Cardiac Imaging After Ischemic Stroke or Transient Ischemic Attack.

PURPOSE OF REVIEW: Cardiac imaging after ischemic stroke or transient ischemic attack (TIA) is used to identify potential sources of cardioembolism, to classify stroke etiology leading to changes in secondary stroke prevention, and to detect frequent comorbidities. This article summarizes the latest research on this topic and provides an approach to clinical practice to use cardiac imaging after stroke. RECENT FINDINGS: Echocardiography remains the primary imaging method for cardiac work-up after stroke. Recent echocardiography studies further demonstrated promising results regarding the prediction of non-permanent atrial fibrillation after ischemic stroke. Cardiac magnetic resonance imaging and computed tomography have been tested for their diagnostic value, in particular in patients with cryptogenic stroke, and can be considered as second line methods, providing complementary information in selected stroke patients. Cardiac imaging after ischemic stroke or TIA reveals a potential causal condition in a subset of patients. Whether systematic application of cardiac imaging improves outcome after stroke remains to be established.

Cardiac imaging after ischemic stroke : Echocardiography, CT, or MRI?

About 20-25% of all ischemic strokes are of cardioembolic etiology, with atrial fibrillation and heart failure as the most common underlying pathologies. Diagnostic work-up by noninvasive cardiac imaging is essential since it may lead to changes in therapy, e.g., in-but not exclusively-secondary stroke prevention. Echocardiography remains the cornerstone of cardiac imaging after ischemic stroke, with the combination of transthoracic and transesophageal echocardiography as gold standard thanks to their high sensitivity for many common pathologies. Transesophageal echocardiography should be considered as the initial diagnostic tool when a cardioembolic source of stroke is suspected. However, to date, there is no proven benefit of transesophageal echocardiography-related therapy changes on the main outcomes after ischemic stroke. Based on the currently available data, cardiac computed tomography and magnetic resonance imaging should be regarded as complementary methods to echocardiography, providing additional information in specific situations; however, they cannot be recommended as first-line modalities.

Incidence of MRI-detected brain lesions and neurocognitive function after electrical cardioversion in anticoagulated patients with persistent atrial fibrillation.

BACKGROUND: After electrical cardioversion (eCV) in patients with atrial fibrillation (AF), the risk for clinically apparent cerebral thromboembolism is increased in the subsequent weeks. To date, there is little evidence on the incidence of acute brain lesions (ABL) detected with cerebral magnetic resonance imaging (MRI) after eCV, in particular in patients treated with the Non-Vitamin K Antagonist oral anticoagulants (NOAC). AIMS: The aim of this pilot study was to evaluate the incidence of MRI-detected ABL, as well as the neuro-cognitive function after eCV in patients with persistent AF using NOACs as compared to phenprocoumon. METHODS AND RESULTS: 50 consecutive patients with persistent AF (mean age 69.6±3.5years, 26 male) were evaluated in this prospective study. Cerebral 3Tesla MRI and neuro-cognitive assessment using the National Institutes of Health Stroke Scale (NIHSS) score and the Montreal Cognitive Assessment Test (MoCA) were performed in all patients within 24h before eCV and after a median follow-up duration of 14days (Q1: 13, Q3: 19days). Patients were treated with an OAC for at least 4weeks after eCV and according to the CHA2DS2-Vasc-score thereafter. Thirty-nine patients were treated with NOACs (Dabigatran 10/50 [20%], Apixaban 21/50 [42%] and Rivaroxaban 8/50 [16]) and 11/50 patients with Phenprocoumon (22%). No patient developed ABL on cerebral MRI at the 2-week follow-up. Neurological as well as cognitive function were similar before and 2weeks after eCV (NIHSS-score: p=0.35; MoCa score: p=0.21). CONCLUSION: Electrical CV in patients with persistent AF, in particular when treated with NOACs, carries a low risk for the development of MRI-detected ABL or neurocognitive decline. CLINICAL TRIALS REGISTRATION: GermanClinicalTrialsRegister number: DRKS00010460.

Thrombophilia screening in young patients with cryptogenic stroke. Prevalence of gene polymorphisms compared to healthy blood donors and impact on secondary stroke prevention.

UNLABELLED: The clinical relevance of thrombophilia screening in stroke patients is still a matter of debate, and descriptions of larger patterns of genetic variability are rare. We assessed the frequency of hereditary hypercoagulability in young patients with cryptogenic stroke (n = 44) and in healthy blood donors (n = 282) without prior cardiovascular event. Furthermore, we focused on the impact of thrombophilia screening on secondary stroke prevention. RESULTS: Compared to the control group (19-67 years; median 38.5 years; 64% women), there was a lower prevalence of the FVII-R353Q mutation (p = 0.033) in stroke patients (17-52 years; median 36 years; 59.1% women). Of note, the FVII-R353Q mutation lowers FVII plasma levels, probably reducing the risk of cardiovascular events. The prevalence of the remaining 13 gene polymorphisms did not differ significantly. However, the prevalence of FV Leiden mutation tended to be higher among stroke patients. CONCLUSION: Overall, extended screening for inherited thrombophilia had an impact on medical stroke prevention in every sixth patient with cryptogenic stroke.

Vascular risk factor awareness before and pharmacological treatment before and after stroke and TIA.

BACKGROUND AND PURPOSE: Educating the public to screen for vascular risk factors and have them treated is a major public health issue. We assessed the vascular risk factor awareness and frequency of treatment in a cohort of patients with cerebral ischaemia. METHODS: Data on awareness and pharmacological treatment of vascular risk factors before hospital admission of patients with confirmed ischaemic stroke/transient ischaemic attack (TIA) were analyzed. A follow-up questionnaire assessed the frequency of treatment 1 year after discharge and assessed non-adherence to antithrombotic medication. RESULTS: At time of stroke/TIA, individual awareness regarding existing hypertension, diabetes, hyperlipidemia and atrial fibrillation (AF) was 83%, 87%, 73% and 69% respectively (n = 558). Pharmacological treatment for hypertension, diabetes, hyperlipidemia and AF was being administered in 80%, 77%, 37% and 62% of patients aware of their conditions. The follow-up was completed by 383 patients (80% recall rate): of the patients with hypertension, diabetes, hyperlipidemia and AF, 89%, 78%, 45% and 86% were receiving risk factor targeted medication. This represents a significant increase concerning AF and hyperlipidemia. Non-adherence to recommended antithrombotics (15%) was higher in patients who had had a TIA. CONCLUSIONS: All risk factors leave room for improvement in screening and treatment efforts. Adherence to treatment is higher for hypertension and diabetes than for hyperlipidemia. Education efforts should bear in mind less well recognized risk factors.