JACC Vol. 5, No.6 1261 June 1985:1261-75

COOPERATIVE STUDIES

Criteria for Intraventricular Conduction Disturbances and Pre-excitation

JOS L. WILLEMS, MD,* ETIENNE O. ROBLES DE MEDINA, MD, FACC,t ROLAND BERNARD, MD,t PHILIPPE COUMEL, MD,§ CHARLES FISCH, MD, FACC,II DENNIS KRIKLER, MD, FACC,** NICOLAI A. MAZUR, MD,tt FRITS L. MEHLER, MD, FACC (Chairman),t LARS MOGENSEN, MD,:j::j: PIERRE MORET, MD, FACC,§§ ZBYNEK PISA, MD,IIII PENTTI M. RAUTAHARJU, MD,*** BORYS SURAWICZ, MD, FACcl1 YOSHIO WATANABE, MD, FACC,ttt HEIN J. J. WELLENS, MD, FACCt:j::j: World Health Organization/International Society and Federation for Task Force Ad Hoc

In an etTortto standardize terminology and criteria for and left posterior fascicular block, nonspecific intra­ clinical , and as a follow-up of its ventricular block, WoltT-Parkinson-White syndrome and work on definitions of terms related to cardiac rhythm, related pre-excitation patterns. Criteria for intraatrial an Ad Hoc Working Group established by the World conduction disturbances are also briefly reviewed. Health Organization and the International Society and The criteria are described in clinical terms. A concise Federation of Cardiology reviewed criteria for the di­ description of the criteria using formal Boolean logic is agnosis of conduction disturbances and pre-excitation. given in the Appendix. For the incorporation into com­ Recommendations resulting from these discussions are puter electrocardiographic analysis programs, the limits summarized for the diagnosis of complete and incom­ of some interval measurements may need to be adjusted. plete right and left , left anterior (J Am Coll CardioI1985,'5:1261-75)

In recent years at international meetings and through con­ nication between the interpreter and the user. Since other certed actions, several investigators (1-6) have made an groups specifically have addressed the problems of stand­ appeal for standard rules of measurement, classification and ardization of terminology (1-2) and measurement (5-6), description for electrocardiographic features. Such stan­ the present Task Force was established to examine the pos­ dards are desirable to improve patient care and disseminate sibility of standardization of diagnostic classification criteria. medical knowledge and experience. Patient care can be im­ At the 10th Bethesda Conference on Optimal Electro­ proved by enhancing the consistency and quality of the cardiography (1), it was proposed to categorize diagnostic electrocardiographic report and, thus, facilitating commu- electrocardiographic statements into three categories (Table I): From the *University of Leuven, Leuven, Belgium; tUniversity of I) Type A statements refer to an anatomic lesion or patho­ Utrecht, Utrecht, The Netherlands; :j:Universityof Brussels, Brussels, Bel­ gium; §University of Paris, Paris, France; [Krannert Institute of Cardiol­ physiologic state, such as hypertrophy, infarction, , ogy, Indiana University, Indianapolis, Indiana; **University of London, pulmonary disease, drug and metabolic effects, and which London, England; ttNational Cardiology Research Centre, Moscow, can be verified by nonelectrocardiographic evidence; U.S.S.R.; :j::j:Karolinska Sjukhuset, Stockholm, Sweden; §§University of Geneva, Geneva, Switzerland; II11Worid Health Organization, Geneva, 2) Type B statements refer to an anatomic or functional Switzerland; ***Dalhousie University, Halifax, Canada; tttFujita Gakuen disturbance, such as and conduction defects, University, Nagoya, Japan; :j::j::j:University of Limburg, Maastricht, The and which are detectable mainly by the electrocardiogram Netherlands. This study was supported by grants from the World Health Organization (Geneva), the European Commissi