Electrophysiological features and radiofrequency catheter ablation of supraventricular tachycardia in patients with persistent left superior vena cava

High-density electro-anatomical activation mapping to guide slow pathway modification in patients with persistent left superior vena cava

BACKGROUND

Slow pathway (SP) mapping and modification can be challenging in patients with persistent left superior vena cava (PLSVC) due to anatomical variance of Koch's triangle (KT) and coronary sinus (CS) dilatation. There is a lack of studies using detailed 3-dimensional (3D) electro-anatomical mapping (EAM) to investigate conduction characteristics and guide ablation targets in this condition.

OBJECTIVES

To describe a novel technique of slow pathway mapping and ablation in sinus rhythm using 3D EAM in patients with PLSVC after validation in a cohort with normal coronary sinus anatomy.

METHODS

Seven patients with PLSVC and dual AV node physiology who underwent slow pathway modification with the use of 3D EAM were included. Twenty-one normal heart patients with AV nodal re-entrant tachycardias formed the validation group. High-resolution, ultra-high-density local activation timing (LAT) mapping of the right atrial septum and proximal coronary sinus in sinus rhythm was performed.

RESULTS

SP ablation targets were consistently identified by an area in the right atrial septum with the latest activation time and multi-component atrial electrogram (EGM) adjacent to a region with isochronal crowding (deceleration zone). In PLSVC patients, these targets were located at or within 1 cm of the mid anterior CS ostium. Ablation in this area led to successful SP modification reaching standard clinical endpoints with a median of 43 sec of radio frequency energy or 14 mins of cryoablation without complications.

CONCLUSION

High-resolution activation mapping of Koch's triangle in sinus rhythm can facilitate localisation and safe slow pathway ablation in patients with PLSVC.

Retrograde fast pathway cryoablation inside the coronary sinus for slow-fast atrioventricular nodal reentrant tachycardia in a patient with persistent left superior vena cava

INTRODUCTION

Persistent left superior vena cava (PLSVC) is accompanied by enlarged coronary sinus (CS) and deformation of the triangle of Koch. This makes anatomical evaluation of the atrioventricular (AV) nodal pathways difficult.

METHODS

We attempted cryoablation of retrograde fast pathway located in the enlarged CS roof of PLSVC for slow-fast AV nodal reentrant tachycardia (AVNRT) induced by inadvertent antegrade fast pathway elimination during ablation of left atrial tachycardia.

RESULTS

Slow-fast AVNRT was successfully eliminated without AV block progression.

CONCLUSIONS

This is the first case of successful retrograde fast pathway ablation of the CS ostial roof for slow-fast AVNRT with PLSVC.

Cryoballoon Ablation Beyond Pulmonary Vein Isolation in the Setting of Persistent Atrial Fibrillation

INTRODUCTION

Catheter ablation has been demonstrated to be a safe and an effective treatment for drug resistant atrial fibrillation (AF); electrical isolation of pulmonary veins (PVI) is the main strategy in paroxysmal AF, since pulmonary vein triggers have a pivotal role in its pathogenesis; non-paroxysmal AF is a complex arrhythmia that results from the interplay of a substrate, namely AF-induced electrical and structural atrial remodeling, and a trigger that can be often found outside pulmonary veins, namely non-pulmonary veins triggers.

AREAS COVERED

The aim of this review is to provide a state-of-the-art overview of non-pulmonary veins triggers with special focus on cryoballoon (CB) catheter ablation.

EXPERT OPINION

Besides PVI, CB catheter ablation of non-pulmonary veins triggers is a novel and promising strategy for non-paroxysmal AF.

Anatomy for ablation of atrioventricular nodal reentry tachycardia and accessory pathways

The atrioventricular (AV) valve plane and the central septum are of particular importance for electrophysiological diagnosis and interventional therapy of supraventricular tachycardias because accessory electrical connections of various types may be present in addition to the specific conduction system. Although modern 3D electroanatomic reconstruction systems including high-density mapping can be of great assistance, detailed knowledge of the anatomic structures involved, their complex three-dimensional arrangement, and their electrical properties in conjunction with electrophysiological features of supraventricular arrhythmias is essential for safe and efficient electrophysiological treatment. The aim of this article is to present current anatomical, topographical, and electrophysiological findings against the background of historical, seminal, and still indispensable literature.

Pediatric Left Posteroseptal Accessory Pathway Ablation from Giant Coronary Sinus with Persistent Left Superior Cava

We report a pediatric patient with persistent left superior vena cava and a D-transposition of great arteries, which is an uncommon relation. It is crucial to know the anatomy of the persistent left superior vena cava and the dilated coronary sinus to plan the mapping techniques in cases of posterior accessory pathways.

Cryoablation for atrioventricular nodal re-entrant tachycardia associated with persistent left superior vena cava

Catheter ablation for atrioventricular nodal re-entrant tachycardia (AVNRT) in patients with persistent left superior vena cava (PLSVC) is challenging because of anatomical abnormalities of Koch's triangle associated with the enlarged coronary sinus ostium. We present the Case of successful ablation in a patient with PLSVC using the cryoablation technique. The ablation was successfully performed without damaging the conduction system by virtue of “cryomapping” and “cryoadhesion.” Cryoablation is a safe and efficacious alternative to radiofrequency catheter ablation for the treatment of AVNRT associated with PLSVC.

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Catheter ablation for AVNRT in patients with PLSVC is challenging

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We performed successful ablation in a PLSVC patient with the cryoablation technique

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Ablation was successfully performed without damaging the conduction system

Supraventricular tachycardia in patients with coronary sinus stenosis/atresia: Prevalence, anatomical features, and ablation outcomes

BACKGROUND

Supraventricular tachycardia (SVT) with coronary sinus (CS) ostial atresia (CSA) or coronary sinus stenosis (CSS) causes difficulty in electrophysiological procedures, but its characteristics are poorly understood.

OBJECTIVE

Study the anatomical and clinical features of SVT patients with CSA/CSS.

METHODS

Of 6128 patients with SVT undergoing electrophysiological procedures, consecutive patients with CSA/CSS were enrolled, and the baseline characteristics, imaging materials, intraoperative data, and follow-up outcomes were analyzed.

RESULTS

Thirteen patients, seven with CSA and six with CSS, underwent the electrophysiological procedure. Decapolar catheters were placed into the proximal CS in three cases, while the rest were placed at the free wall of the right atrium. Fourteen arrhythmias were confirmed: four atrioventricular nodal reentrant tachycardias, five left-sided accessory pathways, three paroxysmal atrial fibrillations, and two atrial flutters (AFLs). In addition to three patients who underwent only an electrophysiological study, the acute ablation success rate was 100% in 10 cases, with no procedure-related complications. After a median follow-up period of 59.6 months, only one case of atypical AFL recurred. For those cases (seven CSA and two CSS) with a total of 10 anomalous types of CS drainage, three types were classified: from the CS to the persistent left superior vena cava (n = 3), from an unroofed CS (n = 3), and from the CS to the small cardiac vein (n = 3) or Thebesian vein (n = 1).

CONCLUSION

Patients with CSA/CSS may develop different kinds of SVT. Electrophysiological procedures for such patients are feasible and effective. An individualized mapping strategy based on the three types of CS drainage will be helpful.

Radiofrequency catheter ablation in a patient with dextrocardia, persistent left superior vena cava, and atrioventricular nodal reentrant tachycardia: A case report

RATIONALE

Dextrocardia is a rare congenital heart disease, while the persistent left superior vena cava (PLSVC) is an uncommon congenital vascular malformation. It is extremely rare for a person to have dextrocardia and PLSVC. A case with a combination of dextrocardia, PLSVC, and atrioventricular nodal reentrant tachycardia has not been reported.

PATIENT CONCERNS

A 51-year-old woman was admitted to the hospital with palpitations. The physical examination revealed a heart rate of patient increased significantly, and that apex beating was found in the right fifth intercostal space approximately 0.5 cm from the midclavicular line.

DIAGNOSIS

We used different techniques, including electrocardiography, esophagus heart electrophysiology, chest radiograph, and cardiac color Doppler echocardiography to reveal the presence of the combination of dextrocardia, PLSVC, and supraventricular tachycardia.

INTERVENTIONS

We terminated tachycardia by esophageal pacing and cured patients with radiofrequency catheter ablation (RFCA).

OUTCOMES

The complex structural anomalies presented great technical challenges for interventional treatments. After consulting the literature, thorough examination and understanding of the structural anatomy and anomalies of the vena cava and cardiac chambers, we successfully treated this patient by RFCA. After half a year of follow-up, the patient did not have palpitations, and no arrhythmia was seen on the electrocardiography.

LESSONS

Physicians need to be aware that the key to the success of RFCA, in this case, is to clarify the complexity of the morphological and anatomical structures of dextrocardia accompanying PLSVC and to consult and understand the experience of access vessels reported in relevant cases before the operation.

Ablation of atrioventricular-nodal-reentrant- tachycardia in a patient with left-sided superior vena cava and dilated coronary sinus

Atrioventricular (AV)-nodal-reentrant-tachycardia is a rare association in a patient with persistent left-sided superior vena cava and dilated coronary sinus. There are a few inherent difficulties in ablation in this condition, viz., difficulty in localization of good site for ablation and difficulty in stabilization of the ablation catheter at the designated site, making it difficult to produce transmural lesions and increasing risk of producing AV block. We hereby present a case highlighting the difficulties and possible solutions for them.

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.

Radiofrequency catheter ablation of accessory pathways at the site of prior valve surgery

BACKGROUND

Radiofrequency catheter ablation (RFCA) for accessory pathways (APs) at the site of prior valve surgery (VS) remains challenging. We aimed to clarify the factors associated with successful RFCA for such APs.

METHODS

Upon reviewing a RFCA registry and previous case reports, we included nine patients who underwent RFCA of APs at the site of prior VS (total-VS group; age, 34.0 [24.5-45.0] years; men, 4/9) and 196 patients who underwent RFCA of APs with no history of VS (no-VS group; age, 40.5 [23.0-54.0] years; men, 114/196). Electrophysiological features, procedural details, and outcomes were examined.

RESULTS

Accessory pathway exhibited decremental conduction in four of nine patients in the total-VS group. The number of RFCA attempts was significantly higher in the total-VS group than in the no-VS group (10.0 [4.5-14.5] vs 2.0 [1.0-3.0]; P < 0.001). In four patients who underwent mitral VS, successful RFCA was achieved using the transaortic approach, coronary sinus (CS) approach, or bipolar ablation. In three patients who underwent tricuspid VS, successful RFCA was achieved using the above-prosthetics or trans-prosthetics approach. In two patients, RFCA failed. The trans-prosthetics approach and bipolar ablation technique were effective. The transaortic and CS approaches were occasionally effective. The transseptal approach was ineffective.

CONCLUSIONS

Successful RFCA of APs at the site of prior VS can be achieved by detailed mapping of the areas both above and below the prosthetic valve, as well as by ensuring effective radiofrequency energy delivery using various catheter approaches and RFCA techniques.