Innovations in Clinical Cardiac Electrophysiology

By Raul Weiss

Director, Electrophysiology Fellowship Program Professor of Internal Medicine – Clinical
Ohio State University Wexner Medical Center


The year 2019 was a great year for the field of Clinical Cardiac Electrophysiology. There were many advances on many fronts. Some of them related to implanted cardiac devices and some of them related to ablation of atrial and ventricular arrhythmias.

In the field of ablation it is important to mention some of the new cardiac Mapping Systems or improvement of well-established systems.

Acutus Medical is a full-service electrophysiology company focused on developing innovative technologies that seek to provide physicians and patients with improved outcomes. The AcQMap® High Resolution Imaging and Mapping System provides static and dynamic 3D maps of real-time electrical activation across the chamber surface. The 48-ultrasound transducer catheter samples 115,000 surface points per minute to create anatomy within 3 minutes, while 48-electrodes measure the intracardiac field to provide low-noise and high-fidelity inputs. This is processed through an inverse solution which eliminates far-field blending, and in turn enables continuous display of the wave front.

Voltage mapping has been the standard of practice thus far, however it does not represent the most localized measure of activation. Charge density represents the actual biophysics of cardiac activation and provides the most specific and localized measure. This has been foundation of AcQMap’s technology. When applied globally and simultaneously, charge density mapping enables visualization of complex atrial arrhythmias such as atrial fibrillation. The future potential of this imaging platform enables mechanical measures such as cardiac function, tissue characterization, and secondary structures.

UNCOVER-AF is the first trial to investigate the use of AcQMap to guide ablation therapy in a prospective study of patients with persistent atrial fibrillation. UNCOVER-AF demonstrated a 72.5% single-procedure freedom from AF at 12 months. Post-ablation monitoring revealed 89.6% of the single-procedure patients experienced zero episodes of AF. Electrophysiologists are able to individualize care by discerning non-PV targets which are unappreciated by other systems. The ability to discern focal, rotational, and irregular activity empowers a physician to determine a tailored treatment strategy for each patient.

The goal at Acutus is to provide physicians with leading edge arrhythmia tools for customized patient care. AcQMap is engineered as an open-platform for integration with multiple partners and technologies to cater to physician preference and needs.

Also there is a large number of catheters for radiofrequency ablation being introduced. One of them, manufactured by Biosense Webster couple with a new RF delivery system and multiple thermocouple sensors in the tip of the catheter is worth mentioning. The new QDot Micro Ablation Catheter is designed to allow delivery of 90 watts for 4 seconds. The hope is to reduce procedural time and decrease recurrences by having a transmural lesion.

Alternative energy, like radiation, is gaining traction for the treatment of ventricular tachycardia that is refractory to radiofrequency ablation or medication. Although it is considered as the last resort currently, it may change in the future and become more “mainstream”. Even though the original work by Dr Philip S Cuculich was presented in the New England Journal of Medicine (NEJM) in 2018, now we have a small trial (19 patients) that shows promising results.

The use of implantable loops Recorders (ILRs) in 2019 continue to increase in utilization. An important study, conducted by our group and lead by Dr Muhammad Afzal, shows a high number of false positive transmissions for atrial fibrillation. This certainly increases health care resources utilization and have trigger ways to prevent them.

Another important milestone in 2019 was the approval by the FDA of the Optimizer. This device has shown beneficial effect in the treatment of symptomatic heart failure patients, not considered today to be candidates for resynchronization therapy and have mild. To moderate reduced ejection fraction.