Transvenous pacing

Indications

Contraindications

Procedure

File:Transvenous ECG.jpg
Pacing by location
  1. Site selection: Right IJ or left subclavian for most smooth anatomical course
  2. Equipment:
    • External generator: Shows rate (bpm), output (mA) and sensitivity
    • Cordis Kit (7 Fr): Gold strip on kit at Harbor. Contains cordis introducer sheath, TV pacer catheter and pacer wire sheath
      • 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
    • Test small balloon for leaks prior to insertion with 1.5mL of air while balloon rests in a container of saline
    • Connect the positive and negative electrodes to the external generator
    • 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)
    • Pearl - Digital generators have "emergency" button that goes to automatic settings
  6. Advancing Pacing Catheter: Inflate balloon and advance slowly.
    • Blind approach: Monitor shows pacer spikes followed by a widened QRS (LBBB appearance)
    • Ultrasound approach: Have assistant give a subcostal/parasternal long axis, which gives visualization image of when electrode contacts final resting position
    • Sensing approach: Use alligator clip to connect negative pacer electrode to any precordial lead. Look for ST elevation when RV endocardium engaged.
    • Fluoroscopy: If time permits, use this method in a patient that has prior pacemaker/ICD. Placement of TV pacer with out fluoro can disrupt prior electrode placements.
  7. Final resting position is when pacer wire is in RV apex
    • Take note of pacer wire depth in case it is accidentally moved
    • 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.
    • Pearl - IVC pacing leads to coughing/hiccuping and ventilator alarms (ie high frequency)
  8. Deflate balloon (leave syringe attached) and secure catheter in place
    • 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.
    • Additional sutures can be placed to stabilize it
  9. Final Settings
    • Output: Determine threshold level by reducing electrical current settings until capture lost. Final current set to twice the threshold level for pt
    • 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
    • Good to obtain baseline CXR, which should show the catheter tip over the inferior border of the cardiac shadow
    • ECG shows paced QRS exhibiting a LBBB morphology, and a superior QRS axis

Complications

  • Related to central venous access
    • Infection, pneumothorax, 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

See Also