caa a22 4500 475833635 CHVBK 20180406123848.0 cr unu---uuuuu 170329e20000601xx s 000 0 eng 10.1023/A:1007872418215 doi (NATIONALLICENCE)springer-10.1023/A:1007872418215 β-adrenoceptor Modulation and Heart Rate Variability—The Value of Scatterplot Measures of Compactness [Elektronische Daten] [B. Silke, C.G. Hanratty, S.M. Veres, J.G. Riddell] This article compares different methods of scatterplot analysis to assess the optimal methodology. The scatterplot (Poincaré plot) is a nonlinear heart rate variability method where a "return map” is constructed by plotting each current cycle against the previous beat (RR vs. RRn−1). Geometric analysis of the scatterplot allows short-term and long-term heart rate variability (HRV) to be assessed. A three-dimensional construct is also possible, where the third axis represents the density of values, at any given RR vs. RRn−1 intersection. Topological methods of analysis can compute the density distribution function or compactness of a dataset. Scatterplots that otherwise appear very similar in the two-dimensional plot may be clearly differentiated using this approach. Correct characterization may improve the ability of scatterplot analysis to predict outcomes in cardiovascular disease. We have assessed two computational approaches that take account of scatterplot density, namely, the heart rate variability fraction and the compactness measure. Scatterplots were constructed from three double-blind and randomized placebo controlled studies conducted in a total of 49 healthy subjects. Single oral doses of antagonists (atenolol 50 mg [β-1, propranolol 160 mg [β-1 and β-2], and ICI 118,551 25 mg [β-2]) or agonists (xamoterol 200 mg [β-1], salbutamol 8 mg [β-2], prenalterol 50 mg [β-1 and β-2], and pindolol 10 mg [mainly β-2] of the cardiac β-adrenoceptor were studied. Salbutamol, pindolol, and xamoterol increased compactness and reduced HRV fraction significantly compared with placebo. However, when compared with the more conventional scatterplot parameters, these newer density methods were found to be less discriminating. An alternative approach to improve scatterplot discrimination, using the combination of several scatterplot features, is under investigation. Kluwer Academic Publishers, 2000 heart rate variability nationallicence scatterplot nationallicence compactness nationallicence beta-adrenoceptor agonist antagonist nationallicence Silke B. Therapeutics and Pharmacology, The Whitla Division of Medicine, The Queen's University of Belfast, BT97BL, Belfast, Northern Ireland aut Hanratty C.G. Therapeutics and Pharmacology, The Whitla Division of Medicine, The Queen's University of Belfast, BT97BL, Belfast, Northern Ireland aut Veres S.M. The University of Southhampton, SO17 1BJ, Highfield, UK aut Riddell J.G. Therapeutics and Pharmacology, The Whitla Division of Medicine, The Queen's University of Belfast, BT97BL, Belfast, Northern Ireland aut Cardiovascular Drugs and Therapy Kluwer Academic Publishers 14/4(2000-06-01), 433-440 0920-3206 14:4<433 2000 14 10557 https://doi.org/10.1023/A:1007872418215 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1007872418215 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Silke B. Therapeutics and Pharmacology, The Whitla Division of Medicine, The Queen's University of Belfast, BT97BL, Belfast, Northern Ireland aut NATIONALLICENCE 700 1- Hanratty C.G. Therapeutics and Pharmacology, The Whitla Division of Medicine, The Queen's University of Belfast, BT97BL, Belfast, Northern Ireland aut NATIONALLICENCE 700 1- Veres S.M. The University of Southhampton, SO17 1BJ, Highfield, UK aut NATIONALLICENCE 700 1- Riddell J.G. Therapeutics and Pharmacology, The Whitla Division of Medicine, The Queen's University of Belfast, BT97BL, Belfast, Northern Ireland aut NATIONALLICENCE 773 0- Cardiovascular Drugs and Therapy Kluwer Academic Publishers 14/4(2000-06-01), 433-440 0920-3206 14:4<433 2000 14 10557 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer