Convergent Plus Procedure Gets the Robotic Treatment

Convergent Plus is an innovative hybrid treatment for persistent and long-standing persistent atrial fibrillation (AF). It combines minimally invasive epicardial and endocardial ablation to achieve rhythm control along with left atrial appendage occlusion (LAAO) to further reduce stroke risk.

This novel treatment started gaining traction around 2020 and has since been performed using a robotic-assisted approach at just a handful of U.S. centers, including Cleveland Clinic Weston Hospital. Cardiothoracic surgeon José L. Navia, MD, FACC, recently participated in Cleveland Clinic’s first case of robotic Convergent Plus for a 41-year-old male with persistent AF.

“The patient suffered with significant AF burden resulting in multiple ER admissions,” says Dr. Navia, who serves as Vice Chief of the Heart, Vascular & Thoracic Institute for Cleveland Clinic in Florida and Chairman of Cardiothoracic Surgery for the five-hospital regional health system. “Because he failed to receive symptom relief with antiarrhythmic drugs and catheter ablation, he was a good candidate for Convergent Plus.”

Robotic-assisted surgical ablation

Surgical epicardial ablation is the first step of the Convergent Plus procedure. The robotic-assisted approach performed by Dr. Navia, using the Da Vinci Xi™ surgical system, is a novel technique that provides more direct access to the left atrium.

“Unlike the subxiphoid and transdiaphragmatic approaches, the left lateral approach using the robotic platform allows for better access and targeting of more areas of the left atrium known to generate arrhythmogenic electrical activity,” explains Dr. Navia. “It also allows me to easily occlude the left atrial appendage concomitantly using the same access point.”

The surgery requires three 8 mm ports in the left chest for placement of two robotic arms and a scope for thoracoscopic visualization. Another 12 mm working port is used for introducing and manipulating the electrophysiological mapping and radio frequency (RF) ablation probes. Following the ablation procedure, the working port is then used as the access point for the left atrial appendage (LAA) clipping device.

According to Dr. Navia, a key advantage of the robotic-assisted approach is the enhanced three-dimensional (3D) high-definition visualization. “I can perfectly see the surgical field and avoid damage to nearby structures, including the phrenic nerves and the central circulation, while minimizing retraction of the heart,” he describes.

Dr. Navia says the patient also experiences less postoperative pain, a shorter postoperative length of stay, a faster recovery, and a better cosmetic result with this approach.

Achieving electrical silence

While pulmonary veins are known foci for AF inducing signals, studies have shown that pulmonary vein isolation (PVI) alone is less effective for restoring sinus rhythm in cases of persistent AF. “That’s why we also ablate non-pulmonary vein structures,” says Dr. Navia.

To identify the atrial regions with abnormal electrical activity, Dr. Navia’s team performed intraoperative 3D electrophysiological mapping. In this case, the left atrial posterior wall, the roofline of the left atrium, the ligament of Marshall, and the coumadin ridge were targeted in addition to the pulmonary veins. Further, after each lesion was created on the surface of the heart using the RF probe, additional voltage measurements were taken to ensure electrical silence at the lesion site.

Because esophageal injury is a known complication of epicardial ablation, the ablation sites were irrigated with cool sterile saline and continuous luminal esophageal temperature (LET) monitoring was performed throughout the procedure. “If the temperature probe senses a change of 0.5°C, the ablation is immediately stopped to prevent thermal injury,” notes Dr. Navia.

Elevated stroke risk

Following completion of the ablation procedure, the next step in Convergent Plus is to occlude the LAA. About 90% of strokes originating in an upper heart chamber start in the LAA, and research has shown that removing or blocking the LAA significantly reduces stroke risk. For that reason, LAAO has garnered a Class I recommendationfrom the Society of Thoracic Surgeons for all patients with AF undergoing first-time, nonemergent cardiac surgery.

“Patients with AF are five times more likely to suffer an embolic stroke, making stroke prevention an important component of AF management,” explains Dr. Navia. “Epicardial exclusion with a linear clip device offers reliable closure, regardless of LAA size or depth, and proven stroke risk reduction.”

Preoperative transesophageal echocardiogram (TEE) was used to measure the dimensions of the LAA and select the correct device and size to achieve a good seal. Dr. Navia used a AtriClip ProV™ device for this patient. It was introduced through the working port and positioned at the base of the appendage. Additional imaging was used to verify the correct placement, successful closure and to confirm hemostasis.

Catheter-based ablation

As the final step of the Convergent Plus procedure, catheter-based endocardial ablation was performed by an electrophysiologist approximately a month later to complete the lesion set and electrically isolate the pulmonary veins and posterior wall.

“The combination of epicardial and endocardial ablation ensures durable transmural lesion sets that provide lasting symptom relief for patients with persistent AF,” reports Dr. Navia. “In this case, the patient had no complications and is doing very well.”

Dr. Navia also points out that for some patients the addition of the LAAO procedure may eliminate the need for the lifelong use of anticoagulants, though these decisions are made on a case-by-case basis.