Coronary Artery Development: Origin, Malformations, and Translational Vascular Reparative Therapy

Coronary Artery Anomalies: A Computed Tomography Angiography Pictorial Review

Coronary arteries have a wide range of anatomical variability, and their spectrum ranges from asymptomatic cases to those predisposed to hemodynamic compromise or even sudden cardiac death. This paper aims to review the classification of coronary artery anomalies (CAAs) and illustrate their imaging characteristics by highlighting the important role of CT coronary angiography. Some of the coronary anomalies usually met in current practice are the high origin coronary artery, multiple ostia, aberrant origin from the opposite/non-coronary Valsalva sinus, single coronary artery, ALCAPA syndrome, duplications of the left anterior descending artery, coronary fistulas, and extracardiac terminations. CT coronary angiography is a non-invasive diagnostic modality for CAAs. The complex anatomy of these anomalies can be accurately described by employing 3D reconstructions and post-processing techniques. Knowledge of the imaging characteristics and potential functional impact of these anomalies is essential for accurate diagnosis and therapeutic planning of patients.

Anomalous origin of the left circumflex artery from the pulmonary artery associated with non-compaction of the left ventricle: usefulness of multimodality imaging-a case report

Background

The anomalous origin of the left circumflex artery from the pulmonary artery (ACXAPA) is a very rare coronary anomaly. Only a few cases have been reported until today, from incidental findings to autopsy reports after sudden cardiac death.

Case summary

We report here for the first time the case of a man, previously monitored for asymptomatic left ventricular non-compaction cardiomyopathy, who presented with non-ST myocardial infarction and was diagnosed with ACXAPA. Complementary tests confirmed ischaemia in the corresponding territory, and the patient was referred to surgery for reimplantation of the circumflex artery.

Discussion

Left ventricular non-compaction cardiomyopathy is a rare congenital cardiomyopathy whose association with coronary anomalies, not with ACXAPA, had previously been described until now. A related embryological origin could potentially explain this association. The management of a coronary anomaly should indicate dedicated multimodality cardiac imaging in order to not disregard the association with underlying cardiomyopathy.

Primary percutaneous coronary intervention on split left coronary artery: Two case reports

The split left coronary artery (LCA) is an anomaly of coronary arteries connection related to the aorta, presenting more often in patients who underwent invasive coronary angiography compared to coronary computed tomography angiography. Although this anomaly causes no hemodynamic impairment, failure to recognize may lead to incorrect diagnosis and prolonged procedures during acute myocardial infarction resulting in serious complications. We report 2 cases of split left coronary artery presenting with acute myocardial infarction who underwent primary percutaneous coronary interventions (pPCI) with excellent outcomes. In the both cases, electrocardiogram demonstrated ST-segment elevation and cardiac biomarkers were increased. Also, before coronary angiography in both patients echocardiographic examination was performed revealing hypokinesis who corresponded with the territory of occluded coronary arteries. During invasive further coronary examinations split left artery was found, besides the culprit lesion in the left anterior descending artery (LAD). Successful percutaneous stenting was performed on LAD achieving TIMI flow grade 3 in both cases. Prompt recognition of split LCA in the setting of acute myocardial infarction during pPCI, it is essential to achieve appropriate treatment and avoid potential clinical consequences.

Two genetic variants in NEXN and ABCC6 genes found in a patient with right coronary artery to right ventricle fistula combined with giant coronary aneurysm and patent ductus arteriosus

Objective

Coronary artery fistula, defined as communication between a coronary artery and a great vessel or a cardiac chamber, is a relatively rare anomaly with an estimated incidence of 0.002% in the general population. It could be combined with a giant coronary artery aneurysm, with an incidence of 5.9% of the total incidence rate of CAF in the general population. The pathogenesis of these two combined anomalies is not clear, and we aimed to detect whether genetic abnormalities underlie the pathogenesis of these rarely combined anomalies.

Materials and methods

A 6-year-old patient with a diagnosis of the right coronary artery to right ventricle fistula combined with a giant right coronary artery aneurysm and patent ductus arteriosus underwent a surgical repair at our center. The diagnosis was confirmed by echocardiography, CT, and surgery. DNA was extracted from the peripheral venous blood samples of the patient and his mother after informed consent was obtained. Hematoxylin and Eosin (HE) and Alizarin red staining were performed on the excised coronary artery aneurysm. Exome sequencing and in silico analyses were performed to detect detrimental genetic variants.

Results

No obvious abnormalities were found in the excised coronary artery aneurysm. A heterozygous truncated variant (NM_144573: c.G298T; p.G100X) in the NEXN gene and a missense variant (NM_001171: c.G1312A; p.V438M) in the ABCC6 gene were carried by the patient but not by his mother.

Conclusion

The NEXN-truncated variant, NEXN-G100X, is associated with the development of coronary arteries and congenital coronary artery anomalies.

Revascularization of chronic total occlusion coronary artery and cardiac regeneration

Coronary chronic total occlusion (CTO) contributes to the progression of heart failure in patients with ischemic cardiomyopathy. Randomized controlled trials demonstrated that percutaneous coronary intervention (PCI) for CTO significantly improves angina symptoms and quality of life but fails to reduce clinical events compared with optimal medical therapy. Even so, intervening physicians strongly support CTO-PCI. Cardiac regeneration therapy after CTO-PCI should be a promising approach to improving the prognosis of ischemic cardiomyopathy. However, the relationship between CTO revascularization and cardiac regeneration has rarely been studied, and experimental studies on cardiac regeneration usually employ rodent models with permanent ligation of the coronary artery rather than reopening of the occlusive artery. Limited early-stage clinical trials demonstrated that cell therapy for cardiac regeneration in ischemic cardiomyopathy reduces scar size, reverses cardiac remodeling, and promotes angiogenesis. This review focuses on the status quo of CTO-PCI in ischemic cardiomyopathy and the clinical prospect of cardiac regeneration in this setting.

Total anomalous origin of the coronary arteries from the pulmonary artery: a systematic review

BACKGROUND

Although rare, coronary artery anomalies can have significant clinical implications. Total anomalous origin of the coronary arteries from the pulmonary artery (TCAPA) represents a rare subtype of coronary artery anomaly for which little is known. The aim of this review was to characterise the presentation, utilised diagnostic modalities, associated cardiac lesions, and treatment strategies in patients with TCAPA.

METHODS

A systematic review was performed for cases of TCAPA using PubMed, Embase, and Web of Science. Keywords searched included "total anomalous origin of the coronary arteries from the pulmonary artery," "single ostium anomalous coronary artery from the pulmonary artery," and "anomalous origin of both coronary arteries from the pulmonary artery."

RESULTS

Fifty-seven cases of TCAPA were identified in 50 manuscripts. Fifty-eight per cent of patients were male and the median age at presentation was 10 days (mean 1.71 ± 6.6 years, range 0 days-39 years). Most patients were symptomatic at the time of presentation; cyanosis (n = 22) and respiratory distress (n = 14) were the most common symptoms. Cases were most commonly diagnosed at autopsy (n = 26, 45.6%), but operative intervention was pursued in 22 cases (45.6%); aortic re-implantation (n = 14) and a Takeuchi-type repair (n = 7) were the most common routes of repair.

CONCLUSIONS

The clinical presentation of patients with TCAPA was found to be variable, likely related to the presence of associated cardiac lesions. TCAPA should be considered in patients with suspected anomalous origin of the left coronary artery from the pulmonary artery for the serious consequences that can occur if not promptly corrected.

Anomalous Origin of the Circumflex or Left Anterior Descending Artery From the Pulmonary Artery

Anomalous origin of the circumflex or left anterior descending artery from the pulmonary artery (ACxAPA and ALADAPA, respectively) are rare congenital coronary anomalies with clinical presentation varying from an asymptomatic murmur to sudden cardiac arrest. A systematic review was performed, and 46 cases of ACxAPA and 51 cases of ALADAPA were identified in 87 articles. Data were collected and analyzed from each case. A better understanding of ACxAPA/ALADAPA can provide information to providers who encounter this lesion as well as provide insight into coronary artery development which may help in the understanding of coronary artery anomalies.

Proepicardium: Current Understanding of its Structure, Induction, and Fate

The proepicardium (PE) is a transitory extracardiac embryonic structure which plays a crucial role in cardiac morphogenesis and delivers various cell lineages to the developing heart. The PE arises from the lateral plate mesoderm (LPM) and is present in all vertebrate species. During development, mesothelial cells of the PE reach the naked myocardium either as free-floating aggregates in the form of vesicles or via a tissue bridge; subsequently, they attach to the myocardium and, finally, form the third layer of a mature heart-the epicardium. After undergoing epithelial-to-mesenchymal transition (EMT) some of the epicardial cells migrate into the myocardial wall and differentiate into fibroblasts, smooth muscle cells, and possibly other cell types. Despite many recent findings, the molecular pathways that control not only proepicardial induction and differentiation but also epicardial formation and epicardial cell fate are poorly understood. Knowledge about these events is essential because molecular mechanisms that occur during embryonic development have been shown to be reactivated in pathological conditions, for example, after myocardial infarction, during hypertensive heart disease or other cardiovascular diseases. Therefore, in this review we intended to summarize the current knowledge about PE formation and structure, as well as proepicardial cell fate in animals commonly used as models for studies on heart development. Anat Rec, 302:893-903, 2019. © 2018 Wiley Periodicals, Inc.