Background
Strokes occur in some patients with atrial fibrillation (AF), even when the CHA2DS2-VASc (congestive heart failure, hypertension, age >75 years, diabetes mellitus, prior
stroke or transient ischemic attack, vascular disease, age>65 years, female sex) score
is low.
Objective
We sought to determine the factors defining the residual stroke risk in patients with
AF and low CHA2DS2-VASc scores, with a particular focus on the hemodynamics and geometry of the left
atrial appendage (LAA).
Methods
From February 1, 2008 to December 31, 2012, 66 consecutive patients with nonvalvular
AF and a CHA2DS2-VASc score of 0 or 1 (except a point for the female sex) were enrolled. All patients
were admitted with a diagnosis of acute ischemic stroke. The control group consisted
of patients with nonvalvular AF without a history of stroke.
Results
The LAA orifice area was larger (4.35 ± 1.51 cm2 vs 2.83 ± 0.9 cm2; P < .001) and the LAA flow velocity was lower (41.9 ± 22.7 cm/s vs 54.4 ± 19.9 cm/s;
P < .001) in the stroke group than in the control group. Low LAA flow velocity (<40
cm/s) and large LAA orifice area (>4 cm2) were independent predictors of stroke. Patients with an LAA flow velocity of <40
cm/s and an LAA orifice of >4.0 cm2 had a markedly higher odds ratio (odds ratio 10.9; 95% confidence interval 3.0–40.0;
P < .001) of stroke than did those with preserved LAA flow velocity and smaller LAA
orifice.
Conclusion
Even in patients with low CHA2DS2-VASc scores, the presence of both decreased LAA flow velocity and increased LAA orifice
size was associated with a high odds ratio of stroke. Future large prospective studies
are needed to assess whether these patients should receive anticoagulants.
Keywords
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References
- 2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS.Eur Heart J. 2016; 37: 2893-2962
- 2014 AHA/ACC/HRS guideline 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 Heart Rhythm Society.J Am Coll Cardiol. 2014; 64: e1-e76
- Left atrial appendage flow velocity as a quantitative surrogate parameter for thromboembolic risk: determinants and relationship to spontaneous echo contrast and thrombus formation—a transesophageal echocardiographic study in 500 patients with cerebral ischemia.J Am Soc Echocardiogr. 2005; 18: 1366-1372
- Stroke Prevention in Atrial Fibrillation III Investigators. Transesophageal echocardiographic correlates of clinical risk of thromboembolism in nonvalvular atrial fibrillation.J Am Coll Cardiol. 1998; 31: 1622-1626
- A transesophageal echocardiographic study on risk factors for stroke in elderly patients with atrial fibrillation: a comparison with younger patients.Chest. 2001; 120: 840-846
- Assessment of left atrial appendage function by biplane transesophageal echocardiography in patients with nonrheumatic atrial fibrillation: identification of a subgroup of patients at increased embolic risk.J Am Coll Cardiol. 1994; 23: 599-607
- Secondary prognosis after cardioembolic stroke of atrial origin: the role of left atrial and left atrial appendage dysfunction.Clin Cardiol. 2003; 26: 269-274
- Impact of increased orifice size and decreased flow velocity of left atrial appendage on stroke in nonvalvular atrial fibrillation.Am J Cardiol. 2014; 113: 963-969
- Does the left atrial appendage morphology correlate with the risk of stroke in patients with atrial fibrillation? Results from a multicenter study.J Am Coll Cardiol. 2012; 60: 531-538
- Left atrial appendage morphology and silent cerebral ischemia in patients with atrial fibrillation.Heart Rhythm. 2014; 11: 2-7
- 2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines.Circulation. 2013; 128: e240-e327
- 2014 evidence-based guideline for the management of high blood pressure in adults: report from the panel members appointed to the Eighth Joint National Committee (JNC 8).JAMA. 2014; 311: 507-520
- Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III).JAMA. 2001; 285: 2486-2497
- Pulmonary vein diameter, cross-sectional area, and shape: CT analysis.Radiology. 2005; 235: 43-49
- Assessment of intra- and interobserver variability of pulmonary vein measurements from CT angiography.Acad Radiol. 2004; 11: 1211-1218
- Index for rating diagnostic tests.Cancer. 1950; 3: 32-35
- Left atrial enlargement is an independent predictor of stroke and systemic embolism in patients with non-valvular atrial fibrillation.Sci Rep. 2016; 6: 31042
- CHA2DS2-VASc score, left atrial size and atrial fibrillation as stroke risk factors in the Tromsø Study.Open Heart. 2016; 3: e000439
- Mechanisms of thrombogenesis in atrial fibrillation: Virchow's triad revisited.Lancet. 2009; 373: 155-166
- Relationship between left atrial appendage morphology and stroke in patients with atrial fibrillation.Heart Rhythm. 2013; 10: 1843-1849
- Left atrial appendage morphology and thromboembolic risk after catheter ablation for atrial fibrillation.Heart Rhythm. 2014; 11: 2239-2246
- Why is left atrial appendage morphology related to strokes? An analysis of the flow velocity and orifice size of the left atrial appendage.J Cardiovasc Electrophysiol. 2015; 26: 922-927
- Correlation between left atrial appendage morphology and flow velocity in patients with paroxysmal atrial fibrillation.Eur Heart J Cardiovasc Imaging. 2016; 17: 59-66
- Bias in case-control studies: a review.J Epidemiol Community Health. 1990; 44: 179-186
Article info
Publication history
Published online: May 27, 2017
Footnotes
This research was supported by a CMB-Yuhan research grant of Yonsei University College of Medicine (6-2015-0173), Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (NRF-2017R1A2B3003303) and grants from the Korean Healthcare technology R&D project funded by the Ministry of Health & Welfare (HI16C0058, HI15C1200).
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