SUMMARY of SAFETY and EFFECTIVENESS DATA

# General Information

**Device Generic Name:** Cardiac Ablation Catheter

**Device Trade Name:** Stinger™ Ablation Catheter

TempLink™ Extension Cable

**Name & Address of Sponsor:** C.R. Bard, Inc., Electrophysiology
Division

> 55 Technology Drive

Lowell, MA 01851

**PMA Application Number:** P000020

**Date of Panel Recommendation:** N/A

**Date of Notice of Approval to the Applicant:** November 29, 2000

# Indications for Use

The Stinger™ Ablation catheter is indicated for creating focal
endocardial lesions during cardiac ablation procedures to treat
arrhythmias; and for cardiac electrophysiological mapping and delivering
diagnostic pacing stimuli.

The TempLink™ extension cable when used in conjunction with a thermistor
configured Stinger Catheter is indicated for use during cardiac ablation
with set power up to 50W

# ContraindicaTIons

• The catheter should not be used in conditions where manipulation of
the catheter would be unsafe (e.g. intracardiac mural thrombus).

• The transseptal approach is contraindicated in patients with left
atrial thrombus or myxoma, or interatrial baffle patch.

• The retrograde transaortic approach is contraindicated in patients
with aortic valve replacement.

There are no known contraindications for the use of the TempLink
extension cable.

# Warnings and Precautions

See [**Warnings and Precautions**]{.smallcaps} in the professional
labeling (Information for Use)

# Device Description

The device consists of the Stinger™ Ablation Catheter and the TempLink™
Extension Cable, described below. These components are used in
conjunction with a compatible RF generator to deliver RF energy to
endocardial structures in the treatment of cardiac arrhythmias. The
specifications for a compatible RF generator are listed below.

## 5.1 STINGER™ Ablation catheter {#stinger-ablation-catheter .unnumbered}

Bard Electrophysiology Stinger™ Ablation catheter is a radiopaque,
flexible, insulated catheter with a polymer shaft. The catheter handle
has a slider mechanism which, when moved forward or back from the
neutral position, results in curvature of the distal tip. The Stinger™
Ablation catheter is available in six (6) different curve configurations
designated "A" through "F" as shown in Table 1 below. For ablation, the
distal tip delivers up to 50W of radiofrequency (RF) energy when used in
conjunction with a compatible RF generator.

The Stinger Diagnostic/Ablation catheter is a 7F quadpolar electrode
catheter, configured with a 4mm distal electrode and three 1mm proximal
electrodes with 2mm/5mm/2mm interelectrode spacing. The distal electrode
delivers radiofrequency energy from the generator and is equipped with a
thermistor-type temperature sensor to allow for physician monitoring and
control of electrode temperature. The catheter has bi-directional tip
curvature within a single plane. Steering of the distal tip section is
accomplished by pushing or pulling a slide tab on the handle, which
activates either of two pullwires to deflect the tip in the desired
direction. The steerability feature is intended to provide a means of
localizing and maintaining contact at the intended ablation site(s),
with an adjunctive benefit of being able to straighten the catheter from
a curve once the curve has been formed.

#### Table 1. Summary Table of Catheter Models and Features {#table-1.-summary-table-of-catheter-models-and-features .unnumbered}

![](media/image1.wmf){width="5.047916666666667in"
height="2.865972222222222in"}

## 5.2 TEMPLINK™ EXTENSION CABLE {#templink-extension-cable .unnumbered}

The TempLink Extension cable acts as an extension cord for connection of
the catheter to various EP lab devices that include commercially
available ECG monitor/recorders and stimulators. The TempLink extension
cable also mates with compatible RF generators via a protected pin
design. The cable has a keyed connector that fits the catheter
connector. The key ensures that the catheter electrodes are connected to
the cable such that the identification on the cable tails corresponds to
the position of the electrode (or thermistor) from the tip of the
catheter (i.e., D for distal electrode, 2 for the next proximal
electrode, etc. and T for thermistor lead). The cable is offered in 4
foot and 7 foot lengths.

## 5.3 COMPATIBLE RF GENERATOR  {#compatible-rf-generator .unnumbered}

The Stinger™ Ablation Catheter should be used only with a legally
marketed RF generator which has been shown to be safe and effective for
cardiac ablation, and which is compatible with the specifications of the
catheter and extension cable. Specifications for Compatible RF
Generators are listed in Table 2, below.

#### Table 2. Specifications for Compatible RF Generators {#table-2.-specifications-for-compatible-rf-generators .unnumbered}

+---------------------------------+------------------------------------+
| **Generator Feature**           | **Specification**                  |
+---------------------------------+------------------------------------+
| Thermometry                     | Thermistor                         |
+---------------------------------+------------------------------------+
| Temperature Limit, Maximum      | 95 C                               |
+---------------------------------+------------------------------------+
| Modes:                          | Temperature Control                |
|                                 |                                    |
| (must operate in all 3 modes)   | Temperature Monitoring             |
|                                 |                                    |
|                                 | Power Control                      |
+---------------------------------+------------------------------------+
| Maximum Output Power            | 50 Watts                           |
+---------------------------------+------------------------------------+
| RF Output Frequency             | 450 kHz-550 kHz                    |
+---------------------------------+------------------------------------+
| Impedance Cut-off               | High: 300 ohms                     |
|                                 |                                    |
|                                 | Low: 50 ohms                       |
+---------------------------------+------------------------------------+

# Alternative Practices and Procedures

Therapeutic options for patients with arrhythmias are dependent upon the
specific arrhythmia that is present. For many arrhythmias, an
alternative practice is antiarrhythmic drug therapy. Depending on the
type of arrhythmia, alternative practices and procedures may also
include surgery, pacing therapies, or implantable
cardioverter-defibrillators (ICD).

# Marketing History

The Stinger™ Ablation Catheter and TempLink™ Extension Cable have been
marketed since early 1998 in European and Latin Pacific countries, and
Australia and New Zealand. The Stinger catheter and TempLink cable have
not been withdrawn from marketing in any country for any reason related
to safety and effectiveness.

# Adverse Events

1.  **Observed Adverse Events**

Adverse events that were observed during the U.S. clinical trial of the
Stinger™ Ablation Catheter and TempLink™ Extension Cable are shown in
Table 3 below. A total of 13 major adverse events were reported for 11
patients. These events included transient complete heart block and
transient heart block, first degree AV block, tamponade from RV
perforation, cardiac arrest, pericardial effusion, heart failure, CVA,
atrial lead microdisplacement, acute renal failure, pneumonia, fever,
and a sudden onset of severe back, chest and upper abdominal discomfort.

**Table 3. Adverse Events - Major, Procedural Minor, and Deaths**

Population: All Patients Enrolled (N=251)

  --------------------- --------------- ---------------- ----------------
                        Number of       Number of        Percent of
                        Events          Patients         Patients

  Major Events          13              11/251           4.4%

  Procedural Minor      37              29/251           11%
  Events                                                 

  Patients Deaths       3               3/251            1.2%
  --------------------- --------------- ---------------- ----------------

Three (3) patients died during the study. None of the deaths were
considered related to the use of the study device.

2.  **Potential Adverse Events**

Adverse events (in alphabetical order) which may be associated with
catheterization and ablation include, but are not limited to:

• anaphylaxis (allergic reaction) with breathing problems, drop in blood
pressure and possibly death

• angina (chest discomfort)

• arrhythmia (irregular heartbeat)

• arterial/venous thrombosis (clot formation on the inside wall of the
artery at the entry site)

• AV fistula (a communication between the artery and vein at the site of
catheter insertion)

• back pain and/or groin pain

• cardiac perforation (hole in the lining of the heart)

• hematoma formation (bruise or bleeding into body tissue) in groin area

• hypotension (fall in blood pressure)

• infection

• myocardial infarction (heart attack)

• pericardial effusion or cardiac tamponade (collection of blood in
lining of the heart)

• pneumothorax (an accumulation of air or gas in the pleural space)

• significant blood loss which may lead to blood transfusion

• skins burns (injury to the skin caused by the electrical current)

• thrombotic events including stroke and pulmonary emboli

• unintentional complete heart block requiring a pacemaker

• vessel wall or valvular trauma which may lead to surgical repair

# Summary of Preclinical Studies

Non-clinical bench testing and animal testing have been conducted to
demonstrate the safety, reliability and performance of the Stinger
Ablation System. The following sections summarize the results of this
testing.

## 9.1 Non--Clinical Laboratory Studies  {#nonclinical-laboratory-studies .unnumbered}

### Bench Testing -- Stinger Ablation Catheter: Biocompatibility 

The patient contacting materials in the device include Pebax,
polyethylene, stainless steel, platinum, barium sulfate, bismuth
subcarbonate and epoxy**.** Finished, EtO sterilized devices were
subjected to biocompatibility testing in accordance with the
requirements of ISO 10993. The tests performed and the results are given
in Table 4 below.

**Table 4. Biocompatibility testing performed with the device.**

+-------------------------+--------------------------------------------+
| **Test**                | **Result**                                 |
+=========================+============================================+
| **CYTOTOXICITY** --     | MEM test extracts showed no evidence of    |
| conducted in accordance | causing cell lysis or toxicity. The        |
| with ISO 10993-5        | negative controls, reagent controls, and   |
|                         | positive controls performed as             |
|                         | anticipated.                               |
+-------------------------+--------------------------------------------+
| **SENSITIZATION**,      | Under the conditions of the study, the SC  |
| Guinea Pig,             | and CSO test article extracts showed no    |
| maximization method     | evidence of causing delayed dermal contact |
| (ISO 10993-10)          | sensitization in the guinea pig.           |
+-------------------------+--------------------------------------------+
| **IRRITATION**, Acute   | Under the conditions of the study, there   |
| intracutaneous          | was no evidence of significant irritation  |
| reactivity study,       | or toxicity from the extracts injected     |
| rabbit (ISO 10993-10)   | intracutaneously into rabbits.             |
+-------------------------+--------------------------------------------+
| **TOXICITY**, Acute     | Under the conditions of the study, the     |
| systemic toxicity,      | test article extracts would not be         |
| mouse (ISO 10993-11)    | considered systemically toxic to the mouse |
|                         | at the prescribed dosage. Each test        |
|                         | article extract met the ISO requirements.  |
+-------------------------+--------------------------------------------+
| **HEMOCOMPATIBILITY**   | 1.  The negative and positive controls     |
|                         |     performed as anticipated. The test     |
| 1.  Hemolysis           |     article was non-hemolytic              |
|                         |                                            |
| 2.  Coagulation (ISO    | 2.  The coagulation time of the plasma     |
|     10993-4)            |     after exposure to the test article was |
|                         |     within the expected coagulation time   |
| 3.  In Vivo             |     of the plasma control.                 |
|     Thrombo-resistance  |                                            |
|     (ISO 10993-4)       | 3.  After 4 hours of implantation, the     |
|                         |     test article exhibited minimal to      |
| 4.  Complement          |     moderate thrombus formation. Thrombus  |
|     Activation          |     formed on the blue portion of the      |
|                         |     catheter shaft, not the distal tip.    |
|                         |     There appeared to be no changes in the |
|                         |     hematologic and coagulation            |
|                         |     parameters.                            |
|                         |                                            |
|                         | 4.  The test article exhibited activation  |
|                         |     at 13,710 ng/ml. This was 10% of the   |
|                         |     normalized C3a concentration produced  |
|                         |     by the positive reference control      |
|                         |     material. The low control, human       |
|                         |     serum, positive control, and reference |
|                         |     control materials performed as         |
|                         |     anticipated.                           |
+-------------------------+--------------------------------------------+
| **PYROGENICITY** (ISO   | The total rise of rabbit temperatures      |
| 10993-11)               | during the 3-hour observation period was   |
|                         | within the acceptable USP limits. The      |
|                         | extract was judged non-pyrogenic.          |
+-------------------------+--------------------------------------------+

The biocompatibility of the catheter handle was evaluated separately
since this component does not contact the patient or patient fluids. The
sponsor performed a cytotoxicity study (the test article was judged
non-cytotoxic) and a physico-chemical study to characterize the
non-volatile residue, residue on ignition, heavy metals and buffering
capacity of the test article.

> **\
> 9.1.2 Bench Testing: Electrical and Mechanical\
> **

Fourteen catheters were subjected to conditioning and testing, going
from the least-destructive tests to the most destructive tests.
Conditioning consisted of 1X sterilization, accelerated aging
representing six months, temperature and humidity cycling (in accordance
with IEC 601-1 Part I, §10.1; and IEC 68-2-30 Part 2, Figures 1 and 2a),
and shipping and drop-test pre-conditioning (per NSTA Project 1A).

Table 5. Electrical and Mechanical Bench Tests

+---------------+---------------+-----------------+-------------------+
| **[Test       | ###### Meth   | ####### Pass/F  | #####             |
| Description]{ | ods {#methods | ail Criteria {# | ### Results {#res |
| .smallcaps}** |  .unnumbered} | passfail-criter | ults .unnumbered} |
|               |               | ia .unnumbered} |                   |
| **[(N=14      |               |                 |                   |
| ]{.smallcaps} |               |                 |                   |
| unless        |               |                 |                   |
| otherwise     |               |                 |                   |
| specified[)]{ |               |                 |                   |
| .smallcaps}** |               |                 |                   |
+===============+===============+=================+===================+
| > Radiopacity | >             | > Radiographic  | > All 5 samples   |
| > **(N=5)**   |  Radiographic | > density had   | > exceeded the    |
|               | > density of  | > to meet or    | > image density   |
|               | > images were | > exceed that   | > of the marketed |
|               | > compared to | > of either a   | > catheter in the |
|               | > a marketed  | > marketed      | > proximal shaft  |
|               | > catheter    | > catheter or   | > section, but    |
|               | > (Cordis     | > of a          | > were less       |
|               | > Corp.)      | > calibration   | > opaque in the   |
|               |               | > standard.     | > distal shaft    |
|               |               |                 | > section. The    |
|               |               |                 | > distal shaft    |
|               |               |                 | > section         |
|               |               |                 | > compared        |
|               |               |                 | > favorably to a  |
|               |               |                 | > calibration     |
|               |               |                 | > standard.       |
|               |               |                 | > Electrodes were |
|               |               |                 | > clearly         |
|               |               |                 | > visible.        |
+---------------+---------------+-----------------+-------------------+
| > Tip Cycling | > Catheter    | > Visual        | > All samples     |
|               | > subjected   | > inspection    | > passed with no  |
|               | > to 125 tip  | > must          | > degradation in  |
|               | > steering    | > demonstrate   | > steering        |
|               | >             | > mechanical    | > performance.    |
|               |  deflections, | > integrity.    |                   |
|               | > plus 20     |                 |                   |
|               | > cycles      |                 |                   |
|               | > manual      |                 |                   |
|               | > flexion of  |                 |                   |
|               | > the shaft.  |                 |                   |
+---------------+---------------+-----------------+-------------------+
| > Ablation    | > Specimens   | > Visual        | > All samples     |
| >             | > were        | > inspection    | > passed with no  |
|  Conditioning | > subjected   | > and           | > sign of tip     |
|               | > to 35 RF    | > dimensional   | > tubing          |
|               | > ablations   | > measurements  | > swelling.       |
|               | > with        | > of tip to     |                   |
|               | > catheter    | > determine if  |                   |
|               | > tip fully   | > swelling of   |                   |
|               | > deflected   | > the tip       |                   |
|               | > and         | > tubing        |                   |
|               | > submerged   | > occurred.     |                   |
|               | > in 37 C     |                 |                   |
|               | > saline      |                 |                   |
|               | > bath.       |                 |                   |
+---------------+---------------+-----------------+-------------------+
| > Tip to      | > Specimens   | > Visual        | > Subsequent      |
| > Tip-Stock   | > exposed to  | > inspection    | > electrical      |
| > Torque      | > rotational  |                 | > testing         |
| >             | > forces of   |                 | > revealed no     |
|  Conditioning | > 45 .        |                 | > functional      |
|               | > Designed to |                 | > failures.       |
|               | > simulate    |                 |                   |
|               | > cleaning    |                 |                   |
|               | > stresses.   |                 |                   |
+---------------+---------------+-----------------+-------------------+
| > Seal        | > Exposed     | > (Performance  | > (Performance of |
| > Integrity   | > specimens   | > not           | > catheters       |
|               | > to a        | > specifically  | > established in  |
|               | > pressurized | > tested)       | > subsequent      |
|               | > soak        |                 | > tests)          |
|               | > condition,  |                 |                   |
|               | > for a       |                 |                   |
|               | > minimum of  |                 |                   |
|               | > 15 hours.   |                 |                   |
+---------------+---------------+-----------------+-------------------+
| > Circuit     | > Measured    | > Resistance    | > All samples     |
| > Resistance  | > circuit     | > 3.5 Ohms      | > passed.         |
| > and         | > resistance  | >               |                   |
| > Isolation   | > and         | > Isolation \>  |                   |
|               | > circu       | > 15 Mohms,     |                   |
|               | it-to-circuit | > which is      |                   |
|               | > isolation.  | > improved from |                   |
|               |               | > Bard's        |                   |
|               |               | > previously    |                   |
|               |               | > marketed      |                   |
|               |               | > devices       |                   |
+---------------+---------------+-----------------+-------------------+
| > Circuit     | > Capacitance | > Capacitance   | > All samples     |
| > Capacitance | > evaluated   | > 175 pF, the   | > passed.         |
|               | > across all  | > capacitance   |                   |
|               | > (14)        | > for another   |                   |
|               | >             | > Bard device.  |                   |
|               |  combinations |                 |                   |
|               | > of          |                 |                   |
|               | > circuits.   |                 |                   |
+---------------+---------------+-----------------+-------------------+
| > Temperature | > Time        | > Ranges were   | > Three catheters |
| > Accuracy    |               | > given for the | > failed, but an  |
| > and Rise    |               | > resistance    | > explanation was |
| > Time        |               | > specs at 30   | > given. The      |
|               |               | > C, 60 C and   | > statistical     |
|               |               | > 95 C. Rise    | > calculations    |
|               |               | > time 0.8 sec. | > were re-run     |
|               |               |                 | > removing those  |
|               |               |                 | > values, and the |
|               |               |                 | > remaining       |
|               |               |                 | > catheters       |
|               |               |                 | > passed.         |
+---------------+---------------+-----------------+-------------------+
| > HF Current  | > Catheters   | > Leakage       | > All catheters   |
| > Leakage     | > subjected   | > current \<    | > passed, with a  |
|               | > to 24-hr    | > 8.17 mA/cm    | > worst-case      |
|               | > saline      | > per AAMI      | > reading of 4.1  |
|               | > soak.       | > HF-18,        | > mA/cm           |
|               | > Leakage     | > section       |                   |
|               | > current     | > 4.2.5.2       |                   |
|               | > measured    |                 |                   |
|               | > through     |                 |                   |
|               | > shaft while |                 |                   |
|               | > applying    |                 |                   |
|               | > 140V at 500 |                 |                   |
|               | > kHz to      |                 |                   |
|               | > electrodes  |                 |                   |
+---------------+---------------+-----------------+-------------------+
| > Catheter    | > Dynamic     | > No pass-fail  | > Impedance and   |
| > Impedance   | > impedance   | > criteria.     | > reactance       |
| > **(N=6)**   | > of catheter |                 | > measurements    |
|               | > measured    |                 | > consistent with |
|               | > while       |                 | > other products. |
|               | > applying    |                 |                   |
|               | > DC, 5 kHz,  |                 |                   |
|               | > or 500 kHz  |                 |                   |
|               | > voltages.   |                 |                   |
+---------------+---------------+-----------------+-------------------+
| > Catheter    | > Axial force | > Buckling      | > All devices     |
| > Buckle Test | > applied to  | > force         | > compared        |
|               | > distal tip  | > compared to   | > favorably to    |
|               | > and peak    | > another       | > the marketed    |
|               | > force       | > marketed      | > catheter, with  |
|               | > measured    | > catheter and  | > about half the  |
|               | > prior to    | > to peak       | > peak force      |
|               | > buckling.   | > forces        | > required to     |
|               |               | > required to   | > buckle (0.42    |
|               |               | > perforate the | > lbs vs. 0.77    |
|               |               | > pig           | > lbs). In        |
|               |               | > ventricular   | > addition, the   |
|               |               | > apex (1.2     | > peak force was  |
|               |               | > lbs) or       | > well below the  |
|               |               | > maximally     | > perforation     |
|               |               | > distend       | > force of the    |
|               |               | > (without      | > ventricular     |
|               |               | > perforation)  | > apex.           |
|               |               | > the r. atrial |                   |
|               |               | > appendage     |                   |
|               |               | > (0.46 lbs)    |                   |
+---------------+---------------+-----------------+-------------------+
| > Catheter    | > Count turns | > No specific   | > The devices     |
| > Torsion     | > to          | > pass-fail     | > compared        |
| > Test        | > electrical  | > criteria      | > favorably to    |
| > **(N=5)**   | > or          |                 | > another         |
|               | > mechanical  |                 | > marketed        |
|               | > failure     |                 | > product, with   |
|               | > while       |                 | > an average of   |
|               | > rotating    |                 | > 6.4 turns to    |
|               | > handle with |                 | > (mechanical)    |
|               | > fixed tip.  |                 | > failure. No     |
|               |               |                 | > electrical      |
|               |               |                 | > failures were   |
|               |               |                 | > noted.          |
+---------------+---------------+-----------------+-------------------+
| > Tip to      | > Measure the | > Tensile       | > All devices     |
| > Shaft       | > tensile     | > strength \>   | > passed, with an |
| > Tensile     | > force       | > 5.0 lbs.,     | > average tensile |
| > Test        | > required to | > based on      | > strength of     |
| > **(N=8)**   | > separate    | > tensile       | > 19.6 lbs.       |
|               | > the tip     | > strength of   |                   |
|               | > tubing from | > tip electrode |                   |
|               | > the shaft   | > adhered to    |                   |
|               | > tubing      | > cardiac       |                   |
|               |               | > tissue of 1.5 |                   |
|               |               | > lbs.          |                   |
+---------------+---------------+-----------------+-------------------+
| > Tip to      | > Measure the | > Tensile       | > All devices     |
| > Tip-stock   | > tensile     | > strength \>   | > passed, with an |
| > Tensile     | > force       | > 2.0 lbs.,     | > average tensile |
| > Test        | > required to | > with same     | > strength of     |
| > (**N=8)**   | > separate    | > justification | > 17.2 lbs.       |
|               | > the tip     | > as above.     |                   |
|               | > electrode   |                 |                   |
|               | > from the    |                 |                   |
|               | > tip tubing  |                 |                   |
+---------------+---------------+-----------------+-------------------+
| > Shaft to    | > Measure the | > Tensile       | > All devices     |
| > Handle      | > force       | > strength \>   | > passed, with an |
| > Tensile     | > required to | > 4.0 lbs.,     | > average tensile |
| > Test        | > separate    | > with the same | > strength of     |
| > **(N=13)**  | > the         | > justification | > 34.0 lbs.       |
|               | > catheter    | > as above.     |                   |
|               | > shaft from  |                 |                   |
|               | > the handle. |                 |                   |
+---------------+---------------+-----------------+-------------------+
| > Handle to   | > Measure the | > Tensile       | > All devices     |
| > Connector   | > force       | > strength \>   | > passed, with an |
| > Tensile     | > required to | > 4.0 lbs.,     | > average tensile |
| > Test        | > separate    | > based on the  | > strength of     |
| > **(N=13)**  | > the         | > tensile       | > 14.9 and 14.6   |
|               | > catheter    | > strength of   | > lbs. for the    |
|               | > extension   | > the LEMO      | > two joints      |
|               | > tubing from | > connector of  | > respectively.   |
|               | > the         | > 2.0 lbs.      |                   |
|               | > catheter    |                 |                   |
|               | > handle, or  |                 |                   |
|               | > from the    |                 |                   |
|               | > connector.  |                 |                   |
+---------------+---------------+-----------------+-------------------+

> Table 6. Bench Testing of Templink Extension Cable

+---------------+---------------+---------------+--------------------+
| **[Test       | ###### Method | ####### P     | #####              |
| Description]{ | s {#methods-1 | ass/Fail Crit | ### Results {#resu |
| .smallcaps}** |  .unnumbered} | eria {#passfa | lts-1 .unnumbered} |
|               |               | il-criteria-1 |                    |
|               |               |  .unnumbered} |                    |
+---------------+---------------+---------------+--------------------+
| > HF External | > Tested in   | > Leakage     | > The cable is     |
| > Leakage     | > compliance  | > current \<  | > capable of       |
| > Current     | > with IEC    | > 19.2 mA/cm  | > withstanding     |
| > (N=30)      | > 601-2-2     |               | > 150% of the      |
|               | > §19.101,    |               | > output of a      |
|               | > and HF-18   |               | > compatible       |
|               | > Annex C.    |               | > generator with   |
|               |               |               | > an average of    |
|               |               |               | > 1.58 mA/cm       |
|               |               |               | > leakage current. |
+---------------+---------------+---------------+--------------------+

## 9.2 Animal Testing  {#animal-testing .unnumbered}

Animal testing was performed in compliance with Good Laboratory
Practices (GLP) to fulfill the following objectives:

-   To establish adequate catheter mechanical performance, particularly
    steering and stiffness;

-   To assure temperature controlling ability using a compatible RF
    generator; and

-   To demonstrate adequate catheter performance in ablating atrial
    tissue.

Six healthy dogs were used to do four chronic and two acute studies. The
performance of the Stinger catheter was evaluated by creating lesions in
animals and collecting data on both acute and chronic safety and
effectiveness. To evaluate acute safety and effectiveness, eleven
lesions, in four places, were created in the four dogs with the Stinger
catheter between the coronary sinus and the AV node; between the
inferior vena cava and the AV node; at the tricuspid valve annulus; and
at the AV node. To evaluate chronic safety and effectiveness, the
Stinger catheter was used to deliver energy to nine sites in four dogs.

There were no instances of impedance rise or coagulum adherent to the
electrode as a result of energy delivery from the ablation system in any
of the dogs. The Stinger catheter was able to reach all of the selected
sites for ablation without difficulty, and energy was delivered with a
target temperature of 65 - 70°C. AV block was successfully created in
the dogs in the acute study indicating catheter efficacy for AV nodal
ablation. The acute lesion dimensions were similar to those found in the
published literature and to those created with another marketed catheter
system.

# Clinical Investigations

The Stinger™ Ablation catheter and the related accessory devices were
evaluated in a clinical study with the EPT-1000 TC RF generator and
another investigational RF generator, for the treatment of
supraventricular tachycardias (SVT).

## 10.1 Study Design {#study-design .unnumbered}

The Stinger™ Ablation catheter was evaluated in a prospective,
multi-center trial. Acute success was defined as the proportion of
patients where treatment with the study device was able to: 1) eliminate
the functioning of aberrant pathways in patients with symptomatic SVT
caused by accessory pathways, 2) eliminate the functioning of aberrant
pathways in patients with symptomatic SVT caused by AVNRT, 3) ablate the
AV node for control of a rapid ventricular response in patients with
symptomatic, drug resistant tachycardias. Chronic success (Freedom from
recurrence of arrhythmia) was defined as the proportion of acute success
patients, who, at a minimum of 3 months post ablation, continue to
have: 1) an absence of symptoms related to the index arrhythmia; or 2)
effective AV block.

## 10.2 Patients Studied {#patients-studied .unnumbered}

Patients Enrolled in Study 251

Patients Discontinued Prior to Study 4

\- target arrhythmia non-inducible 3

\- target arrhythmia non indicated 1

Patients Treated in Study 247

## 10.3 Demographics  {#demographics .unnumbered}

Patient Demographics for the study are shown in Table 7 below. The
number of arrhythmia types treated and the percentage of patients with
these arrhythmias are shown in Table 8 below.

**Table 7. Patient Demographics**

**Population: All Patients with Treatment Attempted**

#### N=247 \[Males 68% (167) / Females 32% (80)\] {#n247-males-68-167-females-32-80 .unnumbered}

+-----------------------+-----+-----+-----+--------+---------+-------+
|                       | **  | **  | **S | **Min  | **Ma    | **Med |
|                       | N** | Mea | td. | imum** | ximum** | ian** |
|                       |     | n** | De  |        |         |       |
|                       |     |     | v** |        |         |       |
+-----------------------+-----+-----+-----+--------+---------+-------+
| Age (years)           | 247 | 5   | 1   | 18.0   | 90.0    | 50.0  |
|                       |     | 1.3 | 5.9 |        |         |       |
+-----------------------+-----+-----+-----+--------+---------+-------+
| Duration of SVT       | 244 | 1   | 1   | 0.0    | 69.9    | 9.6   |
| Symptoms (years)      |     | 3.6 | 3.6 |        |         |       |
+-----------------------+-----+-----+-----+--------+---------+-------+
| Frequency of SVT      | 224 | 9   | 23  | 0.1    | 1826.3  | 12.0  |
| Symptoms (times/year) |     | 9.6 | 8.4 |        |         |       |
+-----------------------+-----+-----+-----+--------+---------+-------+
| No. of SVT Episodes   | 212 | 2   | 7   | 0.0    | 600.0   | 6.0   |
|                       |     | 8.1 | 6.7 |        |         |       |
| (in Last 6 months)    |     |     |     |        |         |       |
+-----------------------+-----+-----+-----+--------+---------+-------+
| No. of Hospital       | 247 | 1.1 | 1.3 | 0.0    | 8.0     | 1.0   |
| Visits                |     |     |     |        |         |       |
|                       |     |     |     |        |         |       |
| (in Last 6 months)    |     |     |     |        |         |       |
+-----------------------+-----+-----+-----+--------+---------+-------+

#### Table 8. Number of Arrhythmia Types Treated {#table-8.-number-of-arrhythmia-types-treated .unnumbered}

+------------------------------------+-------------------+-------------+
|                                    | Percent of        | Number of   |
|                                    | Patients          |             |
|                                    |                   | Arrhythmias |
|                                    | N=247             |             |
|                                    |                   | N=251       |
+------------------------------------+-------------------+-------------+
| Accessory Pathway - Concealed      | 10%               | 25          |
+------------------------------------+-------------------+-------------+
| Accessory Pathway - Non-concealed  | 10%               | 25          |
+------------------------------------+-------------------+-------------+
| Accessory Pathway - both types     | 1%                | 3           |
+------------------------------------+-------------------+-------------+
| AVNRT                              | 66%               | 163         |
+------------------------------------+-------------------+-------------+
| AV Node Ablation for Rate Control  | 14%               | 35          |
+------------------------------------+-------------------+-------------+

Note: 4 patients had both an Accessory Pathway and AVNRT treated.

## 10.4 Procedure Data  {#procedure-data .unnumbered}

For most of the procedures (99%, 240/242 patients), energy was delivered
using the constant temperature mode. Catheters were most often exchanged
due to needing a different catheter curve (63%, 41/65 energy
deliveries). The reason for terminating the energy delivery was usually
based on the desired time interval being achieved (56%, 882/1588).
Additional information on the energy delivery is shown in Table 9 below.

Table 9. Parameters of Energy Delivery

  ------------------------------------------------------ ----------------
  mean number of energy applications per patient         6.5 ± 6.2

  mean duration per application (seconds)                43.3 ± 29.2

  mean duration for all of the energy applications in a  283.4 ± 280.2
  single procedure (seconds)                             

  temperature setting (C)                                61.2 ± 5.2°C

  actual delivered temperature (C)                       55.7 ± 7.2°C.

  mean ablation (procedure) time (minutes)               63.2 ± 62.5

  mean fluoroscopy time (minutes)                        24.4 ± 22.1
  ------------------------------------------------------ ----------------

## 10.5 Acute and Chronic Effectiveness  {#acute-and-chronic-effectiveness .unnumbered}

As shown in Table 10 below, of the 247 patients treated with the
Stinger™ Ablation Catheter, acute success was achieved in 230 patients
(93%). There were a total of 17 acute failures of which 12 procedures
were completed with a non-protocol device, no energy was delivered in 4
procedures due to RF generator malfunction, and the study device was not
used in 1 patient due to the patient's tortuous anatomy.

#### Table 10. Success Results for Specific Arrhythmias {#table-10.-success-results-for-specific-arrhythmias .unnumbered}

+-----------------------+-----------------------+-----------------------+
|                       | ####                  | **Freedom from        |
|                       | Acute Success {#acute | Recurrence of\        |
|                       | -success .unnumbered} | Arrhythmia at 3       |
|                       |                       | months for Patients   |
|                       |                       | Successfully Treated  |
|                       |                       | (Chronic Success)**   |
+-----------------------+-----------------------+-----------------------+
| **Accessory**         | 88%                   | 93%                   |
|                       |                       |                       |
| **Pathway**           | 43/49                 | 38/41                 |
+-----------------------+-----------------------+-----------------------+
| **AVNRT**             | 95%                   | 97%                   |
|                       |                       |                       |
|                       | 151/159               | 146/150               |
+-----------------------+-----------------------+-----------------------+
| **AV**                | 91%                   | 100%                  |
|                       |                       |                       |
| **node**              | 32/35                 | 31/31                 |
+-----------------------+-----------------------+-----------------------+
| **\>1 Type**          | 100%                  | 100%                  |
|                       |                       |                       |
|                       | 4/4                   | 4/4                   |
+-----------------------+-----------------------+-----------------------+
| **Total \***          | 93%                   | 97%                   |
|                       |                       |                       |
|                       | 230/247               | 219/226\*\*           |
|                       |                       |                       |
|                       | CI: \[89%, 96%\]      | CI: \[95%, 99%\]      |
+-----------------------+-----------------------+-----------------------+

\* Exact 95% confidence intervals (CI) based on the binominal
distribution

\*\* Four (4) patients not evaluated for chronic success due to 1 death
and 3 lost-to-follow-up prior to 3 months.

[Antiarrhythmic Medications]{.underline}: For this study, a medication
was considered antiarrhythmic if it was given specifically for treatment
of the patient's arrhythmia. The percentage of patients receiving
antiarrhythmia medications before and after the ablation are shown in
Table 11 below.

**Table 11. Antiarrhythmic Medications**

  ----------------------- ----------------------- -----------------------
                          \% of Patients Prior to \% of Patients at 3
                          Ablation                Months

  All                     68% (156/230)           11% (25/226)

  Accessory Pathways      53% (23/43)             5% (2/41)

  AVNRT                   68% (102/151)           7% (11/150)

  AV Node                 88% (28/32)             39% (12/31)

  \>1Type                 5% (3/4)                0% (0/4)
  ----------------------- ----------------------- -----------------------

## 10.6 Observed Adverse Events {#observed-adverse-events .unnumbered}

A summary of the major and minor adverse events and patient deaths
observed in this study were listed in section 8.0 above. A total of 37
minor procedural adverse events (as summarized in Table 12 below) were
reported for 29 patients:

**Table 12. Procedural Adverse Events**

Population: All Patients Enrolled (N=251)

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

**Number of Occurrences**

**\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_**

Abnormal ECG 1

Abnormal Vision 1

Application Site Reaction 1

Asthenia 1

Back Pain 1

> Bundle Branch Block 1

Chest Pain 6

> Dizziness 1
>
> Ecchymosis 1
>
> Fever 2

Injection Site Pain, Hemorrhage or Mass 8

Nausea (with or without vomiting) 3

Neck Pain 1

Pain 1

Syncope (vasovagal) 7

Ventricular Arrhythmia 1

> \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
>
> Total: 37

# Safety and effectiveness data for the treatment of cardiac arrhythmias with similar RF ablation catheters

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^1-3^, especially when the lesions are
created with a "conventional" RF ablation catheter. The FDA considers
"conventional" RF ablation catheters to have the following
characteristics:

-   Create endocardial lesions

```{=html}
<!-- -->
```
-   Single 4-5 mm ablation electrode

-   Temperature sensing capability

-   Not irrigated or cooled

-   "Steerable" (i.e., catheter has a manually-deflectable tip)

-   Placed percutaneously

-   Designed to deliver a maximum of 50W RF power to the endocardium

The FDA considers the Stinger™ Ablation Catheter to be a "conventional"
RF ablation catheter.

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 studied in the clinical trial of the
Stinger™ Ablation Catheter. Table 13 show data pooled from the medical
literature on three arrhythmias treated with cardiac ablation.
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.

###### Table 13: Safety and Effectiveness of RF Ablation Using Conventional RF Ablation Catheters {#table-13-safety-and-effectiveness-of-rf-ablation-using-conventional-rf-ablation-catheters .unnumbered}

+--------------+----+---------+----------+----------+----------------+
| Arrhythmia   | N  | Acute   | Chronic  | Compl    | Comments       |
|              |    | Success | Success  | ications |                |
+--------------+----+---------+----------+----------+----------------+
| Atrial       | 14 | 72 -    | 85-100%  | 0 - 6%   | Linear lesions |
| Flutter^4,9- | 37 | 100%    |          |          |                |
| 11,13,14,16^ |    |         |          |          | across isthmus |
+--------------+----+---------+----------+----------+----------------+
| Ventricular  | 14 | 66 -    | 86%      | 2 - 8%   | Right and left |
| Tachycardia  | 63 | 85%     |          |          | ventricles     |
| ^13,14,16^   |    |         |          |          |                |
+--------------+----+---------+----------+----------+----------------+
| Atrial       | 4  | 91%     | 85%      | 3%       | Right and left |
| Tachy        | 94 |         |          |          | atria          |
| cardia^7,16^ |    |         |          |          |                |
+--------------+----+---------+----------+----------+----------------+

## American College of Cardiology/ American Heart Association Guidelines {#american-college-of-cardiology-american-heart-association-guidelines .unnumbered}

Under the American College of Cardiology/American Heart Association
(ACC/AHA) Guidelines for Clinical Electrophysiological and Catheter
Ablation Procedures,^15^ 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.

## Summary of data from the medical literature  {#summary-of-data-from-the-medical-literature .unnumbered}

The combination of published safety and effectiveness data and the
published ACC/AHA guidelines for clinical use support a broader
arrhythmia indication than the specific arrhythmias treated in the
clinical study of the Stinger™ Ablation catheter.

# Conclusions Drawn from Studies and from data in the medical literature

The preclinical testing demonstrates that the catheter should maintain
its mechanical and electrical integrity and that the patient-contacting
materials should be biocompatible, under the proposed conditions of use.
The animal testing established the adequate performance of the device in
terms of its maneuverability and lesion creation. The data collected in
the clinical study, as well as data from the medical literature, provide
reasonable assurance that the Stinger Ablation System is safe and
effective for the stated indications, under the proposed conditions of
use.

# Panel Recommendation

Pursuant to the provisions of section 515(c)(2) of the Food, Drug, and
Cosmetic Act (FD&C) as amended by the Safe Medical Devices Act of 1990
(SMDA 1990), this PMA application was not referred to the Circulatory
System Devices Panel, an FDA advisory panel committee, for review and
recommendation because the information in the PMA substantially
duplicates information previously reviewed by this panel.

# FDA Decision

FDA determined that the device is reasonably safe and effective when
used as indicated in the labeling. CDRH issued an approval order for the
applicant's PMA, P000020, on November 29, 2000.

# Approval Specifications

**Directions for Use:** See Final Draft Labeling (Information for Use)

**Hazards to Health from Use of the Device**: See **INDICATIONS,
CONTRAINDICATIONS, WARNINGS AND PRECAUTIONS,** and **ADVERSE EVENTS** in
the final draft labeling (Information for Use).

**Post-approval Requirements and Restrictions**: See Approval Order

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2.  Langberg JJ, et al. Radiofrequency catheter ablation: The effect of
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4.  Kay GN, Epstein AE, Dailey SM, Plumb VJ. Role of RF ablation in the
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10. Fisher B, et al. Radiofrequency catheter ablation of common atrial
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12. Ganz LI, Stevenson WG. Catheter mapping and ablation of ventricular
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