Survivor’s Remorse

How do cardiovascular risk factors correlate with post-stroke cognitive function: Directly or indirectly through stroke severity?

Objectives

Cognitive impairment may affect one-third of stroke survivors. Cardiovascular risk factors and stroke severity were known to be associated with cognitive function after stroke. However, it is unclear whether cardiovascular risk factors directly affect cognition after stroke, indirectly affect cognition by changing stroke severity, or both. Moreover, the effect of a combination of hypertension and diabetes mellitus was conflicting. We aimed to investigate the multiple direct and indirect associations and inspire potential intervention strategies.

Materials and methods

From February 2020 to January 2021, 350 individuals received cognitive tests within 7 days after incident stroke. Cognitive tests were performed using the Chinese version of the Mini-Mental State Examination (MMSE). A moderated mediation model was constructed to test the indirect associations between cardiovascular and demographic risk factors and cognition mediated through stroke severity, the direct associations between risk factors and cognition, and the moderating effects of hypertension and diabetes.

Results

Age (estimate, -0.112), atrial fibrillation (estimate, -4.092), and stroke severity (estimate, -1.994) were directly associated with lower cognitive function after stroke. Vascular disease (estimate, 1.951) and male sex (estimate, 2.502) were directly associated with better cognition after stroke. Higher education level was associated with better cognition directly (estimate, 1.341) and indirectly (estimate, 0.227) through stroke severity. The combination of hypertension decreased the magnitude of the negative association between atrial fibrillation and cognition (estimate, from -4.092 to -3.580).

Conclusion

This is the first Chinese study exploring the moderated and mediating associations between cardiovascular risk factors, stroke severity, and cognitive function after stroke. Age, female sex, and atrial fibrillation were directly associated with lower cognition after stroke. The combination of hypertension might have a positive effect on cognition.

Right ventricle in heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) affects half of all patients with heart failure. While previously neglected, the right ventricle (RV) has sparked interest in recent years as a means for better understanding this condition and as a potential therapeutic target.

Right ventricular dysfunction (RVD) is present in 4%–50% of patients with HFpEF. The RV is intimately connected to the pulmonary circulation, and pulmonary hypertension is commonly implicated in the pathophysiology of RVD. The development of RVD in HFpEF may also be driven by comorbidities, such as chronic obstructive pulmonary disease, obesity, obstructive sleep apnoea and atrial fibrillation. The evaluation of RVD is particularly challenging due to anatomical and structural factors, as well as unique physiological characteristics of this chamber like load and interventricular dependency. Fractional area change, tricuspid annular plane systolic excursion and tricuspid annular systolic velocity are commonly used measurements of RV function. Speckle tracking echocardiography and cardiac magnetic resonance (CMR) are also gaining attention as important tools for the assessment of RV structure, fibre deformation and systolic performance. Further research is needed to confirm the utility and prognostic significance of RV [18F]fluorodeoxyglucose (FDG) positron emission tomography imaging as FDG accumulation is suggested to increase with progressive RVD. Targeted pharmacotherapy with phosphodiesterase inhibitors, guanylate–cyclase stimulators, nitrates and inhaled inorganic nitrites have yet to demonstrate improvement in RVD, compelling the need for evaluation and discovery of novel pharmacological interventions for this entity.