNA-based therapies and methodologies. Understanding how RBPs shape the developing heart will unveil their contributions to CHD. Identifying their target RNAs in the embryonic heart will ultimately lead to RNA-based treatments for congenital heart disease.

Minimally invasive coil embolization for significant left-to-right shunts due to giant coronary-to-pulmonary artery fistulas: a case report

Background

Coronary-to-pulmonary artery fistula (CPF) is a rare disease, and its optimal treatment strategy remains controversial. Herein, we report a rare case of minimally invasive coil embolization of giant CPFs.

Case summary

A 78-year-old man with a history of persistent atrial fibrillation and lumbar canal stenosis presented to our hospital with breathlessness. Cardiac computed tomography revealed giant CPFs inducing a significant left-to-right shunt (Qp/Qs 1/2.1) with a coronary artery aneurysm smaller than the size indicated for surgical treatment. To reduce the left-to-right shunt flow, coil embolization procedures for the fistulas were performed twice. Initially, the fistula arising from the right coronary artery was embolized using three Target® XXL (6 × 40 mm, 5 × 20 mm) and two Target® XL SOFT (4 × 12 mm) coils (Stryker Inc., Tokyo, Japan). One month later, the fistulas arising separately from the left coronary artery were embolized. After the procedures, the major shunt flow disappeared angiographically, and Qp/Qs significantly decreased to 1/1.2. Additionally, the fractional flow reserve of the left coronary artery increased from 0.79 to 0.93, and cardiopulmonary exercise testing showed an improvement in his exercise tolerance.

Discussion

In similar cases, a surgical procedure with ligation of the CPFs combined with resection of a small aneurysm and coronary artery bypass grafting would normally have been considered the best approach. However, endovascular treatment targeting only the fistulas was a superior strategy considering the patient's age. The coil embolization technique effectively controlled the shunt flow of the CPFs. This technique is considerably less invasive than surgical therapy.

Reversible Pulmonary Hypertension due to Combined Fistula between the Left Anterior Descending Artery (LAD) and Pulmonary Artery and Severe Stenosis of the LAD

Coronary artery fistulas are usually diagnosed accidentally without the presence of any symptoms. On the other hand, the combination of fistula between the left anterior descending artery (LAD) and pulmonary artery (PA) and severe stenosis of the LAD, as in this case report, is a potential life-threatening condition. A 72-year-old patient was treated surgically after being diagnosed with fistula between the LAD and PA, severe stenosis of the LAD, and severe pulmonary hypertension. In following paragraphs, the case of this man and significant issues regarding the development and management of coronary artery fistulas are analyzed.

Images in cardiovascular medicine voluminous left main stem to pulmonary artery fistula: A conservative approach

The presence of a coronary arteriovenous fistula is almost rare in the adult population, even rare when associated with aortic valve insufficiency. Management and treatment options can vary and depend on a single patient. In our case, a large fistula with a rounded origin started from the roof of the left main stem, just attached to the wall of the aortic root, and finished with a very narrowed end in the pulmonary trunk. Due to its anatomical position and to the potential complications related to a proximal surgical closure as well as the incidental discovery in adult age (without signs or symptoms until the operation), we decided to have a conservative approach, leaving untouched the fistula. No intraoperative, perioperative, and follow-up signs of myocardial ischemia were observed.