Silent Stroke

Postoperative neurocognitive disorders (PND) are serious and common complications after surgery, especially in elderly patients. These disorders can affect cognitive functions for years, deteriorating quality of life and increasing hospital stays and medical costs. Diagnosing PND is challenging due to their varied manifestations, such as memory and attention problems, and the lack of standardized criteria and biomarkers. One well-studied form of PND is postoperative delirium (POD). According to the ICD-10, POD is an organic cerebral syndrome characterized by disturbances in consciousness, attention, perception, and other cognitive functions. Researchers suggest that POD development involves a combination of predisposing and precipitating factors. Electroencephalography (EEG) has been used in anesthesiology to assess anesthesia depth and intraoperative awareness. Modern EEG analysis methods, like spectral analysis, offer new ways to evaluate patients' neurophysiological states. Studies show that EEG monitoring can predict complications such as intraoperative stroke and delirium, particularly in cardiothoracic and neurosurgical operations. The relationship between EEG patterns and POD is not well understood. Specific EEG patterns may indicate the risk of POD, aiding in the identification of risk factors and prevention methods. This could help anesthesiologists and surgeons optimize their approaches, reducing the risk of cognitive complications.

The CBI registry is a prospective, interdisciplinary, multimodal observational registry of patients with covert brain infarction. Methods: A standardized workup in analogy to manifest ischemic stroke including cerebral MRI, long-term rhythm monitoring (3 x 7 days ECG), echocardiography, laboratory work-up and risk factor assessment as well as noninvasive angiography of the cervical and intracranial arteries will be performed.

Arterial Fibrillation (AF) is well-recognized as a cause for cryptogenic Acute Ischemic Stroke (AIS) and is associated with Silent Brain Infarction (SBI). However, the role of AF in the formation of lesions (SBIs) is less well established than its role in AIS and needs clarification. The investigators hypothesize that continuous rhythm monitoring will yield a similar incidence of AF diagnosis in patients with SBI as compared to patients with cryptogenic AIS. The primary objective is to assess the cumulative incidence of AF diagnosis at 24 months in patients with SBI.

The study aims to assess the effect of the use of neuroprotection in transcutaneous occlusion of the left atrial appendage in patients with atrial fibrillation on the risk of perioperative silent brain ischemia and associated cognitive impairment and depression.