title: Correlation between Doppler derived dP/dt and left ventricular asynchrony in patients with dilated cardiomyopathy: A combined study using strain rate imaging and conventional Doppler echocardiography.
abstract: OBJECTIVE
  To evaluate the relationship between Doppler-derived left ventricular (LV) dP/dt and the degree of LV mechanical asynchrony measured by strain rate imaging.
  
  
  RESULTS
  The study group consisted of 69 patients with variable degree of LV dysfunction and mitral regurgitation (MR). Conventional echo variables and LV dP/dt were calculated from the MR Doppler spectrum by rate-pressure-rise method. Strain rate traces were obtained by 12-segment model and LV long axis images were analyzed off-line. The longest time intervals between the peak negative strain rate waves at isovolumic contraction period and peak systole from reciprocal segments were defined as asynchrony index AIc or AIs, respectively. The maximum differences in time-to-peak systolic velocities between opposing walls were also measured as asynchrony index by tissue Doppler (AItd). The dP/dt, mean QRS duration, AIc, AIs, and AItd were 836 +/- 266 mmHg/sec, 125 +/- 31, 38 +/- 28, 64 +/- 44, and 52 +/- 32 m, respectively. No significant correlation between the dP/dt and the LV dimension, ejection fraction or QRS duration was observed. However, dP/dt correlated negatively with AIc, or AIs (r:-0.78, -0.72, P < or = 0.0001) and AItd (r:-0.65, P < or = 0.001). A cutoff dP/dt value of under 700 mmHg/sec can discriminate patients over median AIs (55 ms) or patients with AIc over 30 ms with high sensitivity and specificity.
  
  
  CONCLUSIONS
  Doppler-derived LV dP/dt is related to the degree of LV dyssynchrony rather than the conventional systolic function indices such as EF% in patients with severe heart failure. Noninvasive dP/dt assessment in addition to advanced imaging techniques can be used to define patients for cardiac resynchronization therapy (CRT).
authors: Siyami Ersek Cardiovascular Surgery Center, Istanbul, Turkey. draydinyildirim@yahoo.com
authors: Aydin
authors: A
authors: Yildirim
authors: Ozer
authors: O
authors: Soylu
authors: Bahadir
authors: B
authors: Dagdeviren
authors: Utku
authors: U
authors: Zor
authors: Tuna
authors: T
authors: Tezel
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology*; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D006339:Heart Rate; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D015588:Observer Variation; D015203:Reproducibility of Results; D012107:Research Design; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology*