Sensitivity of the Doppler rate of pressure rise to changes in the inotropic state: an experimental comparison with invasively obtained dP/dt.
OBJECTIVE
To investigate the sensitivity of the rate of pressure rise obtained by Doppler to changes in the inotropic state by comparing it to simultaneous invasive measurements of dP/dt under different conditions of contractility.


RESULTS
Mitral regurgitation was provoked in five pigs, and simultaneous measurements of dP/dt and the Doppler-estimated rate of pressure rise were made with a micro-manometer and with continuous-wave Doppler. Changes in the inotropic state were induced by drug infusion and by ischaemia. One hundred and twenty-seven simultaneous measurements were made with a correlation coefficient between the Doppler-estimated rate of pressure rise and dP/dt of 0.85 (P<0.001). Sensitivity to inotropic changes was estimated as the percentage change of each parameter in each condition of contractility, and showed that the Doppler-estimated rate of pressure rise had better sensitivity than dP/dt.


CONCLUSIONS
The sensitivity of Doppler-estimated rate of pressure rise to changes in the inotropic state is greater than that of dP/dt. The correlation between the rate of pressure rise obtained by Doppler and dP/dt is maintained even in extreme conditions of contractility. Therefore, the rate of pressure rise can be considered a good parameter to assess linear changes of contractility.
García-Lledó
A
A
Department of Cardiology, General Hospital of Guadalajara, Spain.
Moya
J L
JL
Balaguer
J
J
Asín
E
E
D000818:Animals; D001794:Blood Pressure / Q000502:physiology*; D004195:Disease Models, Animal; D018618:Echocardiography, Doppler, Color; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000503:physiopathology; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology; D008955:Models, Cardiovascular; D008962:Models, Theoretical; D015999:Multivariate Analysis; D009200:Myocardial Contraction / Q000502:physiology*; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D013552:Swine