Influence of cardiopulmonary bypass on the plasma concentrations of atenolol.
BACKGROUND
Betablockers are used in the treatment of angina pectoris and others ischemic coronary diseases, reducing mortality and cardiovascular events. Atenolol is a hydrophilic betablocker which is characterized by gastrointestinal absorption, small extent of distribution and renal function-dependent elimination.


OBJECTIVE
The study objective was to determine the inter-individual variability of atenolol in coronary patients.


METHODS
Plasma atenolol was quantified in six blood samples collected during the preoperative period from seven patients with coronary insufficiency and surgical indication, chronically treated with atenolol PO 25 to 100 mg/day. All patients presented a normal or slightly reduced renal function.


RESULTS
All enrolled patients presented normal or slightly reduced renal function as a result of age and underlying disease. Atenolol plasma concentrations showed a monoexponential decline, confirming the first-order pharmacokinetics at the doses employed for the control of coronary insufficiency (mean +/- SD): 123 +/- 56, 329 +/- 96, 288 +/- 898, 258 +/- 85, 228 +/- 79 and 182 +/- 73 ng/ml at times zero, 2, 4, 6, 8 and 12h after dose administration. The investigated group showed a small inter-patient variability of atenolol administrated at multiple regimens due to the hydrophilic characteristic of the drug. Furthermore, accumulation of atenolol administered chronically was greater in coronary patients, compared to healthy subjects.


CONCLUSIONS
In view of its cardio-selectivity and low-variability, atenolol should be used as the first-choice drug for the treatment of acute coronary syndrome and other cardiovascular diseases.
Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Instituto do Coração do Hospital das Clínicas, FMUSP, São Paulo, SP, Brazil.
Fátima da Silva
Fda S
Leite
Luciana Moraes
LM
dos Santos
Wanderley Wesley
WW
Bonafé
Andréia Zago
AZ
Chignalia
Maria José Carvalho
MJ
Carmona
Mariana Junqueira
MJ
Suyama
Luiz Marcelo Sá
LM
Malbouisson
José Otavio Costa
JO
Auler
Silvia Regina Cavani Jorge
SR
Santos
D000284:Administration, Oral; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D000368:Aged; D001262:Atenolol / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D002315:Cardiopulmonary Bypass / Q000379:methods*; D002908:Chronic Disease; D005260:Female; D006801:Humans; D007668:Kidney / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009204:Myocardial Revascularization; D011300:Preoperative Care; D018709:Statistics, Nonparametric; D013997:Time Factors
D000319:Adrenergic beta-Antagonists; D001262:Atenolol