title: A novel noninvasive method to assess left ventricular -dP/dt using diastolic blood pressure and isovolumic relaxation time.
abstract: BACKGROUND
  Left ventricular Doppler-derived -dP/dt determined from the continuous-wave Doppler spectrum of the mitral regurgitation (MR) jet has been shown to be a valuable marker of diastolic function, but requires the presence of MR for its assessment. We sought to determine if a novel method of determining -dP/dt using the diastolic blood pressure and isovolumic relaxation time (DBP-IVRT method) correlates with Doppler-derived -dP/dt using the MR method (Doppler-MR method).
  
  
  METHODS
  Thirty-three patients with less than severe MR were enrolled. -dP/dt was determined using the Doppler-MR method from the continuous-wave Doppler spectrum of the MR jet (32 mmHg/time from 3 to 1 m/sec). -dP/dt was also determined using the DBP-IVRT method using the following equation: -dP/dt = (DBP - LVEDP)/IVRT, where left ventricular end-diastolic pressure (LVEDP) was estimated based on tissue Doppler and mitral inflow patterns.
  
  
  RESULTS
  Twenty-five patients had adequate Doppler waveforms for analysis. The average amount of MR was mild-to-moderate severity. The mean -dP/dt was 680 ± 201 mmHg by the Doppler-MR method and 681 ± 237 mmHg by the DBP-IVRT method. There was a significant correlation between the 2 methods of determining -dP/dt (Pearson r = 0.574, P = 0.003). The Bland-Altman plot revealed almost no bias between the 2 methods; the difference in -dP/dt between the 2 techniques was noted to be greater for patients with higher -dP/dt, however.
  
  
  CONCLUSIONS
  Diastolic blood pressure and isovolumic relaxation time may be used to noninvasively assess diastolic function in patients who do not have MR, especially in those with reduced diastolic function.
authors.affiliation: University of Michigan Hospital and Health Systems, Ann Arbor, MI 48109-5853, USA.
authors.forename: Rupal
authors.initials: R
authors.lastname: Parekh
authors.forename: Theodore J
authors.initials: TJ
authors.lastname: Kolias
mesh_terms: D000368:Aged; D001795:Blood Pressure Determination / Q000379:methods*; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D009200:Myocardial Contraction; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000503:physiopathology*