Transvenous pacing

Indications

• Faiure of transcutaneous pacing + chronotropes
  • Sinus Arrest/Bradycardia
  • AV Block - 3rd or 2nd degree. May occur from MI, bacterial endocarditis, or Lyme dz
  • Drug OD - Digoxin toxicity
  • Overdrive pacing

Contraindications

• Asystolic cardiac arrest
• Hypothermia bradydysrhythmias

Procedure

1. Site selection: Right IJ or left subclavian for most smooth anatomical course
2. Equipment:
   1. External generator: Shows rate (bpm), output (mA) and sensitivity
   2. Cordis Kit (7 Fr): Gold strip on kit at Harbor. Contains cordis introducer sheath, TV pacer catheter and pacer wire sheath
      1. Sheath size (internal diameter) should match pacer wire size (external diameter). Otherwise you will get leakage!
3. Similar to a central line, place single lumen catheter under ultrasound guidance.
4. Pacing catheter
   1. Test small balloon for leaks prior to insertion with 1.5mL of air while balloon rests in a container of saline
   2. Connect the positive and negative electrodes to the external generator
   3. Advance the catheter through the introducer sheath and into cordis hub to roughly 20 cm (catheter has marked bars indicating 10cm)
5. External generator: Set HR 80, start at max current output (usually 20 mA), and sensitivity all the way down (paces no matter intrinsic rate)
   1. Pearl - Digital generators have "emergency" button that goes to automatic settings
6. Advancing Pacing Catheter: Inflate ballon and advance slowly.
   1. Blind approach: Monitor shows pacer spikes followed by a widened QRS (LBBB appearance)
   2. Ultrasound approach: Have assistant give a subcostal/parasternal long axis, which gives visualization image of when electrode contacts final resting position
   3. Sensing approach: Use alligator clip to connect negative pacer electrode to any precordial lead. Look for ST elevation when RV endocardium engaged.
   4. Fluoroscopy: If time permits, use this method in a patient that has prior pacemaker/AICD. Placement of TV pacer w/o fluoro can disrupt prior electrode placements.
7. Final resting position is when pacer wire is in RV apex
   1. Take note of pacer wire depth in case it's accidentally moved
   2. If you overshot your mark (ie IVC/Pulm artery), deflate balloon and pull back. YOU DO NOT WANT TO PULL INFLATED BALLOON THROUGH A VALVE.
   3. Pearl - IVC pacing leads to coughing/hiccuping and ventilator alarms (ie high frequency)
8. Deflate balloon (leave syringe attached) and secure catheter in place
   1. Lock sheath onto cordis hub and then fully extend it & curl around while holding pacer wire in place. Sheath gives sterile amount of wire for any future adjustments if needed.
   2. Additional sutures can be placed to stabilize it
9. Final Settings
   1. Output: Determine threshold level by reducing electrical current settings until capture lost. Final current set to twice the threshold level for pt
   2. Sensitivity: Adjust level (not too high or too low) so it allows intrinsic beats, but supplements it if needed. You do not want oversensing or undersensing.
10. Placement confirmation
    1. Good to obtain baseline CXR, which should show the catheter tip over the inferior border of the cardiac shadow
    2. EKG shows paced QRS exhibiting a LBBB morphology, and a superior QRS axis

Complications

• Related to central venous access
  • Infection, PTX, air embolism, arterial puncture and venous thrombosis
• Related to pacing catheter:
  • Valvular tear(s)/rupture(s)
  • Myocardial Peforation (atria/ventricle/septum) - consider tamponade
• Ventricular Arrhythmias: VT or VF

Links

• University of Cincinnati
  • Part 1: Walkthrough
  • Part 2: Procedural Slide Set
  • Part 3: Video
• Drexel Video
• Practical Pointers

See Also

• ACLS: Bradycardia
• Transcutanous pacing