title: Second-degree atrioventricular block and the haystack principle.
authors.affiliation: Cardiology Division, University of Massachusetts Medical School, Worcester, MA 01655, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Spodick
mesh_terms: D000368:Aged; D003327:Coronary Disease / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006327:Heart Block / Q000503:physiopathology*; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans