Nged3chap3

General overview

  • How to select guide?
    • Size of ascending aorta
    • Location of ostium
    • Tortuosity proximal to target
    • Calcification proximal to target
    • Lesion characteristics
  • Guide support
    • Passive
      • Due to design of guide
      • Two components-
        • Backup from opposite aortic wall
        • Stiffness
    • Active
      • By operator manipulation
      • Two components
        • Making the guide conform to aortic root
        • Deep engagement
  • JL guide
    • Curves
      • Primary- 90 deg
      • Secondary- 180 deg
      • Tertiary- 35 deg
    • Engages LM easily
    • Coaxial alignment is difficult due to 90 deg primary curve
    • Often, support for PCI is inadequate
  • Amplatz guide
    • Secondary curve rests against
      • AL- non-coronary posterior cusp
      • AR- left cusp
    • Good support for PCI
    • Used for
      • Short LM
      • Superior takeoff
      • Downgoing LCx
      • Downgoing RCA
    • Chance of ostial dissection due to downward tip
  • Multipurpose guide
    • Single minor bend at tip
    • Uses-
      • High LM takeoff
      • Downward RCA
  • EBU-
    • Long secondary curve abuts opposite aortic wall- very good support
    • Long tip forms straight line with coronary

Guide manipulations

  • Standard safety techniques
    • After putting Y adapter-
      • First bleed back generously
      • Then flush
      • Then look for bubbles
    • During procedure
      • Frequently flush
      • Always look for dampening
    • During injection    
      • Keep syringe pointed down, so air will not go in
      • Always look for reflux
    • When withdrawing balloon/ stent/ TEC
      • Watch tip, especially if proximal plaque
      • Look for dampening
  • Tortuous iliac artery
    • If torque is not transmitting
      • Wait for torque to transmit
      • Gently move guide in and out for a very short distance
    • Put long sheath (23 cm)
    • Manipulate with 038 long J through Y adapter
  • Dampening of arterial pressure
    • Ventricularization- diastolic BP drop
    • Dampening- systolic and diastolic BP drop
    • Causes-
      • Ostial lesion- most common
      • Coronary spasm
      • Guide is too big for artery
        • Downsize guide or
        • Put guide with side holes
      • Non- coaxial alignment
      • Guide is deep in
        • Make guide out or
        • Push in balloon/ stent/ TEC
    • Guide with side holes
      • Suboptimal opacification
      • More contrast needed
      • Decreased backup from aortic root (rare)
      • Kinking at sideholes (rare)
  • Checking backup potential
    • Advance guide a bit
      • Further intubation- good backup
      • Prolapsing out- poor backup
  • Active intubation
    • Other names- active support, power position
    • Do only if
      • Large artery
      • No proximal lesion
    • Do only if coaxial alignment is not possible
    • Chance of proximal dissection or thrombosis is high
    • Osteoproximal stent placement may not be possible

Judkins guide

  • JL
    • Size is cm between primary and secondary curves
    • 3.5 cm for Asians, 4 cm for Caucasians
    • Enter by gentle counterclockwise rotation
    • Size is determined by
      • Size of aortic root- lower size for smaller root and vice versa
      • Direction of LAD- lower size for superiorly directed LAD
    • Smaller sized JL will point to superior wall and dissect here with injection, especially in elderly with unsuspected plaques
    • Tip should point up. If it points down, the guide is too large.
    • Small JL will double back
  • JR
    • Rotate clockwise while withdrawing to engage
    • Check in RAO 30 deg- tip will be a head-on ring if coaxial

Amplatz guide

  • Sizes
    • 1- small root
    • 2- normal root
    • 3- large root
  • Relation between guide tip and ostium
    • Tip above ostium- larger than needed sized guide
    • Tip into ostium- correct size
    • Tip below ostium- lesser than needed size
    • If size is not correct, do not attempt forceful engagement
  • If RCA ostium is very high, AL may be used
  • Engaging-
    • Keep wire till guide reaches sinus
    • Advance guide to reach ostium level
    • For AL- rotate counter clockwise
    • Then retract to engage
  • Optimal position- closed loop
  • Undesirable position- open loop with tip pointing down inferior wall of ostium
  • Disengagement
    • Be very careful
    • Simple withdrawal is never to be done- tip advances further- dissection
    • Advance guide to prolapsed out of ostium
    • Then rotate guide to go away from coronary area
    • Then withdraw
    • Less likely to cause damage if retracted over a wire
  • Removing balloon
    • 1st option- while pulling out balloon, simultaneously push the guide to prolapsed it out, all the time watching fluoro
    • 2nd option- push balloon- guide goes back- pull balloon slowly watching whether guide comes in- if so, push balloon again- repeat this again and again

Multipurpose guide    

  • For engaging left
    • 30 deg RAO
    • Place in posterior sinus
    • Tip pointed to spine
    • Advance till guide buckles
    • Rotate clockwise
    • Now guide enters left cusp
    • Counter clockwise rotation to enter LAD
  • For engaging right
    • 45 deg RAO
    • Place in left cusp
    • Tip pointed to anterior and right
    • Rotate clockwise and slightly withdraw

EBU

  • Keep wire till guide goes into sinus

 

Diagnostic catheter for LM lesions

  • Suspect LM lesion when
    • Rest angina
    • Angina at low level of activity
    • Post prandial angina
    • Angina at early stage of TMT
    • Diffuse ST depression in TMT
    • During TMT, BP does not increase or decreases
  • Tips
    • Use short tip JL
    • Keep below ostium and inject 10 cc contrast
    • Then slowly engage avoiding uncontrolled jump into LM
    • Inject only if no ventricularization or damping
    • Inject only 2 to 3 cc
    • Only AP cranial and AP caudal views are needed for surgeon
    • Do not hit and run- catheter tip may be under a plaque- dissection may occur

Guide for LAD lesions

  • JL is a good option as it points superiorly

Guide for LCx lesions

  • Short LM and no acute angle of LCx origin- select JL.
  • Long LM or acute angle of LCx origin- select EBU. JL is not a good option as it points superiorly
  • If JL is not hooking well
    • Rotate clockwise
    • Select larger size
  • AL is also a good option.
  • Power position for JL-
    • Better than this will be EBU or AL.
    • Do over stent or balloon
    • Gently push guide with gentle clockwise torque till whole curve sits well in left sinus.
    • Now guide looks like AL.
    • After purpose, remove by opposite torque and withdrawal
    • Do only if no proximal or ostial disease

Guide for RCA lesions

  • Takeoff
    • Horizontal- usual one
    • Upward looking- shepherd’s crook
    • Downward looking
  • Horizontal
    • First choice- JR, usually 4
    • Second choice- AR
    • Third choice- AL (with backup from opposite aortic wall)
  • Upward looking
    • AL
    • Other choices- hockey stick, IMA guide, left venous bypass guide
    • (JR will not give enough backup)
  • Downward looking
    • AR
    • Multipurpose
    • Right venous bypass
    • (JR may dissect lateral wall)
  • Guide entering conus repeatedly
    • Engage by counterclockwise rotation
    • Change over to higher sized guide
  • Deep seating RCA guide
    • Do not do if artery is small or if there is a proximal plaque.
    • In LAO view, additional clockwise rotation will deep seat the guide
    • If balloon or stent is in the coronary, the guide may be deep seated with gentle clockwise rotation. After purpose is served, guide should be withdrawn with counterclockwise rotation.
    • When balloon or stent is advanced, assistant should hold the guide firmly near the femoral sheath
    • When balloon or stent is advanced, assistant should pull back wire slowly to decrease friction between wire and balloon/stent.
  • Rotational Amplatz maneuver
    • JR guide is pushed with counterclockwise rotation- it forms a loop resting in the coronary sinus- looks like Amplatz
    • Gives backup from opposite aortic wall
    • Excessive push may prolapse guide into LV
    • Do only with 6F or 5F- higher sized guides will prolapse into LV
    • Like any power position, do not do if there is ostial lesion
  • Guide for aortic aneurysm and dissections
    • Aortic aneurysm
      • Guide may not seat well
      • Guide may not be long enough
    • Aortic dissection
      • Guide may enter false lumen
      • Guide may extend dissection
      • Guide may perforate aortic wall, especially with injection
      • Guide may dislodge thrombus distally
    • If there is BP difference between arms, use radial route in arm with higher BP
    • If thoracoabdominal aorta is dissected or aneurismal, choose radial route
    • If arch vessels are affected, choose femoral route
    • If entire aorta is aneurismal, choose femoral route for better catheter manipulation
    • Straight soft tipped catheters like Sones or Multipurpose are safer
    • To make sure that catheter is in true lumen- enter LV or cannulate coronaries
    • Ascending aortogram- LAO view- 60 cc contrast at 25 to 40 cc/sec
    • Never do ascending aortogram unless it is absolutely certain that guide is in true lumen
      • No delay in contrast washout
      • No contrast swirling
      • No dampening of pressures
      • Brisk return of blood