Surgeon Procedure Orientation

1
Surgeon Procedure Orientation
CO2 Heart Laser Transmyocardial Revascularization
(TMR)
2
What is TMR?

• Transmyocardial Revascularization
• The process of creating channels through the
  myocardium resulting in an opening into the left
  ventricle which allows oxygen rich blood from
  within the left ventricle to perfuse out into the
  ischemic area of the myocardium.

3
Recommendation for Use of the C02 Heart Laser

• Recommendations for Transmyocardial
• Revascularization as Sole Therapy
• Class I
• Patients with an ejection fraction greater than
  0.30 and CCS
• class III or IV angina that is refractory to
  maximal medical
• therapy. These patients should have reversible
  ischemia of
• the lest ventricular free wall and coronary
  artery disease
• corresponding to the regions of myocardial
  ischemia. In all
• regions of the myocardium, the coronary disease
  must not
• be amenable to CABG or percutaneous transluminal
  
• angioplasty either as a result of (1) severe
  diffuse disease,
• (2) lack of suitable targets for
  completerevascularization, or
• (3) lack of suitable conduits for complete
  revascularization
• (level of evidence A).

The Society of Thoracic Surgeons Practice
Guideline Series Transmyocardial
LaserRevascularization Charles R. Bridges, MD,
ScD, Keith A. Horvath, MD, William C. Nugent,
MD, David M. Shahian, MD, Constance K. Haan, MD,
Richard J. Shemin, MD, Keith B. Allen, MD, and
Fred H. Edwards, MD
4
Recommendations for Use of the C02 Heart Laser
Recommendations for Transmyocardial Revascularizat
ion as Sole Therapy

• Class IIB
• Patients who otherwise have class I indications
  for
• TMR but who have either
• a. Ejection fraction less than 0.30 with or
  without
• insertion of an intraaortic balloon pump (level
  of
• evidence C).
• b. Unstable angina or acute ischemia
  necessitating
• intravenous antianginal therapy (level of
  evidence B).
• c. Patients with class II angina (level of
  evidence
• C).

The Society of Thoracic Surgeons Practice
Guideline Series Transmyocardial Laser
Revascularization Charles R. Bridges, MD, ScD,
Keith A. Horvath, MD, William C. Nugent,
MD, David M. Shahian, MD, Constance K. Haan, MD,
Richard J. Shemin, MD, Keith B. Allen, MD, and
Fred H. Edwards, MD
5
Recommendations for Use of the C02 Heart Laser
Recommendations for Transmyocardial Revascularizat
ion as Sole Therapy

• Class III
• Patients without angina to with class I angina
  (level of evidence C).
• Acute evolving myocardial infarction or recent
  transmural or nontransmural myocardial infarction
  (level of evidence C).
• Cardiogenic shock defined as a systolic blood
  pressure less than 80 mm Hg or a cardiac index of
  less than 1.8 L min-1 m-2 (level of evidence
  C).
• Uncontrolled ventricular or supraventricular
  tachyarrythmias (level of evidence C).
• Decompensated congestive heart failure (level of
  evidence C).

The Society of Thoracic Surgeons
PracticeGuideline Series Transmyocardial Laser
Revascularization Charles R. Bridges, MD, ScD,
Keith A. Horvath, MD, William C. Nugent,
MD, David M. Shahian, MD, Constance K. Haan, MD,
Richard J. Shemin, MD, Keith B. Allen, MD, and
Fred H. Edwards, MD
6
Recommendations for Use of the C02 Heart Laser
Recommendations for Transmyocardial Revascularizat
ion as an Adjunct to Coronary Artery Bypass
Grafting

• Class IIA
• Patients with angina (class I-IV) in whom CABG is
• the standard of care who also have at least one
• accessible and viable ischemic region with
  demon-
• strable coronary artery disease that cannot be
  by-
• passed either because of (1) severe diffuse
  disease,
• (2) lack of suitable targets for complete
  revascular-
• ization, or (3) lack of suitable conduits for
  complete
• revascularization (level of evidence B).

The Society of Thoracic Surgeons Practice
Guideline Series Transmyocardial Laser
Revascularization Charles R. Bridges, MD, ScD,
Keith A. Horvath, MD, William C. Nugent,
MD, David M. Shahian, MD, Constance K. Haan, MD,
Richard J. Shemin, MD, Keith B. Allen, MD, and
Fred H. Edwards, MD
7
Recommendations for Use of the C02 Heart Laser
Recommendations for Transmyocardial Revascularizat
ion as an Adjunct to Coronary Artery Bypass
Grafting

• Class IIB
• Patients without angina in whom CABG is the
• standard of care who also have at least on
  accessi-
• ble and viable ischemic region with demonstrable
• coronary artery disease that cannot be bypassed
• either because of (1) severe diffuse disease,
  (2) lack
• of suitable conduits for complete
  revascularization
• (level of evidence C).
• Class III
• Patients in whom CABG is not the standard of care
• (level of evidence C).

The Society of Thoracic Surgeons Practice
Guideline Series Transmyocardial
LaserRevascularization Charles R. Bridges, MD,
ScD, Keith A. Horvath, MD, William C. Nugent,
MD, David M. Shahian, MD, Constance K. Haan, MD,
Richard J. Shemin, MD, Keith B. Allen, MD, and
Fred H. Edwards, MD
8
Relative Indications and Contraindications to TMR

• Relative indications may include
• Stabilized acute conditions
• EF lt 25 with left main disease or 90-100 LAD
  stenosis
• when LV function is treated with
  revascularization
• IV meds administered to
• decrease anginal pain
• decrease myocardial edema
• increase perfusion
• Combination of factors increased cardiac enzymes
  CK of 500 and
• EF of 20
• Contraindications include
• Cardiogenic shock
• EF lt25 and increased enzymes with CK 800-1000
  Troponin 25
• Severe or uncontrolled ventricular arrhythmias
• De-compensated congestive heart failure
• Acute myocardial infarction

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CO2 Laser TMR Procedure Plan
Document physiologic and anatomical
characteristics and ask yourself this question
Will I leave behind any ischemic untreated
areas?

• Physiological and Anatomical Assessment
• Review SPECT/MRI/PET/cine angiogram/SPY angiogram
• Assess the severity of overall patient condition
  (angina or anginal equivalent)
• Assess impact of collateral flow, competitive
  flow, and vessel size
• Assess microvascular perfusion to coronary bed
• Note viable yet ischemic myocardium
• Note the number and type of diseased/stenotic
  targets present
• Visually inspect the heart to locate and assess
  target vessels
• Note the movement / contraction of the
  ventricular wall
• The surgeon may opt to image native coronary
  circulation utilizing SPY intra-operative
  angiography

10

• Surgical considerations
• for use of
• CO2 Heart Laser/TMR
• At what point in the operation
• will TMR be completed?

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Scenario 1 Post CABG

• Beating heart
• Direct coronary artery bypass has been performed
  on treatable areas
• Availability of SPY intra-operative angiography
• Post protamine
• Pros
• CABG is completed and surgeon able to thoroughly
  assess the quality of the anastomoses
• SPY intra-operative angiography is an excellent
  way to
• Evaluate distal outflow and regional perfusion
• Document flow to the specific region targeted for
  TMR
• Note function of bypass graft(s)
• Note availability of suitable targets post bypass

• Cons
• Potential delay in the procedure due to channel
  closing after patient comes off pump

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Scenario 2 Pre-CABG

• Pts ECG is monitored through the TMR machine to
  synchronize with R wave.
• Pts chest is opened, the heart is examined,
  target area(s) located
• TMR initiated to those regions indicated
• Pros
• Expedites procedure and operative time
  alleviates pressure of time constraints
• Major reduction of the potential for ventricular
  arrhythmias with gated ECG
• Pre-heparinazation, channels have an opportunity
  to seal
• Cons
• Potential for hemodynamic instability
  positioning may cause decreased SBP and decreased
  LV function.
• May need to perform 3-4 channels and then rest
  the heart causing loss of positioning
• Lifting the heart may cause no sensing of the R
  wave (If this occurs, put the heart down,
  increase ECG gain, place ventricular pacing wires
  on the heart)

13
Intra-operative Assessment with SPY

• The addition of SPY allows the surgeon to make a
  more accurate clinical judgment as to when to, or
  when not to, perform TMR
• SPY images document the basis for decision making
• SPY provides the ability to evaluate and document
  flow characteristics and areas not amenable to
  direct coronary bypass
• Without SPY
• Note decreased wall motion
• Note diminished pulsatile flow
• Via Doppler TTFM or visual inspection
• With SPY
• Real time visualization of flow to the distal
  myocardium
• Areas that lack fluorescence, or in which
  fluorescence dissipates very slowly may be
  targets indicated for TMR to improve
  revascularization
• Imaging record of indication for TMR
• Rationale Without adequate blood flow to a
  particular region, the heart may be prone to
  arrhythmias, poor targets may be prone to early
  graft closure.

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Surgical Setup

• TEE is used to evaluate the function of the left
  ventricle and the cardiac valves.
• The CO2 Heart Laser is calibrated, sterile cover
  applied, and joules set per surgeons
  specifications
• Team work is essential to successful surgical
  technique
• Surgeon aiming the hand piece - States Arm
  Laser
• Circulator running the laser Responds Laser
  Armed and Reports shots fired
• Anesthesiologist with TEE properly placed
  Responds Hit or Miss as laser fired

15
Surgical Technique

• TMR is performed in the target areas of the left
  ventricle.
• Posterior lateral section is performed first
• Use an angled handpiece at 12-15 joules (very
  little fat)
• Moving from base of the heart to apex and make
  8-10 channels
• When completed, place a 4x4 to tamponade bleeding
  points
• Lateral area is performed second.
• More channels can be made in this area as it a
  wider area. May place 3 channels across
• Recommendation set pulse width to 20 joules
  initially and adjust as needed
• Anterior-lateral region
• A straight hand piece may be used with 12-15
  joules delivered
• If the septum is lased 3-4 shots may be
  administered at 15-18 joules
• It is important during the TMR procedure, that
  all safety precautions are instituted, and a
  protocol is established between the surgeon and
  the operator of the laser

Horvath, April 23, 2007 TMR
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Surgical Technique Review

• The goal is to achieve transmural penetration
  with the least amount of energy creating
  decreased thermal heart damage
• When considering how much of the heart should be
  lased, the main objective is to get flow from a
  vascularized area to a non- vascularized area to
  generate collateral flows
• Number of joules can vary between 8-40 joules.
  Variance on the size and appearance of the heart.
  For example, a fatty exterior requires more
  joules. Commonly 8-20 are used
• With an excessively fatty heart, it may also help
  to use an apical suction device
• If necessary, a ß-blocking agent can be infused
  intravenously to reduce the force and rate of
  cardiac contraction. Anti-arrhythmic medications
  such as amiodarone may be used as well
• The TMR procedure can be completed at any point
  throughout the CABG procedure
• Excessive energy from the laser is absorbed by
  blood and water

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Tips

• By positioning the device or arm over the
  surgeons right shoulder, accessibility to all
  areas of the heart is enhanced
• Operator should hold behind the ridge of the hand
  piece to avoid injury to fingers
• If the toe pedal is held down too long, the
  device will not arm
• The toe pedal must be held down long enough for
  the ECG and firing of the laser to be in
  synchronization.
• Lifting the heart may cause a loss of ECG
  activity
• A saline filled glove behind the heart may aid in
  positioning and conductivity
• Use eye protection for the patient and cover
  shiny metal objects on the field to avoid
  reflection and misfiring of the laser
• Ensure staff uses eye protection
• A tongue depressor with elastic bands may be
  helpful for traction while positioning the heart
• For proper documentation consider dividing the
  heart into zones 1-4 and then place 8-10 shots
  per zone
• When laser is on the field
• May use a constant guide light when laser is
  UNARMED
• May use a flashing guide light when laser is
  ARMED

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Rx only. Federal law further restricts the use
of this device to practitioners who have been
trained in laser heart surgery including laser
system calibration and operation. Use of this
device is restricted to patients who have signed
a consent form to ensure that the risks
associated with TMR have been fully explained and
understood. TMR is indicated for the treatment
of patients with stable angina(Canadian
Cardiovascular Class III or IV) refractory to
medical treatment and secondary to objectively
demonstrated coronary artery atherosclerosis and
with a region of the myocardium not amenable to
direct coronary revascularization WARNING In
the randomized clinical study involving 151 TMR
surgeries, unstable angina was associated with
22 peri-operative mortality compared to 1 in
patients with stable angina. See instructions
for use for full prescribing information. Manufac
tured by PLC Medical Systems distributed by
Novadaq Technologies Inc. Novadaq Technologies
Inc. (TSX NDQ), a developer of real-time medical
imaging systems and image guided therapies for
the operating room, wholly-owned U.S. subsidiary,
Novadaq Corp., is the exclusive distributor of
the PLC Medical System Inc.s HEART LASER
SYSTEM for Transmyocardial Revascularization
(TMR) in the United States.
2585 Skymark Avenue Suite 306 Mississauga ON
L4W 4L5 Canada