Recent data have associated blood pressure variability (BPV) with subclinical renal damage, acute renal injury and progression of chronic kidney disease but not in the setting of an acute coronary event. The aim of this study is to determine the impact of in-hospital short-term BPV on future renal impairment in patients suffering an acute myocardial infarction (AMI).
A total population of 63 AMI patients [87.3% male; mean age: 65.1 years; 76.2% hypertensives; 19% chronic kidney disease (GFR<60 ml/min on admission); 52.4% STEMI] who underwent 24-h ambulatory BP measurement during their hospitalization were followed-up at one year for assessment of their present renal function. Renal impairment was defined as a reduction of GFR > or = 25% between discharge and one-year visit according to the RIFLE criteria, calculated using the Cockcroft-Gault Equation. The parameters of BPV analyzed were: a) the 24-h standard deviation (SD), b) the coefficient of variation (CV) and c) the average real variability (ARV) of systolic and diastolic BP.
After analysis of BPV indices, one-year renal impairment was significantly associated with increased in-hospital SBP CV (hazard ratio, 1.489; CI, 0.200–2.778; p = 0.024). Therefore, a multivariate regression analysis was conducted, in which SBP CV maintained a significant prognostic role of renal impairment [odds ratio, 1.414; CI, 0.013–2.816 (P = 0.048)], independently of age, gender, body mass index (BMI), history of hypertension, DM, ejection fraction (EF) and the type of MI.
In the setting of AMI, assessment of in-hospital BPV using SBP CV has a prognostic role in the future development of renal dysfunction. This observation, if confirmed by further studies, could influence the therapeutic approach of ACS in terms of BP management.
First Cardiology Clinic, Medical School, National and Kapodistrian University of Athens, Hippokration Hospital, Athens, GREECE