Mahaim fiber tachycardias
- Philip J Podrid, MD, FACC
Philip J Podrid, MD, FACC
- Professor of Medicine, Professor of Pharmacology and Experimental Therapeutics
- Boston University School of Medicine
- Lecturer, Harvard Medical School
The term cardiac preexcitation was originally used to describe premature activation of the ventricles in patients with the Wolff-Parkinson-White (WPW) pattern. This term has been broadened to include all conditions in which antegrade ventricular activation or retrograde atrial activation occurs partially or totally via an anomalous pathway distinct from the normal cardiac conduction system.
The classic form of cardiac preexcitation is the WPW pattern, which is characterized by a short PR interval and a broad QRS complex with a delta wave. The anatomic substrate for this is a band of myocytes that bridges the fibrous atrioventricular junction, also known as the bundle of Kent . The electrocardiographic features are a result of premature ventricular activation due to conduction over the accessory pathway. (See "Anatomy, pathophysiology, and localization of accessory pathways in the preexcitation syndrome".)
Several other pathways, such as Mahaim fibers, have been postulated to result in cardiac preexcitation. However, most lack the histopathologic correlation that has been demonstrated for the WPW pattern. This topic will discuss the Mahaim fiber tachycardias. WPW and other non-WPW forms of preexcitation are discussed separately. (See "Epidemiology, clinical manifestations, and diagnosis of the Wolff-Parkinson-White syndrome" and "Lown-Ganong-Levine syndrome and enhanced atrioventricular nodal conduction".)
ANATOMIC AND FUNCTIONAL FEATURES
In 1937, during pathologic examination of the heart, Mahaim and Benatt identified islands of conducting tissue extending from the His bundle tissue into the ventricular myocardium . These fibers were termed Mahaim or fasciculoventricular fibers . This description was subsequently expanded to include connections between the atrioventricular (AV) node and the ventricular myocardium (nodoventricular fibers) (figure 1). These findings have been confirmed by other investigators, but true continuity of these pathways is less common than was initially suspected [1,3,4].
Mahaim fibers were originally classified into two main groups depending upon their site of origin :
- Anderson RH, Becker AE, Brechenmacher C, et al. Ventricular preexcitation. A proposed nomenclature for its substrates. Eur J Cardiol 1975; 3:27.
- Mahaim I, Benatt A. Nouvelles recherches sur les connections superieures de la branche du faisceau de His-Tawara avec cloison interventriculaire. Cardiologia 1937; 1:61.
- LEV M, LERNER R. The theory of Kent; a histologic study of the normal atrioventricular communications of the human heart. Circulation 1955; 12:176.
- JAMES TN. Morphology of the human atrioventricular node, with remarks pertinent to its electrophysiology. Am Heart J 1961; 62:756.
- Gallagher JJ, Smith WM, Kasell JH, et al. Role of Mahaim fibers in cardiac arrhythmias in man. Circulation 1981; 64:176.
- Tonkin AM, Dugan FA, Svenson RH, et al. Coexistence of functional Kent and Mahaim-type tracts in the pre-excitation syndrome. Demonstration by catheter techniques and epicardial mapping. Circulation 1975; 52:193.
- Ellenbogen KA, Ramirez NM, Packer DL, et al. Accessory nodoventricular (Mahaim) fibers: a clinical review. Pacing Clin Electrophysiol 1986; 9:868.
- Bardy GH, Fedor JM, German LD, et al. Surface electrocardiographic clues suggesting presence of a nodofascicular Mahaim fiber. J Am Coll Cardiol 1984; 3:1161.
- Tchou P, Lehmann MH, Jazayeri M, Akhtar M. Atriofascicular connection or a nodoventricular Mahaim fiber? Electrophysiologic elucidation of the pathway and associated reentrant circuit. Circulation 1988; 77:837.
- Klein GJ, Guiraudon GM, Kerr CR, et al. "Nodoventricular" accessory pathway: evidence for a distinct accessory atrioventricular pathway with atrioventricular node-like properties. J Am Coll Cardiol 1988; 11:1035.
- Murdock C, Klein GJ, Guiraudon GM, et al. Epicardial mapping in patients with nodoventricular electrophysiologic pattern. Circulation 1990; 82(Suppl III):III-472.
- Gillette PC, Garson A Jr, Cooley DA, McNamara DG. Prolonged and decremental antegrade conduction properties in right anterior accessory connections: Wide QRS antidromic tachycardia of left bundle branch block pattern without Wolff-Parkinson-White configuration in sinus rhythm. Am Heart J 1982; 103:66.
- Klein LS, Hackett FK, Zipes DP, Miles WM. Radiofrequency catheter ablation of Mahaim fibers at the tricuspid annulus. Circulation 1993; 87:738.
- Haïssaguerre M, Cauchemez B, Marcus F, et al. Characteristics of the ventricular insertion sites of accessory pathways with anterograde decremental conduction properties. Circulation 1995; 91:1077.
- Jongbloed MR, Wijffels MC, Schalij MJ, et al. Development of the right ventricular inflow tract and moderator band: a possible morphological and functional explanation for Mahaim tachycardia. Circ Res 2005; 96:776.
- Abbott JA, Scheinman MM, Morady F, et al. Coexistent Mahaim and Kent accessory connections: diagnostic and therapeutic implications. J Am Coll Cardiol 1987; 10:364.
- Sung RJ, Styperek JL. Electrophysiologic identification of dual atrioventricular nodal pathway conduction in patients with reciprocating tachycardia using anomalous bypass tracts. Circulation 1979; 60:1464.
- Hamdan MH, Kalman JM, Lesh MD, et al. Narrow complex tachycardia with VA block: diagnostic and therapeutic implications. Pacing Clin Electrophysiol 1998; 21:1196.
- Sternick EB, Timmermans C, Sosa E, et al. The electrocardiogram during sinus rhythm and tachycardia in patients with Mahaim fibers: the importance of an "rS" pattern in lead III. J Am Coll Cardiol 2004; 44:1626.
- Okishige K, Strickberger SA, Walsh EP, et al. Catheter ablation of the atrial origin of a decrementally conducting atriofascicular accessory pathway by radiofrequency current. J Cardiovasc Electrophysiol 1991; 2:465.
- McClelland JH, Wang X, Beckman KJ, et al. Radiofrequency catheter ablation of right atriofascicular (Mahaim) accessory pathways guided by accessory pathway activation potentials. Circulation 1994; 89:2655.
- Heald SC, Davies DW, Ward DE, et al. Radiofrequency catheter ablation of Mahaim tachycardia by targeting Mahaim potentials at the tricuspid annulus. Br Heart J 1995; 73:250.
- Brugada J, Martínez-Sánchez J, Kuzmicic B, et al. Radiofrequency catheter ablation of atriofascicular accessory pathways guided by discrete electrical potentials recorded at the tricuspid annulus. Pacing Clin Electrophysiol 1995; 18:1388.
- Haissaguerre M, Warin JF, Le Metayer P, et al. Catheter ablation of Mahaim fibers with preservation of atrioventricular nodal conduction. Circulation 1990; 82:418.
- Bardy GH, German LD, Packer DL, et al. Mechanism of tachycardia using a nodofascicular Mahaim fiber. Am J Cardiol 1984; 54:1140.
- Ellenbogen KA, Rogers R, Old W. Pharmacological characterization of conduction over a Mahaim fiber: evidence for adenosine sensitive conduction. Pacing Clin Electrophysiol 1989; 12:1396.
- Strasberg B, Coelho A, Palileo E, et al. Pharmacological observations in patients with nodoventricular pathways. Br Heart J 1984; 51:84.
- Bhandari A, Morady F, Shen EN, et al. Catheter-induced His bundle ablation in a patient with reentrant tachycardia associated with a nodoventricular tract. J Am Coll Cardiol 1984; 4:611.
- Ellenbogen KA, O'Callaghan WG, Colavita PG, et al. Catheter atrioventricular junction ablation for recurrent supraventricular tachycardia with nodoventricular fibers. Am J Cardiol 1985; 55:1227.