Congenital Thoracic Venous Anomalies in Adults: Morphologic MR Imaging

Association of Prenatally Diagnosed Isolated Single Left Superior Vena Cava and Postnatal Development of Coarctation of the Aorta

To report the prevalence of coarctation of the aorta (CoA) in fetuses with single left superior vena cava (SL-SVC) and to evaluate changes in echocardiographic measurements. Additionally, to report the prevalence of associated malformations. Retrospective observational study of fetuses diagnosed with SL-SVC between 2012 and 2021 at a tertiary fetal cardiology unit. In fetuses without intracardiac abnormalities, Z-scores of the ventricles, great arteries, and Doppler flow patterns are reported. We identified 47 fetuses with SL-SVC of which 8/47 (17%) had abnormal intracardiac anatomy. One fetus was lost to follow-up. Of those with normal intracardiac anatomy and postnatal follow-up (38), karyotype abnormalities were confirmed in 2/38 (5%) and ECA in 8/38 (21%). 33/38 were live-born. None developed CoA postnatally. Paired analysis of Z-scores between early and late scans of 24 fetuses showed that diameters of the right heart structures and Doppler flows of tricuspid valve increased significantly during pregnancy, while the left heart structures and flow patterns did not change. The median risk of CoA did not change between the early and the late scan. We did not observe CoA in this cohort. A degree of ventricular asymmetry was present, but this was due to right heart dominance rather than hypoplasia of left heart structures. This likely reflects redistribution of blood and does not appear to confer increased risk of CoA. Predictive models of the postnatal development of CoA which set the dimensions of right and left heart structures in relation might not be applicable in this situation.

Thoracic Vascular Variants and Anomalies: Imaging Findings, Review of the Embryology, and Clinical Features

Thoracic vascular malformations are a set of complex congenital abnormalities that result in major alterations of the patient's anatomy. It can be discovered incidentally or the anomalies may generate heart failure with a right-to-left shunt, dysphagia, dyspnea, stridor, cough, recurrent bronchopulmonary infections, hypoxemia, paradoxical emboli, and occasionally apneas and massive hemothorax.

The knowledge of the embryology, and the normal development of the vascular structures of the thorax, allows to understand these abnormalities—and thus helps in making an accurate diagnosis—with its possible complications, symptoms, and treatments for the patient. The following is a review of the most common thoracic vascular malformations and their imaging findings.

Cardiac Implantable Electronic Devices in Different Anatomical Types of Persistent Left Superior Vena Cava: Case Series and Brief Review of the Literature

Persistent left superior vena cava (PLSVC) is the most common congenital malformation of the thoracic venous system, being present in 0.3% to 0.5% of the general population. In the majority of the cases, PLSVC is asymptomatic, but in certain patients, it can manifest through several symptoms, such as arrhythmias and cyanosis, especially when it is associated with complex cardiac pathologies. The clinical significance of this venous anomaly depends on the anatomical variant of the drainage site. In this article, we will present the experience of our clinic, with patients with PLSVC that were diagnosed intraprocedurally, during cardiac pacemaker (CP) or cardioverter defibrillator (ICD) implantation, highlighting the technical difficulties that this anomaly poses for cardiac device implantation. Out of 4000 patients who were admitted to our clinic for CP or ICD implantation, we encountered six cases of PLSVC (four reported in this article and two previously published) corresponding to different anatomical types of this congenital anomaly. In all of these situations, we had to adapt our technique to the patient's anatomy in order to avoid certain complications, the most serious being the improper placement of the right ventricle lead at the level of the coronary sinus.

Persistent left superior vena cava: An anatomical variation

The persistent left superior vena cava (LSVC) is a common anomaly of congenital heart disease. The presence of LSVC is commonly associated with other congenital cardiac anomalies such as atrial septal defect, tetralogy of fallot, aortic coarctation, ventricular septal defect and very rarely it occurs as an isolated finding. During a routine dissection for undergraduate students, a persistent LSVC along with variation in anterior cardiac vein and right septal pouch (RSP) was observed in heart of an approximately 48-year-old male cadaver. The persistent LSVC was draining into the right atrium via coronary sinus. The persistent LSVC is usually insignificant haemodynamically as commonly it drains into right atrium via coronary sinus, but incidental finding of LSVC is important to surgeons, interventional nephrologists and radiologists before placement of central venous access device. The insertion of central venous catheter via left internal jugular vein is difficult in presence of persistent LSVC. The right superior vena cava was normal. An anterior cardiac vein joined with the right marginal vein to form a common vein. The common vein opened into the right atrium. We also observed a RSP attached to the limbus fossa ovalis inferiorly which is a kangaroo pouch-like structure. A septal pouch is potential site predispose to thrombus formation and is more common on left side. In this case report we discuss embryology, clinical significance and review of literature related to persistent LSVC, anterior cardiac vein and SP.

Permanent pacemaker implantation in a challenging anatomy: Persistent left superior vena cava

The persistence of the left superior vena cava is one of the most common abnormalities that could affect the thoracic venous return, despite its rare occurrence. It can usually be found as the only or in combination with other congenital cardiac abnormalities. Even though it is usually asymptomatic and it rarely has important consequences on the hemodynamics, it could sometimes represent a serious threat. In this regard, PLSVC often represents an incidental finding during an invasive procedure or imaging. We present an interesting case of a 66-year-old patient, with permanent atrial fibrillation and chronic kidney disease who presented to our clinic for a syncope due to complete atrioventricular block. The implant procedure was marked by the incidental intraprocedural finding of unusual venous anatomy. This anomaly included the absence of the superior vena cava, with the communication of the right brachiocephalic trunk and right subclavian vein with a persistent left superior vena cava which drainage directly into the coronary sinus. The right-side approach, as well as the limitation of using contrast-based venography, due to the kidney disease, made the procedure more difficult, but the final position of an active fixation ventricular lead was successfully achieved with optimal and stable pacing parameters through the formation of a particular curve of the lead stylet. Persistence of the left superior vena cava is a venous anomaly, which is frequently suspicioned at transthoracic echocardiography examination when the examiner found a dilated coronary sinus but diagnosed on the implant table of a cardiac device. These anomalies can pose problems and exponentially increase the procedural time even in experienced hands.

Case Report of a Left-sided Superior Vena Cava Causing Unique Positioning of Central Line

Introduction

Persistent left-sided superior vena cava is a rare congenital venous malformation. While often clinically asymptomatic, these variations in normal anatomy may give rise to complications with central venous catheter placement.

Case Report

We present a case of a 71-year-old male who presented to the emergency department with sepsis of unknown etiology. A right-sided central venous catheter was placed, and due to a persistent left-sided superior vena cava the post-procedure chest radiograph showed a uniquely positioned catheter tip within the left atrium.

Conclusion

A persistent left-sided superior vena cava may lead to uniquely positioned catheter tip placement on post-procedural imaging. This case demonstrates the need to consider variants in normal venous anatomy, such as persistent left-sided superior vena cava, to aid with correct interpretation of post-procedure imaging findings.

Persistent left superior vena cava

Persistent left superior vena cava (PLSVC) is the most common congenital malformation of thoracic venous return and is present in 0.3 to 0.5% of individuals in the general population. This heart specimen was dissected from a 35-year-old male cadaver whose cause of death was determined as non-cardiac. The heart was examined and we found a PLSVC draining into the coronary sinus. The right superior vena cava was present with a small-diameter ostium. An anomalous pulmonary vein pattern was observed; there was a common trunk to the left superior and left inferior pulmonary veins (diameter 17.8 mm) and an additional middle right pulmonary vein (diameter 2.7 mm) with two classic right pulmonary veins. The PLSVC draining into the coronary sinus had led to its enlargement, which could have altered the cardiac haemodynamics by significantly reducing the size of the left atrium and impeding its outflow via the mitral valve.