Author + information
- Received May 25, 1988
- Revision received August 24, 1988
- Accepted September 6, 1988
- Published online March 15, 1989.
- Norberto Schechtmann, MD, FACC1,2,
- Elias H. Botvinick, MD, FACC∗,1,2,
- Michael Dae, MD1,2,
- Melvin M. Scheinman, MD, FACC1,2,
- J. William O'Connell, BS1,2,
- Jesse Davis, MD, FACC1,2,
- Stuart Winston, OD1,2,
- Allan Schwartz, MD, FACC1,2 and
- Joseph Abbott, MD, FACC1,2
- ↵∗Address for reprints: Elias H. Botvinick, MD, Box 0214, M-1186, University of California at San Francisco, San Francisco, California 94143.
The phase image pattern of blood pool scintigrams was blindly assessed in 11 patients exhibiting conduction through Mahaim pathways, including 6 nodoventricular and 5 fasciculoventricular. These patterns were compared with the phase image findings in normal subjects, patients with left and right bundle branch block in the absence of pre-excitation and patients with pre-excitation through atrioventricular (AV) connections.
In all patients with a Mahaim pathway, the site of earliest phase angle was septal or paraseptal. Phase progression was asymmetric and the pre-excited ventricle demonstrated the earliest mean ventricular phase angle in 10 of 11 patients. This pattern, and the associated ventricular phase difference, appeared to vary from that in normal subjects and in those with a septal AV connection, in whom phase progression is generally symmetric.
Scintigraphic phase analysis provided localizing information and presented patterns consistent with Mahaim pathways. Although not able to differentiate among Mahaim pathway subtypes, these phase patterns differed from those in normal subjects, those with right and left lateral free wall pathways and most patients with a septal AV pathway. However, the phase pattern of patients with a Mahaim pathway may not differ from that of patients with a septal AV connection displaying an asymmetric pattern of phase progression, or those with left and right bundle branch block in the absence of pre-excitation. Objective, yet imperfect phase measurements supported these differences. Such image findings may complement the often complex electrophysiologic evaluation of patients presenting with pre-excitation.
☆ This work was supported in part by a grant from the Fannie Rippel Foundation, Madison, New Jersey. Dr. Schechtmann, Attending Cardiologist at Ramos Mejia Hospital, Buenos Aires, Argentina, performed this work while he was a postdoctoral fellow at the University of California, San Francisco. Dr. Botvinick participated in this study while an Established Investigator of the American Heart Association with funds contributed by local heart associations. He is supported in part by a grant from the George D. Smith Fund, San Francisco. Dr. Winston performed this work while he was a postdoctoral fellow at the University of California, San Francisco.
- Received May 25, 1988.
- Revision received August 24, 1988.
- Accepted September 6, 1988.