Cardiac Radiosurgery for the Treatment of Atrial Fibrillation

Abstract

An estimated 4 million Americans currently have atrial fibrillation (AF), the most common form of cardiac arrhythmia. The annual growth rate of AF is approximately 9.2% and advanced statistical analyses project that the prevalence of AF will be 12.1 million in the United States by 2030. The current therapeutic options to treat AF put certain patient groups at a high risk for a serious bleeding event, stroke or thromboembolism, myocardial infarction, and death. The most effective treatment for AF-catheter ablation-has been widely reported to require repeat operations and only leaves 59.4% of patients AF-free after five years. A majority of the reported complications and increased risks for catheter ablation occur because the procedure is invasive. Thus, there is a need for a novel, non-invasive therapeutic option to treat AF that can potentially expand the treatable patient population, increase patient safety, and improve clinical outcomes. CyberHeart Inc. has been exploring the efficacy and potential of cardiac radiosurgery as an option to treat heart conditions such as AF. With its proprietary CardioPlan TM software, the CyberHeart System utilizes the Cyberknife stereotactic radiosurgery platform to non-invasively ablate the heart. Early studies have displayed that the CyberHeart System is highly accurate at delivering radiation to cardiac targets and effective at minimizing radiation exposure to healthy tissue that is in close proximity to the targeted anatomic region. The focus of this review is to present the current standard of treatment for AF, identify the specific patient population that is at a high risk for the current treatment modalities, and address the potential for the CyberHeart Stereotactic Radiosurgery System to noninvasively ablate cardiac tissue and return sinus rhythm to patients with AF.

Cost-Effectiveness of Cardiac Radiosurgery for Atrial Fibrillation: Implications for Reducing Health Care Morbidity, Utilization, and Costs

“…Rate control treatment methods for AF attempt to control heart rate, do not require invasive procedures, and usually use drugs with low toxicity [ 17 ]. Conventional rate control strategies will consist of drugs such as beta-blockers, calcium channel blockers, or digoxin [ 4 , 18 ]. For many patients, however, heart rate control is inadequate to improve the quality of life or ameliorate symptoms of heart failure.…”

“…For many patients, however, heart rate control is inadequate to improve the quality of life or ameliorate symptoms of heart failure. Rhythm control therapeutic regimens, the other strategy for AF management, attempt to restore sinus rhythm to the heart by using antiarrhythmic drugs (AADs) or invasive catheter ablation procedures [ 4 , 17 , 18 ]. Restoration of sinus rhythm is associated with improvement in physical functioning, general health, social functioning, and exercise performance [ 19 ].…”

Radiosurgical Ablation of the Renal Nerve in a Porcine Model: A Minimally Invasive Therapeutic Approach to Treat Refractory Hypertension

“…CyberHeart Inc. has pioneered the world’s first cardiac radiosurgery system (CRS) that can non-invasively ablate the heart with remarkable precision [9-10]. This innovative technology, which is anticipated to radically improve clinical outcomes for the millions of patients with cardiac arrhythmia, uses the CyberKnife (Accuray, Inc., Sunnyvale, CA, USA) radiosurgical platform to accurately transmit radiation to cardiac targets [9-10].…”

“…This innovative technology, which is anticipated to radically improve clinical outcomes for the millions of patients with cardiac arrhythmia, uses the CyberKnife (Accuray, Inc., Sunnyvale, CA, USA) radiosurgical platform to accurately transmit radiation to cardiac targets [9-10]. Given the exceptional degree of precision that the CyberHeart (CyberHeart Inc., Mountain View, CA, USA) CRS has displayed to date, it can be anticipated that the CyberHeart radiosurgery system (RS) has a promising potential to non-invasively ablate the renal nerve and provide a treatment for hypertension.…”

Analysis of Dose Distribution in the Heart for Radiosurgical Ablation of Atrial Fibrillation

“…Tests of this technique have included phantom studies and animal studies [ 1 - 3 ]. This method has been used in humans for treatment of both ventricular tachycardia [ 4 ] and atrial fibrillation [ 5 ].…”