Stages of Procedural Development

There have been five distinct development stages to allow the procedure evolution leading to the Standardized Convergent Procedure. The development stages included pre-clinical studies, open chest concomitant surgical, minimally invasive surgical, the convergent procedure and our present stage of development, the standardization of the Convergent Procedure.

I. Pre-clinical Studies: Complete Linear Lesions

The Company began by developing technology that could create long linear visible lesions that are connected to form a comprehensive lesion pattern modeled after the Maze pattern. Critical to the device was its design specifically for endoscopic approaches through port or needle stick access. The pre-clinical studies demonstrated complete, visible lesions could be created in animals to a consistent depth of 7mm.

Literature: Kiser A, et al. Evaluation of a Novel Epicardial Atrial Fibrillation Treatment System. Ann Thorac Surg 2008;85:300–4

Ventricle Tachycardia Preclinical Literature: Valderrabano M, et al. Creating Transmural, Linear Epicardial Ablation Lesions via a Non-surgical, Percutaneous, Subxyphoid, Electrogram-guided Approach.The Journal of Innovations in Cardiac Rhythm Management, 3 (2012), 647-653.

II. Concomitant Surgical Studies: Designing a Comprehensive Lesion Pattern

The first procedure was performed on concomitant patients, typically coming for mitral repair surgery. The procedure was performed through a sternotomy and a comprehensive, bi-atrial external Maze pattern was applied. The pattern represented a consensus opinion of European and American cardiac surgeons. Of the first 20 patients undergoing the procedure, 16 converted to sinus rhythm intra-operatively. Functionally, the lesion pattern has remained a constant throughout the stages of procedural evolution, and thus, the efficacy of the pattern has been fairly consistent throughout the stages of procedure evolution.

Literature: Gersak B, et al. Importance of evaluating conduction block in radiofrequency ablation for atrial fibrillation. Eur J Cardiothorac Surg (2011), doi: 10.1016/j.ejcts.2011.05.025

III. Minimally Invasive Surgical Studies: SUBTLE™ Access and Right Sided Chest Ports

One of the most important developments in the procedure evolution was access to the posterior of the atria through trans-diaphragmatic access. This access came to be known as SUBTLE™ access, or sub-thoracic, total endoscopic access. Our technical dilemma was being able to create the same lesion pattern through the abdomen to eliminate chest incisions. The combination of right sided ports and SUBTLE access allowed surgeons to replicate the lesion pattern. Practical problems became clear; the procedure was complex requiring chest incisions, lung deflation and heart dissections. The lesion pattern had to be paced at high amplitude to assure lesion completeness, pattern connectivity and pulmonary vein isolation to assure success. Cardiologists would not refer to such an invasive approach.

Literature:

IV. Convergent Procedure; Multi-Disciplinary Approach Involving EPs

With EP participation, the procedure evolved significantly because as electrical experts, they immediately simplified the lesion pattern to maintain function while eliminating extraneous lesions. Consequently, the new lesion pattern could be applied by surgeons solely through the SUBTLE™ access. Additionally, the EPs provided the sophisticated diagnostics combined with the endoscopic ablation capabilities to ensure lesion completeness, pattern connectivity and electrical isolation. The multi-disciplinary approach combined best techniques and technologies to create a complete procedure with checks and balances to predict outcomes.

Literature and Graphical Data Summaries:

V. Standardizing the Convergent Procedure & Multi-disciplinary Practices

As a device company enabling new procedures, the Company has responsibility for use of its device in medical practice, but physicians have full discretion to use the technology as they see fit. Consequently, physicians have used the technology in a variety of ways to create new lesion patterns, or augment existing ablation practices. There are ablation limitations and studies will demonstrate that less endocardial ablation, particularly on the posterior, is potentially safer, and the combined approach can create a viable treatment alternative for AF patients with enlarged atria and structural heart disease. Both surgeons and EPs are working toward consensus to standardize protocols for their portions of the total procedure to maximize safety and efficacy. A standardized procedure may increase adoption as results should be consistent between sites.

VI. Futures - Ventricle Tachycardia

The device has further application in other arrhythmias, including ventricle tachycardia ("VT"). At this writing, the company has completed pre-clinical animal studies, and will participate in a European trial to ascertain the device effectiveness in epicardial VT ablation. The Company has received CE Mark approval for the treatment of atrial fibrillation for its new device design which includes embedded electrodes to sense, allowing for epicardial mapping and navigation.

Literature: Valderrabano M, et al. Creating Transmural, Linear Epicardial Ablation Lesions via a Non-surgical, Percutaneous, Subxyphoid, Electrogram-guided Approach.The Journal of Innovations in Cardiac Rhythm Management, 3 (2012), 647-653.

Disclaimer: Individual patient results may vary from the literature, including those posted here. A detailed discussion between patient and physician is essential to optimize both expectations and results.