Fetoscopic Transesophageal Electrocardiography and Stimulation in Fetal Sheep

Abstract

Background-Therapy-refractory supraventricular tachycardia commonly results in hydrops and death in human fetuses.The purpose of this study in fetal sheep was to assess the feasibility of a minimally invasive fetoscopic approach for fetal transesophageal electrocardiography and stimulation aimed at diagnosis and termination of these tachycardias. Methods and Results -We studied a total of 10 fetal sheep (87 to 103 days of gestation; termϭ145 days). We entered the amniotic cavity using a percutaneous fetoscopic approach and placed various electrophysiology catheters into the fetal esophagus. We recorded the number of animals in which fetoscopic transesophageal electrocardiography and stimulation were successful and assessed pacing success and thresholds for different catheters. In addition, we monitored for potential adverse effects from stimulation and for other complications of the operation. Recording of transesophageal electrocardiograms was successful in all fetal sheep. Capture during stimulation was successfully documented by additional fetal bipolar surface electrocardiograms in 7 fetuses. In fetuses in which fetal surface electrocardiograms were not recorded, pacing stimulus artifacts interfered with documentation of capture. Although stimulation thresholds were high, the maternal rhythm was not affected by fetal stimulation. Conclusions-Fetoscopic

Impact of Intrauterine Balloon Aortic Valvuloplasty on Gestational Outcome in a Fetal Goat Model

“…Long-term impact of IUBAV on gestational outcome and on the fetus (preterm delivery in 6 of 10 newborns, 60%) man fetuses in previous studies [17,28,29] . White et al [28] thought that fetuses of the middle/later gestational age may have developed the pain sensation and response to stimulus.…”

“…Preterm delivery of 60% was recorded in the IUBAV group. This did not occur in goats that received only anesthesia and laparotomy, suggesting that a procedure before fetal intervention was not the cause of preterm delivery, but that this may instead ultimately be caused by factors that disrupt the integrity of the uterus and amniotic cavity [17,[23][24][25][26] . The leakage of amniotic fluid was frequently observed in noncardiac fetal surgery, which is usually associated with the underdevelopment of lungs and complications relating to compression of the umbilical cord.…”

“…Intrauterine intervention for certain congenital heart defects, such as obstruction, may prevent the progression of the severity of the primary lesions and subsequent underdevelopment of secondary lesions [7][8][9][10][11][12] . Although technical feasibility has been achieved in both animal models and clinical patients [13][14][15][16][17] , the selection of the most appropriate patients for consider-…”

Protective effects of indomethacin and dexamethasone in a goat model with intrauterine balloon aortic valvuloplasty

“…Although the technical feasibility has been achieved in animal models as well as in clinical patients [13,25-28], the selection of the right patients in consideration of the long-term outcome of the fetus is still controversial. Our recent study [15] indicated that the IUBAV operation itself causes significant stress responses in fetuses of a goat model, which may in turn disrupt the normal course of gestation.…”