Contrasting hemodynamic mechanisms of losartan- vs. atenolol-based antihypertensive treatment: a LIFE study.
BACKGROUND
Pharmaceutical differences in central hemodynamics might influence cardiac response to antihypertensive treatment despite similar lowering of brachial blood pressure (BP).


METHODS
Data from all patients with at least two echocardiographic examinations in the Losartan Intervention For Endpoint Reduction in Hypertension (LIFE) echocardiographic substudy (n = 801); high-risk patients on losartan- vs. atenolol-based antihypertensive therapy. Echocardiography was performed annually for 4 years to measure stroke index (SI), heart rate, cardiac index (CI), conduit artery stiffness assessed as pulse pressure/stroke index (PP/SI) and total peripheral resistance index (TPRI).


RESULTS
Atenolol- and losartan-based therapy reduced BP similarly (cumulative difference in mean brachial blood pressure 0.3 mm Hg, P = 0.65). After 4 years the cumulative means of SI and heart rate were 1.8 ml/m(2) higher and 5.7 beats/min lower on atenolol-based treatment, respectively (both P < 0.001). This kept CI below baseline in atenolol-treated patients, whereas in the losartan group CI was unchanged from baseline throughout the study. TPRI was decreased more and remained lower in the losartan group (cumulative difference in mean TPRI 287 dynes/sec(-5)/cm/m(2), P < 0.001). These findings partly explained univariate differences in systolic- and diastolic function indices between the two treatments; fully adjusted losartan was only associated with a smaller left atrial diameter (cumulative mean difference 0.07 cm; 95% confidence intervals, -0.13 to -0.01, P = 0.03).


CONCLUSIONS
Contrasting hemodynamics impacted cardiac response to similar reductions in brachial BP on losartan- vs. atenolol-based therapy. The similar reduction of PP/SI suggests that the antihypertensive regimens used in the LIFE study had comparable effects on arterial stiffness (LIFE study; NCT00338260)
Department of Medicine B, The Heart Center, Rigshospitalet, Copenhagen, Denmark. greve_anders@hotmail.com
Anders M
AM
Greve
Michael H
MH
Olsen
Jonathan N
JN
Bella
Mai T
MT
Lønnebakken
Eva
E
Gerdts
Peter M
PM
Okin
Vittorio
V
Palmieri
Kurt
K
Boman
Markku S
MS
Nieminen
Per
P
Omvik
Björn
B
Dahlöf
Richard B
RB
Devereux
Kristian
K
Wachtell
D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001262:Atenolol / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology*; D017379:Hypertrophy, Left Ventricular / Q000503:physiopathology; D019808:Losartan / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged
D000959:Antihypertensive Agents; D001262:Atenolol; D019808:Losartan