Coronary microcirculation is disturbed in patients with arterial hypertension. Carotid intima-media thickness (IMT) and arterial stiffness are markers of subclinical atherosclerosis with prognostic significance. We investigated whether the combination of increased carotid IMT and arterial stiffness has a greater predictive value for the presence of impaired coronary flow reserve (CFR) than each index alone in never-treated hypertensives. We studied 110 untreated patients (age: 54.5+/-12 years) with newly diagnosed arterial hypertension. We measured (1) carotid-to-femoral artery pulse wave velocity (PWV), (2) carotid IMT and (3) CFR by means of color-guided Doppler echocardiography after adenosine infusion. Among other confounders, arterial stiffness and IMT were independent determinants of CFR (coefficient B=-0.146 and B=-0.006, P<0.05). Arterial stiffness and IMT had an incremental value for the determination of CFR when added to a model including other confounders (chi(2) change=4.423, P for change=0.038 after addition of IMT; and chi(2) change=5.369, P for change=0.020 after addition of PWV). Receiver operating curve analysis showed that PWV>10.2 m s(-1) and IMT>1 mm were the optimal cutoff values to predict a CFR<2.5. Patients with IMT>1 mm, PWV>10.2 m s(-1) or their combination had an odds ratio of 3.5, 5.0 and 11.2, P<0.05, for a CFR<2.5, respectively. The combination of increased carotid IMT and arterial stiffness has a greater predictive value for impaired CFR than each index alone in never-treated hypertensives.