Use of Electrogram Characteristics During Sinus Rhythm to Delineate the Endocardial Scar in a Porcine Model of Healed Myocardial Infarction

摘要: Introduction: Substrate-based catheter ablation of postmyocardial infarction (post-MI) ventricular tachycardia necessitates electroanatomic definition the scarred endocardium. We sought to determine whether electrogram criteria during sinus rhythm could identify location and extent myocardial scar by mapping. Methods Results: A porcine model healed MI was generated injecting agarose microspheres into mid left anterior descending coronary artery. At least 4 weeks post-MI, animals(n = 24)underwent detailed endocardial mapping using a 4-mm-tip (BioSense-Webster, Inc.). Based upon data in normal animals, infarcted tissue defined as bipolar amplitude <1.5 mV duration ≥50 msec. Radiofrequency lesions (2–10 per animal) were placed tag borders mapping-defined scar. The area abnormal voltage was25.9 ± 15.4 cm2(range 6.9–60.5). This correlated well with that criteria(26.4 16 cm2). Of those points remote from infarct falsely low resulting presumed poor catheter-tissue contact, 94% correctly identified when criteria. Late potentials observed predominantly along myocardium. radiofrequency located periphery gross pathologic examination. Conclusion: During rhythm, both are able help differentiate tissue. Using these criteria, reconstruction can be rendered heart.(J Cardiovasc Electrophysiol, Vol. 14, pp. 524-529, May 2003)