Cerebral blood flow as a marker for recovery of left ventricular systolic dysfunction in patients with idiopathic dilated cardiomyopathy

Effects of Physical Exercise on Cerebral Blood Velocity in Older Adults: A Systematic Review and Meta-Analysis

As the older population grows, there is an increasing interest in understanding how physical exercise can counteract the changes seen with aging. The benefits of exercise to general health, and especially to the cardiovascular system, have been a topic of discussion for decades. However, there is still a need to elucidate the effects of training programs on the cerebrovascular blood velocity in older people. This systematic review and meta-analysis aimed to investigate the effect of physical exercise on the cerebral blood velocity in older people (PROSPERO CRD42019136305). A search was performed on PubMed, Web of Science, EBSCO, ScienceDirect, and Scopus from the inception of this study to October 2023, retrieving 493 results, of which 26 were included, analyzing more than 1000 participants. An overall moderate risk of bias was found for the studies using the Cochrane risk-of-bias tools for randomized and non-randomized clinical trials. The pooled results of randomized trials showed that older people who underwent physical exercise presented a statistically significant increase in cerebral blood velocity (3.58; 95%CI = 0.51, 6.65; p = 0.02). This result indicates that physical exercise is important to help maintain cerebral health in older adults.

Cerebral blood flow impairment and cognitive decline in heart failure

BACKGROUND AND PURPOSE

Cognitive decline is an important contributor to disability in patients with chronic heart failure, affecting 25%-50% of patients. The aim of this review is to stress the importance of understanding pathophysiological mechanisms of heart failure involved in cognitive decline.

METHODS

An extensive PubMed search was conducted for the literature on the basic mechanisms of cerebral blood flow regulation, the effect of cardiac dysfunction on cerebral blood flow, and possible mechanisms underlying the association between cardiac dysfunction and cognitive decline.

RESULTS

Published literature supports the thesis that cardiac dysfunction leads to cerebral blood flow impairment and predisposes to cognitive decline. One of the postulated mechanisms underlying cognitive decline in chronic heart failure is chronic regional hypoperfusion of critical brain areas. Cognitive function may be further compromised by microvascular damage due to cardiovascular risk factors. Furthermore, it is implied that cerebral blood flow assessment could enable early recognition of patients at risk and help guide appropriate therapeutic strategies.

CONCLUSION

Interdisciplinary knowledge in the fields of neurology and cardiology is essential to clarify heart and brain interconnections in chronic heart failure. Understanding and identifying the basic neuropathophysiological changes in chronic heart failure could help with developing methods for early recognition of patients at risk, followed by institution of therapeutic actions to prevent or decrease cognitive decline.

Increased prevalence of cerebral microbleeds in patients with low left ventricular systolic function

Gradient-echo T2-star (T2*)-weighted magnetic resonance imaging (MRI) is a sensitive method to detect cerebral microbleeds (CMBs). The presence of CMBs was reported to be a marker of future cardiovascular mortality and is associated with various cardiovascular risk factors, use of antithrombotic drugs, and cognitive dysfunction. However, the relationship between cardiac function and CMBs remains unclear. We investigated the association between cardiac function and presence of CMBs in patients with cardiovascular diseases. This single-center retrospective study included a total of 424 participants (mean age 70 ± 12 years; men 286 (67%); mean left ventricular ejection fraction (LVEF) 61% ± 12%] who underwent echocardiography and brain T2*-weighted MRI within 1 month without neurologic abnormality. CMBs were found in 118 (28%) patients. There was no significant relationship between CMBs and anticoagulant or antiplatelet therapy. LVEF was significantly lower in patients with CMBs than in those without CMBs (59% ± 13% vs. 62% ± 11%, P < 0.05). On multivariate logistic analysis, lower LVEF [odds ratio (OR) 0.98, 95% confidence interval (CI) 0.96-1.00; P < 0.05] and age (OR 1.02, 95% CI 1.00-1.05; P < 0.05) were significantly associated with CMBs. The presence of CMBs was frequently observed in the patients with cardiovascular disease and was significantly associated with age and LVEF.

Heart and brain interconnection - clinical implications of changes in brain function during heart failure

Heart failure (HF) is a highly prevalent disorder worldwide and, consequently, a burden on the healthcare systems of many nations. Although the effects of HF are systemic, many therapeutic targets are focused on cardiac dysfunction. The brain is closely related to the heart, but there are few reports on the relationship between these organs. We describe the effects of the brain on HF progression. Specific brain regions control sympathetic drive and neurohumoral factors, which play an important role in disease exacerbation. In addition, we review some of our previous studies on deranged cerebral metabolism and reduced cerebral blood flow during HF. Although the reasons underlying these effects during HF remain uncertain, we propose plausible mechanisms for these phenomena. In addition, the clinical implications of such conditions in terms of predicting prognosis are discussed. Finally, we investigate cognitive impairment in patients with HF. Cognitive impairment through cerebral infarction or hypoperfusion is associated with adverse outcomes, including death. This brief review of brain function during the development of HF should assist with future strategies to better manage patients with this condition.

Frequency and predictors of normalization of left ventricular ejection fraction in recent-onset nonischemic cardiomyopathy

Emerging evidence has shown the potential of marked improvement in left ventricular ejection fraction (LVEF) in patients with recent-onset cardiomyopathy (ROCM) on medical therapy. This study was designed to determine the frequency and to identify predictors of normalization of LVEF in a cohort of Chinese patients with ROCM receiving contemporary medication. A consecutive series of patients admitted from October 2008 to November 2012 with the clinical diagnosis of ROCM and LVEF ≤ 40% by echocardiography at presentation were followed up at least 12 months to identify those with normalization of LVEF, defined as an increase in LVEF to a final level of ≥ 50%. An array of clinical and echocardiographic variables regarded as potentially relevant to normalization was evaluated to identify predictors using logistic regression analysis. After a mean follow-up of 31 ± 13 months, 48% of 128 patients had normalized their LVEF, showing a significant increase in LVEF from 32 ± 6% to 58 ± 5%, of which 68% occurred within 1 year after initial diagnosis. Multivariate analysis demonstrated that normalization of LVEF was associated with a history of hypertension, higher systolic blood pressure at presentation, shorter electrocardiographic QRS duration, smaller left ventricular end-diastolic diameter, and higher LVEF by echocardiography at baseline. In conclusion, nearly 1/2 of a relatively large number of Chinese patients with ROCM have shown normalization of LVEF on current medical therapy after a medium-term follow-up, which was associated with some clinical and echocardiographic parameters.