title: Right ventricular dP/dt/P(max), not dP/dt(max), noninvasively derived from tricuspid regurgitation velocity is a useful index of right ventricular contractility.
abstract: BACKGROUND
  Although right ventricular (RV) contractility is important in determining functional capacity, few quantification methods are clinically available. RV dP/dt(max) can be assessed by Doppler echocardiography by using tricuspid regurgitation (TR) but is not routinely used because of its dependency on a Doppler incident angle and preload. Doppler-derived dP/dt/P(max) is relatively insensitive to preload and theoretically independent of the incident angle. We investigated the clinical feasibility of this index as an RV contractility index.
  
  
  METHODS
  We computed RV dP/dt(max) and dP/dt/P(max) from the TR-derived RV pressure in 68 patients with dominant RV failure (13 in New York Heart Association [NYHA] class I, 33 in class II, 17 in class III, and 5 in class IV). Peak oxygen consumption (peak VO(2)) was measured in 20 patients during a maximal bicycle ergometer test.
  
  
  RESULTS
  dP/dt(max) did not significantly correlate with NYHA class. In contrast, dP/dt/P(max) decreased monotonically with the functional class (r = -0.49, P <.0001), and correlated with peak VO(2) (r = 0.66, P <.002).
  
  
  CONCLUSIONS
  TR-derived dP/dt/P(max), not dP/dt(max), is a clinically useful index of RV contractility, allowing researchers to account for the functional capacity.
authors.affiliation: Department of Cardiology, Research Institute, National Cardiovascular Center, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kanzaki
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakatani
authors.forename: Toru
authors.initials: T
authors.lastname: Kawada
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yamagishi
authors.forename: Kenji
authors.initials: K
authors.lastname: Sunagawa
authors.forename: Kunio
authors.initials: K
authors.lastname: Miyatake
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity; D015150:Echocardiography, Doppler; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D010100:Oxygen / Q000378:metabolism; D011312:Pressure; D014262:Tricuspid Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016278:Ventricular Function, Right / Q000502:physiology*
chemical_list: D010100:Oxygen