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DOI: 10.1055/s-2005-858787
© Georg Thieme Verlag KG Stuttgart · New York
MR-tomographische Evaluation der Inzidenz zerebraler Embolien bei Patienten mit Vorhofflimmern und linksatrialen Thromben
Long-Term Fate of Left Atrial Thrombi and Incidence of Cerebral Embolism under Continuous Anticoagulation TherapyPublication History
Publication Date:
07 December 2005 (online)
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Zusammenfassung
Ziel: Prospektive Evaluierung 1) der Prävalenz zerebraler Embolien mittels MRT- und Diffusionsbildgebung (DWI) bei Patienten (Pat.) mit neu diagnostiziertem Vorhofflimmern (AF) und gleichzeitigem Nachweis eines linksatrialen (LA-) Thrombus, 2) der Größenänderung der LA-Thromben innerhalb eines Jahres unter Antikoagulation mittels transösophagealer Echokardiographie (TEE) sowie 3) der Inzidenz neuer zerebraler Embolien unter 12-monatiger kontinuierlicher Antikoagulation. Methode: Untersucht wurden a) 32 Pat. mit neu diagnostiziertem AF, echokardiographischem Nachweis eines LA-Thrombus und Beginn einer antikoagulativen Therapie sowie b) eine Kontrollgruppe von 19 Pat. mit neu diagnostiziertem AF ohne LA-Thrombennachweis und äquivalenter Antikoagulationstherapie. Prospektiv und seriell wurden in beiden Gruppen durchgeführt: a) eine MRT-/DWI des Hirns zur Detektion zerebraler Embolien (Wochen 0, 4, 8, 12, 20, 28, 36, 44, and 52), b) eine TEE zur Größenbestimmung der LA-Thromben (Wochen 0 und 52) und c) eine neurologische Statuserhebung (Wochen 0, 20 und 52). Ergebnisse: In der Studiengruppe (AF mit LA-Thrombus) zeigten 11 von 32 Pat. (34 %) akute (n = 8) oder ältere (n = 3) zerebrale Embolien in der initialen MRT. Im einjährigen Verlauf unter Antikoagulation wurden bei 4/32 Pat. (13 %, davon n = 2/4 Pat. neurologisch symptomatisch) mittels MRT-/DWI neue zerebrale Embolien (n = 12) nachgewiesen. In der Kontrollgruppe (AF ohne LA-Thrombus) wurden sowohl in der initialen MRT (n = 1/19, 5 %) als auch im 12-Monats-Verlauf (n = 0/19, 0 %) signifikant (p < 0,01) weniger zerebrale Embolien detektiert. Nach einem Jahr waren noch 37 % der LA-Thromben echokardiographisch nachweisbar. Schlussfolgerung: 1) Die Inzidenz klinisch asymptomatischer zerebraler Embolien bei neu diagnostiziertem AF mit gleichzeitigem linksatrialem Thrombennachweis ist wesentlich höher als die Inzidenz klinisch manifester Embolien. 2) Neue zerebrale Embolien traten trotz therapeutischer Antikoagulation bei 13 % der Pat. im Verlauf auf. 3) Nur 63 % der Vorhofthromben lösten sich unter 12-monatiger Antikoagulation vollständig auf.
Abstract
Purpose: Patients (pts.) with atrial fibrillation (AF) and atrial thrombi are known to have an increased risk for cerebral embolism. However, little is known about the clinical course of atrial thrombi and the incidence of cerebral embolism in those patients during anticoagulation therapy. The high sensitivity of MR imaging (MRI) including diffusion-weighted imaging (DWI) suggests that this technique could provide an improved estimate of cerebral embolism associated with the presence of left atrial thrombi. The aims of this prospective study were to evaluate 1) the prevalence of clinically silent and apparent cerebral embolism in pts. with newly diagnosed AF and atrial thrombi using MRI/DWI, 2) the long-term fate of atrial thrombi under continues anticoagulation therapy and 3) the incidence of cerebral embolism during a follow-up period of 12 months with continuous anticoagulation therapy. Materials and Methods: The study group consisted of 32 pts. with 1) newly diagnosed AF and evidence of left atrial (LA) thrombi detected by TEE and 2) a new start of anticoagulation therapy [International Normalized Ratio (INR) 2.0 - 3.0]. 19 pts. with 1) newly diagnosed AF and no evidence of atrial thrombi and 2) an equivalent anticoagulation regimen served as the control group. In both groups a) MRI/DWI studies of the brain (weeks 0, 4, 8, 12, 20, 28, 36, 44, and 52), b) transesophageal echocardiographic studies (TEE) for assessment of LA-Thrombi (weeks 0 and 52) and c) clinical neurological assessments (weeks 0, 20 and 52) were performed. Results: In the study group (AF and LA-Thrombi) 11 out of 32 pts. (34 %) displayed signs of acute (n = 8) or chronic (n = 3) cerebral embolism in the initial MRI studies. In 4 out of 32 pts. (13 %), MRI/DWI depicted new or additional cerebral emboli (n = 12) during the follow-up period despite continuous anticoagulation therapy. 2 (n = 2/4; 50 %) of these patients had clinically apparent neurological deficits. In the control group 1 out of 19 pts. (5 %) showed evidence of chronic cerebral embolism as assessed by MRI/DWI at the beginning of the study (week 0). No embolic cerebral lesions were detected during the 12-month follow-up. Within 12 months only 63 % (n = 20/32) of LA thrombi in the study group resolved completely under anticoagulation. Conclusion: 1. The incidence of clinically inapparent cerebral emboli in pts. with newly diagnosed AF and atrial thrombi is much higher than the incidence of clinically apparent emboli and has been underestimated in the past. 2. New cerebral embolism may occur even with continued effective anticoagulation therapy in 13 % of pts. 3. Only 63 % of atrial thrombi resolve completely within 12 months under anticoagulation therapy.
Key words
MR imaging - atrial fibrillation - atrial thrombi - cerebral embolism - cerebral infarction - diffusion-weighted imaging
Literatur
- 1 Ferro J M. Atrial fibrillation and cardioembolic stroke. Minerva Cardioangiol. 2004; 177 111-124
- 2 Hart R G, Halperin J L, Pearce L A. et al . Lessons from stroke prevention in atrial fibrillation trials. Ann Intern Med. 2003; 177 831-838
- 3 Wolf P A, Abbott R D, Kannel W B. et al . Atrial fibrillation as an indipendent risk factor for stroke: the Framingham Study. Stroke. 1991; 177 983-988
- 4 Gonzalez R G, Schaefer P W, Buonanno. et al . Diffusion-weighted MR imaging: diagnostic accuracy in patients imaged within 6 hours of stroke symptom onset. Radiology. 1999; 177 155-162
- 5 Fuster V, Ryden L E, Singer R W. et al . ACC/AHA/ESC guidelines for the management of patients with atrial fibrillation. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines and Policy Conferences. Eur Heart J. 2001; 177 1852-1923
- 6 Laupacis A, Albers G, Dalen J. et al . Antithrombotic therapy in atrial fibrillation. Chest. 1995; 177 352-359
- 7 Hylek E M, Go A S, Chang Y. et al . Effect of intensity of oral anticoagulation on stroke severity and mortality in atrial fibrillation. N Engl J Med. 2003; 177 1019-1026
- 8 Go A D, Hylek E M, Phillips K A. et al . Prevalence of diagnosed atrial fibrillation in adults: national implications for rhythm management and stroke prevention: the Anticoagulation and Risk Factors in Atrial Fibrillation (ATRIA) Study. Jama. 2001; 177 2370-2375
- 9 Feinberg W M, Blackshear J L, Laupacis A. et al . Prevalence, age distribution, and gender of patients with atrial fibrillation. Analysis and implications. Arch Intern Med. 1995; 177 469-473
- 10 Mattle H P, Schwerzmann M, Seiler C. Vorhofflimmern und Hirninfarkt. Ther Umsch. 2003; 177 527-534
- 11 Benjamin E J, Wolf P A, D’Agostino R B. et al . Impact of atrial fibrillation on the risk of death: the Framingham Heart Study. Circulation. 1998; 177 946-952
- 12 Fiehler J T, Kucinski T, Zeumer H. Das Schlaganfall-MRT: Pathophysiologie, Potenzial und Perspektiven. Fortschr Röntgenstr. 2004; 177 313-323
- 13 Moseley M E, Kucharczyk J, Mintorovitch J. et al . Diffusion-weighted MR imaging of acute stroke: correlation with T2-weighted and magnetic susceptibility-enhanced MR imaging in cats. AJNR Am J Neuroradiol. 1990; 177 423-429
- 14 Warach S, Gaa J, Siewert B. et al . Acute human stroke studied by whole brain echo planar diffusion-weighted magnetic resonance imaging. Ann Neurol. 1995; 177 231-241
- 15 Sartor K, Hartmann M, Fiebach J. et al . Normale und pathologische Wasserdiffusion im Gehirn. Fortschr Röntgenstr. 2003; 177 1317-1329
- 16 Kucharczyk J, Vexler Z S, Roberts T P. et al . Echo-planar perfusion-sensitive MR imaging of acute cerebral ischemia. Radiology. 1993; 177 711-717
- 17 Chien D, Kwong K K, Gress D R. et al . MR diffusion imaging of cerebral infarction in humans. AJNR Am J Neuroradiol. 1992; 177 1097-1102
- 18 Mintorovitch J, Yang G Y, Shimizu H. et al . Diffusion-weighted magnetic resonance imaging of acute focal cerebral ischemia: comparison of signal intensity with changes in brain water and Na+,K(+)-ATPase activity. J Cereb Blood Flow Metab. 1994; 177 332-336
- 19 Matsumo K, Lo E H, Pierce A R. et al . Role of vasogenic edema and tissue cavitation in ischemic evolution on diffusion-weighted imaging: comparison with multiparameter MR and immunohistochemistry. AJNR Am J Neuroradiol. 1995; 177 1107-1115
- 20 Schaefer P W, Grant P E, Gonzalez R G. Diffusion-weighted MR imaging of the brain. Radiology. 2000; 177 331-345
- 21 Wick M, Nagatomo Y, Prielmeier F. et al . Alteration of intracellular metabolite diffusion in rat brain in vivo during ischemia and reperfusion. Stroke. 1995; 177 1930-1933
- 22 Duong T Q, Ackerman J J, Ying H S. et al . Evaluation of extra- and intracellular apparent diffusion in normal and globally ischemic rat brain via 19F NMR. Magn Reson Med. 1998; 177 1-13
- 23 Marks M P, de Crespigny A, Lentz D. et al . Acute and chronic stroke: navigated spin-echo diffusion-weighted MR imaging. Radiology. 1996; 177 403-408
- 24 Geijer B, Lindgren A, Brockstedt S. et al . Persistent high signal on diffusion-weighted MRI in the late stages of small cortical and lacunar ischaemic lesions. Neuroradiology. 2001; 177 115-122
- 25 Romero J M, Schaefer P W, Grant P E. et al . Diffusion MR imaging of acute ischemic stroke. Neuroimaging Clin N Am. 2002; 177 35-53
- 26 Heiland S, Sartor K. Magnetresonanztomographie beim Schlaganfall - Methodische Grundlagen und klinische Anwendung. Fortschr Röntgenstr. 1999; 177 3-14
- 27 Stollberger C, Chnupa P, Abzieher C. et al . Mortality and rate of stroke or embolism in atrial fibrillation during long-term follow-up in the embolism in left atrial thrombi (ELAT) study. Clin Cardiol. 2004; 177 40-46
- 28 Bernhardt P, Schmidt H, Hammerstingl C. et al . Fate of left atrial thrombi in patients with atrial fibrillation determined by transesophageal echocardiography and cerebral magnetic resonance imaging. Am J Cardiol. 2004; 177 801-804
- 29 Hohnloser S H, Kuck K H, Lilienthal J. Rhythm or rate control in atrial fibrillation -Pharmacological Intervention in Atrial Fibrillation (PIAF): a randomised trial. Lancet. 2000; 177 1789-1794
- 30 Van Gelder I C, Hagens V E, Bosker H A. et al . A comparison of rate control and rhythm control in patients with recurrent persistent atrial fibrillation. N Engl J Med. 2002; 177 1834-1840
- 31 Wyse D G, Waldo A L, DiMarco J P. et al . A comparison of rate control and rhythm control in patients with atrial fibrillation. N Engl J Med. 2002; 177 1825-1833
- 32 Artang R, Vidaillet H. Alternatives to warfarin for thromboembolism prophylaxis in nonrheumatic atrial fibrillation. J Interv Card Electrophysiol. 2004; 177 33-44
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