Abstract
Purpose
Heart and brain interaction is a well-known entity in heart failure (HF) and left ventricular systolic dysfunction poses an increased risk for stroke and cognitive impairment. Transcranial Doppler (TCD) provides valuable information on cerebral blood flow and detects microembolic signals that can be used to determine the risk of cerebrovascular events. However, less is known about cerebral blood flow in HF patients with reduced EF. So, we aimed to evaluate cerebral blood flow rates by means of TCD in HF patients with reduced ejection fraction (EF).
Methods
This study included 46 HF patients with an EF less than 35% (mean age 65.2±11 years, mean EF 20.1±3.8%) who underwent to TCD examination. In addition, 26 healthy individuals with sinus rhythm and EF >50% (mean age 64.4±9.0 years, mean EF 63.5±2.38%) were included in the study as a control group. Minimum, maximum and mean flow velocities of the both right middle cerebral artery (RMCA) and left middle cerebral artery (LMCA) determined by TCD were analyzed.
Results
The average of RMCA maximum and mean flow velocities were found to be significantly lower in HF patients than those in control group (76,06±23,7 cm/s and 48,49±16,4 cm/s in HF group vs 87,84±14,5 cm/s and 56,41±10,7 cm/s in control group, p=0,025 and p=0,016, respectively). The average of LMCA maximum and mean flow velocities were also significantly lower in HF patients than those in control group (75,1±22,3 cm/s and 47,57±14.8 cm/s in HF group vs 88,73±17,7 cm/s and 57,15±12,4 cm/s in control group, p=0,009 and p=0,007, respectively). However, there was no significant difference in minimum RMCA or LMCA flow velocities between HF group and control groups (33,5±10,6 cm/s and 32,86±9,58 cm/s in HF group vs 36,34±9,2 cm/s and 36,53±10,4 cm/s in control group, p=0,226 and p=0,157, respectively). No significant microembolic signals were detected in HF and control groups.
Conclusions
The results of this study showed that HF patients with reduced EF have lower cerebral blood flow velocities as compared to healthy controls, which might be one of the explanations of the adverse interaction between heart and brain in HF.
Patients With Heart Failure With Reduced Ejection Fraction Have Exaggerated Reductions in Cerebral Blood Flow During Upright Posture ∗
