Clinical utility of evaluating intracranial artery stenosis and silent brain infarction to predict the presence of subclinical coronary artery disease in ischemic stroke patients

Stroke Related Brain-Heart Crosstalk: Pathophysiology, Clinical Implications, and Underlying Mechanisms

The emergence of acute ischemic stroke (AIS) induced cardiovascular dysfunctions as a bidirectional interaction has gained paramount importance in understanding the intricate relationship between the brain and heart. Post AIS, the ensuing cardiovascular dysfunctions encompass a spectrum of complications, including heart attack, congestive heart failure, systolic or diastolic dysfunction, arrhythmias, electrocardiographic anomalies, hemodynamic instability, cardiac arrest, among others, all of which are correlated with adverse outcomes and mortality. Mounting evidence underscores the intimate crosstalk between the heart and the brain, facilitated by intricate physiological and neurohumoral complex networks. The primary pathophysiological mechanisms contributing to these severe cardiac complications involve the hypothalamic-pituitary-adrenal (HPA) axis, sympathetic and parasympathetic hyperactivity, immune and inflammatory responses, and gut dysbiosis, collectively shaping the stroke-related brain-heart axis. Ongoing research endeavors are concentrated on devising strategies to prevent AIS-induced cardiovascular dysfunctions. Notably, labetalol, nicardipine, and nitroprusside are recommended for hypertension control, while β-blockers are employed to avert chronic remodeling and address arrhythmias. However, despite these therapeutic interventions, therapeutic targets remain elusive, necessitating further investigations into this complex challenge. This review aims to delineate the state-of-the-art pathophysiological mechanisms in AIS through preclinical and clinical research, unraveling their intricate interplay within the brain-heart axis, and offering pragmatic suggestions for managing AIS-induced cardiovascular dysfunctions.

Association of Thymidylate Synthase (TS) Gene Polymorphisms with Incidence and Prognosis of Coronary Artery Disease

Coronary artery disease (CAD) is a prevalent cardiovascular condition characterized by the accumulation of plaque within coronary arteries. While distinct features of CAD have been reported, the association between genetic factors and CAD in terms of biomarkers was insufficient. This study aimed to investigate the connection between genetic factors and CAD, focusing on the thymidylate synthase (TS) gene, a gene involved in DNA synthesis and one-carbon metabolism. TS plays a critical role in maintaining the deoxythymidine monophosphate (dTMP) pool, which is essential for DNA replication and repair. Therefore, our research targeted single nucleotide polymorphisms that could potentially impact TS gene expression and lead to dysfunction. Our findings strongly associate the TS 1100T>C and 1170A>G genotypes with CAD susceptibility. We observed that TS 1100T>C polymorphisms increased disease susceptibility in several groups, while the TS 1170A>G polymorphism displayed a decreasing trend for disease risk when interacting with clinical factors. Furthermore, our results demonstrate the potential contribution of the TS 1100/1170 haplotypes to disease susceptibility, indicating a synergistic interaction with clinical factors in disease occurrence. Based on these findings, we propose that polymorphisms in the TS gene had the possibility of clinically useful biomarkers for the prevention, prognosis, and management of CAD in the Korean population.

Features of Antithrombotic Therapy in Patients with Multifocal Arterial Disease

Multifocal arterial injury is common in patients with atherosclerotic cardiovascular diseases and is associated with increased risk of cardiovascular complications and death. Administration of more intensive antithrombotic therapy, particularly combinations of acetylsalicylic acid and a "vascular" dose of rivaroxaban, in patients with multifocal arterial injury is characterized by a beneficial ratio of efficiency and safety due to a pronounced decrease in the risk of cardiovascular complications. Detection of peripheral artery diseases in patients with ischemic heart disease and atherosclerotic cerebrovascular pathology makes it possible to improve the risk stratification, optimize the diagnostic tactics and clarify indications for more intensive antithrombotic therapy.

Features of Risk Stratification, Diagnosis and Secondary Prevention in Patients with Multifocal Arterial Disease. Part 1: Risk Stratification and Diagnosis

Multifocal arterial disease is common in patients with atherosclerotic cardiovascular disease and is associated with an increased risk of cardiovascular complications and death. The possibility of improving the prognosis of patients with multifocal arterial disease is associated with a more efficient diagnosis of both the underlying disease and obstructive atherosclerotic lesions of other localizations and with a more intensive secondary prevention. According to observational studies, the presence of significant stenoses of the carotid arteries and, especially, lower extremities arterial disease can be predictorы of similar lesions in other vascular beds and their detection with screening methods available in clinical practice allows improvement of the diagnosis in patients with suspected coronary artery disease. On the other hand, screening of lower extremities artery diseases in patients with acute coronary syndrome can clarify indications for the use of invasive diagnostic and treatment strategy, in patients with chronic coronary artery disease it can justify more aggressive approaches to secondary prevention.

Quantifying the risk of heart disease following acute ischaemic stroke: a meta-analysis of over 50,000 participants

OBJECTIVE

Following an acute stroke, there is a high risk of recurrence. However, the leading cause of mortality following a stroke is due to coronary artery disease (CAD) and myocardial infarction (MI) but that risk has not been robustly quantified. We sought to reliably quantify the risk of ischaemic heart disease (IHD) in patients presenting with acute ischaemic stroke (AIS) in the absence of a known cardiac history.

SETTING

A meta-analysis study. PubMed, MEDLINE, EMBASE and Google Scholar were searched for potential studies up to October 2015. Included studies reported an acute cerebral ischaemic event and followed for CAD or MI within 1 year in patients without known IHD. Using arcsine transformed proportions for meta-analysis, studies were combined using a generic inverse variance random-effects model to calculate the pooled standardised mean difference and 95% CIs. These were interpreted as the percentage prevalence of CAD or incidence of MI following AIS.

RESULTS

17 studies with 4869 patients with AIS demonstrated a mean average of asymptomatic CAD in 52%. Anatomical methods of CAD detection revealed a prevalence of asymptomatic ≥ 50% coronary stenosis in 32% (95% CI 19% to 47%; p<0.00001). 8 studies with 47229 patients with ischaemic stroke revealed an overall risk of MI in the year following stroke of 3% (95% CI 1% to 5%; p<0.00001) despite the absence of any cardiac history.

CONCLUSIONS

One-third of patients with ischaemic stroke with no cardiac history have more than 50% coronary stenosis and 3% are at risk of developing MI within a year. Our findings provide a reliable quantitative measure of the risk of IHD following AIS in patients with no cardiac history.

Intracranial atherosclerosis

Atherosclerotic disease often involves the intracranial arteries including those encased by cranial bones and dura, and those located in the subarachnoid space. Age, hypertension, and diabetes mellitus are independent risk factors for intracranial atherosclerosis. Intracranial atherosclerosis can result in thromboembolism with or without hypoperfusion leading to transient or permanent cerebral ischaemic events. High rates of recurrent ischaemic stroke and other cardiovascular events mandate early diagnosis and treatment. Present treatment is based on a combination of antiplatelet drugs, optimisation of blood pressure and LDL cholesterol values, and intracranial angioplasty or stent placement, or both, in selected patients.

Risk factors associated with ischemic heart disease occurence in acute ischemic stroke patients

AIMS

At specific time periods following ischemic stroke (IS), acute coronary syndrome as ischemic heart disease (IHD) represents a higher risk of death than IS. Not all IS patients can undergo specific examination for IHD detection. The aim of this study was to assess exclusive risk factors (RFs) associated with IHD occurrence in IS patients. Knowledge of these RFs should help in stratifying IS patients for IHD detection.

MATERIALS AND METHODS

This was a hospital-based, retrospective, single centre study. The sample consisted of 192 consecutive IS patients, divided into two subgroups - Subgroup 1 (54 patients without IHD; 55.6% males; 63.1 ± 11.8 years) and Subgroup 2 (138 patients with IHD; 39.1% males; 76.3 ± 9.6 years). The following factors were identified: age; sex; presence of arterial hypertension, atrial fibrillation, diabetes mellitus; plasma levels of total cholesterol, triglycerides, low-density cholesterol, high-density cholesterol; body mass index; presence of carotid plaques. Logistic regression analysis was used for statistical evaluation.

RESULTS

Of all identified risk factors only age (OR=1.109; 95% CI: 1.069 - 1.150, P=0.001) and the presence of arterial hypertension (OR=6.298; 95% CI: 2.215 - 17.905, P=0.003) were exclusively and significantly associated with the presence of IHD in IS patients.

CONCLUSIONS

Age and arterial hypertension may be exclusive risk factors associated with IHD in IS patients.

White matter lesions and intra-arterial thrombolysis

The aim of the study was to assess the influence of white matter lesions in patients with acute ischemic stroke treated with intra-arterial thrombolysis (IAT). From September 2003 to January 2010, we treated 400 patients with IAT at our institution. Of these patients, 292 were evaluated with MRI scans and included in this observational study. Clinical data were collected prospectively. Outcome after 3 months was measured with the modified Rankin Scale (mRS); mRS 0-1 was considered as favorable outcome. White matter lesions were scored visually by two observers using the semiquantitative Scheltens and Fazekas scores. Logistic regression analysis was used to identify the association of white matter lesions and clinical outcome, recanalization, and cerebral hemorrhage. The severity of white matter lesions was inversely correlated with favorable outcome, survival and successful recanalization. White matter lesions were an independent predictor of outcome (OR 0.569, p = 0.007) and survival (OR 0.550, p = 0.018) and a weak but independent predictor for recanalization (OR 0.949, p = 0.038). Asymptomatic intracerebral bleeding after IAT was associated with white matter lesions in the basal ganglia in the univariate analysis (p = 0.036), but not after multivariable analysis. The severity of white matter lesions independently predicts clinical outcome and survival in patients treated with IAT. White matter lesions are also a weak but independent predictor for recanalization. Symptomatic intracranial bleeding after IAT are not associated with white matter lesions. Therefore, white matter lesions should not be considered as a contraindication against IAT.

Silent Brain Infarcts

Background and Purpose—

Silent brain infarcts (SBIs) have been recognized as common lesions in elderly subjects and their diagnosis relies on brain imaging. In this study, we aimed to evaluate the different MRI parameters and criteria used for their evaluation in the literature to better understand the variation across studies and related limitations.

Method—

Original MRI studies of SBI performed in human populations and reported in the English literature were reviewed. Analyses were restricted to population-based studies or studies in which at least 50 subjects with SBI were detected. The MRI parameters as well as the MRI criteria of SBI (size, signal characteristics, and criteria for differentiation of dilated Virchow-Robin spaces) were described and analyzed.

Result—

Magnetic field strength, slice thickness, and gap between slices greatly varied among the 45 articles included in this review. The MRI definition of SBI was inconsistent across studies. In half of them, SBI was defined as hypointense on T1 and hyperintense on T2-weighted images. Exclusion criteria for dilated Virchow-Robin spaces were used only in 7 studies.

Conclusions—

The variation in MRI characteristics and diagnostic criteria for SBI represent a major limitation for interpretation and comparison of data between studies. Efforts are needed to reach unified imaging criteria for SBI.