Slow pathway modification in patients presenting with only two consecutive AV nodal echo beats

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Slow pathway modification (SPM) is the primary treatment for AV-nodal reentry tachycardia (AVNRT).
• The efficacy of SPM in patients with non-inducible AVNRT but two AV nodal echo beats (AVNEBs) remains unclear.
• Empirical ablation is sometimes considered when AVNRT is not inducible.

Purpose of the Study:

• To evaluate the procedural and long-term outcomes of SPM in patients experiencing symptomatic tachycardia without inducible AVNRT, but with two AVNEBs.
• To determine if SPM is a safe and effective treatment option in this specific patient subgroup.

Main Methods:

• Retrospective analysis of 32 patients who underwent SPM between 1993 and 2013, selected from a larger cohort of 3003 patients.
• Patients had symptomatic tachycardia, no inducible paroxysmal supraventricular tachycardia (pSVT), but exhibited two AVNEBs.
• Procedural success was defined as inducibility of less than two AVNEBs; long-term success was assessed via telephone questionnaire (63±9 months follow-up).

Main Results:

• The procedural endpoint (less than two AVNEBs) was achieved in 97% of patients (31 out of 32).
• Overall, 94% of patients benefited from SPM, with 59% achieving freedom from symptoms and 34% reporting improvement.
• Patients with prior ECG documentation of pSVT and those without showed similar positive outcomes (100% benefit in the latter group).

Conclusions:

• This study represents the first collective analysis of SPM outcomes in patients with two AVNEBs and non-inducible tachycardia.
• SPM demonstrated high procedural success and favorable long-term clinical outcomes, comparable to those for inducible AVNRT.
• Slow pathway modification is a safe and effective therapeutic strategy for patients presenting with symptoms of pSVT and two AVNEBs.