Cryoablation at Growing Myocardium: No Evidence of Coronary Artery Obstruction or Intimal Plaque Formation Early and Late after Energy Application

Abstract

By means of the present study, we did not observe any affection of the coronary arteries after cryoenergy application at growing myocardium in young piglets.

Double Cryoenergy Application (Freeze‐Thaw‐Freeze) at Growing Myocardium: Lesion Volume and Effects on Coronary Arteries Early After Energy Application. Implications for Efficacy and Safety in Pediatric Patients

“…In contrast, in a previous study of our group using the same piglet model, single cryoenergy application had not resulted in coronary artery wall changes as documented by angiography, ICUS and histology . It is of note, however, that after RFA in the same animal model, leukocyte infiltration of the layers of the RCA was found in 3/5 animals studied at the same time …”

“…Cryothermy has emerged as an alternative energy source with an improved safety profile for treatment of SVT in children. As of yet, neither persistent complete atrioventricular (AV) block nor significant coronary artery obstruction have been reported clinically or in animal models . The relatively smaller experience with cryoablation may be an important reason that rare adverse events have not been identified to date.…”

“…The purpose of our study was to use a previously established piglet model to assess lesion volume (efficacy) and risk of coronary artery damage (safety) early, i.e., 48 hours, after a modified double cryoenergy application as a freeze‐thaw‐freeze cycle at the AV groove. As a comparative group, data from a previous study from our institution applying a single freeze‐thaw cycle in a pig model as well as data from the same pig model applying RFA were used …”

Don't Forget to Gather the Evidence

“…This finding, which was also confirmed by Kriebel et al, 12 can provide some comfort to the physician, since most ablations at every age are performed for AV groove related substrates (71% in infants and 89% in children). 13 Saul et al 2 suggested that transmurality of the lesions may have been a factor in lesion expansion.…”

“…However, 2 prior studies did demonstrate that CRYO can have minimal effects on nearby coronary arteries of infant pigs, with increased mural echogenicity by intracoronary ultrasound in 1 of 5 animals, and some lesion extension into the medial coronary wall of the left circumflex, without stenosis or flow abnormalities. 12,14,15 These changes were far less than those observed with RF lesions in prior studies. 16 …”