1. Catheter Features
Catheter Characteristics and Clinical Requirements

2. Introduction What are the major features of an ablation catheter?
handle
proximal shaft
distal shaft, including curves and steering mechanism
tip electrode
What are the differences between a Blazer II, Blazer XP, and CHILLI II ablation catheter?
The difference is in the TIP ELECTRODE
The difference is in THERAPY APPLICATION
Blazer II = AVNRT
Blazer XP = Flutter
Chilli II = AFib

3. Preparing a Catheter Presentation
Ask yourself the following four important questions:
What is the pathology the clinician is treating?
i.e. AVNRT, A Flutter, A Fib, etc.
What does the physician need from a catheter in order to treat this pathology?
i.e lesion characteristics, anatomical considerations, etc.
What BSC catheter features resolve the clinical needs?
i.e. curve reach, tip electrode size, etc.
How do you plan on demonstrating these characteristics?
The following presentation focuses on how to demonstrate feature by feature.
You need to select the appropriate set of features you wish to present to the physician.

4. Catheter Features Distal Segment Length & Curve Shape Performance
Active Steering
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Tip Electrode
Tip Size
Cooling
Temperature Sensor
Proximal Shaft
Torqueability
Pushability
Trackability

5. Tip Electrode Size
Available in 7f /4mm and 8f /8mm sizes. Increasing the size of the tip electrode allows more RF power to be delivered into the tissue thus increasing the volume of the lesion.
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Distal Segment
Length & Curve Shape
Performance
Active Steering
Tip Electrode
Tip Size
Cooling
Temperature Sensor

6. Tip Electrode Size Blazer II™, Blazer II XP™ , Chilli II™
Tip Electrode XP:
8f/8mm; 8f/10mm
Provides electrograms for evaluation of timing
Greater surface area allows more power to be delivered and creates larger volume lesions for Flutter
8f/8mm VM – conforms more easily to undulating surfaces such as the TV annulus
Tip Electrode Cooled:
7F/4MM
Provides sharp electrograms for evaluation of timing and morphhology of signals.
Minimized thrombus/charring & deep lesions
Tip Electrode STD:
7F/4MM
Provides sharp electrograms for evaluation of timing and morphhology of signals.
Conventional size lesions for SVTs
7f/4mm tip electrodes are a compromise of efficient ablation and effective electrical signal information. The 8f/8mm tip on the other hand is a compromise between maneuverability and lesion depth/volume. In short, the larger the tip electrode surface area in contact with the tissue, the greater power that can be introduced into the tissue and therefore, the greater the lesion volume. Cooling, discussed in the next section, plays an additive role in lesion volume creation by extracting heat from the lesion thus allowing for even more power to be introduced into the tissue and therefore creating a greater volume lesion.

7. Cooling
PASSIVE COOLING is the conduction of heat from the tip electrode to the blood flowing around it. ACTIVE COOLING is the conduction of heat from the tip electrode to an injected sterile cooling fluid which passes through the tip .
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Tip Electrode
Tip Size
Cooling
Temperature Sensor
Distal Segment
Length & Curve Shape
Performance
Active Steering
The flow of blood across the exposed surface of the tip electrode extracts heat from its surface and is called passive cooling. By injecting sterile fluid into the tip electrode, additional heat is extracted and is called active cooling. The amount of heat extraction is dependent on the flow of the fluid (blood or cooling), the initial temperature of the fluid, and the tip electrode surface area in contact with the cooling fluid (blood or cooling).

8. PASSIVE Cooling Blazer II™, Blazer II XP™
Conductive Cooling via Blood Flow (37degC)
Heat conducted from
warm electrode into
cooler blood
Heat conducted from
warm tissue into
cooler blood
Electrode
heats up
Blood
Tissue
Ohmic heated tissue conducts heat into cooler electrode and surrounding tissues
HOT Tissue
(Lesion)

9. ACTIVE Cooling Chilli II™
Conductive Cooling via Blood Flow (37degC)
Cooling fluid
Takes heat OUT
of electrode
Heat conducted from
warm electrode into
cooler blood
Heat conducted from
warm tissue into
cooler blood
Electrode
heats up
Blood
Tissue
Ohmic heated tissue conducts heat into cooler electrode and surrounding tissues
HOT Tissue
(Lesion)

10. Temperature Sensor
Temperature sensors are either Thermistor or Thermocouple and imbedded or exposed. For RF cardiac ablation the location (imbedded or exposed) rather than the type of temperature sensor effects the value of the temperature measured.
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Tip Electrode
Tip Size
Passive/Active Cooling
Temperature Sensor
Distal Segment
Length & Curve Shape
Performance
Active Steering
Two types of temperature sensors – Thermistor or Thermocouple. For the purpose of ablation, there is no discernable difference in temperature accuracy. The location of the sensor, exposed or imbedded, depends on the catheter family and effects the quality of the temperature information. The following are the locations of the temperature measured and its value:
Under the endocardium 1 – 3 mmm Optimal location because this is the hottest spot of the tissue and by knowing this can avoid popping.
Surface of the endocardium --- Optimal to reduce thrombus and charring
Tip electrode exposed --- average temperature of tip electrode and tissue/blood contact, up to 20ºC difference between tissue and measured temperature
Tip electrode imbedded --- average temperature of tip electrode, up to 30ºC difference between tissue and measured temperature
Active Cooled Tip electrode imbedded --- average temperature of tip electrde and cooling fluid, up to 50ºC difference between tissue and measured temperature.

11. Temperature Sensor Blazer II™ and Blazer II XP™
CHARACTERISTICS
Thermistor Exposed
Blood or Tissue Exposed
Average Temperature
Tip
Blood or Tissue

12. Temperature Sensor Chilli II™
CHARACTERISTICS
Thermocouple Embedded
Cooling Fluid Exposed
Average temperature
Tip
Cooling Fluid

13. Distal Length and Curve Shape
Distal tubings come in various length and curve shape configurations to facilitate the access to various regions of the heart.
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Tip Electrode
Tip Size
Cooling
Temperature Sensor
Distal Segment
Length & Curve Shape
Performance
Active Steering
Distal tubings come in standard, medium and extended configurations and are offered with small, standard, large, and asymetric curves. The tubing configurations and curve shapes vary by family and whether the tubing material is standard or high torque

14. Distal Length and Curve Shape Blazer II™
Tight Crevices or
Small Hearts
All-purpose
Average Hearts
Long Reach
Large Hearts
Unknown Arrhythimia
Unusual Anatomy
Tubing Lengths
Standard:
Multipurpose offers the best combination of stability, reach and maneuverability.
Medium:
For left sided retrograde access, tortuous anatomy, or need to maneuver catheter around chamber to access ablation site.
Extended:
For older patients with much fibrosis; minimally traumatic distal. =
HTD Distal

15. Distal Length and Curve Shape Blazer II XP™
All-purpose VT
Long Reach
Right
A Flutter
Unusual Anatomy
Tubing Lengths
Standard:
Multipurpose offers the best combination of stability, reach and maneuverability.
Medium:
For left sided retrograde access, tortuous anatomy, or need to maneuver catheter around chamber to access ablation site.

16. Distal Length and Curve Shape Chilli II™
All-purpose or
Average Hearts
Trackable
For
Large Hearts and Sheaths
Unusual Anatomy
Tubing Lengths
Standard:
Multipurpose offers the best combination of stability, reach and maneuverability.

17. Distal Performance
Distal tubing materials are designed either to minimize vascular/endocardial trauma or to maximize tip contact /manueverability. Ring electrode spacing is designed to maximize the quality of electrical signal information.
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Tip Electrode
Tip Size
Cooling
Temperature Sensor
Distal Segment
Length & Curve Shape
Performance
Active Steering

18. Distal Performance Distal Tubing Firmness: Distal Tubing Firmness
High Torque
Pebax 40 – light grey segment color
High performance optimizes the torque transfer from proximal shaft to tip electrode (ie lateral contact force)
Ring Spacing:
Quad 2.5 mm
provides sharp electrograms for evaluation of timing and morphology of signals.
Distal Tubing Firmness
Standard torque
Pallethane 35 – light blue segment color
Less traumatic for patients with thin or fibrotic vasculature and/or endocardium
Ring Spacing:
Quad 2.5 mm
provides sharp electrograms for evaluation of timing and morphology of signals.
Cardiac contractions and respiratory cycles can easily displace the catheter tip from the target site. Lateral contact force, i.e., the force perpendicular to the steering plane, is needed to overcome these physiological movements.
The combination of steering coil, shaft braid, and catheter shaft provide the torque characteristics to transfer the force from rotation of the handle to the tip, providing the lateral contact force to stabilize the catheter tip, even when the target site is not in the steering plane of the catheter.

19. Active Steering
Pull wires are attached to opposite sides of a steering plate and allow precise control of curve formation. ACTIVE STEERING is the ability of the tip electrode to press against the tissue either into or away from the direction of curvature.
Distal Segment
Length & Curve Shape
Performance
Active Steering
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Tip Electrode
Tip Size
Cooling
Temperature Sensor
The Blazer™ Catheter uses a steering plate (aka spring steel plate) for precise curve formation. There are 2 pull wires, one for each curve, used. These wires attach to each side of the steering plate and are actuated by the handle bi-wing steering lever. As the steering lever is rotated through its range of motion, the guidewire pulls the steering plate in one direction or the other, curving the tip to the desired degree. Two characteristics of this steering is ACITVE and BIDIRECTIONAL STEERING. ACTIVE STEERING is the ability of the tip electrode to press against the tissue either into or away from the direction of curvature. BIDIRECTIONAL STEERING is the ability for the catheter to form a curve in one direction and duplicate this curvature without having to rotate the catheter 180º.
Proximal Shaft
Torqueability
Pushability
Trackability

20. Into and Away from Curvature
Active Steering
Bi-Directional
Into and Away from Curvature

21. Torqueability
The steering coil and woven metal braid efficiently transfer rotation of the catheter handle to the tip for predictable movement, reducing twist or “whip”
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Tip Electrode
Tip Size
Cooling
Temperature Sensor
Distal Segment
Length & Curve Shape
Performance
Active Steering
“Torque” is a turning or twisting force. To steer the catheter tip predictably, rotation of the catheter handle (torque of the handle) must be reflected in a rotation of the catheter tip. Ideally, this would be a 1:1 relationship, where a defined rotation of the handle results in the same rotation of the catheter tip.
Excess handle rotation is difficult to accomplish and still maintain catheter position. Also, torque build-up between the handle and tip is stored in the catheter shaft, which can result in abrupt and sudden movement of the tip, called “whip”. The steering coil, metal braid, shaft polymer, and shaft/tip transition all contribute to efficient torque transfer from handle to tip. This minimizes handle rotation and allows predictable tip steering.
Ablation procedures for complex arrhythmias may last for several hours. The Rx catheter must maintain its properties and handling characteristics over extended periods of time in a saline fluid environment, i.e., blood at 37 degrees C. The polymer shaft is resistant to swelling in this environment that will soften the catheter shaft with subsequent loss of catheter support and degradation of performance

22. Pushability
The woven metal braid around the catheter shaft provides the flexibility to allow the catheter shaft to follow the tip as it is advanced into position and to follow through tortuous vasculature
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Tip Electrode
Tip Size
Cooling
Temperature Sensor
Distal Segment
Length & Curve Shape
Performance
Active Steering
To access target sites, the catheter often needs to transverse tortuous vasculature and change directions at acute angles. “Trackability” defines the degree to which a catheter may be advanced through the sheath and the vascular system without blocking, kinking, or bending so as to prevent or inhibit forward motion.
The woven metal braid provides a flexible support from handle to tip that provides the necessary flexibility for the catheter shaft to follow the tip, without kinking, as it is steered into position.
Ablation procedures for complex arrhythmias may last for several hours. The Rx catheter must maintain its properties and handling characteristics over extended periods of time in a saline fluid environment, i.e., blood at 37 degrees C. The polymer shaft is resistant to swelling in this environment that will soften the catheter shaft with subsequent loss of catheter support and degradation of performance

23. Trackability
The woven metal braid around the catheter shaft provides the flexibility to allow the catheter shaft to follow the tip as it is advanced into position and to follow through tortuous vasculature
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Tip Electrode
Tip Size
Cooling
Temperature Sensor
Distal Segment
Length & Curve Shape
Performance
Active Steering
To access target sites, the catheter often needs to transverse tortuous vasculature and change directions at acute angles. “Trackability” defines the degree to which a catheter may be advanced through the sheath and the vascular system without blocking, kinking, or bending so as to prevent or inhibit forward motion.
The woven metal braid provides a flexible support from handle to tip that provides the necessary flexibility for the catheter shaft to follow the tip, without kinking, as it is steered into position.
Ablation procedures for complex arrhythmias may last for several hours. The Rx catheter must maintain its properties and handling characteristics over extended periods of time in a saline fluid environment, i.e., blood at 37 degrees C. The polymer shaft is resistant to swelling in this environment that will soften the catheter shaft with subsequent loss of catheter support and degradation of performance

24. Torqueability, Pushability & Trackability
Tubing Firmness
High Torque Proximal Shaft:
balances flexibility, torqueability and pushability
allowis the proximal shaft to follow the path of distal tip electrode while maximizing its contact during ablation.
Inner Core Construction
Steering Coil:
minimizes buckling of proximal shaft during curve acutation
increasing the maneuverability and tip electrode contact of the catheter.

25. Tension Control
The tension control allows the physician to decide the amount of resistance or tension on the steering mechanism. Low tension maximizes the tactile response while high tension allows for hands-free curve retention.
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Tip Electrode
Tip Size
Cooling
Temperature Sensor
Distal Segment
Length & Curve Shape
Performance
Active Steering
It is important to recognize tissue resistance to the catheter tip movement. Too much resistance can indicate that further advancement of the tip could lead to tissue perforation. Too little resistance can indicate that the catheter tip is not in solid contact with tissue and ablation will not be efficient.
The combination of steering coil and shaft braid transfers tissue resistance efficiently from tip to steering lever, providing excellent tactile sensitivity during steering and placement of the tip to the user.

26. Tension Control + = Add More Friction - = Release Friction
Tension Control (Unlock & Lock) – restrains steering mechanism allowing hand- free curve retention and providing added security against tip contact slippage.
+ = Add More Friction
- = Release Friction

27. Bi Wing Steering
Designed for maximum comfort while allowing fine micro movements and control with minimal effort. The Bi wing Steering wheel is also in plane with the distal catheter curve
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Tip Electrode
Tip Size
Cooling
Temperature Sensor
Distal Segment
Length & Curve Shape
Performance
Active Steering
Two fingers are better than one thumb. Steering with two fingers provides additional tactile sensory information as well as levergare to facilitate microcmovementes. In conjunction with the steering cam design, whcih allows very smooth actuation from one side to the other without “dead” space or jumpiness.

28. THUMB always points in the direction of the curvature
Bi Wing Steering
Tension Control (Unlock & Lock) – restrains steering mechanism allowing hand- free curve retention and providing added security against tip contact slippage.
THUMB always points in the direction of the curvature

29. Handle Ergonomics
The handle is designed for comfort as well as to provide tactile sensory information about the actuation of the catheter.
Handle
Tension Control
Bi-wing Steering
Handle Ergonomics
Proximal Shaft
Torqueability
Pushability
Trackability
Tip Electrode
Tip Size
Cooling
Temperature Sensor
Distal Segment
Length & Curve Shape
Performance
Active Steering
The handle fits large as well as small hands. The length is sufficient to provide support during long procedures.

30. Handle Ergonomics Flats on the handle
Tension Control (Unlock & Lock) – restrains steering mechanism allowing hand- free curve retention and providing added security against tip contact slippage.
Flats on the handle
Align with plane of distal curvature
Rest for palm during long cases
Labeling type of catheter

31. EPT-10511_02/06 D. McGee
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