Miika Korhonen BMBS, MSc, Presenter: Nothing to Disclose

Antti Tapani Muuronen BMedSc, Abstract Co-Author: Nothing to Disclose

Mika Haataja MD, Abstract Co-Author: Nothing to Disclose

Otso Arponen, Abstract Co-Author: Nothing to Disclose

Marja Hedman, Abstract Co-Author: Nothing to Disclose

Pekka Jakala, Abstract Co-Author: Nothing to Disclose

Petri J. Sipola MD, Abstract Co-Author: Nothing to Disclose

Pirjo Mustonen, Abstract Co-Author: Nothing to Disclose

Ritva Liisa Vanninen MD, Abstract Co-Author: Nothing to Disclose

Mikko Tapani Taina, Abstract Co-Author: Nothing to Disclose

Left atrial appendage (LAA) is the most typical origin for intracardiac thrombus formation when associated with atrial fibrillation (AF). There is controversy whether LAA morphology associates with increased stroke/TIA risk and, if it does, which morphological type increases the risk most. We used cardiac computed tomography (cCT) to examine LAA morphology and volume in suspected cardiogenic stroke/TIA patients without persistent AF.

The prospective study included 111 patients (74 males; mean age, 60 years) with suspected cardioembolic stroke/TIA without AF and 40 (21 males; mean age, 54 years) age and gender matched healthy control subjects. LAA volumes were quantified. Three observers in consensus classified LAAs into four morphology types (Cactus; ChickenWing; WindSock; CauliFlower) modified with a quantitative qualifier.

The proportions of LAA morphology types Cactus, ChickenWing, WindSock and CauliFlower were 5.0%, 37.5%, 35.0% and 22.5% in age and gender matched stroke/TIA patients and 20.0%, 10.0%, 67.5%, and 2.5% in controls, respectively. Distribution of morphology types differed significantly (P<0.01). Stroke patients also had decreased number of LAA lobes (P<0.01). In the whole stroke/TIA population the proportions of LAA morphology types Cactus, ChickenWing, WindSock and CauliFlower were 9.0%, 23.4%, 47.7%, and 19.8%. Patients with WindSock morphology had larger LAAs (P<0.01) and over half of patients with WindSock morphology had an enlarged LAA of >5.6 mL/m2.

LAA morphology differed significantly between stroke/TIA patients and healthy control subjects. ChickenWing LAA and fewer lobes were more common in stroke/TIA patients without chronic AF.

LAA morphologies associating with elevated stroke risk may suggest existence of paroxysmal atrial fibrillation and thus help targeting prolonged rhythm monitoring.

Korhonen, M, Muuronen, A, Haataja, M, Arponen, O, Hedman, M, Jakala, P, Sipola, P, Mustonen, P, Vanninen, R, Taina, M, Left Atrial Appendage Morphology Differs in Patients with Suspected Cardiogenic Stroke without Chronic Atrial Fibrillation.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14011507.html