J Cardiovasc Ultrasound.  2011 Jun;19(2):51-61. 10.4250/jcu.2011.19.2.51.

Role of Echocardiography in Atrial Fibrillation

• Kim TS
• Youn HJ

• KMID: 1980351
• DOI: http://doi.org/10.4250/jcu.2011.19.2.51

Abstract

Atrial fibrillation (AF) is most common arrhythmia and its prevalence appears to be increasing as the population ages. Echocardiography can play a key role in risk stratification and management of patients with AF. Transthoracic echocardiography allows rapid and comprehensive assessment of cardiac anatomical structure and function. Pulmonary vein flow monitoring using echocardiography has the potential to an increasing role in the evaluation of cardiac function and AF ablation procedures. Transesophageal echocardiography also provides accurate information about the presence of a thrombus in the atria and thromboembolic risk. The novel technique of intracardiac echocardiography has emerged as a popular and useful tool in the everyday practice of interventional electrophysiology. Other imaging modalities, such as computed tomography and magnetic resonance imaging have complementary roles in risk stratification and assessment of patients with AF. Echocardiography continues to be the foundation of clinical evaluation and management of AF.

Keyword

Atrial fibrillation; Transthoracic echocardiography; Transesophageal echocardiography

MeSH Terms

Arrhythmias, Cardiac
Atrial Fibrillation
Echocardiography
Echocardiography, Transesophageal
Electrophysiology
Humans
Magnetic Resonance Imaging
Prevalence
Pulmonary Veins
Thrombosis

Figure

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  Fig. 1 Biplane left atrial (LA) volume measurement in apical 4 chamber (A) and apical 2-chamber (B) views of transthoracic echocardiography. LV: left ventricle, LAA: left atrial appendage.

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  Fig. 2 Representative left atrial (LA) myocardial velocity using tissue Doppler image (TDI), strain rate (SR), and strain curves in a normal subject (A, B, and C, respectively) and a patient with atrial fibrillation (AF) (D, E, and F, respectively). The sample volume is placed at the mid-level of inter-atrial septum. In the patients with AF, no decrease in SR by atrial contraction was observed, but small phasic movements by the AF wave were recorded. Using TDI-derived velocity and SR parameters, it was found that the LA mechanical function was significantly decreased in AF as reflected by reduction in the S' and/or E' wave in the absence of the A' wave during late diastole. S' wave: ventricular systolic wave, E' wave: ventricular early diastolic wave, A' wave: late diastolic wave (atrial contraction).

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  Fig. 3 Pulsed wave Doppler study of transmitral inflow in atrial fibrillation. Arrow indicates early transmitral flow deceleration time (DT). E represents peak LV early diastolic filling velocity. Peak E velocity and DT vary depending on cardiac cycle length. LV: left ventricle.

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  Fig. 4 Tissue Doppler imaging of the septal mitral annular velocities (e') in a patient with atrial fibrillation. The measurements should be averaged over 5 to 10 cardiac cycles.

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  Fig. 5 Color M-mode, to calculate mitral inflow propagation velocity, is acquired from the apical 4-chamber view by placing a cursor over the center of mitral inflow and reducing the Nyquist limit for flow toward apex to a point when the central color turns blue.

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  Fig. 6 Pulmonary venous flow pattern demonstrated by transthoracic echocardiography in atrial fibrillation. Arrow indicates pulmonary venous diastolic deceleration time. S: peak systolic velocity, D: peak diastolic velocity.

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  Fig. 7 Transesophageal echocardiography can identify significant pul-monary vein (PV) stenosis. Pulsed-wave Doppler of PV inflow > 110 cm/s confirms hemodynamically significant stenosis. LA: left atrium, AO: aorta, LSPV: left superior pulmonary vein.

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  Fig. 8 Image of thrombus (arrow) within the left atrial appendage discovered on a transesophageal echocardiography. LA: left atrium, AO: aorta.

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  Fig. 9 Spontaneous echo contrast (*) swirling detected by transeso-phageal echocardiography in a patient with atrial fibrillation. LA: left atrium, RA: right atrium.

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  Fig. 10 Pulsed wave Doppler of the left atrial appendage with transesophageal echocardiography. This picture demonstrates the decreased emptying and filling velocities in patients with atrial fibrillation.

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  Fig. 11 Schematic flow chart of the transesophageal echocardiography-guided early cardioversion. *Long-term oral anticoagulation if stroke risk factors and/or risk of AF recurrence/presence of thrombus. AF: atrial fibrillation, LAA: left atrial appendage, UFH: unfractionated heparin, LMWH: low molecular weight heparin.

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  Fig. 12 The posterior view of computed tomography image shows three-dimensional information of anatomy of left atrium and pulmonary vein. LSPV: left superior pulmonary vein, RSPV: right superior pulmonary vein.

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