Sanchez Javier E, Kay G Neal, Benser Michael E, Hall Jeffrey A, Walcott Gregory P, Smith William M, Ideker Raymond E
Department of Internal Medicine, Division of Cardiovascular Diseases, Cardiac Rhythm Management Laboratory, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
J Interv Card Electrophysiol. 2003 Feb;8(1):9-17. doi: 10.1023/a:1022315308803.
Determining whether a linear catheter radio frequency (RF) ablation lesion is transmural may be difficult, especially during atrial fibrillation. We hypothesized that changes in pacing thresholds and electrogram amplitude during atrial fibrillation and sinus rhythm could be used to assess whether a radiofrequency ablation resulted in transmural necrosis.
A hexapolar, linear, RF ablation catheter was positioned between the caval veins in the right atrium of seven sheep. Pacing thresholds and electrogram amplitudes during atrial fibrillation and sinus rhythm were measured before and after the application of RF energy. Sites along the linear lesion were assessed histologically.
The electrogram amplitude in atrial fibrillation decreased significantly more at transmural sites (unipolar recording: 33 +/- 11% transmural vs. 22 +/- 13% non-transmural, p < or = 0.01; bipolar recording: 62 +/- 9% transmural vs. 43 +/- 15% non-transmural, p < or = 0.01). The electrogram amplitude in sinus rhythm decreased significantly more at transmural sites (unipolar recording: 49 +/- 18% transmural vs. 15 +/- 20% non-transmural, p < 0.001; bipolar recording: 63 +/- 17% transmural vs. 42 +/- 19% non-transmural, p = 0.002). The pacing threshold increased significantly more at sites with transmural necrosis (unipolar: increased by 378 +/- 103% transmural vs. 207 +/- 93% non-transmural, p < 0.001; bipolar: 370 +/- 80% transmural vs. 259 +/- 60% non-transmural, p < 0.001).
The amplitude of the atrial electrogram from an ablation catheter can be used to discriminate areas with transmural necrosis from those without transmural necrosis during either atrial fibrillation or sinus rhythm. Termination of atrial fibrillation may not be necessary to estimate the histologic characteristics of an ablation lesion.
确定线性导管射频（RF）消融损伤是否透壁可能具有挑战性，尤其是在房颤期间。我们推测，房颤和窦性心律期间起搏阈值和电图幅度的变化可用于评估射频消融是否导致透壁坏死。
将一根六极线性射频消融导管置于7只绵羊右心房的腔静脉之间。在施加射频能量前后，测量房颤和窦性心律期间的起搏阈值和电图幅度。对线性损伤部位进行组织学评估。
在透壁部位，房颤时电图幅度下降更为显著（单极记录：透壁部位为33±11%，非透壁部位为22±13%，p≤0.01；双极记录：透壁部位为62±9%，非透壁部位为43±15%，p≤0.01）。在窦性心律时，透壁部位电图幅度下降更为显著（单极记录：透壁部位为49±18%，非透壁部位为15±20%，p<0.001；双极记录：透壁部位为63±17%，非透壁部位为42±19%，p = 0.002）。在有透壁坏死的部位，起搏阈值升高更为显著（单极：透壁部位升高378±103%，非透壁部位升高207±93%，p<0.001；双极：透壁部位为370±80%，非透壁部位为259±60%，p<0.001）。
在房颤或窦性心律期间，消融导管记录的心房电图幅度可用于区分有透壁坏死和无透壁坏死的区域。估计消融损伤的组织学特征不一定需要终止房颤。
