Left atrial energy in normal subjects, in patients with symptomatic mitral stenosis, and in patients with advanced heart failure.
In a population consisting of 45 subjects (15 patients with mitral stenosis, 15 patients with heart failure, and 15 normal subjects), the left atrial (LA) pressure-area relation was assessed and the correlations between LA stroke work, LA kinetic energy, and LA ejection force were studied. The area of the counterclockwise A loop expressing the LA external work was measured. LA kinetic energy was obtained from the formula: 1/2 x stroke volume x 1.06 x v2, where v = transmitral Doppler A velocity. An excellent correlation was found between LA stroke work index and LA kinetic energy when data from all patients were plotted together (r = 0.95, p <0.001). The Pearson's correlation similarity coefficient between LA ejection force and kinetic energy as well as between LA ejection force and stroke work index was r = 0.54 (p <0.001). The r value of 0.54 was significantly lower than r = 0.95 (p <0.03). LA kinetic energy extends the use of transmitral flow Doppler data to include assessment of LA work. LA work can be obtained noninvasively with a high degree of accuracy.
Stefanadis
C
C
Department Cardiology, Hippokration Hospital, University of Athens, Greece.
Dernellis
J
J
Lambrou
S
S
Toutouzas
P
P
D016275:Atrial Function; D016279:Atrial Function, Left / Q000502:physiology*; D015150:Echocardiography, Doppler; D006325:Heart Atria / Q000000981:diagnostic imaging; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D007700:Kinetics; D008946:Mitral Valve Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology*; D012016:Reference Values; D015203:Reproducibility of Results; D013318:Stroke Volume