2.1 Study population
We prospectively evaluated 60 consecutive CKD patients 40-75 years old
who were followed-up at the CKD outpatient clinic of the University
Hospital of Ioannina, Greece, between January 2013 and December 2014.
The study protocol was previously approved by the local ethics
committee. Exclusion criteria were: 1) history of coronary artery
disease (CAD) and other established atherosclerotic disease i.e.
cerebrovascular and peripheral arterial disease, 2) LV ejection fraction
<50%, 3) any moderate-severevalvular heart disease (VHD), 4)
atrial fibrillation, 5) advanced atrioventricular conduction disorder,
6) poor acoustic window during echocardiographic examination, 7) history
of congestive heart failure, cardiomyopathy or constrictive pericarditis
and 8) known allergy to dipyridamole or history of asthma/severe chronic
obstructive pulmonary disease (COPD).
From a total of 106 patients attending the CKD outpatient clinic of our
hospital, 46 patients were excluded at the time of study enrollment, due
to poor acoustic window (16 patients), moderate-severe VHD (8 patients),
presence of not previously known atrial fibrillation (6 patients),
history of asthma/severe COPD (4 patients), asymptomatic (not previously
known) CAD (8 patients), allergic reaction during dipyridamole infusion
(1 patient) and denial to participate to the protocol (3 patients). The
remaining patients (n=60) were divided and analyzed in two subgroups
according to a cut-off at the age of 60 years. In the current study 30
healthy controls (40-60 years old) that were age- and gender-matched to
younger CKD patients (i.e. <60 years old), were also enrolled.
Finding healthy subjects in the specific age span without any known risk
factor and without taking any medication was more difficult than
originally thought. All patients (CKD and healthy controls) underwent a
thorough physical examination and a detailed echocardiographic
assessment. The study complied with the Declaration of Helsinki. All
participants provided a written informed consent.