The value of transesophageal echocardiography in the investigation and management of cryptogenic cerebral ischemia: a single-center experience

Predictive value of transesophageal echocardiography combined with contrast transthoracic echocardiography for embolic stroke of undetermined source

OBJECTIVE

In this study, we aimed to assess the predictive value of transesophageal echocardiography (TEE) combined with contrast transthoracic echocardiography (cTTE) for embolic stroke of undetermined source (ESUS).

METHODS

A total of 52 patients with ESUS were examined by TEE and cTTE. The detection rate of patent foramen ovale (PFO) and right-to-left shunt (RLS) grade were compared in patients with ESUS between cTTE alone and cTTE combined with TEE. The Risk of Paradoxical Embolism (RoPE) score, PFO diameter, and PFO length of patients with PFO-associated ESUS and non-PFO-associated ESUS were compared by cTTE alone and cTTE combined with TEE. The receiver operating characteristic (ROC) curve was utilized to determine the effect of RoPE score and PFO diameter on patients with PFO-associated ESUS.

RESULTS

The positive rate of PFO detected by cTTE alone (46.15%) was lower than that detected by cTTE combined with TEE (69.23%). The proportion of patients with RLS grade I + II + III detected by cTTE combined with TEE (69.23%) was higher than that detected by cTTE alone (46.15%). Both the RoPE score and PFO diameter were significantly greater in the patients with PFO-associated ESUS than in the patients with non-PFO-associated ESUS (p < .05). The combination of RoPE score and PFO diameter had the largest area under the ROC curve (AUC = 0.875), which was larger than the AUC alone of RoPE score (AUC = 0.819) and PFO diameter (AUC = 0.783) (p < .05).

CONCLUSION

The combination of cTTE and TEE is helpful to the diagnosis of ESUS patients caused by PFO and to judge the degree of RLS.

Utility of transesophageal echocardiography in the identification and treatment of occult mechanisms of cerebral infarction

Cryptogenic stroke comprises approximately 25% of all cases of ischemic stroke. The diagnostic evaluation of these patients remains a challenge in clinical practice. Transesophageal echocardiography (TEE) has been shown to have superior diagnostic accuracy in identifying potential cardioembolic sources of ischemic stroke when compared to transthoracic echocardiography (TTE). However, there has been inconsistent data on the management implications of these new cardiac findings. The addition of TEE to the comprehensive stroke evaluation will better identify potential cardiac sources of embolism (CSE) and will result in significant management changes. A prospective registry of consecutively admitted patients with acute ischemic stroke (1/1/2015-8/10/2020) was retrospectively queried. Patients 18 to 60 years of age with stroke due to mechanisms other than large or small vessel disease, or atrial fibrillation were eligible for inclusion. The primary outcome was any high-risk CSE identified on TEE following unrevealing TTE. Of the 2,404 consecutive stroke patients evaluated during the study period, 263 (11%) met inclusion criteria and the median age was 53 (IQR 46-57). TEE was performed in 108 patients (41%). A high-risk CSE was identified in 36 patients (33%), the majority of which were PFOs (n = 29). TEE led to a clinical management change in 14 patients (39%) after identification of a high-risk CSE; 6 underwent PFO closure and 8 had adjustment to their antithrombotic therapy. The addition of TEE to the comprehensive stroke evaluation led to the identification of a high-risk CSE in one in three patients resulting in significant management changes.

Association of Hypertensive Intracerebral Hemorrhage with Left Ventricular Hypertrophy on Transthoracic Echocardiography

INTRODUCTION

Arterial hypertension is the most frequent cause for spontaneous intracerebral hemorrhage (sICH) and may also cause left ventricular hypertrophy (LVH). We sought to analyze whether hypertensive sICH etiology is associated with LVH.

METHODS

We analyzed consecutive patients with sICH who were admitted to our tertiary stroke center during a four-year period and underwent transthoracic echocardiography (TTE) as part of the diagnostic work-up. We defined hypertensive sICH as typical localization of hemorrhage in patients with arterial hypertension and no other identified sICH etiology. We defined an increased end-diastolic interventricular septal wall thickness of ≥11 mm on TTE as a surrogate parameter for LVH.

RESULTS

Among 395 patients with sICH, 260 patients (65.8%) received TTE as part of their diagnostic work-up. The median age was 71 years (interquartile range (IQR) 17), 160 patients (61.5%) were male, the median baseline National Institute of Health Stroke Scale (NIHSS) score was 8 (IQR 13). Of these, 159 (61.2%) patients had a hypertensive sICH and 156 patients (60%) had LVH. In univariable (113/159 (71.1%) vs. 43/101 (42.6%); odds ratio (OR) 3.31; 95% confidence interval (CI_95%) 1.97-5.62); and multivariable (adjusted OR 2.95; CI_95% 1.29-6.74) analysis, hypertensive sICH was associated with LVH.

CONCLUSIONS

In patients with sICH, LVH is associated with hypertensive bleeding etiology. Performing TTE is meaningful for diagnosis of comorbidities and clarification of bleeding etiology in these patients. Future studies should include long-term outcome parameters and assess left ventricular mass as main indicator for LVH.

Usefulness of Transesophageal Echocardiography for Predicting Covert Paroxysmal Atrial Fibrillation in Patients with Embolic Stroke of Undetermined Source

BACKGROUND

Covert paroxysmal atrial fibrillation (CPAF) is a major cause of embolic stroke of undetermined source (ESUS). However, detecting PAF during hospitalization in these patients is difficult.

OBJECTIVES

This study aimed to determine whether findings of transesophageal echocardiography (TEE) during hospitalization are associated with later detection of PAF in patients with ESUS.

METHOD

We retrospectively studied 348 patients with ESUS who were admitted to our hospital within 1 week of onset. These patients met the criteria of ESUS, underwent TEE during hospitalization, and were followed up for at least 1 year.

RESULTS

We found PAF in 35 (10.0%) patients. In patients with PAF, spontaneous echo contrast (SEC) and low left atrial appendage flow (LAAF) by TEE and enlargement of the left atrial dimension (LAD) by transthoracic echocardiography were identified more frequently compared with those who did not have PAF. In multivariate analysis, SEC and an LAD ≥42 mm were independently associated with later detection of PAF (p < 0.05). An association of LAAF <46.9 cm/s and PAF was marginal (p = 0.09). The specificity of the combined finding of SEC and/or LAAF with that of LAD increased up to 90%, while that of LAD alone was 70%.

CONCLUSIONS

The findings of TEE during hospitalization may be useful for identifying patients at increased risk of CPAF in patients with ESUS.

Embolic strokes of undetermined source: theoretical construct or useful clinical tool?

In 2014, the definition of embolic strokes of undetermined source (ESUS) emerged as a new clinical construct to characterize cryptogenic stroke (CS) patients with complete vascular workup to determine nonlacunar, nonatherosclerotic strokes of presumable embolic origin. NAVIGATE ESUS, the first phase III randomized-controlled, clinical trial (RCT) comparing rivaroxaban (15 mg daily) with aspirin (100 mg daily), was prematurely terminated for lack of efficacy after enrollment of 7213 patients. Except for the lack of efficacy in the primary outcome, rivaroxaban was associated with increased risk of major bleeding and hemorrhagic stroke compared with aspirin. RE-SPECT ESUS was the second phase III RCT that compared the efficacy and safety of dabigatran (110 or 150 mg, twice daily) to aspirin (100 mg daily). The results of this trial have been recently presented and showed similar efficacy and safety outcomes between dabigatran and aspirin. Indirect analyses of these trials suggest similar efficacy on the risk of ischemic stroke (IS) prevention, but higher intracranial hemorrhage risk in ESUS patients receiving rivaroxaban compared to those receiving dabigatran (indirect HR = 6.63, 95% CI: 1.38-31.76). ESUS constitute a heterogeneous group of patients with embolic cerebral infarction. Occult AF represents the underlying mechanism of cerebral ischemia in the minority of ESUS patients. Other embolic mechanisms (paradoxical embolism via patent foramen ovale, aortic plaque, nonstenosing unstable carotid plaque, etc.) may represent alternative mechanisms of cerebral embolism in ESUS, and may mandate different management than oral anticoagulation. The potential clinical utility of ESUS may be challenged since the concept failed to identify patients who would benefit from anticoagulation therapy. Compared with the former diagnosis of CS, ESUS patients required thorough investigations; more comprehensive diagnostic work-up than is requested in current ESUS diagnostic criteria may assist clinicians in uncovering the source of brain embolism in CS patients and individualize treatment approaches.

The value of transesophageal echocardiography for embolic strokes of undetermined source

OBJECTIVE

Our aim was to evaluate the diagnostic yield of transesophageal echocardiography (TEE) in consecutive patients with ischemic stroke (IS) fulfilling the diagnostic criteria of embolic strokes of undetermined source (ESUS).

METHODS

We prospectively evaluated consecutive patients with acute IS satisfying ESUS criteria who underwent in-hospital TEE examination in 3 tertiary care stroke centers during a 12-month period. We also performed a systematic review and meta-analysis estimating the cumulative effect of TEE findings on therapeutic management for secondary stroke prevention among different IS subgroups.

RESULTS

We identified 61 patients with ESUS who underwent investigation with TEE (mean age 44 ± 12 years, 49% men, median NIH Stroke Scale score = 5 points [interquartile range: 3-8]). TEE revealed additional findings in 52% (95% confidence interval [CI]: 40%-65%) of the study population. TEE findings changed management (initiation of anticoagulation therapy, administration of IV antibiotic therapy, and patent foramen ovale closure) in 10 (16% [95% CI: 9%-28%]) patients. The pooled rate of reported anticoagulation therapy attributed to abnormal TEE findings among 3,562 acute IS patients included in the meta-analysis (12 studies) was 8.7% (95% CI: 7.3%-10.4%). In subgroup analysis, the rates of initiation of anticoagulation therapy on the basis of TEE investigation did not differ (p = 0.315) among patients with cryptogenic stroke (6.9% [95% CI: 4.9%-9.6%]), ESUS (8.1% [95% CI: 3.4%-18.1%]), and IS (9.4% [95% CI: 7.5%-11.8%]).

CONCLUSIONS

Abnormal TEE findings may decisively affect the selection of appropriate therapeutic strategy in approximately 1 of 7 patients with ESUS.