Tissue Doppler imaging in hypertrophic cardiomyopathy: impact of intraventricular obstruction on longitudinal left ventricular function.
BACKGROUND
In non-obstructive hypertrophic cardiomyopathy, tissue Doppler imaging of the mitral annulus shows severe systolic and diastolic dysfunction, with marked heterogeneity and asynchrony. In obstructive forms, the complexity of pathophysiological interactions makes conventional echocardiographic functional assessment extremely difficult and complex.


OBJECTIVE
To study longitudinal left ventricular function with tissue Doppler imaging in the obstructive forms of hypertrophic cardiomyopathy.


METHODS
Twenty-six patients with hypertrophic obstructive cardiomyopathy and 23 patients with the non-obstructive form of the disease, matched by age, were studied with pulsed tissue Doppler imaging of the 4 sides of the mitral annulus (septal, lateral, inferior, anterior) in 4 and 2 chamber views. In each wave (systolic-s, rapid filling-e, atrial contraction-a) we analyzed velocities, time intervals and velocity-time integrals, as well as heterogeneity and asynchrony indexes. Data were compared between the different sides in each group, between groups and with conventional Doppler data.


RESULTS
In contrast to the non-obstructive forms, patients with intraventricular obstruction showed: Systolic function: similar velocities and integrals, the relations between the different sides of the annulus usually being preserved; longer isovolumic contraction time, time to peak s and PEP/LVET. Diastolic function: similar rapid filling and e/a velocities and integrals, lower atrial contraction velocity and integral, similar number of sides with e/a higher than or equal to 1 on the lateral and inferior side of the annulus; similar diastolic time intervals, except diastolic time.


CONCLUSIONS
This study shows that the presence of dynamic intraventricular obstruction and the loading conditions of obstructive forms of hypertrophic cardiomyopathy do not significantly influence most annular tissue Doppler imaging parameters, showing the relative load independence of the technique. So, in obstructive hypertrophic cardiomyopathy patients: 1--Longitudinal systolic function (velocities) is similar to the non-obstructive forms--longitudinal systolic dysfunction. 2--Longitudinal diastolic function (velocities and time intervals) is similar to the non-obstructive forms--longitudinal diastolic dysfunction. 3--Left atrial dysfunction is more severe than in non-obstructive forms. 4--The inferior and lateral sides of the annulus should be those selected in order to identify pseudonormalization of the transmitral flow.
Cardim
Nuno
N
Serviço de Cardiologia do Hospital Pulido Valente, Lisboa. corclinica@clix.pt
Torres
Diogo
D
Morais
Humberto
H
Cândido
António
A
Duarte
Rita
R
Longo
Susana
S
Ferreira
Teresa
T
Pereira
Amadeu
A
Gouveia
António
A
Reis
Roberto Palma
RP
Correia
João Martins
JM
D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D016277:Ventricular Function, Left; D014694:Ventricular Outflow Obstruction / Q000150:complications / Q000503:physiopathology*