title: Graphical representation of complex data--diurnal patterns of initiations of atrial fibrillation episodes.
abstract: A construction of a purpose designed graphical display is demonstrated in a study investigating the circadian distribution of patterns of RR interval sequences preceding episodes of paroxysmal atrial fibrillation (PAF). Based on a comparison with a (80%, 120%) range around the median of preceding 10 RR intervals, each RR interval is classified as normal, short, or long. Classifications of RR intervals in n-tuplets (n = 1, ...,5) preceding PAF episodes are used to compute probabilities of individual types of sequences occurring within 4-hour periods of the day (between 1 am, 5 am, 9 am, 1 pm, 5 pm, and 9 pm). Graphical representation of the data is proposed using a hierarchy of bar graphs. The graphical system has been filled with data of 327 atrial fibrillation episodes recorded in 46 24-hour ECGs in PAF patients. The graphical analysis supports a link between PAF initiation and cardiac autonomic status.
authors.affiliation: Department of Cardiological Sciences, St. George's Hospital Medical School, London, England.
authors.forename: K
authors.initials: K
authors.lastname: Hnatkova
authors.forename: F D
authors.initials: FD
authors.lastname: Murgatroyd
authors.forename: X
authors.initials: X
authors.lastname: Guo
authors.forename: A J
authors.initials: AJ
authors.lastname: Camm
authors.forename: M
authors.initials: M
authors.lastname: Malik
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001262:Atenolol / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000188:drug therapy / Q000503:physiopathology*; D002940:Circadian Rhythm / Q000502:physiology*; D003196:Computer Graphics; D018592:Cross-Over Studies; D004077:Digoxin / Q000627:therapeutic use; D004206:Disopyramide / Q000627:therapeutic use; D004311:Double-Blind Method; D015716:Electrocardiography, Ambulatory / Q000145:classification / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011336:Probability
chemical_list: D000889:Anti-Arrhythmia Agents; D001262:Atenolol; D004077:Digoxin; D004206:Disopyramide