A Large prolapsing left Atrial Appendage Thrombus in Sinus Rhythm - - PDF document

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A Large prolapsing left Atrial Appendage Thrombus in Sinus Rhythm

Sudish Lal Advanced Cardiology Trainee Dunedin Hospital

Disclosures: none

Case

• 69yr old male
• Past Medical History: OSA on CPAP, Asthma, Hypertension, CKD, L) THJR
• Presenting complaint: NYHA class III HF
• Investigations:
• ECG: SR, nil ischaemic changes
• Hs-TnT 32 ng/L, NT-proBNP 210pmol/L, Cr 150mmol/L
• FBC/LFT’s/Normal coagulation screen

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Diagnosis

• Ischaemic cardiomyopathy
• LV thrombus - akinetic apex
• Probable LAA thrombus

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Management Plan

• Warfarin commenced with heparin bridging
• Evidence based HF medications commenced
• Inpatient for a week to optimise medications – sinus rhythm

recorded throughout

• Repeat TTE

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• Discussed at cardio surgical meeting
• Surgical revascularisation

Management

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Post-op

• Uncomplicated recovery
• No evidence of AF
• Medications: Aspirin, Carvedilol, Spironolactone,

Candesartan Cardioembolic systemic embolus/stroke

• ~15 - 20million people worldwide have a stroke each

year

• 90% ischaemic vs 10% haemorrhagic stroke
• Emboli of cardiac origin accounts for 1/5 of all

ischaemic strokes

• Often associated with higher morbidity and mortality

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Cardiac Source of Emboli

• AF is the most common cardiac abnormality associated

with ischaemic strokes

• LAA source of emboli:
• 90% of cases with non-valvular AF
• 50% in valvular AF

LAA - Anatomy

• LAA is a complex structure, embryologic origin distinct from LA
• LAA is trabeculated, blind-ended projection; LA cavity is smooth walled
• 2 lobes 50%
• 3 lobes 25%
• 1 lobe 20%
• 4 lobes <5%

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LAA - Morphology

50% 19% 3% 30%

Lee ML et al. 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.

Beigel R et al. The Left Atrial Appendage: Anatomy, Function, and Noninvasive

• Evaluation. J Am Coll cardiol Img 2014;7:1251-65

Lee ML et al. 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.

LAA Morphology & Stroke Risk

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LA and LAA Dimension as Risk factors

• LA AP diameter OR 2.5
• LAA orifice area OR 1.38

Lee ML et al. 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.

LAA Flow Velocities in AF

• In AF decrease in LAA function is indicated by a decrease in Doppler flow velocities
• AF subgroups with normal vs low velocities

Lee ML et al. 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.

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LAA flow velocity in AF and risk of Thrombus

• Flow velocity <40cm/s
• Presence of SEC
• Velocities <20cm/s

Lee ML et al. 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.

LAA Thrombus in Sinus Rhythm

• Incidence of LA thrombus in

combination with SR ~0.1%

Agmon Y et al. Clinical and Echocardiographic Characteristics of Patients With Left Atrial Thrombus and Sinus Rhythm. Circulation. 2002;105:27-31

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LAA Thrombus in Sinus Rhythm

• “High-risk” factors identified
• Significant left-sided VHD
• Severe LV dysfunction
• Previous documentation of AF

Agmon Y et al. Clinical and Echocardiographic Characteristics of Patients With Left Atrial Thrombus and Sinus Rhythm. Circulation. 2002;105:27-31

Other Imaging modalities for assessing thrombus in LA/LAA

Romero J et al. Cardiac imaging for assessment of left atrial appendage stasis and thrombosis. Nat Rev Cardiol 2014;11:470-480

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CONCLUSION

• Thrombus within the LAA is very rare in sinus rhythm
• Factors independent of AF associated with increasing risk of LAA

thrombus are specific cardiac abnormalities and intrinsic LAA properties

• This case demonstrates the unexpected heterogeneous potential of LAA

thrombus formation in a patient in sinus rhythm

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