Arrhythmias & electrophysiology
Endo-epicardial mapping of human sinus node in vivo: Novel electrophysiologic findings and anatomic correlations
Authors' conclusion
The earliest SAN-EZ was found in the epicardium. Bipolar EGM reversed polarity is a novel electrophysiologic marker for SAN-EZs.
Study context
- Population
- Patients with symptomatic IST, refractory to or intolerant of drugs, undergoing endocardial and epicardial mapping of sinoatrial node (SAN) during hybrid ablationpatients included
- Participants
- 61 patients
- Comparison
- Epicardial vs endocardial SAN-EZ activation
- Outcome
- SAN-EZ area
Methodological detailsAll consecutive patients, hybrid SAN-sparing IST ablation
- All consecutive patients
- Hybrid SAN-sparing IST ablation
Main finding
As reported in the abstract
SAN-EZ area
1.4 ± 0.6 cm²
Further findings
ms
| Outcome | Epicardial SAN-EZ | Endocardial SAN-EZ | P value |
|---|---|---|---|
| Local activation time of SAN-EZ | −30.8 | −12.4 | P < 0.001 |
SAN-EZ location
Patients
- Superior anterior region of the right atrium (RA)
- 46 (75.4%)
- Mid RA
- 15 (24.6%)
Site of earliest activation
- The earliest activation occurred on epicardial SAN-EZ in all patients
Endo-epicardial delay
- Endo-epicardial delay
- 19.7 ms
Bipolar electrogram (EGM) reversed polarity at SAN-EZs
- Bipolar EGM reversed polarity at SAN-EZs
- 43 (70.5%) patients
Superior vena cava (SVC) sleeve extension
- SVC sleeve extension
- 31.2 mm
- Inversely correlated with age
Original publication
Endo-epicardial mapping of human sinus node in vivo: Novel electrophysiologic findings and anatomic correlations. Heart Rhythm. Published 20 March 2025. doi:10.
Summarised from the published abstract; every number is checked against it