Acute alterations of pre- and afterload: are Doppler-derived diastolic filling patterns able to differentiate the loading condition?
The net effects of acute changes in pre- and afterload on left ventricular filling, were examined by altering loading conditions in normal subjects. The specific purpose of this study was to investigate whether Doppler-derived transmitral flow patterns are able to differentiate the type of loading conditions. In 24 normal subjects (13 females, 11 males, mean age 44.1 +/- 11.5 years), the following Doppler variables were determined at baseline, after rapid volume infusion (preload increase), after nitroglycerin administration (preload decrease), during isometric exercise (afterload increase), and after application of a converting enzyme inhibitor (afterload decrease): the peak and integrated early (E, Ei) and late (A, Ai) diastolic flow velocities, their ratios (E/A, Ei/Ai), the percentage of atrial contribution (ACON), and the acceleration and deceleration times (Ac, Dc) of early filling. Reduced preload and increased afterload led to similar filling patterns characterized by a significant E and Ei decrease (p < 0.05, compared to baseline) accompanied by an A and Ai increase with a resultant reduction of E/A and Ei/Ai. Both changes increased the atrial contribution to filling and reduced Ac and Dc. Increased preload only significantly increased E and Ei, while reduced afterload did not induce any significant changes. Different loading conditions alter Doppler-derived diastolic filling patterns. However, the transmitral flow profile is not specific enough to distinguish the manner in which loading conditions have been altered.
Völler
H
H
Department of Cardiopulmology, Klinikum Steglitz, University of Berlin, Germany.
Uhrig
A
A
Spielberg
C
C
von Ameln
H
H
Schröder
K
K
Brüggemann
T
T
Schröder
R
R
D000328:Adult; D001794:Blood Pressure / Q000502:physiology; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D012016:Reference Values; D016277:Ventricular Function, Left / Q000502:physiology*; D017725:Ventricular Pressure / Q000502:physiology