Lown-Ganong-Levine syndrome
In cardiology, Lown-Ganong-Levine syndrome is "a form of ventricular pre-excitation characterized by a short PR interval and a normal QRS complex. In this syndrome, the atrial impulse conducts via [a nonstandard pathway] which connect the atrium to bundle of bundle of His bypassing the upper atrioventricular node. Heart ventricles are depolarized normally through the His-Purkinje system."[1] It may not be diagnosed until well into adulthood, but it can produce bursts of dizziness or fainting through paroxysmal tachycardia. A broader term for conditions including the syndrome is enhanced atrioventricular nodal conduction, (EAVNC)Cite error: Invalid <ref> tag; refs with no name must have content, which defines a continuum containing "a set of functional criteria that includes an AH interval less than or equal to 60 ms, 1-to-1 AV nodal conduction at rates as high as 200 beats per minute, and an abnormally small increase in AH interval as atrial pacing rate is increased."[2]
A variety of supraventricular tachycardias can come from pathology where there is an abnormal conduction path, a normal one only, or both; the diagnosis may require invasive electrophysiological studies of the heart.[3] This has been reported in Wolff-Parkinson-White syndrome as well as Lown-Ganong-Levine. [4]
The pathological pathway may involve James fibers[5] Mahaim fibers,[6] Brechenmacher-type fibers,[7] and an anatomically underdeveloped (hypoplastic)[8] or small AV node.[9]
References
- ↑ Anonymous (2024), Lown-Ganong-Levine syndrome (English). Medical Subject Headings. U.S. National Library of Medicine.
- ↑ Jackman WM; Prystowsky EN; Naccarelli GV; Fineberg NS; Rahilly GT; Heger JJ; Zipes DP (1983), "Reevaluation of enhanced atrioventricular nodal conduction: evidence to suggest a continuum of normal atrioventricular nodal physiology.", Circulation 67 (2): 441-8
- ↑ Benditt DG et al. (August 1, 1979), "Ventriculoatrial Intervals: Diagnostic Use in Paroxysmal Supraventricular Tachycardia", Ann Internal Medicine 91 (2): 161-166
- ↑ D E Ward, A J Camm, and R A Spurrell (1978 October), "Re-entrant tachycardia using two bypass tracts and excluding AV node in short PR interval, normal QRS syndrome.", Br Heart J. 40 (10): 1127–1133
- ↑ Durrer D, Schuilenburg RM, Wellens HJ (1970 Jun), "Pre-excitation revisited", Am J Cardiol 25 (6): 690-7.
- ↑ Mahaim I. Kent fibers and the A-V paraspecific conduction through the upper connections of the bundle of His-Tawara. Am Heart J. 1947;33:651.
- ↑ Brechenmacher C, Laham J, Iris L, et al. [Histological study of abnormal conduction pathways in the Wolff-Parkinson-White syndrome and Lown-Ganong-Levine syndrome]. Arch Mal Coeur Vaiss. May 1974;67(5):507-19.
- ↑ Ometto R, Thiene G, Corrado D, et al. Enhanced A-V nodal conduction (Lown-Ganong-Levine syndrome) by congenitally hypoplastic A-V node. Eur Heart J. Nov 1992;13(11):1579-84.
- ↑ Benditt DG, Pritchett LC, Smith WM, et al. Characteristics of atrioventricular conduction and the spectrum of arrhythmias in Lown-Ganong-Levine syndrome. Circulation. Mar 1978;57(3):454-65.