Development of an atrial transseptal puncture procedure in horses to access the left heart: An ultrasound-guided jugular vein and transhepatic approach

BACKGROUND

Radiofrequency ablation has been successfully applied to treat right atrial arrhythmias in horses. Ablation of left-sided arrhythmias requires a retrograde transarterial approach which is complicated. In human medicine, the left atrium is accessed through transseptal puncture (TSP) of the fossa ovalis (FO) using a caudal approach via the femoral vein.

OBJECTIVES

To develop a zero fluoroscopy TSP technique for horses using a jugular vein (cranial) and transhepatic (caudal) approach.

STUDY DESIGN

In vivo experimental study.

METHODS

Transseptal puncture was performed in 18 horses admitted for euthanasia and donated for scientific research under general anaesthesia: using a jugular vein approach (10 horses), a transhepatic approach (2 horses) or both (6 horses). Radiofrequency energy was applied on a guidewire to perforate the FO and allow sheath advancement under intracardiac and transthoracic echocardiographic guidance. Puncture lesions were inspected post-mortem.

RESULTS

Transseptal puncture was successful in 17/18 horses, of which 15/16 jugular vein approaches and 5/8 transhepatic approaches. Failure was due to technical malfunction, inability to advance the guidewire toward the heart and inability to advance the sheath through the FO. Intracardiac echocardiography was essential to safely guide the puncture process. Atrial arrhythmias caused by the TSP occurred in 13/18 horses. Puncture lesions were found in the right atrium in the FO region, and left atrium ventral to pulmonary vein ostium III.

MAIN LIMITATIONS

Because in several horses two approaches were tested consecutively, it cannot be excluded that the second TSP was performed at the previous puncture site. Due to the developmental nature of the study the approaches were not randomised and did not allow comparison.

CONCLUSION

Transseptal puncture is feasible in horses using ultrasound guidance and allows for electrophysiological exploration of the left heart. Further studies are needed to evaluate post-operative follow-up.

Transcatheter Cardiac Interventions in the Newborn: JACC Focus Seminar

For neonates with critical congenital heart disease requiring intervention, transcatheter approaches for many conditions have been established over the past decades. These interventions may serve to stabilize or palliate to surgical next steps or effectively primarily treat the condition. Many transcatheter interventions have evidence-based records of effectiveness and safety, which have led to widespread acceptance as first-line therapies. Other techniques continue to innovatively push the envelope and challenge the optimal strategies for high-risk neonates with right ventricular outflow tract obstruction or ductal-dependent pulmonary blood flow. In this review, the most commonly performed neonatal transcatheter interventions will be described to illustrate the current state of the field and highlight areas of future opportunity.

Retrograde Pulmonary Vein Recanalization Using Transcatheter Electrosurgery

Transcatheter electrosurgery is a wire-based technique used to traverse or cut tissue within blood-filled spaces using alternating current delivered by guidewires or catheters. The use of transcatheter electrosurgical techniques in the pediatric population has been limited. We are reporting the first case of retrograde pulmonary vein recanalization using transcatheter electrosurgery. (Level of Difficulty: Advanced.)

Transcatheter Electrosurgery: JACC State-of-the-Art Review

Transcatheter electrosurgery refers to a family of procedures using radiofrequency energy to vaporize and traverse or lacerate tissue despite flowing blood. The authors review theory, simulations, and benchtop demonstrations of how guidewires, insulation, adjunctive catheters, and dielectric medium interact. For tissue traversal, all but the tip of traversing guidewires is insulated to concentrate current. For leaflet laceration, the "Flying V" configuration concentrates current at the inner lacerating surface of a kinked guidewire. Flooding the field with non-ionic dextrose eliminates alternative current paths. Clinical applications include traversing occlusions (pulmonary atresia, arterial and venous occlusion, and iatrogenic graft occlusion), traversing tissue planes (atrial and ventricular septal puncture, radiofrequency valve repair, transcaval access, Potts and Glenn shunts), and leaflet laceration (BASILICA, LAMPOON, ELASTA-Clip, and others). Tips are provided for optimizing these techniques. Transcatheter electrosurgery already enables a range of novel therapeutic procedures for structural heart disease, and represents a promising advance toward transcatheter surgery.

Transseptal puncture using surgical electrocautery in children and adults with and without complex congenital heart disease

BACKGROUND

Atrial transseptal puncture (TSP) for cardiac catheterization procedures remain challenging in children and adults with complex congenital heart disease (CHD).

OBJECTIVES

We sought to evaluate our experience using radiofrequency (RF) current via surgical electrocautery needle for TSP to facilitate diagnostic and interventional procedures.

METHODS

Retrospective chart review of all patients (pts) who underwent TSP using RF energy (10-25 W) via surgical electrocautery from three centers from January 2011 to January 2017 were evaluated. Echocardiograms were reviewed to define the atrial septum as normal and complex (thin aneurysmal, thick/fibrotic, synthetic patch material, and extra cardiac conduit).

RESULTS

A total of 54 pts underwent 55 successful TSP. Median age was 12.5 years (1 day-54 years) and weight was 52.7 kg (2-162). Indications for TSP included; EP study and ablation procedures in structurally normal hearts (n = 24) and in complex atrial septum/CHD and structural heart disease pts (n = 30): Electrophysiology study and ablation in 4, diagnostic catheterization in 9, and interventional procedures in 17 pts were performed. Atrial TSP was successful in 54/55 (98%). Atrial perforation with tiny-small pericardial effusion not requiring intervention was noted in 2 pts. TSP was unsuccessful in one critically ill neonate with unobstructed TAPVR and restricted atrial septum who experienced cardiac arrest requiring CPR, ECMO, and emergent surgery.

CONCLUSIONS

RF current delivery using surgical electrocautery for TSP is a feasible and an effective option in patients with complex CHD for diagnostic, interventional, and electrophysiology procedures.

Novel transatrial septoplasty technique for neonates with hypoplastic left heart syndrome and an intact or highly restrictive atrial septum

Two patients born with hypoplastic left heart syndrome and an intact or highly restrictive atrial septum requiring emergent intervention are presented. For both patients, rapid septoplasty was performed using a hybrid approach involving direct atrial puncture and transatrial cutting balloon dilation of the atrial septum. This technique facilitates safe and rapid procedural completion and minimizes the risk of procedural complications in this very-high-risk patient population.