Diagnosis of Patent Foramen Ovale: The Combination of Contrast Transcranial Doppler, Contrast Transthoracic Echocardiography, and Contrast Transesophageal Echocardiography

Diagnostic value of contrast-enhanced ultrasonography for patent foramen ovale detection

Background

Patent foramen ovale (PFO) has been associated with migraine, cryptogenic stroke (CS), and hypoxemia. However, which examination method is most reliable remains controversial. This study sought to investigate the diagnostic value of contrast-enhanced ultrasonography (cU), including contrast-enhanced transcranial Doppler (cTCD), contrast transthoracic echocardiography (cTTE), and contrast transesophageal echocardiography (cTEE), for PFO; and to determine the best diagnostic strategy.

Methods

This retrospective observational study included a total of 147 consecutive patients suspected PFO at The First Hospital of Shanxi Medical University between October 2019 and January 2022. The patients also underwent cTCD, cTTE, and cTEE examinations. The standard for the diagnosis of PFO was confirmation of the presence of PFO by color Doppler flow signals or contrast microbubbles (MBs) passing through the foramen ovale.

Results

A total of 123 patients were diagnosed with PFO and 24 patients without PFO during the study period. The detectable rates of cTCD, cTTE, and cTEE were 120 (97.56%), 110 (89.43%), and 121 (98.37%), respectively. The sensitivity between cTCD and cTEE for PFO were comparable [97.56%, 95% confidence interval (CI): 92.5% to 99.4% vs. 98.37%, 95% CI: 93.7% to 99.7%; P>0.99], and the sensitivity of both were higher than that of cTTE (89.43%, 95% CI: 82.3% to 94.0%; P=0.02 and P=0.001, respectively). In addition, the specificity of cTEE for PFO was significantly higher than that of cTCD (100%, 95% CI: 82.3% to 100.0% vs. 75.00%, 95% CI: 53.0% to 89.4%; P<0.001) and cTTE (100%, 95% CI: 82.3% to 100.0% vs. 75.00%, 95% CI: 53.0% to 89.4%; P<0.001). Further, the semi-quantitative classification ability of cTCD for PFO with right-to-left shunt (RLS) was significantly higher than that of cTTE and cTEE (P=0.02 and P<0.001, respectively), and that of cTTE was significantly higher than that of cTEE (P=0.01). The Spearman analysis showed that the degree of RLS was positively correlated with the inner diameter of the PFO (r=0.695, P<0.001).

Conclusions

The combination of cTCD and cTEE may provide a favorable strategy for the diagnosis of PFO.

Contrast-enhanced transcranial doppler versus contrast transthoracic echocardiography for right-to-left shunt diagnosis

RLS can be diagnosed using US, CT angiography, and right heart catheterization. However, most reliable diagnostic modality remains undetermined. c-TCD was more sensitive than c-TTE in the diagnosis of RLS. This was true especially for the detection of provoked shunts or mild shunts. c-TCD can be used as the preferred screening method for RLS.

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.

Transesophageal echocardiography-guided percutaneous closure of the patent foramen ovale only uses the sheath

Background

Percutaneous closure of the patent foramen ovale (PFO) is primarily guided by fluoroscopy in the catheter room, during which procedure both the guidewire and sheath need to pass through the PFO. We performed PFO closure using a transesophageal echocardiography (TEE)-guided approach and only the sheath was passed through the PFO during the procedure. This study aimed to evaluate the feasibility and safety of PFO closure using this technique.

Methods

A retrospective observational study was performed. A total of 117 consecutive adult patients underwent percutaneous PFO closure without fluoroscopy, under the sole guidance of TEE in our hospital between December 2018 and December 2021. The data of each patient consisted of preoperative, operative, and postoperative variables collected. The primary outcome is that the occluder was successfully released. The secondary outcomes included perioperative and follow-up transthoracic echocardiography (TTE), Headache impact test-6 (HIT-6) score and clinical symptoms.

Results

Transvenous PFO closure under TEE guidance was successful in all cases. The sample consisted of 93 females and 24 males with an average age of 42.3±7.8 years. There were 28 patients with preoperative cerebral infarction [Risk of Paradoxical Embolism (RoPE) score >6 points] and 89 patients with migraine. All patients underwent a preoperative TEE to confirm the presence of PFO, and contrast-enhanced transcranial Doppler (c-TCD) acoustic contrast suggested grades 3 to 4. The average time of surgery for patients (puncture to removal of the sheath) was 32 minutes. Three cases of vagus nerve reflex manifestations during surgery and two cases of transient ventricular arrhythmia all improved after symptomatic treatment. There were no instances of metal allergy, hemolysis, or other acute vascular procedural complications. For all 89 patients with migraine, significant relief or resolution was achieved during the first six-month follow-up (P<0.001).

Conclusions

As a monotherapy, percutaneous closure of PFO guided by TEE where only the sheath passes through the PFO during the operation is an effective procedure with a high success rate and a low complication rate.

Case report: Anxiety and depression as initial symptoms in a patient with acute hypoxia and patent foramen ovale

The prevalence of patent foramen ovale (PFO) is 15-35% among adults. The role of right-to-left shunting through the PFO, anxiety, depression, and hypoxemia in the systemic circulation remains poorly understood. Herein, we present the case of a 52-year-old woman with no heart or lung disease, who was admitted due to anxiety for 5 months and had symptom exacerbation with dizziness for 4 days and presented with cyanosis. She was noted to have acute hypoxemia, with an oxygen saturation of 94.48% on room air, and arterial blood gas showed an oxygen tension of 65.64 mmHg. Agitated saline contrast echocardiography showed right-to-left shunting due to PFO. Arteriovenous fistula, pneumonia, pulmonary embolism, pulmonary hypertension, congestion peripheral cyanosis, ischemic peripheral cyanosis, and methemoglobin were excluded. Additionally, the patient improved by taking Paroxetine, Oxazepam, and Olanzapine. Her oxygen tension returned to 90.42 mmHg, and her symptoms resolved. In the case of severe anxiety and depression, right-to-left shunting through the PFO may cause acute systemic hypoxemia via a flow-driven mechanism, occasionally manifesting as cyanosis. When anxiety improved, hypoxia also improved. Thus, the treatment of anxiety and depression seems effective in improving hypoxemia. Notably, this is a rare report, and we hope to draw the attention of psychosomatic specialists, psychiatrists, and clinicians to seek the relationship between anxiety appearing as acute stress and PFO. This may be a new therapeutic method for treating severe anxiety disorder.

Synchronous multimode ultrasound for assessing right-to-left shunt: a prospective clinical study

Background

Right-to-left shunt (RLS) is associated with several conditions and causes morbidity. In this study, we aimed to evaluate the effectiveness of synchronous multimode ultrasonography in detecting RLS.

Methods

We prospectively enrolled 423 patients with high clinical suspicion of RLS and divided them into the contrast transcranial Doppler (cTCD) group and synchronous multimode ultrasound group, in which both cTCD and contrast transthoracic echocardiography (cTTE) were performed during the same process of contrast-enhanced ultrasound imaging. The simultaneous test results were compared with those of cTCD alone.

Results

The positive rates of grade II (22.0%:10.0%) and III (12.7%:10.8%) shunts and the total positive rate (82.1748%) in the synchronous multimode ultrasound group were higher than those in the cTCD alone group. Among patients with RLS grade I in the synchronous multimode ultrasound group, 23 had RLS grade I in cTCD but grade 0 in synchronous cTTE, whereas four had grade I in cTCD but grade 0 in synchronous cTTE. Among patients with RLS grade II in the synchronous multimode ultrasound group, 28 had RLS grade I in cTCD but grade II in synchronous cTTE. Among patients with RLS grade III in the synchronous multimode ultrasound group, four had RLS grade I in cTCD but grade III in synchronous cTTE. Synchronous multimode ultrasound had a sensitivity of 87.5% and specificity of 60.6% in the patent foramen ovale (PFO) diagnosis. Binary logistic regression analyses showed that age (odds ratio [OR] = 1.041) and risk of paradoxical embolism score ≥ 7 (OR = 7.798) were risk factors for stroke recurrence, whereas antiplatelets (OR = 0.590) and PFO closure with antiplatelets (OR = 0.109) were protective factors.

Conclusion

Synchronous multimodal ultrasound significantly improves the detection rate and test efficiency, quantifies RLS more accurately, and reduces testing risks and medical costs. We conclude that synchronous multimodal ultrasound has significant potential for clinical applications.

Change in patent foramen ovale height is associated with cryptogenic stroke and the construction of a morphology-based scoring system

Introduction

Current guidelines recommended patent foramen ovale (PFO) occlusion as the preferred treatment for PFO-related cryptogenic stroke (CS); however, finding the causative foramen ovale remains challenging. This study aimed to identify predictors and establish a scoring system by assessing PFO morphology and stroke-related factors.

Methods

Based on a prospective multicenter registered clinical trial, we compared data mainly derived from transesophageal echocardiography (TEE) and clinical history in patients with PFO-related CS and those without CS (non-CS) with incidental PFO. Subsequently, we explored independent predictors using logistic analysis, established a scoring system based on the results, and finally evaluated the scoring system using receiver operating characteristic (ROC) analysis and internal validation.

Results

75 patients with PFO-related CS and 147 non-CS patients were enrolled. Multivariate logistic analysis showed that the change in PFO height, large PFO, atrial septal aneurysm (ASA), and sustained right-to-left shunt (RLS) had independent relationships with CS. Based on the odds ratio value of each independent factor, a scoring system was built: change in PFO height ≥ 1.85 mm (3 points), large PFO (2 points), ASA (5 points), sustained RLS (2 points). 0–2 points correspond to low-risk PFO, 3–5 points medium-risk PFO, and 7–12 points high-risk PFO. ROC analysis showed an area under the curve of 0.80 to predict CS. The proportion of patients with CS is increasing based on these points.

Conclusions

Our study screened out the change in PFO height as an independent predictor of CS. A simple and convenient scoring system can provide constructive guidance for identifying whether the PFO is causal and consequently selecting patients more likely to benefit from closure.

The Relationship Between Patent Foramen Ovale and Unexplained Dizziness: A Prospective Analysis in China

INTRODUCTION

Patent foramen ovale (PFO) is potentially associated with abnormal embolisms, and it results in mixing of arteriovenous blood when its right-to-left shunt (RLS) emerges. Present studies have found that PFO is a risk factor that can lead to many diseases. However, few studies have examined the relationship between PFO and dizziness.

METHODS

This study was a large single-center, prospective, controlled study. From March 2019 to March 2021, we recruited patients with dizziness were divided into two groups: "explained" and "unexplained". All patients were submitted to contrast-enhanced transcranial Doppler ultrasound and screened for PFO. Transesophageal heart ultrasound or right heart catheterization was used to confirm PFO. Additionally, multiple factors were collected and statistical analysis was performed between the two groups.

RESULTS

Among the 244 patients included, 123 were in the "explained" group and 121 were in the "unexplained" group. The prevalence of PFO in the "explained" group was 34 (27.4%) compared to 79 (64.7%) in the "unexplained" group. In the "explained" group, 7 were RLS level IV, 6 were level III, 7 were level II, and 14 were level I. For the "unexplained" group, the numbers of patients with levels IV, III, II and I were 27, 26, 12 and 14, respectively. Univariate analysis revealed that PFO (χ²= 34.77, P < 0.001) and age (t = -3.49, P < 0.001) seemed to be potential risk factor candidates for "unexplained" dizziness. In multiple regression analysis, age (OR = 0.97; 95% CI 0.95-0.99) and the prevalence of PFO (OR = 4.37; 95% CI 2.50-7.63) were statistically significant. Massively shunted PFO showed more pronounced risk factors (OR = 8.76; 95% CI 4.04-19.03).

CONCLUSION

There was a high prevalence of PFO and a greater RLS level in unexplained dizziness. PFO and age were independent risk factors for unexplained dizziness. When treating with unexplained dizziness, especially among young people, we must pay attention to the presence of PFO.

Platypnea Orthodeoxia Due to a Patent Foramen Ovale and Intrapulmonary Shunting After Severe COVID-19 Pneumonia

Patient: Male, 85-year-old

Final Diagnosis: Platypnea orthodeoxia

Symptoms: Dyspnea • orthostatic intolerance

Medication: —

Clinical Procedure: —

Specialty: Infectious Diseases

Applicability of Transthoracic Contrast Echocardiography for the Diagnosis and Treatment of Idiopathic Pulmonary Arteriovenous Malformations

Objective: To explore the preferred test to screen for pulmonary arteriovenous malformations (PAVMs) and to predict the probability of interventional embolization. Methods: We performed a retrospective observational study evaluating patients with idiopathic PAVMs from 2009 to 2019. After clinical evaluation, a total of 105 patients were studied, including 71 patients with positive digital subtraction pulmonary angiography (DSPA) findings and 34 with negative DSPA findings. The following patient data were assessed: blood test, chest radiograph, transthoracic contrast echocardiography (TTCE), and DSPA findings. Results: The majority of patients with idiopathic PAVMs were female (66.2% with positive DSPA findings). We found a good κ-coefficient of 0.77 with strong consistency for inter observer agreement concerning the pulmonary right-to-left shunt (RLS) grade on TTCE, which was superior to conventional chest radiographs. The positive predictive value (PPV) of the radiographic features for PAVMs on DSPA was 0.83 (95% CI 0.64-1.0) and 0.44 for the possibility of embolization (95% CI 0.19-0.70). The PPV of the shunt grade of PAVMs on DSPA was 0.14 (95% CI 0.01-0.29) for grade 1, 0.74 (95% CI 0.60-0.88) for grade 2, and 0.97 (95% CI 0.92-1.0) for grade 3. The PPVs of pulmonary shunt grades 2 and 3 on TTCE for the possibility of embolization for PAVMs were 0.21 (95% CI, 0.05-0.36) and 0.87 (95% CI, 0.79-0.99), respectively. Conclusion: TTCE is the preferred screening test for PAVMs. The pulmonary RLS grade on TTCE not only identifies the likelihood of PAVMs but also predicts the probability for embolization.