• Research & Clinical Studies

    CardioCommand Systems provide easy access to all the diagnostic benefits of the Esophageal ECG

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    CardioCommand Systems provide easy access to all the diagnostic benefits of the Esophageal ECG.

    The close proximity of the esophageal electrodes to the posterior atrium and left ventricle provides greater signal strength, resulting in larger P-waves (atrial activation) as well as an amplified QRS complex (ventricular activity). Because the atrium is positioned behind the ventricles relative to the chestwall, P-waves are often obscured by ventricular electrical activity in ECG recordings acquired from surface electrodes. Thus esophageal ECG monitoring is essential for accurate diagnosis of cardiac arrhythmias for which a clearly identifiable P-wave is needed.

    "Ambulatory esophageal EKG monitoring is feasible and when compared to QRST subtraction can reveal left atrial foci as initiators of paroxysmal atrial fibrillation (AF). Documentation of early esophageal lead activation for left atrial premature beats that initiate AF is highly predictive of pulmonary vein triggers, and may serve as a useful screening test for candidates for focal AF ablation."  Guerra P, et al. NASPE, 1999. Abstract 

    "The capsule with enclosed electrodes was voluntarily swallowed, and the recording electrodes were positioned posterior to the left atrium. A high-quality esophageal electrocardiographic recording was obtained within one to 10 minutes with minimal patient discomfort. In 25 of 48 study patients (52%), the original diagnosis, based on the surface electrocardiographic recording, was incorrect after review of the esophageal recording. Results of esophageal recording altered management in 19 of 48 (40%) patients." Shaw M, et al. Am J Med 82(4):689-96, 1987. Abstract

    " The esophageal lead is safe, simple to use, and provides valuable information for detection or diagnosis of dysrhythmias and myocardial ischemia during anesthesia."
    Kates RA, et al. Anesth Analg 61(9):781-5, 1982. Abstract

    "Atrial flutter may be difficult to diagnose in infants with tachycardia unless transesophageal electrogram recording is utilized for evaluation."
    Dunnigan A, et al. Pediatrics 75(4):725-729, 1985. Abstract  Example

    "Twenty-six of 68 (pediatric cardiac surgery) patients exhibited rhythms during reperfusion that required the Esophageal ECG for definitive diagnosis." Bushman GA. J Cardiothor Anesth 3(3):290-4, 1989. Abstract

    "Heart rate variability (HRV) analysis has been an established method for assessment of the activities of autonomic nervous system. A-A intervals in the intraatrial ECG and P-P intervals in surface ECG were poorly correlated (r = 0.489) in AV block patients. However, intraatrial ECG was well correlated with esophageal ECG (r = 0.968). HRV with time domain decreased significantly in patients with AV block. The esophageal lead recording is a non-invasive, easy and safe method to detect HRV of AV block patients whose vagal activity is abnormal."
    Hsiao HC, et al. Chung Hua I Hsueh Tsa Chih (Taipei) 60(2):81-5, 1997. Abstract

    "Risk stratification of postmyocardial infarction patients ... suggests that heart rate variability is the single most important predictor of those patients who are at high risk of sudden death or serious ventricular arrhythmias." Malik M, Camm AJ. Clin Cardiol 13, 570-576, 1990. Abstract

    "This new high-resolution Esophageal-ECG device detected in a beat-to-beat technique more atrial activity during cardioplegic arrest than a Surface-ECG and offered the advantages of artifact exclusion and better prediction of postoperative supraventricular dysrhythmias."
    Maechler HE, et al. Anesth Analg 84(3):484-90, 1997. Abstract

    "During acute myocardial ischemia and infarction in sheep, the esophageal electrocardiograph has visually apparent ST alternans of amplitude in the millivolt range ... This is therefore one very promising technique for better evaluation of electrocardiographic changes of ischemia."
    Machler HE, et al. Anesth Analg 86(1):34-9,1998. Abstract

    "The precession of the left atrial electrogram recorded by the esophageal electrode on the P wave in lead V1 during supraventricular tachycardia (SVT) was a specific criterion of reentry through a left accessory AV connection, and this technique could be useful for preliminary localization of the accessory connection before electrophysiologic study." Brembilla-Perrot B. Am Heart J 121(6 Pt 1):1714-20, 1991. Abstract

    "Esophageal recording during reciprocating tachycardia provides a simple screening procedure available to all practicing physicians to exclude the diagnosis of accessory atrioventricular pathways in the genesis of paroxysmal supraventricular tachycardia".
    Gallagher JJ, et al. PACE 3(4): 440-51, 1980. Abstract

    "In esophageal electrophysiologic studies, electrographic V-A interval exceeding 90 ms during an attack of tachycardia is a major sign of reciprocal atrioventricular tachycardia due to additional atrioventricular junctions."
    Sulimov VA, et al. Kardiologiia 28(2):11-17, 1988.  Abstract

    "Esophageal ECG can be monitored continuously in order to characterize transient, self-limiting tachycardias. Monitoring has been performed for up to four days without problems."
    Bagger H. Ugeskr Laeger 153(47):3321-2, 1988.  Abstract