Cardiac Ablation Catheters Generic Arrhythmia Indications for Use; Guidance for Industry
Document issued on: July 1, 2002
This document supersedes Cardiac Ablation
Catheters Generic Arrhythmia Indications for Use;
Draft Guidance for Industry, issued December 07, 2001
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U.S. Department of Health and Human Services Cardiac Electrophysiology and Monitoring Branch
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Comments and suggestions may be submitted at any time for Agency consideration to Dockets Management Branch, Division of Management Systems and Policy, Office of Human Resources and Management Services, Food and Drug Administration, 5630 Fishers Lane, Room 1061, (HFA-305), Rockville, MD, 20852. When submitting comments, please refer to Docket No. 01D-0519. Comments may not be acted upon by the Agency until the document is next revised or updated.
For questions regarding the use or interpretation of this guidance contact Randall Brockman, Office of Device Evaluation, HFZ-450, 9200 Corporate Boulevard, Rockville, MD 20850, (240) 276-4080, or email randall.brockman@fda.hhs.gov.
Additional copies are available from the Internet at: http://www.fda.gov/cdrh/ode/guidance/1382.pdf, or CDRH Facts-on-Demand. In order to receive this document via your fax machine, call the CDRH Facts-On-Demand system at 800-899-0381 or 301-827-0111 from a touch-tone telephone. Press 1 to enter the system. At the second voice prompt, press 1 to order a document. Enter the document number (1382) followed by the pound sign (#). Follow the remaining voice prompts to complete your request."
Cardiac Ablation Catheters Generic Arrhythmia Indications for Use; Guidance for Industry
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This document is intended to provide guidance. It
represents the Agency's current thinking on this topic. It does not create
or confer any rights for or on any person and does not operate to bind
the Food and Drug Administration (FDA) or the public. An alternative approach
may be used if such approach satisfies the requirements of the applicable
statute and regulations.
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During the past 10 years, catheter-based radiofrequency (RF) ablation has rapidly become the standard of care for patients with certain cardiac arrhythmias, and devices used to perform this procedure have been extensively studied. Most marketed devices are of a similar design and are intended to create endocardial lesions. The safety and effectiveness of these Class III devices for treating many common arrhythmias has been reported and is now well characterized in the medical literature.1-12
Because of our understanding of the safety and effectiveness of these devices for a wide variety of arrhythmias, the Center for Devices and Radiological Health (CDRH) of the Food and Drug Administration (FDA) is encouraging manufacturers of approved conventional RF ablation catheters to submit a PMA supplement to revise their indications statement from an arrhythmia-specific indication to a generic arrhythmia treating indication. The purpose of this document is to provide support for FDA's recommendation to label approved conventional RF ablation catheters for the generic indication of treating cardiac arrhythmias. The recommendations discussed in this document are limited to the use of RF catheters for treating cardiac arrhythmias with ablation, and not for any other treatment modality.
Based on the review of the medical literature, FDA defines conventional RF cardiac ablation catheters as those that have the following features:
Conventional RF ablation catheters have been previously approved by the FDA for treating supraventricular tachycardias (SVTs) including the following:
To obtain premarket approval of a conventional RF ablation system, it is currently necessary for a manufacturer to perform a prospective clinical study to collect data that demonstrate a reasonable assurance of the safety and effectiveness of the ablation system for treating a specified arrhythmia. Typically, the evaluated endpoints have included Acute Success, Chronic Success (3-6 Month Success), and Safety (occurrence rate of major complications). Table 1 below provides estimates of target values and confidence boundaries for these study endpoints (based on current medical literature). For the above specific indications, it has been acceptable for the sponsor to statistically compare the clinical performance of its investigational ablation system to clinical data reported in the medical literature.
Table 1. Acceptable Endpoint Criteria Based on Medical Literature
| STUDY ENDPOINT | TARGET VALUE | 95 % CONFIDENCE BOUND |
|---|---|---|
| Acute Success | > 95 % | >= 85 % |
| Chronic Success | > 90 % | >= 80 % |
| Major Complications | < 2.5 % | <= 7 % |
RF ablation catheters for the treatment of cardiac arrhythmias are a mature technology. The biophysics of RF lesion creation when using conventional RF technology is also well characterized and predictable as reported in the medical literature.13-15
There is extensive medical literature reporting the safe and effective use of conventional RF ablation catheters for treating a variety of arrhythmias in addition to those listed above. Table 2 shows data pooled from the medical literature on three arrhythmias to specifically illustrate different ablation techniques. Literature data for these arrhythmias were chosen to demonstrate the safety and effectiveness of using conventional RF catheters to create either focal or linear lesions in any of the four chambers of the heart. Existing data for the treatment of these three arrhythmias are discussed in more detail below.
Table 2: Safety and Effectiveness of RF Ablation Using Conventional RF Ablation Catheters
| ARRHYTHMIA | N | ACUTE SUCCESS | CHRONIC SUCCESS | COMPLICATIONS | COMMENTS |
|---|---|---|---|---|---|
| Atrial Flutter1,6-8,10,11,16 | 1437 | 72 - 100% | 85-100% | 0 - 6% | Linear lesions across isthmus |
| Ventricular Tachycardia 10,11,16 | 1463 | 66 - 85% | 86% | 2 - 8% | Right and left ventricles |
| Atrial Tachycardia 4,16 | 494 | 91% | 85% | 3% | Right and left atria |
Atrial Flutter
Atrial flutter is usually a well defined macro-reentrant circuit with the critical
zone defined as the isthmus between the tricuspid valve and the inferior vena
cava. Radiofrequency ablation of atrial flutter in this location with the creation
of a linear lesion across the tricuspid isthmus has proven to be successful
in the majority of patients treated. This technique using RF ablation is becoming
a first line therapy for atrial flutter with highly predictable results. In
the 1998 North American Society for Pacing and Electrophysiology (NASPE) Prospective
Catheter Ablation Registry,16 477 patients were treated with RF ablation for
atrial flutter. The major complication rate was less than 3% and included bleeding/hematoma
(3 patients), cardiac tamponade
(1 patient), hemopneumothorax (1 patient), new tricuspid regurgitation (1 patient),
hypoxia
(1 patient), and hypotension (1 patient).
Ventricular Tachycardia
Patients being treated with RF ablation for ventricular tachycardia (VT) usually
have either ischemic VT or "normal heart" VT. Patients with ischemic
VT often have multiple co-morbidities and have undergone various other treatment
modalities, including multiple antiarrhythmic medications. Radiofrequency ablation
of VT requires placement of the catheter in either the right or the left ventricle
depending on the underlying substrate. Acute and chronic success rates are variable
because patients often have multiple VT morphologies, especially in ischemic
heart disease patients where the underlying disease substrate is progressive.
Radiofrequency ablation procedures for "normal heart" VT are often
curative, whereas procedures for ischemic VT are often palliative (i.e., reduces
the number of implantable cardioverter defibrillator discharges for ventricular
tachycardia episodes). In the 1998 NASPE Prospective Catheter Ablation Registry,16
299 patients were treated with RF ablation for VT. The major complication rate
was 3.8% and included cardiac tamponade (2 patients), respiratory failure (1
patient), sepsis (1 patient), worsening congestive heart failure (2 patients),
and pericarditis (1 patient).
Atrial Tachycardia
A third atrial arrhythmia commonly treated with RF ablation is atrial tachycardia (AT). Radiofrequency ablation of AT usually involves creating a focal lesion in either the right or left atrium. Electrophysiologic mechanisms of AT include automaticity, triggered automaticity, and reentry. Success rates vary because of the heterogenicity of this arrhythmia. In the 1998 NASPE Prospective Catheter Ablation Registry,16 there were 216 patients that had atrial tachycardia ablations and the major complication rate was 3%. The reported complications were cardiac tamponade (2 patients), transient AV block (1 patient), aspiration pneumonia (1 patient), and right atrial to aortic fistulae (1 patient).
Under the American College of Cardiology/American Heart Association (ACC/AHA) Guidelines for Clinical Electrophysiological and Catheter Ablation Procedures,12 RF ablation is given a Class I indication for the treatment of many tachyarrhythmias. Class I indications are defined as the preferred treatment modality by general agreement in the medical community. The ACC/AHA guidelines are widely accepted and have been adopted into current medical practice and are included in training programs for cardiac electrophysiology.
The combination of published safety and effectiveness data and the published ACC/AHA guidelines for medical use provide persuasive evidence to support a generic arrhythmia indication. FDA encourages manufacturers of approved conventional RF ablation catheters to submit a PMA supplement to revise their indications statement from arrhythmia-specific indications to a generic arrhythmia treatment indication, such as:
Creating endocardial lesions during cardiac ablation procedures to treat arrhythmia.
The PMA supplement should describe any labeling changes to be made as a result of the generic indications.
If the manufacturer intends to indicate the device for treatment of a cardiac arrhythmia other than those described above, supportive clinical information may be required.
In conclusion, FDA is now suggesting that manufacturers of approved conventional RF ablation catheters consider submitting a PMA supplement to revise their indications statement from an arrhythmia-specific indication to a generic arrhythmia treating indication. FDA believes that product-specific clinical data for specific arrhythmias along with available literature data support a more generic arrhythmia treating indication for conventional RF cardiac ablation catheters.
Updated July 1, 2002
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