Giant coronary artery fistula complicated with coronary artery aneurysm and acute myocardial infarction: a case report

Growing Coronary Aneurysm Secondary to Coronary Fistula Despite Decreased Pulmonary Blood Flow/Systemic Blood Flow Ratio in a Child: A Case Report

Coronary aneurysm secondary to coronary fistula is a rare condition, with no existing report on its pathological examination. We report the case of a patient diagnosed with a right coronary artery fistula with coronary aneurysm during the fetal period. During follow-up after delivery, the aneurysm became larger, even though the shunt size decreased. We were afraid the aneurysm would rupture and therefore, planned elective catheter embolization. At the age of 4 years, the patient underwent surgery, which involved closing the fistula and making the lumen of the aneurysm smaller. However, the surgery was not catheter embolization as planned because segment 3 branched off from the largest aneurysm where we planned to embolize. Pathologically, the structure of the coronary artery differed from that of a healthy one, with thickened intima and media, fewer scattered smooth muscle cells, widely distributed elastic fibers, and mucoid degeneration in the media. The structure of the coronary artery suggested that the vessel wall was weak and that the aneurysm would rupture if not treated. Postoperative coronary angiography showed that segment 2 was obstructed, while the collaterals from the left coronary artery perfused the area. We could have treated the fistula with a catheter as scheduled.

A rare case of dual congenital coronary cameral fistula and myocardial bridge: A case report

RATIONALE

A coronary artery fistula (CAF) is an anomalous communication between a coronary artery and a cardiac chamber or great vessel. It is a rare congenital anomaly that is often small and asymptomatic, occurring in only 0.002% of the general population. Most CAFs originate from the right coronary artery and flow into the right cardiac system. Although extremely rare, some cases may originate from the bilateral coronary arteries and flow into the left ventricle.

PATIENT CONCERNS

Herein, we report a rare case of a 55-year-old male smoker with no history of heart disease or cardiac surgery, who presented with a 5-year history of recurrent chest congestion, palpitations, and shortness of breath. On physical examination, his heart and lungs revealed normal findings without cardiac murmurs and no systemic or pulmonary edema. Moreover, 24-hour ambulatory electrocardiography showed no signs of ischemia but exhibited a short array of ventricular tachycardia and short atrial tachycardia. Chest computed tomography showed left apical emphysema without cardiomegaly and pulmonary congestion. Furthermore, coronary angiography revealed dual congenital coronary cameral fistula, a complex CAF with a left circumflex artery-left ventricle fistula and a right coronary artery-left ventricle fistula, complicated with a myocardial bridge.

DIAGNOSIS AND INTERVENTIONS

A diagnosis of left circumflex artery-left ventricle fistula complicated with a right coronary artery-left ventricle fistula and myocardial bridge was made. Since the patient refused surgery, medical management with enteric-coated aspirin, sustained-release metoprolol, and atorvastatin calcium was initiated.

OUTCOMES AND LESSON

Currently, the patient is now asymptomatic and in good condition since 6 months after undergoing conservative treatment with β-blockers.

RRM2 Improves Cardiomyocyte Proliferation after Myocardial Ischemia Reperfusion Injury through the Hippo-YAP Pathway

Objective

Ribonucleotide reductase M2 (RRM2) as an enzyme that catalyzes the deoxyreduction of nucleosides to deoxyribonucleoside triphosphate (dNTP) has been extensively studied, and it plays a crucial role in regulating cell proliferation. However, its role in ischemia-reperfusion injury (I/RI) is still unclear.

Methods

SD rats were used as the research object to detect the expression of RRM2 in the myocardium by constructing an I/RI model. At the same time, primary SD neonatal rat cardiomyocytes were extracted, and hypoxia/reoxygenation (H/R) treatment simulated the I/RI model. Using transfection technology to overexpress RRM2 in cardiomyocytes, quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) was used to detect the expression of RRM2, Cell Counting Kit-8 (CCK-8) assay was used to detect cell viability, and immunofluorescence staining was used to detect Ki67 and EdU-positive cells. Western blot (WB) technology was used to detect YAP and its phosphorylation expression.

Results

qRT-PCR results indicated that the expression of RRM2 was inhibited in the model group, and cardiomyocytes overexpressing RRM2 can obviously promote the proliferation of primary cardiomyocytes and improve the damage of cardiac structure and function caused by I/R. At the same time, RRM2 can promote the increase of YAP protein expression and the increase of Cyclin D1 mRNA expression.

Conclusion

RRM2 expression was downregulated in myocardial tissue with I/R. After overexpression of RRM2, cardiomyocyte proliferation was upregulated and the Hippo-YAP signaling pathway was activated.

Left circumflex artery pericardia fistula combined with huge pseudoaneurysm: a rare case report

Background

Coronary artery fistula refers to an abnormal communication between a coronary artery and great vessel, a cardiac chamber or other structure. The left circumflex artery (LCX) pericardia fistula combined with huge pseudoaneurysm is extremely rare.

Case presentation

A 39-year-old young female was admitted into our hospital because of palpitation and shortness of breath. Coronary computed tomography angiography (CCTA) showed a huge pseudoaneurysm located in pericardium. Coronary angiography revealed the LCX pericardia fistula. Then surgical treatment was performed. She was in good condition without complications after surgery.

Conclusions

Coronary artery fistula combined with pseudoaneurysm can be caused by congenital factors. Early surgical treatment can relieve the patient's symptoms and prevent the occurrence of adverse cardiovascular events.

Coronary Artery Fistulas: A Review of the Current and Future Roles of Imaging

Coronary artery fistulas are uncommon but clinically important entities that may produce symptoms and significant complications such as angina, myocardial infarction, coronary artery aneurysm formation, and congestive heart failure. Multiple fistula types have been recognized, and classification uses factors such as etiology, coronary artery origin, and drainage site. Both invasive and noninvasive imaging play an important role in the management and treatment of these patients, and often times, more than one modality is necessary for comprehensive evaluation of coronary fistulas. Recent advances in both functional and anatomic imaging will likely also play a growing role in fistula evaluation. The purpose of this article is to review the classification, pathophysiology, clinical presentations, imaging findings, treatment, and future imaging directions of coronary artery fistulas.