This discrepancy may be explained that in the patients with more severe CHF such as those in the study of Choi et al., factors other than LVEF contributed more to CBF, such as NYHA functional class and neurohormonal activation. Our recent published data presents this website relation between CBF reduction and neurohormonal activation in CHF patients [22]. The same study reported an inverse association between CBF with RVSP which is in agreement with our finding. Finally, reduced CBF in our study was significantly associated with impaired physical performance; measured by 6-min walk test contrary to previous data [19]. The 6-min walk test is a safe and simple clinical tool that strongly and independently predicts morbidity

and mortality in patients with CHF [23]. Color duplex volumetric test of the brain-feeding arteries can only yield information about the RG7422 clinical trial relative contributions of the anterior and posterior cerebral circulation to global CBF volume. We found a contribution of the VA to global CBF volume of 25% which remained almost constant with increasing age. Previously, it was estimated that the VA contribute 24% of the global CBF volume in healthy subjects [24]. To date, there are no reports on the relative contributions of

the anterior and posterior circulation to global CBF volume in patients with CHF. Carotid intima-media thickness was greater in our patients with CHF compared to healthy controls. High carotid intima-media thickness was marked as an independent risk factor for incidence of heart failure requiring hospitalisation [25]. Increased carotid intima-media thickness was shown to be a powerful predictor of coronary and cerebrovascular events, as well [26]. Although both parameters were impaired in our patients, the lack of a link between them suggests that they may represent independent surrogates that measure different pathophysiological aspect

of heart failure progression. The limitation of our study is a relatively small number of studied patients. Our cohort comprised a highly selected CHF sample and is thus less representative of the overall CHF population. The relations between CBF and different variables were examined in a cross-sectional study, which cannot prove a causal relation between these variables. color duplex volumetric examination of the brain feeding extracranial not arteries is a highly reproducible and noninvasive technique. The reliability of the method should be confirmed in comparative studies with established radionuclide procedures which is difficult for ethical reasons. However, reduction of CBF in our patients with CHF compared to healthy controls was similar to the value obtained by radionuclide technique. In this study, we did not perform evaluation of mental status or brain imaging. Therefore, we cannot say that reduced CBF was associated with neuropsychiatric or brain morphologic disorders among patients with CHF.