Medtronic 693152 Technical Manual

SPRINT FIDELIS™ 6931

A09204001A_view.pdf

Steroid eluting, tripolar, screw-in, ventricular lead with
RV defibrillation coil electrode

Technical manual

Caution: Federal Law (USA) restricts this
device to sale by or on the order of a
physician (or properly licensed
practitioner).

The following are trademarks of Medtronic: Medtronic, Sprint
Fidelis, Sprint Quattro Secure, Quick Twist

Table of contents

Device description 5

Contents of package 6
Accessory descriptions 6

Indications 6

Contraindications 7

Warnings and precautions 7

Potential adverse events 10

Clinical study 11

Model 6947 clinical study 11
Model 6932 (single-coil) clinical study 14
Additional performance measurements with active can ICDs 16

Directions for use 16

Opening the package 16
Verifying the mechanical functioning of the helix electrode 17
Inserting the lead 19
Positioning the lead 20
Securing the helix electrode into the endocardium 21
Taking electrical measurements and defibrillation efficacy
measurements 23
Anchoring the lead 24
Connecting the lead 25
Placing the device and leads into the pocket 25
Post-implant evaluation 26

Detailed device description 27

Specifications (nominal) 27
Specifications drawing (nominal) 28

Medtronic warranty 29

Service 29

6931 Technical Manual 3

Device description

The Medtronic Sprint Fidelis Model 6931 lead is a steroid eluting,
tripolar, screw-in, ventricular lead with a right ventricular (RV)
defibrillation coil electrode. The lead is designed for pacing, sensing,
cardioversion, and defibrillation therapies.

The lead features an extendable/retractable helix electrode, silicone
insulation with overlay, parallel conductors, titanium nitride coated
platinum iridium tip and ring electrodes, and a RV coil electrode. See
“Specifications drawing (nominal)” on page 28 for a lead drawing.

■

The helix electrode is common to the connector pin of the

1

bipolar leg.

IS-1

■

The ring electrode is common to the connector ring of the
IS-1 bipolar leg.

■

The RV coil electrode is common to the DF-12 leg of the
bifurcation, labeled and marked with a red band.

The RV coil delivers cardioversion and defibrillation therapies. Pacing
and sensing occur between the helix and ring electrodes.

The IS-1 bipolar leg of the bifurcation features a lumen for stylet
passage. The DF-1 connector legs will not accept a stylet.

The helix electrode can be actively fixed into the endocardium. The
helix electrode can be extended or retracted by rotating the IS-1
connector pin with either the Quick Twist tool assembled on the lead
or the white fixation tool.

The distal tip contains a maximum of 1.0 mg of dexamethasone
acetate. Exposure to body fluids elutes the steroid from the lead tip.
The steroid is known to suppress the inflammatory response that is
believed to cause threshold rises typically associated with implanted
pacing electrodes.

1

IS-1 refers to the International Connector Standard (ISO 5841-3) whereby
pulse generators and leads so designated are assured of a basic
mechanical fit.

2

DF-1 refers to the International Connector Standard (ISO 11318) whereby
pulse generators and leads so designated are assured of a basic
mechanical fit.

6931 Technical Manual 5

Contents of package

The lead and accessories are provided sterile. Each package
contains the following:

■

1 lead with 1 radiopaque anchoring sleeve1, stylet, and Quick
Twist tool

■

1 vein lifter

■

1 slit anchoring sleeve

■

1 white fixation tool

■

2 pin caps

■

extra stylets

■

product literature

Accessory descriptions

Stylet – A stylet provides additional stiffness and controlled flexibility

for maneuvering the lead into position. Each stylet knob is labeled
with the stylet diameter and length.

Anchoring sleeve – An anchoring sleeve secures the lead from
moving and protects the lead insulation and conductors from damage
caused by tight sutures.

Slit anchoring sleeve – A slit anchoring sleeve secures excess lead
length in the device pocket.

Pin cap – A pin cap covers and insulates unused connector pins.

Vein lifter – A vein lifter facilitates lead insertion into a vessel.

White fixation tool – The white fixation tool facilitates connector

pin rotation.

Quick Twist tool – The Quick Twist tool facilitates both connector pin
rotation and stylet insertion into the lead. This tool comes assembled
on the lead.

Indications

The lead is intended for single, long-term use in the right ventricle.

This lead has application for patients for whom implantable
cardioverter defibrillators are indicated.

1

Two radiopaque anchoring sleeves are provided with leads 85 cm or longer.

6 6931 Technical Manual

Contraindications

Atrial use – The lead is contraindicated for the sole use of detection

and treatment of atrial arrhythmias.

Ventricular use – The lead is contraindicated for ventricular use in
patients with tricuspid valvular disease or a tricuspid mechanical
heart valve.

Transient ventricular tachyarrhythmias – The lead is
contraindicated for patients with transient ventricular
tachyarrhythmias due to reversible causes (drug intoxication,
electrolyte imbalance, sepsis, hypoxia) or other factors (myocardial
infarction, electric shock).

Steroid use – The lead is contraindicated in patients for whom a
single dose of 1.0 mg of dexamethasone acetate may
be contraindicated.

Warnings and precautions

For single use only – Do not resterilize and reimplant an

explanted lead.

Inspecting the sterile package – Inspect the package prior
to opening.

■

If the seal or package is damaged, contact your local
Medtronic representative.

■

Do not use the product after its expiration date.

Ethylene oxide resterilization – The lead has been sterilized with
ethylene oxide prior to shipment. If the integrity of the sterile package
has been compromised prior to the expiration date, resterilize using
ethylene oxide. Avoid resterilization techniques that could damage
the lead.

■

Refer to sterilizer instructions for operating instructions.

■

Use an acceptable method for determining sterilizer
effectiveness, such as biological indicators.

■

Do not exceed temperatures of 55°C (131°F).

■

Do not resterilize more than 1 time.

■

After resterilization, allow the device to aerate ethylene
oxide residues.

Electrophysiologic testing – Prior to lead implant, it is strongly
recommended that patients undergo a complete cardiac evaluation,
which should include electrophysiologic testing. Also,
electrophysiologic evaluation and testing of the safety and efficacy of
the proposed pacing, cardioversion, or defibrillation therapies are
recommended during and after the implant of the system.

6931 Technical Manual 7

Steroid use – It has not been determined whether the warnings,
precautions, or complications usually associated with injectable
dexamethasone acetate apply to the use of this highly localized,
controlled-release device. For listing of potentially adverse effects,
refer to the Physician’s Desk Reference.

Steroid tip – Reducing the available amount of steroid may
adversely affect low-threshold performance. Avoid reducing the
amount of steroid available prior to lead implant.

■

Do not allow the electrode surface to come in contact with
surface contaminants.

■

Do not wipe or immerse the electrode in fluid, except blood, at
the time of implant.

Handling the lead – Handle the lead with great care at all times.

■

Protect the lead from materials shedding particles such as lint
and dust. Lead insulators attract these particles.

■

Handle the lead with sterile surgical gloves that have been
rinsed in sterile water or a comparable substance.

■

Do not severely bend, kink, or stretch the lead.

■

Do not use surgical instruments to grasp the lead or
connector pins.

■

Do not immerse leads in mineral oil, silicone oil, or any other
liquid, except blood, at the time of implant.

■

Do not implant the lead without first verifying the mechanical
functioning of the helix electrode. Refer to the section “Verifying
the mechanical functioning of the helix electrode” on page 17,
for complete instructions.

■

Do not exceed the recommended maximum number of
rotations to extend or retract the helix electrode. Exceeding the
maximum number may result in fracture or distortion of the
inner conductor or helix electrode. The number of rotations
required to fully extend or retract the helix electrode is variable;
refer to the section “Specifications (nominal)” on page 27, for
the recommended maximum number of rotations.

■

Inserting the lead using a lead introducer that features a
hemostasis valve may require a larger introducer than the size
recommended. To avoid distortion of the coil electrode, do not
withdraw the lead through a hemostasis valve.

Handling the stylets – Use care when handling stylets.

■

Do not use excessive force or surgical instruments when
inserting a stylet.

■

Avoid overbending and kinking.

■

Use a new stylet when blood or other fluids accumulate on the
stylet. Accumulated fluids may cause lead damage or difficulty
in passing the stylet through the lead.

■

Do not use a sharp object to impart a curve to the distal end of
the stylet.

8 6931 Technical Manual

Necessary hospital equipment – Keep external defibrillation
equipment nearby for immediate use during the acute lead system
testing, implant procedure, or whenever arrhythmias are possible or
intentionally induced during post-implant testing.

Line-powered equipment – An implanted lead forms a direct
current path to the myocardium. During lead implant and testing, use
only battery-powered equipment or line-powered equipment
specifically designed for this purpose, to protect against fibrillation
that may be caused by alternating currents. Line-powered equipment
used in the vicinity of the patient must be properly grounded. Lead
connector pins must be insulated from any leakage currents that may
arise from line-powered equipment.

Second anchoring sleeve – Leads 85 cm or longer feature
2 anchoring sleeves. Use both anchoring sleeves to assure adequate
fixation, see the section “Anchoring the lead” on page 24.

Concurrent devices – Output pulses, especially from unipolar
devices, may adversely affect device sensing capabilities. If a patient
requires a separate stimulation device, either permanent or
temporary, allow enough space between the leads of the separate
systems to avoid interference in the sensing capabilities of the
devices. Previously implanted pulse generators, implantable
cardioverter defibrillators, and leads should generally be explanted.
Refer to “Chronic repositioning or removal” on page 9, for further
information on explanting leads.

Diathermy – People with metal implants such as pacemakers,
implantable cardioverter defibrillators (ICDs), and accompanying
leads should not receive diathermy treatment. The interaction
between the implant and diathermy can cause tissue damage,
fibrillation, or damage to the device components, which could result
in serious injury, loss of therapy, or the need to reprogram or replace
the device.

Chronic repositioning or removal – Chronic repositioning or
removal of leads may be difficult because of fibrotic tissue
development. Return all removed leads, or lead segments, to
Medtronic. If a lead must be removed or repositioned, proceed with
extreme caution.

■

Lead removal may result in avulsion of the endocardium, valve,
or vein.

■

Lead junctions may separate, leaving the lead tip and bare wire
in the heart or vein.

■

Chronic repositioning may adversely affect the low-threshold
performance of a steroid eluting lead.

■

Cap abandoned leads to avoid transmitting electrical signals.

■

For leads that have been severed, seal the remaining lead end
and suture the lead to adjacent tissue.

6931 Technical Manual 9

■

If a helix electrode does not disengage from the endocardium
by rotating the connector pin, rotating the lead body
counterclockwise may withdraw the helix electrode and
decrease the possibility of damage to the cardiovascular
structures during removal.

Connector compatibility – Although the lead conforms to the
International Connector Standards IS-1 and DF-1, do not attempt to
use the lead with any device other than a commercially available
implantable defibrillator system with which it has been tested and
demonstrated to be safe and effective. The potential adverse
consequences of using such a combination may include, but are not
limited to, undersensing cardiac activity and failure to deliver
necessary therapy.

Potential adverse events

The potential adverse events related to the use of transvenous leads
include, but are not limited to, the following patient-related conditions:

■

cardiac perforation

■

cardiac tamponade

■

constrictive pericarditis

■

embolism

■

endocarditis

■

fibrillation or other arrhythmias

■

heart wall rupture

■

hemothorax

■

infection

■

pneumothorax

■

thrombosis

■

tissue necrosis

Other potential adverse events related to the lead include, but are not
limited to, the following:

■

Insulation failure

■

Lead conductor or electrode fracture

■

Lead dislodgment

■

Poor connection to the device, which may lead to oversensing,
undersensing, or a loss of therapy

10 6931 Technical Manual

Clinical study

Clinical data was not collected in the approval process for this lead.
Clinical data from the Models 6947 and 6932 leads support the safety
and efficacy of the Model 6931 lead.

The Model 6931 lead is a downsized version of the Medtronic Sprint
Quattro Secure Model 6947 lead without an SVC defibrillation coil
(same as the Sprint Model 6932 lead). The Model 6931 lead includes
a combination of components used in currently marketed Medtronic
leads with some enhancements. All functional features of the Model
6931 lead have been approved in currently marketed Medtronic
leads. Previous clinical studies have demonstrated titanium nitride
coated electrodes (6931) do not significantly change clinical pacing
thresholds or sensing amplitudes as compared to platinized
electrodes (6947). The overall surface of the defibrillation electrode
falls within the range of currently approved Sprint leads.

Based upon its similarity to the Model 6947 and 6932 leads, the
clinical data from these lead models supports the safety and efficacy
of the Model 6931 lead (Table 1).

Table 1.

Sprint Fidelis Model 6931
features:

Silicone insulation with
polyurethane overlay

Ring electrode for true bipolar
sensing

Steroid eluting Steroid eluting

Active fixation extendable/
retractable helix

a

Standard

Sprint Fidelis Model 6931
features:

Single RV defibrillation coil Single RV defibrillation coil

a

electrode spacing

8 mm tip to ring spacing, 12 mm tip to RV coil spacing

Sprint Quattro Secure Model
6947 clinical data supports:

Silicone insulation with
polyurethane overlay

Ring electrode for true bipolar
sensing

Active fixation extendable/
retractable helix

a

Standard

Sprint Model 6932 clinical
data supports:

electrode spacing

Model 6947 clinical study

The Model 6947 clinical study was a prospective, nonrandomized,
multicenter trial assessing the lead handling and performance of the
Sprint Quattro

The Model 6947 lead was implanted in 80 patients at 15 investigative
centers in the United States and at 2 investigative centers in Canada
between April 27, 2001 and August 2, 2001.

Secure Model 6947 Lead.

6931 Technical Manual 11

Patients were included in this study if they met the following criteria:

1) able to receive a pectoral implant and 2) survived at least one
episode of cardiac arrest due to a ventricular tachyarrhythmia; or had
poorly tolerated, sustained ventricular tachycardia that occurred
spontaneously; or had poorly tolerated, sustained ventricular
tachycardia that could be induced.

Patients studied

The Model 6947 study population consisted of 63 males and
17 females. The mean age was 64.4 years. The most frequently
reported indication for implant was inducible ventricular tachycardia
without sudden cardiac death (SCD) (47.5%). The mean ejection
fraction was 35.5%. The most frequently reported NYHA
classifications were Class I (35.0%) and Class II (36.3%).

Cardiovascular history included coronary artery disease with
myocardial infarction (62.5%), hypertension (58.8%),
cardiomyopathy (65.0%), congestive heart failure (47.5%), syncope/
presyncope (46.3%) and previous cardiac surgery (68.8%).

Objectives

The objectives of the study were to report the following:

■

Pacing thresholds

■

R-wave amplitudes

■

Pacing impedance

■

Lead handling

■

Adverse events

Methods

Pulse width thresholds, R-wave amplitudes, and pacing impedances
were measured at implant and at one month post-implant. Adverse
events were collected throughout the study. A lead handling
questionnaire was completed by the implanting physician at each
implant. The implanting physicians evaluated the performance of the
Model 6947 lead with regard to:

■

Ease of lead insertion into the
vein

■

Ease of helix extension

■

Visibility of helix extension

■

Steerability

■

Torqueability

■

Lead placement time

■

Ability to traverse the tricuspid
annulus

■

Comfort level with handling the
lead

12 6931 Technical Manual

■

Slipperiness of lead surfaces

■

Stiffness of the lead

■

Ease of obtaining adequate
R-wave sensing

■

Ease of obtaining adequate
VF sensing

■

Ease of obtaining adequate
DFTs

■

Overall ease of lead
placement

Results

The mean follow-up duration was 0.96 months (range: 0.00 - 1.71
months) with a cumulative follow-up duration of 76.82 months. The
pace/sense measurements are summarized in Table 2.

Tab l e 2 . Pace/Sense measurements

Implant One month

Pulse-width threshold at one volt

N8061

Median (ms) 0.20 0.20

th

- 75th Percentile (0.20 - 0.20) (0.20 - 0.30)

25

Range (0.03 - 0.60) (0.20 - 0.80)

R-wave amplitude (EGM)

N7864

Median (mV) 8.0 9.3

th

- 75th Percentile (7.0 - 11.0) (7.5 - 12.8)

25

Range (3.0 - 24.0) (3.5 - 20.0)

Pacing lead impedance

N8066

Median (ohms) 564.0 481.0

th

- 75th Percentile (481.0 - 611.0) (444.0 - 521.0)

25

Range (378.0 - 985.0) (323.0 - 985.0)

On the lead handling survey, for all items rated, the adjusted rating of
the Model 6947 lead fell between 1 (very good) and 2 (excellent). The
adjusted rating for each item is an average across physicians,
accounting for multiple responses per physician.

The overall ease of lead placement was considered good, very good,
or excellent by all implanting physicians, with an adjusted rating of 1.7
(the minimum rating on the questionnaire was - 2.0 and the maximum
rating was 2.0).

Observed adverse events

The Sprint Quattro Secure Model 6947 Lead was utilized in a
prospective, nonrandomized, multicenter trial to assess the handling
and performance of the Model 6947 lead.

A total of 22 cardiovascular related adverse events were reported.
Two of the 22 events were ventricular lead-related and both occurred
at implant. One event was a microdislodgement and one was induced
VT as a result of lead manipulation.

Two deaths occurred in this patient group during the follow-up period.
Both deaths were classified as non-sudden cardiac and were judged
to be non-system related by an independent advisory committee.

6931 Technical Manual 13

Model 6947 conclusion

In this clinical study, the Model 6947 lead demonstrated acceptable
clinical performance. Through questionnaire responses, implanting
physicians verified acceptable overall lead performance and handling
during the implant procedure.

Model 6932 (single-coil) clinical study

The following is a summary of the clinical results from the 6932 RV
lead study with respect to the primary study objectives and additional
performance measurements with Active Can ICDs. All of the results
presented are based on an “as randomized” analysis.

Patient characteristics

The results summarize data for 336 patients, who were randomized
(1:1) to either the Model 6932 lead (n=168) or the Model 6936 lead
(n=168) between 6/9/95 and 3/22/96. Commercially available
Medtronic ICDs were the devices used in the study. The mean
follow-up was 2.39 ± 1.96 months with a cumulative follow-up of

803.4 months.

Primary endpoints

Patient characteristics by randomized lead

6932

N=168

Gender

% Male 133 (79.2%) 140 (83.3%)

Age at implant

Mean (years)
Standard deviation (years)

Primary indication

SCD only
VT only
SCD & VT
Other

Primary cardiovascular disease

CAD or MI
Cardiomyopathy only
Primary electrical disease
Other

NYHA classification

Class I/II 142 (84.5%) 137 (81.5%)

Ejection fraction

Mean
Standard deviation

59.4

±12.9

49 (29.2%)
88 (52.4%)
20 (11.9%)

11 (6.6%)

114 (67.9%)

30 (17.9%)

7 (4.2%)

17 (10.1%)

34.8&

±13.0%

6936

N=168

62.1

±11.4

45 (26.8%)
86 (51.2%)
28 (16.7%)

9 (5.4%)

117 (69.6%)

33 (19.6%)

7 (4.2%)

11 (6.6%)

34.9%

±13.4%

14 6931 Technical Manual

Meeting defibrillation implant criterion

Meeting defibrillation implant criterion with the initial lead configuration
was defined as having at least one successful defibrillation at
≤ 22 joules in the first three VF inductions (following a binary search
protocol), or failing that, two successful defibrillations in the next two
VF inductions at ≤ 24 joules. The initial lead configuration was defined
as the initial system tested, allowing no polarity or position changes.
The rate of meeting defibrillation implant criterion with the initial
configuration for the 6932 lead was equivalent to the 6936 lead.

Meeting defibrillation implant criterion with

the initial lead configuration by randomized lead

6932 6936

Observed success rate

Adjusted success rate

b

p-value

a

Including only those patients in whom the implant testing protocol was
fully completed

b

Adjusted for age, sex, ejection fraction, NYHA classification and primary
indication for implant using logistic regression

a

b

99% (143/145) 96% (137/142)

100% 99%

0.077

Pacing thresholds through three months

A pulse-width threshold was measured at 2.8 V at implant,
pre-hospital discharge evaluation (PDE), one month and three
months. The pulse-width threshold for the 6932 lead was significantly
lower than for the 6936 lead at each time point (p=0.0001).

Complication-free survival through three months

Pacing thresholds through 3 months by randomized lead

Pulse width (in msec) @ 2.8 V

Lead Implant PDE 1 month 3 month

6932 N

Adjusted mean

6936 N

Adjusted mean

a

p-value

a

Adjusted for age, sex, ejection fraction and NYHA classification using mixed
effects regression

158

a

0.043

150

a

0.069

0.0001 0.0001 0.0001 0.0001

152

0.049

142

0.109

116

0.057

117

0.205

77

0.063

80

0.198

A complication was defined as an adverse event which required
invasive intervention. The complication-free survival through three
months for the 6932 lead was equivalent to the 6936 lead (p=0.87).

6931 Technical Manual 15

Additional performance measurements with active can ICDs

Implant success

Implant success was achieved if the initial system tested was the
system that was implanted (including polarity and position changes).
For the 6932 lead, implant success with a single lead-Active Can
system was 98% (114/116 patients).

Defibrillation threshold (DFT)

The DFT with the initial lead system was determined following a
binary search protocol (starting with a 12 J shock). For the 6932 lead,
the mean DFT with a single lead-Active Can system was 8.7 J.

Model 6932 conclusions

All of the stated objectives were met in this study. These findings
demonstrate that the Model 6932 lead performance is equivalent to,
or better than the Model 6936 lead performance, and that the
6932 lead is safe and effective for human use.

Directions for use

Proper surgical procedures and sterile techniques are the
responsibility of the medical professional. The following procedures
are provided for information only. Each physician must apply the
information in these instructions according to professional medical
training and experience.

The implant procedure generally includes the following steps:

■

Opening the package

■

Verifying the mechanical functioning of the helix electrode

■

Inserting the lead

■

Positioning the lead

■

Securing the helix electrode into the endocardium

■

Taking electrical measurements and defibrillation efficacy
measurements

■

Anchoring the lead

■

Connecting the lead

■

Placing the device and leads into the pocket

■

Post-implant evaluation

Opening the package

Use the following steps to open the sterile package and inspect
the lead:

1. Within the sterile field, open the sterile package and remove the
lead and accessories.

2. Inspect the lead. Leads shorter than 85 cm should have
1 anchoring sleeve on the lead body. Leads 85 cm or longer
should have 2 anchoring sleeves on the lead body.

16 6931 Technical Manual

Verifying the mechanical functioning of the
helix electrode

Note: The package includes 2 tools, the Quick Twist tool assembled

on the lead and the white fixation tool. Either tool may be used to
verify the mechanical functioning of the helix electrode. The choice of
tool is left to the discretion of the physician.

Before implant, verify the mechanical functioning of the helix
electrode using the following steps:

1. Attach either the Quick Twist tool or the white fixation tool to the
lead. Ensure that the stylet is inserted into the lead and
proceed as indicated, according to the tool being used.

a. Quick Twist tool: Push the Quick Twist tool onto the IS-1

connector pin (Figure 1).

Figure 1.

b. White fixation tool: Press both legs of the white fixation

tool together and place the most distal hole on the IS-1
connector pin (Figure 2).

Figure 2.

2. Hold the IS-1 connector leg of the lead with the thumb on one
side and 4 fingers on the other side. Keep the lead body and
the IS-1 connector leg as straight as possible (Figure 2).
Ensure that the stylet is fully inserted, then rotate the selected
fixation tool clockwise until the helix electrode is fully extended
(Figure 3a or Figure 3b). When the helix electrode is fully
extended, approximately 1.5 to 2 helix coils are exposed.

6931 Technical Manual 17

a

b

Figure 3.

Caution: Do not severely bend the IS-1 connector leg or the
lead body while extending the helix electrode (Figure 4). If the
lead is bent on either side of the lead bifurcation during helix
electrode extension or retraction, the lead may be damaged.

Figure 4.

Caution: Overrotating the connector pin after the helix
electrode is fully extended may damage the lead.

Note: To determine the number of rotations applied to the lead,
count the number of rotations of the white flap on the Quick
Twist tool. The number of necessary rotations is equivalent to
the number required for the white fixation tool. See
“Specifications (nominal)” on page 27 for the maximum number
of rotations to extend or retract the helix electrode.

18 6931 Technical Manual

The number of rotations required to extend the helix electrode
increases proportionately with the length of the lead. Additional
curvatures made to the stylet may increase the number of
rotations needed to extend or retract the helix electrode. Refer
to the section “Specifications (nominal)” on page 27, for the
maximum number of rotations to extend or retract the helix
electrode.

During the initial helix electrode extension, the helix electrode
may extend suddenly due to accumulated torque in the lead, or
the helix electrode may require additional turns for extension.

3. Disconnect the selected fixation tool from the connector pin and
release the proximal end of the lead body. Allow several
seconds for relief of the residual torque in the lead.

4. After allowing for relief of the residual torque, reattach the
selected fixation tool and rotate it counterclockwise until the
helix electrode tip is retracted into the sheath.

Inserting the lead

Caution: Use care when handling the lead during insertion.

■

Do not severely bend, kink, or stretch the lead.

■

Do not use surgical instruments to grasp the lead or
connector pins.

Insert the lead using the following techniques:

1. Select a site for lead insertion. The lead may be inserted by
venotomy through several different venous routes, including the
right or left cephalic vein or the external or internal jugular vein.
Use the cephalic vein whenever possible to avoid lead damage
in the first rib or clavicular (thoracic inlet) space.

Caution: Certain anatomical abnormalities, such as thoracic
outlet syndrome, may also precipitate pinching and subsequent
fracture of the lead.

Caution: When using a subclavian approach, avoid techniques
that may damage the lead.

■

Place the insertion site as far lateral as possible to avoid
clamping the lead body between the clavicle and the first rib
(Figure 5).

Figure 5.

■

Do not force the lead if significant resistance is encountered
during lead passage.

6931 Technical Manual 19

■

Do not use techniques such as adjusting the patient’s
posture to facilitate lead passage. If resistance is
encountered, it is recommended that an alternate venous
entry site be used.

2. Insert the tapered end of a vein lifter into the incised vein and
gently push the lead tip underneath and into the vein (Figure 6).

Note: A percutaneous lead introducer (PLI) kit may be used to
facilitate insertion. Refer to the technical manual packaged with
an appropriate percutaneous introducer for further instructions.

Figure 6.

3. Advance the lead into the right atrium using a straight stylet to
facilitate movement through the veins.

Positioning the lead

Caution: Use care when handling the lead during positioning.

■

Do not severely bend, kink or stretch the lead.

■

Do not use surgical instruments to grasp the lead or
connector pins.

Use the following steps to position the lead:

1. After the lead tip is passed into the atrium, advance the lead
through the tricuspid valve. Replacing the straight stylet with a
gently curved stylet may add control in maneuvering the lead
through the tricuspid valve.

Caution: Do not use a sharp object to impart a curve to the
distal end of the stylet. Imparting a curve to the stylet can be
accomplished with a smooth-surface, sterile instrument
(Figure 7).

Figure 7.

20 6931 Technical Manual

Note: Passing the lead tip through the tricuspid valve or
chordae tendineae may be difficult due to the flexible nature of
the lead body. Rotating the lead body as the tip passes through
the valve may facilitate passage.

2. After the lead tip is in the ventricle, the curved stylet may be
replaced with a straight stylet. Withdraw the stylet slightly, to
avoid using excessive tip force while achieving final electrode
position. Avoid known infarcted or thin wall areas, to minimize
the occurrence of perforation.

3. Proper positioning of the helix electrode is essential for stable
endocardial pacing. A satisfactory position usually is achieved
when the lead tip points straight toward the apex, or when the
distal end dips or bends slightly. Use fluoroscopy (lateral
position) to ensure that the tip is not in a retrograde position or
lodged in the coronary sinus.

Note: With the helix electrode retracted, the distal end of the
lead may be used to map a desirable site for electrode fixation.
Mapping may reduce the need to repeatedly extend and fixate
the helix electrode.

4. After placing the lead in a satisfactory position, extend the helix
electrode by following the procedure in the section “Securing
the helix electrode into the endocardium” on page 21.

Securing the helix electrode into the endocardium

Note: The package includes 2 tools, the Quick Twist tool assembled

on the lead and the white fixation tool. Either tool may be used to
secure the helix electrode into the endocardium. The choice of tool is
left to the discretion of the physician.

Secure the helix electrode using the following techniques:

1. Attach either the Quick Twist tool or the white fixation tool to the
lead. Ensure that the stylet is inserted into the lead and
proceed as indicated, according to the tool being used.

a. Quick Twist tool: Push the Quick Twist tool onto the IS-1

connector pin. (Figure 1).

b. White fixation tool: Press both legs of the white fixation

tool together and place the most distal hole on the IS-1
connector pin (Figure 2).

2. Press the lead tip against the endocardium by gently pushing
the stylet and lead at the vein entry site.

3. Rotate the selected fixation tool clockwise until the helix
electrode is fully extended (see Figure 3a or Figure 3b).

Caution: Do not severely bend the IS-1 connector leg or the
lead body while extending the helix electrode (Figure 4). If the
lead is bent on either side of the lead bifurcation during helix
electrode extension or retraction, the lead may be damaged.

Use fluoroscopy to verify electrode extension (Figure 8). The
fluoroscope head may need to be rotated to obtain an
adequate view.

6931 Technical Manual 21

Closing of the space between the indicator stop (A) and the
indicator ring (B) implies complete extension of the
helix electrode.

VISUAL

VISUAL

Fully Retracted

FLUOROSCOPIC

Fully Extended

FLUOROSCOPIC

Figure 8.

A B

AB

Caution: Exceeding the maximum number of rotations may
damage the lead. The maximum number of rotations required
to fully extend or retract the helix electrode is variable; refer to
the section, “Specifications (nominal)” on page 27, for the
maximum number of rotations.

Caution: Prolonged implant procedures or multiple
repositionings may allow blood or body fluids to build up on the
helix electrode mechanism. This may result in an increased
number of rotations required to extend or retract the
helix electrode.

4. Remove the selected fixation tool from the IS-1 connector pin
and release the proximal end of the lead body. Allow several
seconds for relief of the residual torque in the lead.

5. To assure helix electrode fixation, leave the stylet in place, hold
the lead by the connector, and carefully rotate the lead body in
2 clockwise rotations.

6. Partially withdraw the stylet.

7. Obtain electrical measurements to verify satisfactory
placement and electrode fixation. Refer to the section “Taking
electrical measurements and defibrillation efficacy
measurements” on page 23.

8. Verify that the lead is affixed. Gently pull back on the lead and
check for resistance to verify fixation. A properly affixed helix
electrode will remain in position. If the helix electrode is not
properly affixed, the lead tip may become loose in the right
ventricle.

9. If repositioning is required, reattach the selected fixation tool
and rotate counterclockwise until the helix electrode is
retracted. Use fluoroscopy to verify withdrawal of the helix
electrode before attempting to reposition.

10. After final positioning, remove the stylet and the Quick Twist
tool completely. When removing the Quick Twist tool, grip the
lead firmly just below the connector pin to help prevent lead
dislodgment.

22 6931 Technical Manual

11. Obtain final electrical measurements. Refer to the section
“Taking electrical measurements and defibrillation efficacy
measurements” on page 23.

Taking electrical measurements and defibrillation
efficacy measurements

Caution: Prior to taking electrical or defibrillation efficacy

measurements, move objects made from conductive materials, such
as guide wires, away from all electrodes. Metal objects, such as guide
wires, can short a lead and an active implantable device, causing
electrical current to bypass the heart and possibly damage the
implantable device and lead.

Use the following steps to take electrical measurements:

1. Ensure that the Quick Twist tool is disconnected from the IS-1
connector pin.

2. Attach a surgical cable to the lead connector pin.

3. Use a testing device, such as a pacing system analyzer, for
obtaining electrical measurements. For information on the use
of the testing device, consult the product literature for
that device.

In order to demonstrate reliable defibrillation efficacy, obtain final
defibrillation measurements for the lead system.

Tab l e 3 . Recommended measurements at implant

(when using a pacing system analyzer)

Measurements required Acute

Capture threshold
(at 0.5 ms pulse width) ≤ 1.0 V ≤ 3.0 V

Pacing impedance 200 - 1000 ohms 200 - 1000 ohms

Filtered R-wave amplitude
(during sinus rhythm)

Slew rate

a

< 30 days after implant.

b

> 30 days after implant.

a

lead system

≥ 5mV ≥ 3mV

≥ 0.75 V/s ≥ 0.45 V/s

Chronicb lead system

If initial electrical measurements deviate from the recommended
values, it may be necessary to repeat the testing procedure
15 minutes after final positioning. Initial electrical measurements may
deviate from the recommended values:

■

Initial impedance values may exceed the measuring
capabilities of the testing device, resulting in an error message.

■

Values may vary depending upon lead type, implantable device
settings, cardiac tissue condition, and drug interactions.

If electrical measurements do not stabilize to acceptable levels, it may
be necessary to reposition the lead and repeat the testing procedure.

6931 Technical Manual 23

In order to keep patient morbidity and mortality to a minimum,
patients should be rescued promptly with an external defibrillator if
the implanted lead system fails to terminate a VF episode. At least
5 minutes should elapse between VF inductions.

For more information on obtaining electrical measurements, consult
the technical manual supplied with the testing device.

Anchoring the lead

Caution: Use care when anchoring the lead.

■

Use only nonabsorbable sutures to anchor the lead.

■

Do not attempt to remove or cut the anchoring sleeve from the
lead body.

■

During lead anchoring, take care to avoid dislodging the
lead tip.

■

Do not secure sutures so tightly that they damage the vein,
lead, or anchoring sleeve (Figure 9).

■

Do not tie a suture directly to the lead body (Figure 9).

Figure 9.

Use the following steps to anchor the lead using all 3 grooves:

Note: The anchoring sleeves contain a radiopaque substance, which
allows visualization of the anchoring sleeve on a standard x-ray and
may aid in follow-up examinations.

1. Position the distal anchoring sleeve against or near the vein.

2. Secure the anchoring sleeve to the lead body by tying a suture
firmly in each of the 3 grooves (Figure 10).

Figure 10.

3. Use at least 1 additional suture in 1 of the grooves to secure the
anchoring sleeve and lead body to the fascia.

24 6931 Technical Manual

4. A second anchoring sleeve is provided with leads 85 cm or
longer. For abdominal implants, redundant lead body (for
example, a curve for strain relief) should be placed just proximal
to the first anchoring sleeve. Then, the second anchoring
sleeve may be lightly sutured to the lead body and fascia to hold
the curve in place. This procedure helps isolate the vein entry
site from tension on the proximal end of the lead body.

5. A slit anchoring sleeve may be used in the device pocket to
secure excess lead length. First, secure the anchoring sleeve
to the lead body. Then, orient the slit toward the fascia and
secure the anchoring sleeve to the fascia with sutures.

Connecting the lead

Use the following steps to connect the lead to an implantable device:

1. Carefully remove the stylet and Quick Twist tool. When
removing the stylet and Quick Twist tool, grip the lead firmly just
below the connector pin, to prevent dislodgment.

2. Insert the lead connectors into the connector block. Consult the
product literature packaged with the implantable device for
instructions on proper lead connections.

Placing the device and leads into the pocket

Caution: Use care when placing the device and leads into

the pocket.

■

Ensure that the leads do not leave the device at an acute angle.

■

Do not grip the lead or device with surgical instruments.

■

Do not coil the lead. Coiling the lead can twist the lead body and
may result in lead dislodgment (Figure 11).

Figure 11.

Use the following steps to place the device and leads into the pocket:

1. To prevent undesirable twisting of the lead body, rotate the
device to loosely wrap the excess lead length (Figure 12).

6931 Technical Manual 25

Figure 12.

2. Insert the device and leads into the pocket.

3. Before closing the pocket, verify sensing, pacing,
cardioversion, and defibrillation efficacy.

Post-implant evaluation

After implant, monitor the patient’s electrocardiogram until the patient
is discharged. If a lead dislodges, it usually occurs during the
immediate postoperative period.

Recommendations for verifying proper lead positioning include x-rays
and pacing/sensing thresholds taken at pre-hospital discharge,
3 months after implant, and every 6 months thereafter.

In the event of a patient death, explant all implanted leads and
devices and return them to Medtronic with a completed Product
Information Report form. Call the appropriate phone number on the
back cover if there are any questions on product handling
procedures.

26 6931 Technical Manual

Detailed device description

Specifications (nominal)

Parameter Model 6931

Ty pe Tr ip o la r

Position Right ventricle

Fixation Extendable/Retractable helix

Length 40-110 cm

Connectors Unipolar: DF-1

Bipolar: IS-1

Materials Conductors: MP35N coil

Insulation: Silicone, ETFE

Electrodes (pace, sense): Titanium nitride coated

DF-1 pin: Stainless steel

IS-1 pin and ring: Stainless steel

Steroid Type: Dexamethasone acetate

Steroid binder: Silicone

Conductor resistances Pacing (unipolar): 21.6 Ω (65 cm)

Pacing (bipolar): 68.6 Ω (65 cm)

Defibrillation: <2.4 Ω (65 cm)

Helix length (extended) 1.8 mm

Diameters Lead body: 2.2 mm

Lead introducer (recommended size)

without guide wire: 7.0 French

with guide wire: 9.0 French

MP35N composite cables

Overlay: Polyurethane

platinum iridium

RV coil: Platinum-clad tantalum

Amount: 1.0 mg maximum

Tip: 2.2 mm

Helix: 1.2 mm

Maximum number of rotations to extend or retract the helix electrode

Lead length Number of rotations

52 cm 16

58 cm 18

65 cm 20

75 cm 22

100 cm 27

6931 Technical Manual 27

Specifications drawing (nominal)

12 mm

8 mm

Helix electrode
Surface area: 4.2 mm

Ring electrode

Surface area: 20.2 mm

2

2

RV coil electrode

Length: 62 mm
Surface area: 513 mm

2

Electrical shadow area: 430 mm

Anchoring sleeve

Note: Leads 85 cm or

longer have 2
anchoring sleeves

2

DF-1 connector
(red band)
Note: Connector

pin is common to
RV coil electrode

28 6931 Technical Manual

IS-1 BI connector
Note: Connector pin is common

to tip electrode; connector ring is
common to ring electrode

Medtronic warranty

For complete warranty information, see the accompanying warranty
document.

Service

Medtronic employs highly trained representatives and engineers
located throughout the world to serve you and, upon request, to
provide training to qualified hospital personnel in the use of Medtronic
products. Medtronic also maintains a professional staff to provide
technical consultation to product users. For medical consultation,
Medtronic can often refer product users to outside medical
consultants with appropriate expertise. For more information, contact
your local Medtronic representative, or call or write Medtronic at the
appropriate address or telephone number listed on the back cover.

6931 Technical Manual 29

World Headquarters

Medtronic, Inc.
710 Medtronic Parkway
Minneapolis, MN 55432-5604
USA
Internet: www.medtronic.com
Tel. [phone]
Fax [phone]

Medtronic USA, Inc.

Toll-free in the USA (24-hour
technical consultation for
physicians and
medical professionals)
Bradycardia: 1-800-505-4636
Tachycardia: 1-800-723-4636
Heart Failure: 1-800-505-4636

Europe/Africa/Middle East
Headquarters

Medtronic Europe Sàrl
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Case Postale
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Internet: www.medtronic.co.uk
Tel. [phone]
Fax [phone]

Medtronic E.C. Authorized
Representative/Distributed by

Medtronic B.V.
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The Netherlands
Tel. [phone]
Fax [phone]

Asia

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Tel. [phone]
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Aust ralia

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Tel. [phone]
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Canada

Medtronic of Canada Ltd.
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Mississauga, Ontario L5N 1W3
Tel. [phone]
Fax [phone]
Toll-free in Canada:
1-800-268-5346

Japan

Medtronic Japan
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Kawasaki, Kanagawa 210-0913
Japan
Tel. [phone]
Fax [phone]

*A09204001*

© Medtronic, Inc. 2004
All Rights Reserved

A09204001
2004-09-14