Session number: 1118
Abstract title: Echocardiography in the Management of Stroke: Systematic Review and Cost-Utility Analysis
Author(s):
S Saha - Oregon Health & Science University Evidence-Based Practice Center
RT Meenan - Kaiser Permanente Center for Health Research
R Chou - Oregon Health & Science University Evidence-Based Practice Center
K Swarztrauber - Oregon Health & Science University Evidence-Based Practice Center
KP Krages - Oregon Health & Science University Evidence-Based Practice Center
M O'Keeffe-Rosetti - Kaiser Permanente Center for Health Research
M McDonagh - Kaiser Permanente Center for Health Research
BKS Chan - Oregon Health & Science University Evidence-Based Practice Center
MC Hornbrook - Kaiser Permanente Center for Health Research
M Helfand - Oregon Health & Science University Evidence-Based Practice Center
Objectives: Echocardiographic procedures, both transthoracic (TTE) and transesophageal (TEE), are commonly obtained in patients presenting with stroke, to detect treatable sources of cardioembolism, particularly intracardiac thrombi. We sought to determine the effectiveness and cost-effectiveness of this practice.
Methods: We searched relevant databases for studies addressing the yield and accuracy of TTE and TEE in identifying intracardiac thrombi, the harms associated with echocardiography (TEE), and the efficacy and safety of anticoagulant therapy in patients with stroke. We excluded data from patients with atrial fibrillation (AF), since anticoagulation is generally indicated in stroke patients with AF, regardless of echocardiographic findings. Applying evidence from our review, along with informed assumptions where necessary, we used semi-Markov decision models to assess the cost-effectiveness of TTE and TEE—-used either alone or in sequence, and either universally or selectively based on history of heart disease—-in a hypothetical cohort of 65 year-old men with stroke.
Results: Of 2,283 citations retrieved, 85 articles (18 on echocardiographic yield, 16 on diagnostic accuracy, 23 on TEE complications, and 28 on efficacy and safety of anticoagulation) met criteria for inclusion. The prevalence of echocardiographically identified thrombus in unselected patients with stroke (and without AF) was approximately 2%. Pooled estimates of sensitivity and specificity for TTE were 42% and 99%, respectively, for left atrial thrombus (LAT), and 77% and 95% for left ventricular thrombus (LVT). For TEE, sensitivity and specificity were 93% and 97% for LAT; we did not identify any studies of TEE accuracy in identifying LVT. Major complications (cardiovascular, pulmonary, and gastrointestinal events requiring treatment) associated with TEE occurred in 0.7% of patients, and the rate of peri-procedural death was 0.014%. We found insufficient evidence to allow conclusions regarding the efficacy of treatment in reducing the risk of future stroke associated with intracardiac thrombus in the absence of AF. When we assumed that anticoagulant therapy reduced this risk by 33% over one year, several strategies involving the selective use of TTE and TEE, based on presence or absence of heart disease, had an incremental cost-effectiveness ratio of less than $40,000 per quality-adjusted life year (QALY) saved. When the assumed benefit of anticoagulation was 10%, most echocardiographic strategies had a cost-effectiveness ratio exceeding $100,000 per QALY.
Conclusions: The benefits obtained from echocardiographic imaging in patients with stroke are uncertain. Under plausible assumptions, however, the cost-effectiveness of TTE and TEE in selected patients may be comparable to other commonly endorsed health care interventions.
Impact statement: There is insufficient evidence to support the routine or selective use of echocardiography in the management of stroke. Research is needed to clarify the risk of recurrent stroke associated with intracardiac thrombus (and other potential sources of cardioembolism), and the efficacy of anticoagulant therapy in reducing that risk.