Pneumothorax during manned chamber operations: A summary of reported cases.

In-chamber pneumothorax has complicated medically remote professional diving operations, submarine escape training, management of decompression illness, and hospital-based provision of hyperbaric oxygen therapy. Attempts to avoid thoracotomy by combination of high oxygen partial pressure breathing (the concept of inherent unsaturation) and greatly slowed rates of chamber decompression proved successful on several occasions. When this delicate balance designed to prevent the intrapleural gas volume from expanding faster than it contracts proved futile, chest drains were inserted. The presence of pneumothorax was misdiagnosed or missed altogether with disturbing frequency, resulting in wide-ranging clinical consequences. One patient succumbed before the chamber had been fully decompressed. Another was able to ambulate unaided from the chamber before being diagnosed and managed conventionally. In between these two extremes, patients experienced varying degrees of clinical compromise, from respiratory distress to cardiopulmonary arrest, with successful resuscitation. Pneumothorax associated with manned chamber operations is commonly considered to develop while the patient is under pressure and manifests during ascent. However, published reports suggest that many were pre-existing prior to chamber entry. Risk factors included pulmonary barotrauma-induced cerebral arterial gas embolism, cardiopulmonary resuscitation, and medical or surgical procedures usually involving the lung. This latter category is of heightened importance to hyperbaric operations as an iatrogenically induced pneumothorax may take as long as 24 hours to be detected, perhaps long after a patient has been cleared for chamber exposure.

Vasculitic rash and cerebral emboli in an adolescent with left atrial myxoma.

A previously healthy woman in late adolescence presented to the emergency department with stroke-like symptoms following a two-month history of bilateral foot pain and oedema, accompanied by a macular rash and progressive lower extremity weakness. On further investigation, she was found to have multiple cerebral emboli and a left atrial myxoma fixed to the interatrial septum. The patient subsequently underwent urgent surgical excision of the myxoma. On follow-up, her cutaneous and neurological symptoms were significantly improved. This case suggests that, in the presence of a vasculitic rash without evident or obvious cause, cardiac myxoma should be included in the differential diagnosis.

Left atrial strain, embolic stroke of undetermined source, and atrial fibrillation detection.

BACKGROUND: Atrial cardiopathy is a proposed mechanism of embolic stroke of undetermined source (ESUS). Left atrial (LA) strain may identify early atrial cardiopathy prior to structural changes. We aim to study the associations between LA strain, ESUS, and atrial fibrillation (AF) detection in ESUS. METHODS: The study population included patients with ESUS and noncardioembolic (NCE) stroke presenting to the Rhode Island Hospital Stroke Center between January 2016 and June 2017 who underwent transthoracic echocardiography. Speckle tracking echocardiography (STE) was used to measure the three phases of LA strain (reservoir, conduit, and contractile). Binary logistic regression analysis was performed to determine the associations between LA strain and stroke subtype (ESUS vs. NCE) as well as follow-up detection of AF in ESUS patients. RESULTS: We identified 656 patients, 307 with ESUS and 349 with NCE. In binary logistic regression, the lowest tertiles of LA reservoir (adjusted OR 1.944, 95% CI 1.266-2.986, p = .002), contractile (aOR 1.568, 95% CI 1.035-2.374, p = .034), and conduit strain (aOR 2.288, 95% CI 1.448-3.613, p = .001) were more likely to be significantly associated with ESUS compared to NCE stroke. Among all ESUS patients, the lowest tertiles of LA reservoir strain (OR 2.534, 95% CI 1.029-6.236, p = .043), contractile strain (OR 2.828, 95% CI 1.158-6.903, p = .022), and conduit strain (OR 2.614, 95% CI 1.003-6.815, p = .049) were significantly associated with subsequent detection of AF. CONCLUSION: Reduced LA strain is associated with ESUS occurrence and AF detection in ESUS patients. Therefore, quantification of LA strain in ESUS patients may improve risk stratification and guide secondary prevention strategies.

Thin aortic arch plaque is associated with the development of atrial fibrillation for embolic stroke of undetermined source in patients with an insertable cardiac monitor.

BACKGROUND AND OBJECTIVE: This study's objective is to investigate whether mild aortic arch plaque is associated with the development of atrial fibrillation (AF) in stroke patients with embolic stroke of undetermined source (ESUS) during the first year following the implantation of an insertable cardiac monitor (ICM). METHODS: The participants in this cross-sectional observational study were consecutive patients with ESUS, even after transesophageal echocardiography. We assessed the relationship between the thickness of the participants' aortic arch plaque and AF detected after ICM implantation. RESULTS: Of the 50 consecutive patients with ESUS enrolled in this study, 12 (24%) developed AF. We observed that thicker aortic arch plaque was associated with undetected AF (2.3 mm vs. 1.2 mm, p < 0.001). Aortic arch plaque thickness was independent associated with undetected AF (OR 54.00, 95% CI 2.706-1077.544, p = 0.009). When the cut-off value for aortic arch plaque thickness was 1.8 mm, the sensitivity and specificity were 71.1% and 91.7%, respectively (95% CI = 0.75-0.98, p < 0.001). Also, patients having both aortic arch plaque with a thickness < 1.8 mm and a CHADS2 score ≥ 4 were more likely to have detectable AF than no AF (88% vs. 12%, p < 0.001). CONCLUSION: A thinner aortic arch plaque was associated with the development of AF. Patients with mild aortic plaques below 4 mm but ≥1.8 mm in thickness and without other high-risk features are less likely to have paroxysmal AF on ICM, and these plaques may be a possible source of embolism for their strokes.

High Prevalence of New Clinically Significant Findings in Patients With Embolic Stroke of Unknown Source Evaluated by Cardiac Magnetic Resonance Imaging.

BACKGROUND: Embolic stroke of unknown source (ESUS) accounts for 1 in 6 ischemic strokes. Current guidelines do not recommend routine cardiac magnetic resonance (CMR) imaging in ESUS, and beyond the identification of cardioembolic sources, there are no data assessing new clinical findings from CMR in ESUS. This study aimed to assess the prevalence of new cardiac and noncardiac findings and to determine their impact on clinical care in patients with ESUS. METHODS AND RESULTS: In this prospective, multicenter, observational study, CMR imaging was performed within 3 months of ESUS. All scans were reported according to standard clinical practice. A new clinical finding was defined as one not previously identified through prior clinical evaluation. A clinically significant finding was defined as one resulting in further investigation, follow-up, or treatment. A change in patient care was defined as initiation of medical, interventional, surgical, or palliative care. From 102 patients recruited, 96 underwent CMR imaging. One or more new clinical findings were observed in 59 patients (61%). New findings were clinically significant in 48 (81%) of these patients. Of 40 patients with a new clinically significant cardiac finding, 21 (53%) experienced a change in care (medical therapy, n=15; interventional/surgical procedure, n=6). In 12 patients with a new clinically significant extracardiac finding, 6 (50%) experienced a change in care (medical therapy, n=4; palliative care, n=2). CONCLUSIONS: CMR imaging identifies new clinically significant cardiac and noncardiac findings in half of patients with recent ESUS. Advanced cardiovascular screening should be considered in patients with ESUS. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04555538.

Role of Cerebral Embolic Protection Devices in Patients Undergoing Transcatheter Aortic Valve Replacement: An Updated Meta-Analysis.

BACKGROUND: Cerebral embolic protection devices (CEPD) capture embolic material in an attempt to reduce ischemic brain injury during transcatheter aortic valve replacement. Prior reports have indicated mixed results regarding the benefits of these devices. With new data emerging, we performed an updated meta-analysis examining the effect of CEPD during transcatheter aortic valve replacement on various clinical, neurological, and safety parameters. METHODS AND RESULTS: A comprehensive review of electronic databases was performed comparing CEPD and no-CEPD in transcatheter aortic valve replacement. Primary clinical outcome was all-cause stroke. Secondary clinical outcomes were disabling stroke and all-cause mortality. Neurological outcomes included worsening of the National Institutes of Health Stroke Scale score, Montreal Cognitive Assessment score from baseline at discharge, presence of new ischemic lesions, and total lesion volume on neuroimaging. Safety outcomes included major or minor vascular complications and stage 2 or 3 acute kidney injury. Seven randomized controlled trials with 4016 patients met the inclusion criteria. There was no statistically significant difference in the primary clinical outcome of all-cause stroke; secondary clinical outcomes of disabling stroke, all-cause mortality, neurological outcomes of National Institutes of Health Stroke Scale score worsening, Montreal Cognitive Assessment worsening, presence of new ischemic lesions, or total lesion volume on diffusion-weighted magnetic resonance imaging between CEPD versus control groups. There was no statistically significant difference in major or minor vascular complications or stage 2 or 3 acute kidney injury between the groups. CONCLUSIONS: The use of CEPD in transcatheter aortic valve replacement was not associated with a statistically significant reduction in the risk of clinical, neurological, and safety outcomes.

Large Tissue Debris Causing Cerebral Embolism After Transcatheter Aortic Valve Replacement.

Cerebral vascular embolism is one of the complications of transcatheter aortic valve replacement (TAVR). Thrombolytic therapy is not expected to be effective when embolic material consists of a large tissue fragment. Instead, mechanical aspiration may be more effective therapy for acute cerebral infarction after TAVR. Here, we describe the case of an 87-year-old woman with aortic valve stenosis and heart failure who underwent TAVR using a self-expandable valve. Acute cerebral infarction with left middle cerebral artery occlusion caused by a large tissue fragment developed after the procedure.

Cerebral Embolism and MINOCA Secondary to Left Atrial Myxoma after Occlusion of Atrial Septal Defect by Amplatzer Occluder: A Case Report.

Primary heart tumors are rare, with atrial myxomas being the most common type. Atrial myxomas can lead to embolisms, heart obstruction, and systemic symptoms. Herein, we report a case of 72-year-old woman who presented with a left atrial myxoma at the atrial septal defect occluder, a new acute cerebral infarction, and MINOCA (myocardial infarction with no obstructive coronary atherosclerosis). Left atrial myxoma is a common primary cardiac tumor; however, left atrial myxomas arising after percutaneous atrial septal defect occlusion are rare. Additionally, the patient presented with a new case of multiple systemic emboli. The patient underwent surgical resection of a left atrial myxoma, occluder, and left atrium, and atrial septal repair, and was discharged with good recovery for outpatient follow-up. The possibility of a cardiac tumor, especially an atrial myxoma, which can lead to a series of complications, should be considered at the closure site after percutaneous atrial septal closure. Therefore, active surgical treatment and long-term follow-up are warranted in such cases.

Effectiveness of statins on outcomes of patients with Embolic Stroke of Undetermined Source (ESUS).

BACKGROUND: Statins are highly recommended as a secondary prevention strategy after a stroke. Embolic Stroke of Undetermined Source (ESUS) accounts for up to one fifth of cases of ischemic stroke. There is a lack of studies investigating the effectiveness of statins in this subgroup of patients. METHODS: We designed a longitudinal cohort study involving patients properly diagnosed with ESUS. Data about statin therapy included information about the time of initiation of the treatment, pre-stroke statin use, statin withdrawal, and the type and dosage of the statin prescribed. Patients were followed for 48 months after the index stroke. The primary endpoints included stroke recurrence, major cardiovascular events, and death from all causes. The secondary endpoint was the functional outcome, assessed in a standardized and systematic way using the modified Rankin Scale (mRS). RESULTS: Patients who were not taking any statin after ESUS have significantly increased odds of stroke recurrence (OR = 3.29, 95% CI 1.27 - 8.55) or presenting the composite outcome of stroke recurrence, major cardiovascular events, and death (OR = 3.70, 95% CI 1.44 - 9.50) in the multivariate analysis. No statin therapy was directly associated with the functional outcome as well (OR = 3.32, 95% CI = 1.58 - 6.96). The early initiation of the statin therapy was estimated to reduce the risk of a second stroke and the composite outcome by 89% and 87%. CONCLUSIONS: Our pioneering study provides evidence that patients with ESUS may benefit from statin therapy, especially if prescribed early and at higher dosages.

Magnetic resonance imaging for diagnostic workup of embolic stroke of undetermined source: A systematic review.

BACKGROUND: Embolic stroke of undetermined source (ESUS) refers to ischemic stroke where the underlying cause of thromboembolism cannot be found despite the recommended diagnostic workup. Unidentified source of emboli hinders clinical decision-making and patient management with detrimental consequences on long-term prognosis. The rapid development and versatility of magnetic resonance imaging (MRI) make it an appealing addition to the diagnostic routine of patients with ESUS for the assessment of potential vascular and cardiac embolic sources. AIMS: To review the use of MRI in the identification of cardiac and vascular embolic sources in ESUS and to assess the reclassification value of MRI examinations added to the conventional workup of ESUS. SUMMARY OF REVIEW: We reviewed the use of cardiac and vascular MRI for the identification of a variety of embolic sources associated with ESUS, including atrial cardiomyopathy, left ventricular pathologies, and supracervical atherosclerosis in carotid and intracranial arteries and in distal thoracic aorta. The additional reclassification after MRI examinations added to the workup of patients with ESUS ranged from 6.1% to 82.3% and varied depending on the combination of imaging modalities. CONCLUSION: MRI techniques allow us to identify additional cardiac and vascular embolic sources and may further decrease the prevalence of patients with the diagnosis of ESUS.

Midterm follow-up after computed tomography angiography planned left atrial appendage closure.

BACKGROUND: While studies have shown the advantages of computed tomography angiography (CTA) over transesophageal echocardiography (TEE) in left atrial appendage closure (LAAC) preprocedural planning for WATCHMAN™ legacy and FLX devices, there has been no reported long-term data for this approach. OBJECTIVES: We sought to evaluate long-term outcomes using CTA-based preprocedural planning for LAAC using the WATCHMAN™ device. METHODS: A prospective analysis of 231 consecutive patients who underwent LAAC in a single, large academic hospital in the United States was conducted over a 5-year period. CTA-guided preprocedural planning was performed in all. Procedural success, adverse events, length of procedure, number of devices used, and length of stay were evaluated. Rates of death, cerebral embolism, systemic embolism, and major and minor bleeding were recorded. Adjusted predicted stroke and major bleeding rates were derived from CHA2DS2-Vasc and HAS-BLED scores, respectively. RESULTS: From January 26, 2017, to November 23, 2021, 231 patients underwent LAAC with CTA preprocedural planning by two operating physicians. The mean age of patients was 76.5 ± 8.4. 59.7% of patients were male. Mean CHA2DS2VASc and HAS-BLED scores were 4.5 ± 1.4 and 3.9 ± 0.9, respectively. All procedures were performed with intracardiac echo (100%). The procedural success rate was 99.1%. The CTA sizing strategy accurately predicted the implant size in 93.5% of patients. Mean number of devices used was 1.10 ± 0.3. Peri-procedural complication rate was 2.2%. 6 patients were lost to follow-up. Mean follow-up was 608.94 days with a total of 377.04 patient years. Median follow-up period of 368 days (interquartile range: 209-1067 days). There were 51 deaths from all causes (13.52 per 100 patient-years), 10 cases of cerebral embolism (2.65 per 100 patient-years), 2 cases of systemic embolism (0.53 per 100 patient-years), 17 cases of major bleeding (4.50 per 100 patient-years), and 31 cases of minor bleeding (8.2 per 100 patient-years). All-cause mortality at 1, 2, and 3 years was 12.7%, 20.9%, and 29.2%, respectively. CV event rates at 1, 2, and 3 years were 2.1%, 6.6%, and 10.5%, respectively. CONCLUSIONS: CTA-based preprocedural planning is accurate in predicting device size for LAAC and associated with excellent clinical outcomes at 5 years.

Detection of microemboli in patients with acute ischaemic stroke and atrial fibrillation suggests poor functional outcome.

INTRODUCTION: We investigated the burden of microembolic signals (MES) in patients with acute ischaemic stroke (AIS) and atrial fibrillation (AF), assessing their impact on functional outcomes. PATIENTS AND METHODS: This multicentre international prospective cohort study involved patients with AIS and either a known or newly diagnosed anticoagulant-naïve AF. All centres utilised the same transcranial Doppler machine for 1-h monitoring with bilateral 2 MHz probes within 24 h of symptom onset. Recordings underwent MES analysis by a blinded central reader. The primary objectives were to ascertain the MES proportion and its association with functional outcomes assessed by the modified Rankin scale (mRS) score at 90 days. RESULTS: Between September 2019 and May 2021, we enrolled 61 patients, with a median age of 78 years (interquartile range 73-83) and a median stroke severity score of 11 (interquartile range 4-18). MES were observed in 14 patients (23%), predominantly unilateral (12/14, 86%), with a median rate of 6 counts/hour (interquartile range 4-18). MES occurrence was higher post-thrombectomy and among those with elevated brain natriuretic peptide levels (p < 0.05). A worse mRS score of 3-6 was more frequent in patients with MES, occurring in 11/14 (79%), compared to those without MES, 20/47 (43%), with an adjusted odds ratio of 5.04 (95% CI, 1.15-39.4), p = 0.04. CONCLUSIONS: Nearly a quarter of patients with AIS and AF exhibited silent microembolization after the index event. Detecting MES within 24 h post-stroke (using transcranial Doppler) could signify a marker of poor functional outcomes. Subsequent trials will assess if very early antithrombotic treatment might enhance outcomes in this highly selective group of cardioembolic stroke patients. (Clinicaltrials.gov ID: NCT06018090).

Sex-Specific Risk Factors of Nonstenotic Carotid Plaque in Embolic Stroke of Unknown Source: A Case-Control Study.

BACKGROUND: Many ischemic strokes are diagnosed as embolic strokes of undetermined source (ESUS). Recent evidence suggests that nonstenotic carotid plaque (nsCP) may be a substantial contributor to the risk for ESUS. We aimed to investigate the risk factor profile associated with nsCP in ESUS and defined stroke etiologies. METHODS: In this retrospective case-control study, we investigated consecutive patients with acute ischemic stroke due to ESUS, small-vessel disease, or cardioembolism proven by magnetic resonance imaging. The association of vascular risk factors age, arterial hypertension, diabetes, dyslipoproteinemia, body mass index, alcohol consumption, tobacco use, kidney failure, and history of stroke with the presence of nsCP was investigated using binary logistic regression analysis and further stratified by stroke etiology and sex. RESULTS: In total, 609 patients (median age, 76 years; 46% women) who were treated from 2018 to 2020 were considered. In patients with ESUS, sex played a more important role for the prevalence of nsCP than in defined etiologies. Female patients with ESUS had lower odds of exhibiting nsCP compared with male patients with ESUS (adjusted odds ratio, 0.36 [95% CI, 0.15-0.86]). In male patients with ESUS, we observed that age (adjusted odds ratio per 10-year increase, 2.55 [95% CI, 1.26-5.17]) and hypertension (adjusted odds ratio, 2.49 [95% CI, 0.56-11.1]) were the main risk factors for nsCP, whereas in female patients with ESUS also tobacco use was particularly relevant (adjusted odds ratio, 3.71 [95% CI, 0.61-22.5]). These results were in line with a sensitivity analysis in nsCP located ipsilateral to the infarct. CONCLUSIONS: Sex differences play an important role in nsCP prevalence in patients with ESUS. These findings may have important implications for the management in targeted secondary prevention following ESUS.

[Cerebral arterial air embolism: the effect of hyperbaric oxygen therapy]. / Cerebrale arteriële luchtembolie.

BACKGROUND: Iatrogenic gas embolism is the presence of gas in vascular structures. Feared are those in coronary or cerebral arteries. These can result in cerebral or myocardial infarction. CASE DESCRIPTION: A 79-year-old female underwent CT-guided biopsy of the lung. Minutes later she developed neurological symptoms. After administration of oxygen her symptoms initially improved, but later worsened. Based on her symptoms air embolism was suspected. She recovered fully after treatment with hyperbaric oxygen. CONCLUSION: Air embolism is a potentially life-threatening complication of surgical, radiological or vascular interventions. Early recognition can lead to prompt treatment and better prognosis. If air embolism is suspected the patient should be treated according to ABCDE principles and oxygen should be administered. In case of neurological or circulatory symptoms a hospital that could provide hyperbaric oxygen therapy should be contacted as soon as possible.