Neue klinische und bildgebende Befunde zur transitorisch ischämischen Attacke

Zusammenfassung

Bisher werden Patienten mit transitorisch ischämischer Attacke (TIA) wegen ihrer nur flüchtigen fokal-neurologischen Symptomatik häufig einer verzögerten und inkompletten Diagnostik zugeführt. In dieser Übersicht werden neue klinische und bildgebende Befunde vorgestellt, die deutlich machen, dass die TIA einen neurologischen Notfall darstellt. So ist das Risiko für einen Schlaganfall nach einer TIA hoch, insbesondere in der Akutphase (3,9 bis 5,5% innerhalb von 48 Stunden, 10,5 bis 12% innerhalb von 1 Monat) und erfordert eine rasche ätiologische Abklärung, ein initiales Monitoring und die Einleitung einer risikofaktorenorientierten Sekundärprävention, da effektive Behandlungsoptionen (z.B. TEA bei Karotisstenose, Antikoagulation bei Vorhofflimmern, Thrombozytenfunktionshemmer) zur Verfügung stehen. Das Kurzzeitrisiko nach einer TIA kann durch einen neuen klinischen Score (ABCD-Score) einfach und schnell abgeschätzt werden. Moderne kernspintomographische Verfahren ermöglichen es, TIA-Patienten zu selektieren, die eine instabile Verlaufsform und damit ein hohes Akutrezidivrisiko aufweisen. Besonders gefährdet sind TIA-Patienten mit Läsionen in der diffusionsgewichteten Kernspintomographie und einer Symptomdauer >1 Stunde bzw. dem Nachweis intrakranieller Stenosen. Patienten mit TIA sind auch im Langzeitverlauf durch kardiale Komplikationen bedroht und benötigen eine langfristige Optimierung der Gefäßrisikofaktoren.

Summary

Up to now, patients with a transient ischemic attack (TIA) were often referred toa delayed and incomplete diagnostic and therapeutic workup because of the only transient nature of their symptoms. In this overview new clinical and imaging findings will be presented that underscore the concept that a TIA represents a neurological emergency. The stroke risk after a TIA is high, particularly during the acute phase (3.9 to 5.5% during the first 48 hours, 10.5 to 12% during one month) and requiresa rapid evaluation of the etiology, an initial monitoring of the patient, a risk factor oriented secondary prevention, because effective treatment options were available (e.g. CEA for carotid stenosis, anticoagulation for atrial fibrillation). The short time risk after a TIA can be estimated with an easy clinical score (ABCD score). New MRI techniques enable to select TIA patients with an unstable clinical course and an elevated acute risk for subsequent stroke. Particularly endangered are TIA patients with lesions seen in the diffusion-weighted MRI and a symptom duration of more than 1 hour or the detection of intracranial stenosis. Patients with TIA are threatened through cardiac complications during the long-term and need a sustained optimization of their cardiovascular risk factors.

Schlüsselwörter

Transiente ischämische Attacke - Schlaganfall - Risikostratifizierung - Bildgebung - Diagnostik

Keywords

Transient ischemic attack - stroke - risk stratification - cerebral imaging - diagnosis

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