What is the recommended technique for interatrial septal puncture?

Recommended Technique for Interatrial Septal Puncture

The most common and recommended technique for interatrial septal puncture is using the Brockenbrough transseptal needle in conjunction with Mullins long transseptal sheath/dilator sets under biplane fluoroscopy guidance. 1

Standard Transseptal Puncture Technique

Equipment Requirements

• Brockenbrough transseptal needle 1
• Mullins long transseptal sheath/dilator sets (Medtronic or Cook Medical) 1
• Biplane fluoroscopy system 1

Procedural Steps

1. Imaging Setup: Biplane fluoroscopy is essential for safe and dependable performance of transseptal puncture, particularly in small patients 1

   • Biplane fluoroscopy allows constant 3-dimensional mental reconstruction of intracardiac structures 1
   • Single-plane fluoroscopy should only be used under extenuating circumstances and by highly experienced operators 1

2. Equipment Preparation:

   • The Mullins dilator fits tightly over the Brockenbrough needle with precise tolerances 1
   • The long, thin-walled sheath fits tightly over the dilator 1
   • These tight tolerances allow the sheath/dilator combinations to pass through the septum with minimal force after needle puncture 1

3. Puncture Technique:

   • Position the needle and sheath/dilator at the fossa ovalis 1
   • Use biplane fluoroscopy to ensure proper positioning 1
   • Advance the Brockenbrough needle to puncture the septum 1
   • Advance the dilator and sheath over the needle into the left atrium 1
   • Remove the needle and dilator, leaving the sheath for access 1

Alternative Technique: Radiofrequency Transseptal Perforation

Indications for Radiofrequency Approach

• Very small patients with small left atria (e.g., newborns with hypoplastic left heart) 1
• When there is no direct femoral approach 1
• When a needle cannot be pushed forcefully through the atrial septum 1
• When access from jugular vein is required 1

Radiofrequency Technique

• Uses a special radiofrequency generator (different from electrophysiological RF ablation) 1
• Energy parameters: low-power (5 W), high-intensity (150-180 V) electric current 1
• Administration time: very short (0.4 second) 1
• Electrode size: very tiny-diameter (1.3F) 1
• Requires no "force" to accomplish perforation 1
• After perforation, a fine coaxial catheter is advanced over the RF wire 1
• The RF wire is exchanged for stiffer and more supportive wire 1
• A fine-tipped dilator or Mullins sheath is introduced into the left atrium 1

Adjunctive Imaging Techniques

• Transesophageal Echocardiography (TEE): Improves precision in transseptal puncture compared to fluoroscopy alone 2

  • TEE-guided TSP achieves optimal positioning in 59.3% of cases versus 32.7% with fluoroscopy alone 2
  • Eliminates poor or dangerous needle positions 2

• Other Adjuncts: Various types of simultaneous echocardiograms, special angled views, and marker catheters in the aorta can be used but are not equal substitutes for biplane fluoroscopy 1

Special Considerations and Cautions

Contraindications for Single-Plane Fluoroscopy

• Very small patients 1
• Patients with very large or very small left atrium 1
• Patients with large dilated aortic root 1
• No inferior vena cava access to the atrial septum 1
• Presence of abnormal cardiac chamber or great vessel positional abnormalities 1

Potential Complications

• Cardiac perforation (especially with small left atrial volume) 1
• Entry into the aorta 1
• Air embolization associated with catheter and needle exchanges 1

Challenging Cases

• For difficult transseptal punctures with severe septal tenting, a nitinol guidewire ("needle wire") can be used 3
• For puncture through previously placed septal occluder devices, specialized techniques with intraprocedural imaging are required 4
• In cases where conventional approaches fail, angioplasty wires may assist in perforation 5

Indications for Transseptal Puncture (Class I)

1. For transcatheter interventions optimally performed from left atrial approach 1
2. For hemodynamic assessment of suspected left ventricular outflow tract obstruction when retrograde crossing of the aortic valve is difficult 1
3. For hemodynamic assessment of significant mitral valve stenosis 1
4. When entry to the left atrium is necessary for electrophysiological study or therapy 1