Acute Myocardial Infarction and Risk of Cognitive Impairment and Dementia: A Review.

Cognitive impairment (CI) shares common cardiovascular risk factors with acute myocardial infarction (AMI), and is increasingly prevalent in our ageing population. Whilst AMI is associated with increased rates of CI, CI remains underreported and infrequently identified in patients with AMI. In this review, we discuss the evidence surrounding AMI and its links to dementia and CI, including pathophysiology, risk factors, management and interventions. Vascular dysregulation plays a major role in CI, with atherosclerosis, platelet activation, microinfarcts and perivascular inflammation resulting in neurovascular unit dysfunction, disordered homeostasis and a dysfunctional neurohormonal response. This subsequently affects perfusion pressure, resulting in enlarged periventricular spaces and hippocampal sclerosis. The increased platelet activation seen in coronary artery disease (CAD) can also result in inflammation and amyloid-ß protein deposition which is associated with Alzheimer's Dementia. Post-AMI, reduced blood pressure and reduced left ventricular ejection fraction can cause chronic cerebral hypoperfusion, cerebral infarction and failure of normal circulatory autoregulatory mechanisms. Patients who undergo coronary revascularization (percutaneous coronary intervention or bypass surgery) are at increased risk for post-procedure cognitive impairment, though whether this is related to the intervention itself or underlying cardiovascular risk factors is debated. Mortality rates are higher in dementia patients with AMI, and post-AMI CI is more prevalent in the elderly and in patients with post-AMI heart failure. Medical management (antiplatelet, statin, renin-angiotensin system inhibitors, cardiac rehabilitation) can reduce the risk of post-AMI CI; however, beta-blockers may be associated with functional decline in patients with existing CI. The early identification of those with dementia or CI who present with AMI is important, as subsequent tailoring of management strategies can potentially improve outcomes as well as guide prognosis.

Multimodal Cardiac Imaging in the Assessment of Patients Who Have Suffered a Cardioembolic Stroke: A Review.

Cardioembolic strokes account for 20-25% of all ischaemic strokes, with their incidence increasing with age. Cardiac imaging plays a crucial role in identifying cardioembolic causes of stroke, with early and accurate identification affecting treatment, preventing recurrence, and reducing stroke incidence. Echocardiography serves as the mainstay of cardiac evaluation. Transthoracic echocardiography (TTE) is the first line in the basic evaluation of structural heart disorders, valvular disease, vegetations, and intraventricular thrombus. It can be used to measure chamber size and systolic/diastolic function. Trans-oesophageal echocardiography (TOE) yields better results in identifying potential cardioembolic sources of stroke and should be strongly considered, especially if TTE does not yield adequate results. Cardiac computed tomography and cardiac magnetic resonance imaging provide better soft tissue characterisation, high-grade anatomical information, spatial and temporal visualisation, and image reconstruction in multiple planes, especially with contrast. These techniques are useful in cases of inconclusive echocardiograms and can be used to detect and characterise valvular lesions, thrombi, fibrosis, cardiomyopathies, and aortic plaques. Nuclear imaging is not routinely used, but it can be used to assess left-ventricular perfusion, function, and dimensions and may be useful in cases of infective endocarditis. Its use should be considered on a case-by-case basis. The accuracy of each imaging modality depends on the likely source of cardioembolism, and the choice of imaging approach should be tailored to individual patients.

An Asian Perspective on Gender Differences in In-Hospital and Long-Term Outcome of Cardiac Mortality and Ischemic Stroke after Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction.

OBJECTIVES: Gender differences historically exist in cardiovascular disease, with women experiencing higher rates of major adverse cardiovascular events. We investigated these trends in a contemporary Asian cohort, examining the impact of gender differences on cardiac mortality and ischemic stroke after primary percutaneous coronary intervention (PPCI) for ST elevation myocardial infarction (STEMI). MATERIALS AND METHODS: We analysed 3971 consecutive patients who underwent primary PCI for STEMI retrospectively. The primary outcome was cardiac mortality and ischemic stroke in-hospital, at one year and on longer-term follow up (median follow up 3.62 years, interquartile range 1.03-6.03 years). RESULTS: There were 580 (14.6%) female patients and 3391 (85.4%) male patients. Female patients were older and had higher prevalence of hypertension, diabetes, previous strokes, and chronic kidney disease. Cardiac mortality was higher in female patients during in-hospital (15.5% vs. 6.2%), 1-year (17.4% vs. 7.0%) and longer term follow up (19.9% vs. 8.1%, log-rank test: p < 0.001). Similarly, females had higher incidence of ischemic stroke at in-hospital (2.6% vs. 1.0%), 1-year (3.6% vs. 1.4%) and in the longer-term (6.7% vs. 3.1%) as well (log-rank test: p < 0.001). Female gender remained an independent predictor of in-hospital cardiac mortality (HR 1.395, 95%CI 1.061-1.833, p=0.017) and on longer-term follow-up (HR 1.932 95%CI 1.212-3.080, p=0.006) even after adjusting for confounders. CONCLUSIONS: Females were at higher risk of in-hospital and long-term cardiac mortality and ischemic stroke after PPCI for STEMI. Future studies are warranted to investigate the role of aggressive management of cardiovascular risk factors and follow-up to improve outcomes in the females with STEMI.