Left ventricular filling in hypertensive blacks and whites following adrenergic blockade.
Left ventricular diastolic filling was investigated in 12 black and 15 white subjects before and after double-blinded randomized treatment of mild to moderate hypertension with combined alpha- and beta-adrenergic receptor blockade (labetalol) and beta-blockade alone (atenolol). At baseline (off medication), both groups were similar for age (46 +/- 8 years v 48 +/- 12 years), mean blood pressure (121 +/- 8 mm Hg v 115 +/- 8 mm Hg), left ventricular dimensions, left ventricular mass index (118 +/- 24 g/m2 v 113 +/- 13 g/m2), and left ventricular filling as reflected by transmitral flow velocity ratio A/E (0.97 +/- 0.33 v 0.92 +/- 0.19, normal age-matched control A/E ratio is 0.64 +/- 14). There were 6 blacks and 6 whites in the labetalol group; 6 blacks and 9 whites in the atenolol group. At six weeks of treatment, whites in the labetalol group showed a significantly greater drop in mean blood pressure (114 +/- 7/102 +/- 11, P less than .007 v 123 +/- 9/114 +/- 11, P = NS) and correspondingly greater improvement in A/E ratio (1.04 +/- 0.14/0.74 +/- 0.23, P less than .024 v 1.02 +/- 0.23/0.89 +/- 0.16, P = NS). However, this difference was no longer significant when controlling for age and blood pressure level. In the atenolol group, whites showed a significant increase in the rapid filling phase velocity E, while late filling phase velocity A significantly dropped only in blacks, without significant improvement in A/E ratio in either subgroup. In conclusion, greater improvement in left ventricular filling is seen with combined alpha-beta-blockade than beta-blockade alone.(ABSTRACT TRUNCATED AT 250 WORDS)
Department of Medicine, Allegheny General Hospital, Pittsburgh, PA 15212.
S B
SB
Dianzumba
D
D
DiPette
C R
CR
Joyner
C
C
Cornman
R
R
Townsend
K
K
Mauro
E
E
Weber
T
T
Theobald
D000328:Adult; D000704:Analysis of Variance; D001262:Atenolol / Q000494:pharmacology*; D044383:Black People; D002306:Cardiac Volume / Q000187:drug effects*; D003971:Diastole; D004311:Double-Blind Method; D015150:Echocardiography, Doppler; D005260:Female; D006352:Heart Ventricles / Q000187:drug effects / Q000503:physiopathology*; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000503:physiopathology*; D007741:Labetalol / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic; D014481:United States; D044465:White People; D001741:Black or African American
D001262:Atenolol; D007741:Labetalol