Independent and interactive effects of blood pressure and cardiac function on brain volume and white matter hyperintensities in heart failure

Background: Reduced systemic perfusion and comorbid medical conditions are key contributors to adverse brain changes in heart failure (HF). Hypertension, the most common co-occurring condition in HF, accelerates brain atrophy in aging populations. However, the independent and interactive effects of blood pressure and systemic perfusion on brain structure in HF have yet to be investigated. Methods: Forty-eight older adults with HF underwent impedance cardiography to assess current systolic blood pressure status and cardiac index to quantify systemic perfusion. All participants underwent brain magnetic resonance imaging to quantify total brain, total and subcortical gray matter volume, and white matter hyperintensities (WMH) volume. Results: Regression analyses adjusting for medical and demographic factors showed decreased cardiac index was associated with smaller subcortical gray matter volume (P <.01), and higher systolic blood pressure predicted reduced total gray matter volume (P =.03). The combination of higher blood pressure and lower cardiac index exacerbated WMH (P =.048). Conclusions: Higher blood pressure and systemic hypoperfusion are associated with smaller brain volume, and these factors interact to exacerbate WMH in HF. Prospective studies are needed to clarify the effects of blood pressure on the brain in HF, including the role of long-term blood pressure fluctuations.