Anomalies of cardiac venous drainage associated with abnormalities of cardiac conduction system

Persistent left superior vena cava isolation in patients with atrial fibrillation: Selective or empirical?

BACKGROUND

Persistent left superior vena cava (PLSVC) is the most prevalent form of thoracic venous abnormality and can serve as a significant arrhythmogenic source in atrial fibrillation (AF).

METHODS AND RESULTS

Among the 3950 patients who underwent radiofrequency ablation for AF between September 2014 to April 2020, 17 patients (mean age 59.4 ± 8.0 years, 64.7% male) with PLSVC were identified. Among them, nine patients (52.9%) had a prior history of pulmonary vein isolation (PVI) alone. Eight out of nine patients who experienced AF recurrence underwent PLSVC isolation with or without pulmonary vein (PV) reconnection. For the remaining eight patients (47.1%), PVI plus PLSVC isolation were performed during the index procedure. Ectopy originating from PLSVC was documented in 11 patients (64.7%) and successful PLSVC isolation was achieved in 16 patients (94.1%). After a median follow-up of 28.3 months, freedom from AF/ atrial tachycardia (AT) was observed in 13 patients (76.5%).

CONCLUSION

Empirical PLSVC isolation beyond PVI appears to be a feasible and safe strategy to prevent AF recurrence in patients with concomitant PLSVC.

Provocation and Localization of Arrhythmogenic Triggers from Persistent Left Superior Vena Cava in Patients with Atrial Fibrillation

BACKGROUND

Although pulmonary vein isolation (PVI) is an established procedure for atrial fibrillation (AF), non-PV foci play a crucial role in AF recurrence. Persistent left superior vena cava (PLSVC) has been reported as critical non-PV foci. However, the effectiveness of provocation of AF triggers from PLSVC remains unclear. This study was designed to validate the usefulness of provoking AF triggers from PLSVC.

METHODS

This multicenter retrospective study included 37 patients with AF and PLSVC. To provoke triggers, AF was cardioverted, and re-initiation of AF was monitored under high-dose isoproterenol infusion. The patients were divided into two groups: those whose PLSVC had arrhythmogenic triggers initiating AF (Group A) and those whose PLSVC did not have triggers (Group B). Group A underwent isolation of PLSVC after PVI. Group B received PVI only.

RESULTS

Group A had 14 patients, whereas Group B had 23 patients. After a 3-year follow-up, no difference in the success rate for maintaining sinus rhythm was observed between the two groups. Group A was significantly younger and had lower CHADS2-VASc scores than Group B.

CONCLUSIONS

The provocation of arrhythmogenic triggers from PLSVC was effective for the ablation strategy. PLSVC electrical isolation would not be necessary if arrhythmogenic triggers are not provoked.

Pacemaker Implantation in a Patient with Isolated Persistent Left Superior Vena Cava Draining into the Left Atrium: A Case Report and Brief Literature Review

Anomalies of the thoracic venous system are rare and usually discovered incidentally, but they become clinically relevant in the case of patients requiring cardiac device implantation. Persistent left superior vena cava is considered the most common venous drainage abnormality, with several anatomical variants that generate technical difficulties during pacemaker or defibrillator lead placement. We report a case of an isolated persistent left superior vena cava with abnormal drainage into the left atrium, associated with a hypoplastic right-sided superior vena cava, in a patient scheduled for permanent pacemaker implantation. Considering the patient's anatomical characteristics, a transvenous approach proved unfeasible and the procedure was successfully accomplished via the surgical placement of a left ventricle epicardial lead. We aim to emphasize the clinical importance of such venous anomalies and to discuss the practical implications and challenges derived from these types of conditions, especially in the field of electrophysiology.

Catheter ablation for atrial fibrillation in patients with persistent left superior vena cava: Case series and systematic review

Introduction

Persistent left superior vena cava (PLSVC) is the most common form of thoracic venous abnormality. Catheter ablation (CA) for atrial fibrillation (AF) can be complicated by the existence of PLSVC, which could act as an important arrhythmogenic mechanism in AF.

Methods and results

We reported a case series of patients with PLSVC who underwent CA for AF at our center between 2018 and 2021. A systematic search was also performed on PubMed, EMBASE, and Web of Science for research reporting CA for AF in patients with PLSVC. Sixteen patients with PLSVC were identified at our center. Ablation targeting PLSVC was performed in 5 patients in the index procedures and in four patients receiving redo procedures. One patient experienced acute procedure failure. After a median follow-up period of 15 months, only 6 (37.5%) patients remained free from AF/atrial tachycardia (AT) after a single procedure. In the systematic review, 11 studies with 167 patients were identified. Based on the included studies, the estimated prevalence of PLSVC in patients undergoing CA for AF was 0.7%. Ablation targeting PLSVC was performed in 121 (74.7%) patients. Major complications in patients with PLSVC receiving AF ablation procedure included four cases of cardiac tamponades (2%), three cases of cardiac effusion (1.5%), one case of ischemic stroke, and three cases of phrenic nerve injury (1.5%) (one left phrenic nerve and two right phrenic nerve). Pooled analysis revealed that after a median follow-up period of 15.6 months (IQR 12.0–74.0 months), the long-term AF/AT-free rate was 70.6% (95% CI 62.8–78.4%, I² = 0.0%) (Central illustration). Different ablation strategies for PLSVC were summarized and discussed in the systematic review.

Conclusion

In patients with PLSVC, recurrence of atrial arrhythmia after CA for AF is relatively common. Ablation aiming for PLSVC isolation is necessitated in most patients. The overall risk of procedural complications was within an acceptable range.

Persistent left superior vena cava as an incidental finding in the introduction of a transient pacemaker: A case report

The persistent left superior vena cava is the most common venous anomaly in the systemic drainage in adults and tends to be asymptomatic. The persistent left superior vena cava causes rhythm disorders such as tachyarrhythmias or bradyarrhythmias.We report a case of persistent left superior vena cava diagnosed in a 53-year-old female patient admitted due to an acute coronary syndrome associated with unstable bradycardia. A transvenous peacemaker impressed the left atrium; therefore, a transthoracic echocardiogram was required to diagnose persistent left superior vena cava. The patient needed management with percutaneous intervention; she had an adequate evolution and subsequent discharge from the intensive care unit.

Multimodality Imaging of Caval and Coronary Sinus Venous Anomalies

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Abnormal fetal development can produce several anomalies of the caval venous system.

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We present multimodality imaging of the most common caval venous anomalies.

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Each imaging modality provides incremental value when identifying these anomalies.

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Even normal variants may impact pacing lead or central venous catheter placement.

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Pathologic variants may lead to intracardiac shunting.

Classification and quantification of double superior vena cava evaluated by computed tomography imaging

BACKGROUND

A double superior vena cava (DSVC) may cause technical difficulties in some cardiovascular procedures. However, no quantitative data exist to describe the morphological features of this anomaly.

METHODS

From January 2015 to January 2019, the data of 128 consecutive patients diagnosed with DSVC on computed tomography (CT) images were retrospectively analyzed. We proposed an easy and rational method for DSVC classification based on the presence or absence of the left brachiocephalic vein (LBCV), the presence or absence of an anastomotic vein bridging the bilateral superior vena cava (SVC), and the drainage pattern of the left superior vena cava (LSVC). The following classifications were established: type I, LBVC absent, LSVC drainage into the right atrium via the coronary sinus; type II, LBCV present, LSVC drainage into the right atrium via the coronary sinus; type III, LBCV absent, LSVC drainage into the right atrium via the anastomosis; type IV, LBCV present, LSVC drainage into the right atrium via the anastomosis. The length, diameter, and area of the bilateral SVC and the coronary sinus were carefully measured across the 4 types.

RESULTS

Type I was the most frequently occurring type (66 of 128, 51.6%), followed by type II (43 of 128, 33.6%), then type III (15 of 128, 11.7%), and type IV (4 of 128, 3.1%). The LSVC was significantly longer than the right SVC (RSVC) in all 4 types, and the diameters of the LSVC were significantly larger in types without the LBCV (i.e., types I and III) (P<0.0001 for all). Additionally, the diameter of the coronary sinus in types I and II was triple that in types III and IV (P<0.0001), which was thought to be due to increased venous blood reflux through the coronary sinus.

CONCLUSIONS

The anatomical features of DSVC can be satisfactorily depicted on CT. The quantitative measurement of this anomaly by the reporting radiologists could assist clinicians to minimize the procedure-associated risks.

Permanent pacemaker implantation in a patient with persistent left superior vena cava with an absent right superior vena cava: A case report

Persistent left superior vena cava (PLSVC) is a common congenital anomaly of the thoracic venous system. PLSVC affects 0.3-0.5% of the general population, with 0.09-0.13% having PLSVC with an absent right superior vena cava. A 92-year-old woman was transported to our hospital by ambulance because of syncopal attacks lasting a few seconds. Electrocardiography showed paroxysmal supraventricular tachycardia and sinus arrest for up to 10 s with syncope when the arrhythmia stopped. This occurred repeatedly, and a diagnosis of sick sinus syndrome was made. The patient was scheduled for dual-chamber permanent pacemaker implantation. She had isolated PLSVC, and pacing lead was inserted into the right atrium through the PLSVC from her left subclavian vein. The "J" pre-shaped stylet was used to introduce the lead via the tricuspid valve to the right ventricular outflow tract (RVOT) and placed in the septum of RVOT. Another lead was advanced into the right atrial appendage using the "J" pre-shaped stylet. After three years of implantation, fluoroscopy showed a stable position of pacing leads, and pacemaker interrogations showed no major changes in parameters. <Learning objective: Persistent left superior vena cava (PLSVC) is a common anomaly of the thoracic venous system. PLSVC is either isolated or associated with an absent right superior vena cava and a connection with the left atrium creating a shunt. In isolated PLSVC and PLSVC with an absent right superior vena cava, implantation of a permanent pacemaker is difficult but possible using conventional devices.>.

Persistence of Left Superior Vena Cava in Nonagenarian Undergoing Pacemaker Implant: Case Report

Introduction: The persistence of the left superior vena cava (PLSVC) is a congenital malformation of the veins that drain blood from the upper body, causing the flow to the right atrium to be processed through the coronary sinus. Case report: We describe the case of a nonagenarian woman, previously asymptomatic until she developed total atrioventricular block when she was referred for implantation of a double chamber pacemaker. Persistence of the left superior vena cava was detected during the procedure and confirmed by venography. The implantation of the electrodes was performed safely and without complications. Conclusion: Despite not usually causing symptoms, the presence of PLSVC can make invasive procedures a challenging task. Knowledge of anatomy and the use of simple techniques can facilitate interventions in this scenario.

Persistent Left Superior Vena Cava with Absent Right Superior Vena Cava and Discrete Subaortic Stenosis Diagnosed in a Patient with Sick Sinus Syndrome: A Case Report and Brief Review of the Literature

A persistent left superior vena cava (PLSVC) is the most frequent anomaly of the venous drainage system. While both a right and left superior vena cava (SVC) are usually present, a unique, left-sided SVC, also known as an isolated PLSVC, accounts for only 10–20% of cases. It is frequently associated with arrhythmias and other congenital cardiac anomalies. Though it is usually an asymptomatic condition, it may pose significant problems whenever central venous access is needed. We report a case of an isolated PLSVC that was diagnosed incidentally during pacemaker implantation for sinus node dysfunction. The venous anomaly was associated with subvalvular aortic stenosis determined by a subaortic membrane; this particular association of congenital cardiovascular anomalies is a rare finding, with only a few cases reported in the literature. We aim to highlight the clinical and practical implications of this condition, as well as to discuss the embryonic development and diagnostic methods of this congenital defect.

Autopsy findings of an isolated persistent left superior vena cava in an intrauterine dead fetus

Persistent left superior vena cava (PLSVC) is one of the cardiac system abnormalities with a 0.3-0.5% incidence and caused by inadequate obliteration of the left anterior cardinal vein during embryonic development. Prognosis of PLSVC is generally assumed to be good if it is not accompanied by other cardiac system abnormalities. During the routine ultrasound control of a patient at 25th week of pregnancy at the Obstetrics and Gynecology Department of Mersin University, PLSVC anomaly was detected in an intrauterine fetus. Then, intrauterine death occurred and after removal of the deceased fetus, PLSVC diagnosis was confirmed by autopsy. According to the autopsy findings, right superior vena cava (SVC) and azygos vein were found in normal course. PLSVC opened into the right atrium via enlarged coronary sinus. There was no connection between the two SVCs. On the left side of posterior mediastinum, instead of hemiazygos or accessory hemiazygos veins, a vein symmetrical to azygos was opened into PLSVC, similar to the one on the right. No other cardiac anomaly associated with PLSVC or any other pathology in the other parts of body that could be responsible for death was discovered during autopsy. There was no evidence indicating that PLSVC played any role in intrauterine exitus of the present case. However, as mentioned in the literature, the ectopic beats in the atrium wall of patients with isolated PLSVC and enlarged coronary sinus may lead to pathologies in the conduction system of the heart. Considering the intrauterine death of an isolated PLSVC case associated with cardiac conduction pathologies, we recommend that the common assumption of 'isolated PLSVC is not associated with death' should be reviewed by studies on large series and even intrauterine cases should be closely monitored for cardiac arrhythmia.

Impact of persistent left superior vena cava on radiofrequency catheter ablation in patients with atrial fibrillation

AIMS

The impact of persistent left superior vena cava (PLSVC) in atrial fibrillation (AF) patients undergoing radiofrequency catheter ablation (RFCA) is not well known. We performed this analysis to evaluate the electrophysiological characteristics of PLSVC and its role in triggering and maintaining AF.

METHODS AND RESULTS

Patients with AF referred to two tertiary hospitals were screened and patients with PLSVC in pre-RFCA imaging studies were enrolled. Among 3967 patients, PLSVC was present in 36 patients (0.9%). There were four morphological types of PLSVC: type 1, atresia of the right superior vena cava (SVC) (n = 2); type 2A, dual SVCs with an anastomosis between right and left SVCs (n = 15); type 2B, dual SVCs without an anastomosis (n = 16); type 3, PLSVC draining into the left atrium (LA; n = 2); and unclassified in one patient. Thirty-two patients underwent RFCA and electrophysiology study focusing on PLSVC: PLSVC was the trigger of AF in 48.4% of patients and the driver of AF in 46.9% of patients. Cumulatively, PLSVC was a trigger or driver of AF in 22 patients (68.8%). Whether to ablate PLSVC was determined by the results of electrophysiology study, and no significant difference in the late recurrence rate was observed between patients who did and did not have either trigger or driver from PLSVC.

CONCLUSION

Pre-RFCA cardiac imaging revealed PLSVC in 0.9% of AF patients. This study demonstrated that PLSVC has an important role in initiating and maintaining AF in substantial proportion of patients. Electrophysiology study focusing on PLSVC can help to decide whether to ablate PLSVC.

Cryoballoon ablation for paroxysmal atrial fibrillation in a case of persistent left superior vena cava

Background

Atrial fibrillation (AF) usually originates from pulmonary veins (PVs) but can also be caused by pulmonary veins outside, such as the coronary sinus (CS), the superior vena cava (SVC), and the ligament of Marshall.

Case presentation

A 69-year-old male with a history of palpitations for 10 years was referred to our institute because of its recurrence for half a day. A dynamic electrocardiogram revealed sinus rhythm (SR) and paroxysmal AF. Echocardiography demonstrated normal cardiac structure, and physical examination results were unremarkable. However, computed tomography angiography (CTA) showed a persistent left superior vena cava (LSVC) but no indication of thrombosis in the left atria. A cryoablation catheter was inserted into the PV. After the PV was successfully isolated, AF was still observed. After cardioversion was synchronized, SR was detected, but AF occurred again in less than a minute. Finally, we observed ectopic atrial electrical activity originating from the LSVC and successfully ablated it.

Conclusions

An LSVC may be a substrate for initiating or perpetuating atrial arrhythmia. Cryoballoon ablation can help treat AF originating from the LSVC.

A Case of Multiple Cardiovascular and Tracheal Anomalies Presented with Wolff-Parkinson-White Syndrome in a Middle-aged Adult

Congenital cardiovascular anomalies, such as dextrocardia, persistent left superior vena cava (SVC), and pulmonary artery (PA) sling, are rare disorders. These congenital anomalies can occur alone, or coincide with other congenital malformations. In the majority of cases, congenital anomalies are detected early in life by certain signs and symptoms. A 56-year-old man with no previous medical history was admitted due to recurrent wide QRS complex tachycardia with hemodynamic collapse. A chest radiograph showed dextrocardia. After synchronized cardioversion, an electrocardiogram revealed Wolff-Parkinson-White (WPW) syndrome. Persistent left SVC, PA sling, and right tracheal bronchus were also detected by a chest computed tomography (CT) scan. He was diagnosed with paroxysmal supraventricular tachycardia (PSVT) associated with WPW syndrome, and underwent radiofrequency ablation. We reported the first case of situs solitus dextrocardia coexisting with persistent left SVC, PA sling and right tracheal bronchus presented with WPW and PSVT in a middle-aged adult. In patients with a cardiovascular anomaly, clinicians should consider thorough evaluation of possibly combined cardiovascular and airway malformations and cardiac dysrhythmia.

Isolated persistent left superior vena cava: A case report and its clinical implications

The venous anomaly of a persistent left superior vena cava (PLSVC) affects 0.3%-0.5% of the general population. PLSVC with absent right superior vena cava, also termed as "isolated PLSVC," is an extremely rare venous anomaly. Almost half of the patients with isolated PLSVC have cardiac anomalies in the form of atrial septal defect, endocardial cushion defects, or tetralogy of Fallot. Isolated PLSVC is usually innocuous. Its discovery, however, has important clinical implications. It can pose clinical difficulties with central venous access, cardiothoracic surgeries, and pacemaker implantation. When it drains to the left atrium, it may create a right to left shunt. In this case report, we present the incidental finding of isolated PLSVC in a patient who underwent aortic valve replacement. Awareness about this condition and its variations is important to avoid complications.

The incidental finding of a persistent left superior vena cava: implications for primary care providers-case and review

Persistent left superior vena cava (PLSVC) is the most common thoracic venous anomaly and is a persistent congenital remnant of the vena caval system from early cardiac development. Patients with congenital anomalous venous return are at increased risk of developing various cardiac arrhythmias, due to derangement of embryologic conductive tissue during the early development of the heart. Previously this discovery was commonly made during the placement of pacemakers or defibrillators for the treatment of the arrhythmias, when the operator encountered difficulty with proper lead deployment. However, in today's world of various easily obtainable imaging modalities, PLSVC is being discovered more and more by primary care providers during routine testing or screening for other ailments. Given the known association between anomalous venous return and the propensity for cardiac arrhythmias, we review the embryology of PLSVC and the mechanisms by which it leads to conduction abnormalities. We also provide the practitioner with recommendations for certain baseline cardiac observations and suggestions for proper surveillance in hopes that better understanding will reduce unnecessary and potentially harmful testing, premature subspecialty referral, and unneeded patient anxiety.

Left-sided superior vena cava and venous hyperoxia masquerading as inadvertent carotid artery catheterization

BACKGROUND

A persistent left-sided superior vena cava (PLSVC) is a rare, often asymptomatic, venous anomaly that may be first diagnosed during central venous catheterization. During chest radiograph interpretation, a PLSVC can be confused with inadvertent arterial catheterization.

CASE REPORT

We describe the presentation of a 45-year-old man with end-stage liver disease who required central venous catheterization for treatment of septic shock. An aberrantly placed catheter noted on chest radiograph and an elevated central venous oxygen saturation gave the appearance of inadvertent carotid artery catheterization. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: A persistent left-sided superior vena cava can masquerade as an inadvertent cannulation of the carotid artery during central line placement. It is important for emergency physicians to be aware of this possibility when evaluating a chest radiograph with an aberrantly placed catheter. Venous hyperoxia may further complicate attempts to differentiate between arterial and venous catheterization in patients with septic shock. After confirmatory tests, the emergency physician should consider removal of the catheter due to potential complications.

A novel method of placing right ventricular leads in patients with persistent left superior vena cava using a conventional j stylet

BACKGROUND

Locating pacemaker electrodes can become complicated by congenital abnormalities such as persistent left superior vena cava (LSVC).

OBJECTIVE

To evaluate a technique for the implanting of ventricular electrode in patients with persistent LSVC.

MATERIALS AND METHODS

The study was carried out from June 2001 to June 2010 involving all patients who were admitted to the Hospital Universitario Mayor, Instituto de Corazon de Bogota and Hospital Universitario Clinica San Rafael (Bogota-Colombia) for implanting pacemakers or cardiac defibrillators. LSVC was diagnosed by fluoroscopic observation (anterior-posterior view) of the course of the stylet. Four steps were followed: 1) Move the electrode with a straight stylet to the right atrium. 2) Change the straight stylet by a conventional J stylet and push the electrode to the lateral or anterolateral wall of the right atrium. 3) Remove the guide 3-5 cm and 4) Push the electrode which crosses the tricuspid valve into the right ventricle and finally deploy the active fixation mechanism.

RESULTS

A total of 1198 patients were admitted for pacemaker or cardiac defibrillator implant during the 9-year study period, 1114 received a left subclavian venous approach. There were 573 males and 541 females. Persistent LSVC was found in five patients (0.45%) Fluoroscopy time for implanting the ventricular electrode ranged from 60 to 250 seconds, 40 to 92 minutes being taken to complete the whole procedure.

CONCLUSION

We present a simple and rapid technique for electrode placement in patients with LSVC using usual J guide and active fixation electrodes with high success.

Prevalence of persistent superior vena cava and association with congenital heart anomalies

A contralateral persistent superior vena cava (PSVC) can occur in a normal child or in association with congenital heart defects (CHDs). Its prevalence has been demonstrated in relatively small cohorts. We aim to assess the frequency of a PSVC in a large cohort of children with and without CHDs. To estimate its significance, we have searched for a PSVC in all children referred for echocardiography in our institution during a 16.5-year period. A group of 17,219 children comprised 8,140 children with a structural heart anomaly and 9,079 children with a structurally normal heart. Association between a PSVC and specific classes of CHD were looked for. A total of 288 children (1.7%) had a PSVC; 0.56% (51 of 9,079) in the normal heart group and 2.9% (237 of 8,140) in the congenital heart anomalies group. Odds ratio for having heart anomaly in the presence of PSVC was 5.2 (95% confidence interval 3.7 to 7.0). A PSVC was above all associated with atrioventricular septal defects, conotruncal malformations, and left-sided defects. The odds ratio of having PSVC in the aforementioned malformations compared with the normal heart group was 23.8, 13.6, and 11.0, respectively. In conclusion, although present in normal subjects, PSVC was more often associated with congenital heart and other anomalies, especially with atrioventricular septal defects, conotruncal malformations, and left-sided defects.

High prevalence rate of left superior vena cava determined by echocardiography in patients with congenital heart disease in Saudi Arabia

BACKGROUND

Persistent left superior vena cava (LSVC) is one of the common anomalies of the systemic veins. Its prevalence is 0.1-0.3% in the general population and is more common with congenital heart disease (CHD). The importance of detecting persistent LSVC prior to cardiac surgery is paramount for systemic veins cannulations.

AIM

The aim was to evaluate the prevalence of persistent LSVC in patients with CHD in Saudi Arabia.

METHODS

All patients referred to our institution had echocardiography. All complete studies were reviewed for the presence of persistent LSVC. A computerized database was created including the demographic data, CHD diagnoses, and the presence of persistent LSVC.

RESULTS

A total of 2,042 were examined with an age range of 1 day to 16 years. The complete echocardiographic studies were 1,832 (90%) of whom 738 (40%) patients had CHD. The prevalence of persistent LSVC in patients with CHD was 7.8% (OR 9.26, 95% CI 4.7-18.2, p<0.001). The most common cardiac defect associated with persistent LSVC was complete atrioventricular septal defect (AVSD); all patients with AVSD had Down syndrome. The total number of patients with AVSD was 41, and persistent LSVC was found in 11 (26%) of them (odds ratio 5.1, 95% CI 2.4-10.8, p<0.001).

CONCLUSIONS

The prevalence of persistent LSVC in the current population is almost double the reported prevalence obtained using the same echocardiographic screening tool.

Isolated persistent left-sided superior vena cava, giant coronary sinus, atrial tachycardia and heart failure in a child

Persistence of a left-sided superior vena cava (PLSVC) with absent right superior vena cava (isolated PLSVC) is a very rare venous malformation and commonly associated with congenital heart disease or alterations of the cardiac situs. We describe an unusual case of a young boy presenting with persistent atrial tachycardia and congestive heart failure. He was detected to have unexplained grossly dilated right atrium, right ventricle with systolic dysfunction and a giant coronary sinus (CS). The dilated CS closely mimicked a pseudo cor-triatriatum on echocardiography. Contrast echocardiography from both arms revealed opacification of the CS before the right atrium. Bilateral upper limb venography confirmed the presence of absent right SVC and isolated persistent left SVC draining into the giant coronary sinus.

Mitral valve repair in patient with absent right superior vena cava in visceroatrial situs solitus

We report on a 74-year-old woman with an absence of right superior vena cava in visceroatrial situs solitus who underwent mitral valve plasty for severe mitral regurgitation. Preoperative three-dimensional computed tomography revealed an absent right and persistent left superior vena cava that drained into the right atrium by way of the coronary sinus. Perioperaively, placement of pulmonary artery catheter, site of venous cannulation, and management of associated rhythm abnormalities were great concern. Obtaining the information about this central venous malformation preoperatively, we performed mitral valve plasty without any difficulties related to this anomaly.

Systemic venous anatomy in congenital heart disease: implications for electrophysiologic testing and catheter ablation

INTRODUCTION

Cardiac arrhythmias are a significant problem in patients with congenital heart disease. Many patients with congenital heart disease have abnormal systemic venous anatomy which can complicate electrophysiologic testing, catheter ablation and pacemaker and defibrillator implantation. We reviewed the systemic venous anatomy in a cohort of patients undergoing electrophysiologic testing and catheter ablation.

METHODS AND RESULTS

We reviewed all electrophysiologic studies performed in patients with adult congenital heart disease (n = 80) at our institution between January 1998 and October 2009. Ten patients (13%) had a congenital systemic venous anomaly. Of these, seven (9%) had a left superior vena cava and four (5%) had infrahepatic interruption of the inferior vena cava (two had both anomalies). One patient's inferior vena cava was connected to a left-sided atrium; she had right atrial isomerism. In four patients (40%), systemic venous abnormalities were discovered at the time of electrophysiologic testing.

CONCLUSIONS

Systemic venous anomalies occur frequently in the congenital heart disease population and may complicate electrophysiologic testing and catheter ablation. Pre-procedural imaging may assist in facilitating a successful procedure.

Recognition of persistent left superior vena cava in non-congenital patients undergoing cardiac surgery

Persistent left superior vena cava (PLSVC) represents the most frequent congenital malformation of the thoracic venous drainage system. In adults referred to surgery for an acquired cardiac disease, abnormal venous drainage may be missed if not carefully researched. Discovering a previously undiagnosed PLSVC during cardiopulmonary bypass (CPB) may present some inconvenience for both the perfusionist and the surgeon, especially during a minimally invasive approach. The authors believe PLSVC probably may represent an under-reported condition. A careful screening of patients undergoing cardiac surgery may prove helpful. In particular, a complete echocardiographic study may help to better diagnose this condition before surgery. Different signs may raise the suspicion of PLSVC and should be carefully researched during preoperative patient work-up.

CT appearance of persistent left superior vena cava, anomalous right superior pulmonary venous return into the right-sided superior vena cava and a sinus venosus-type atrial septal defect

We present findings of persistent left superior vena cava, anomalous right superior pulmonary venous return into the right-sided superior vena cava and a sinus venosus-type atrial septal defect detected incidentally by CT pulmonary angiography. To our knowledge, there has been no previous case report with all of the above findings detected by CT. In addition to the radiological findings and their clinical significance, the anatomy and embryological explanation of each anomaly is discussed.

An interesting case: bilateral superior vena cava in a patient with end stage renal disease

A left superior vena cava, which is present in 0.5% of the population, is the result of persistence of the embryonic left anterior cardinal vein and is usually considered a normal variant. We present our experience of an incidental discovery of bilateral superior vena cava during routine evaluation of suspected intra-fistula stenosis in a dialysis-dependent patient with end stage renal disease. Our images were consistent with a left-sided venous structure draining into the heart with an independent right side superior vena cava as evidenced by fluoroscopy. There was also evidence of a 60% intra-fistula stenosis. To conclude, twin superior vena cava may be present as draining vessels independent of each other or as part of a duplicate caval drainage. While cases of persistent left superior vena cava have been associated with disturbances of cardiac impulse formation and conduction no such significant associations have been found in patients with bilateral superior vena cava. However, the variant anatomy may confound efforts during central venous catheterization as well as alter flow characteristics, such that one could postulate that the anatomy may also affect the maturation of an arteriovenous fistula.

CT appearances of congential and acquired abnormalities of the superior vena cava

A wide spectrum of congenital and acquired abnormalities can affect the superior vena cava (SVC). Congenital anomalies can present either as incidental findings or be associated with underlying cardiac abnormalities; these include left-sided or double SVCs and anomalous venous drainages. Acquired conditions involving the SVC, including SVC obstruction syndrome, can be secondary to extrinsic compression or intrinsic occlusion. The CT appearances, the incidence, and associations of these conditions are discussed.

Congenitally persistent left superior vena cava: a possible unpleasant problem during invasive procedures

The persistence of the left superior vena cava is the most common thoracic vein anomaly, but, nevertheless, it continues to be an unpleasant finding during invasive diagnostic cardiovascular procedures and is sometimes a challenge during invasive therapeutic interventions. Persistent left superior vena cava usually occurs in 0.5% of the normal population and 0.47% of patients undergoing pacemaker or implantable cardioverter defibrillator implantation. The incidence in congenital heart disease varies (2-5%), and it is more frequent in stenosis or pulmonary atresia, D-transposition, complete atrioventricular septal defects, and anomalous pulmonary vein drainage. The diagnosis is almost always incidental, during anaesthesiological procedures such as central vein placement, or diagnostic cardiovascular procedures, such as right heart catheterization, but it may sometimes be discovered during therapeutic paediatric cardiac catheterization, such as during patent foramen ovale or atrial septal defect transcatheter closure. Echocardiography is useful to identify patients in whom computed tomography and especially magnetic resonance imaging may pose a definitive diagnosis. In indicated cases, when cyanosis is present and the anomaly is isolated, treatment options include surgical ligation and transcatheter closure using large occluder devices, whereas more challenging surgical repairs are needed when the anomaly is associated with other complex congenital heart diseases. Different specialists at different levels such as anaesthesiologists, invasive cardiologists, electrophysiologists and cardiac surgeons should be aware of the variety of technical problems that may be caused by a persistent LSVC.

Left superior vena cava in pediatric cardiology associated with extra-cardiac anomalies

BACKGROUND

In case reports and small series, the coexistence of a persistent left superior vena cava (LSVC) and extra-cardiac anomalies has been noted. However, an association between LSVC and extra-cardiac anomalies has not been documented. We investigated the association between LSVC and extra-cardiac anomalies in patients referred to our tertiary pediatric cardiology department between 1998 and 2005.

METHODS

Trans-thoracic echocardiograms were performed on 4426 consecutive patients. Cardiac and extra-cardiac anomalies were registered prospectively in a computerized database. In a retrospective observational design, characteristics of patients with LSVC were collected.

RESULTS

In 4426 patients, 1825 (41%) were diagnosed with congenital heart disease (CHD) and 295 patients (7%) with extra-cardiac anomalies. LSVC was present in 102 patients, of which 89 (87%) with CHD (OR 10.2, 95% CI 5.7 to 18.3, p<0.001) and 61 (60%) with extra-cardiac anomalies (OR 26.0, 95% CI 17.1 to 39.5, p<0.001). Confirmed syndromes were present in 43 LSVC patients (42%), including VACTERL association (vertebral defects, anal atresia, cardiac malformations, tracheo-esophageal fistula with esophageal atresia, radial and renal dysplasia, and limb anomalies, 9%), trisomy 21 (7%), 22q11 (6%) and CHARGE association (coloboma, heart defects, atresia of choanae, retardation, genital and ear anomalies, 5%). In 17 LSVC patients (17%) with multiple anomalies in different organ systems, a syndrome diagnosis was not confirmed.

CONCLUSIONS

The LSVC appears to be indicative for both cardiac and extra-cardiac anomalies (e.g. septal defects, tetralogy of Fallot, VACTERL and CHARGE association). Disorders in the development of the secondary heart field may be causal to this combination of anomalies.

Atrial fibrillation originating from persistent left superior vena cava

BACKGROUND

The left superior vena cava (LSVC) is the embryological precursor of the ligament of Marshall, which has been implicated in the initiation and maintenance of atrial fibrillation (AF). Rarely, the LSVC may persist and has been associated with some organized arrhythmias, though not with AF. We report 5 patients in whom the LSVC was a source of ectopy, initiating AF.

METHODS AND RESULTS

In 5 patients (4 men; age, 46+/-11 years) with symptomatic drug-refractory AF, ectopy from the LSVC resulting in AF was observed after pulmonary vein isolation. The ectopics were spontaneous in 2 and induced by isoproterenol in the others and preceded P-wave onset by 67+/-13 ms. During multielectrode or electroanatomic mapping, venous potentials were recorded circumferentially at the proximal LSVC near its junction with the coronary sinus (CS), but at the mid-LSVC level, they were recorded only on part of the circumference. The LSVC was electrically connected to the lateral left atrium (LA) and through the CS to the right atrium, with 4.1+/-2.3 CS-LSVC and 1.6+/-0.5 LA-LSVC connections per patient. Catheter ablation in the LSVC targeting these connections resulted in electrical isolation in 4 of the 5 patients without complications. After 15+/-10 months, the 4 patients with successful isolation, including 1 who had successful reablation for LA flutter, remained in sinus rhythm without drugs.

CONCLUSIONS

The LSVC can be the arrhythmogenic source of AF with connections to the CS and LA. Ablation of these connections resulted in electrical isolation.

Accessory pathway associated with an anomalous coronary sinus

Congenital coronary sinus anomalies are unusual and they rarely coexist with accessory atrioventricular pathways. These anomalies are generally asymptomatic, however they can cause difficulty in mapping. The association between accessory pathway and coronary sinus anomalies may suggest an embryologic link. In this case, we report a male patient with permanent form of reciprocating tachycardia coexistent with anomalous coronary sinus.