Tissue velocity echocardiography shows early improvement in diastolic function with irbesartan and atenolol therapy in patients with hypertensive left ventricular hypertrophy. Results form the Swedish Irbesartan Left Ventricular Hypertrophy Investigation vs Atenolol (SILVHIA).
BACKGROUND
Abnormal diastolic function is common in hypertensive left ventricular hypertrophy (LVH). Early identification and treatment may prevent future cardiovascular events.


METHODS
We examined 58 hypertensive patients with LVH, 38 with hypertension but no LVH, and 38 normotensive subjects. The effects of the AT1 receptor blocker irbesartan and the beta1 blocker atenolol on diastolic function during 48 weeks of treatment were evaluated in the LVH group by tissue velocity echocardiography (TVE). We measured basal septal and lateral wall velocities of early (Em) and late (Am) diastolic myocardial wall motion, Em velocity deceleration time (E-decm), and isovolumic relaxation time (IVRTm). For comparison, diastolic function was assessed by conventional mitral pulse wave Doppler echocardiography.


RESULTS
Diastolic function was impaired in both hypertensive groups. Irbesartan and atenolol (week 48, septal wall) improved IVRTm (-44%, P<.001, and -19%, P<.001; P<or=.001 between groups), E-decm (+56%, P<.001, and +53%, P<.001), and Em/Am (+11%, P=.396, and +20%, P=.010). Only irbesartan improved E/Em (-4%, P=.052 v +2%, P=.041). For irbesartan, relative changes in IVRTm and in septum thickness were related (P=.017), whereas relative changes in the Em/Am ratio and in heart rate were related for atenolol (P=.027). Alterations in diastolic dysfunction were greater and detected earlier with TVE than with conventional echocardiography.


CONCLUSIONS
The TVE is more sensitive than conventional echocardiography in detecting alterations in diastolic function. Both irbesartan and atenolol improve diastolic function, but through different mechanisms. The improvement in IVRTm was greater with irbesartan, and only irbesartan improved E/Em. This may have implications on the treatment of high risk hypertensive patients.
Müller-Brunotte
Richard
R
Division of Internal Medicine, Karolinska Institutet Danderyd Hospital, Stockholm, Sweden. richard.muller-brunotte@ds.se
Kahan
Thomas
T
Malmqvist
Karin
K
Ring
Margareta
M
Edner
Magnus
M
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D047228:Angiotensin II Type 1 Receptor Blockers / Q000627:therapeutic use*; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001262:Atenolol / Q000627:therapeutic use*; D001713:Biphenyl Compounds / Q000627:therapeutic use*; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D015986:Confounding Factors, Epidemiologic; D003971:Diastole / Q000187:drug effects; D004311:Double-Blind Method; D015150:Echocardiography, Doppler; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D000077405:Irbesartan; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume / Q000187:drug effects; D013548:Sweden / Q000453:epidemiology; D013777:Tetrazoles / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000187:drug effects
D000319:Adrenergic beta-Antagonists; D047228:Angiotensin II Type 1 Receptor Blockers; D000959:Antihypertensive Agents; D001713:Biphenyl Compounds; D013777:Tetrazoles; D001262:Atenolol; D000077405:Irbesartan