Endothelial-to-Mesenchymal Transition in an Hereditary Hemorrhagic Telangiectasia-like Pediatric Case of Multiple Pulmonary Arteriovenous Malformations.

Pulmonary arteriovenous malformations (PAVMs) are vascular anomalies resulting in abnormal connections between pulmonary arteries and veins. In 80% of cases, PAVMs are present from birth, but clinical manifestations are rarely seen in childhood. These congenital malformations are typically associated with Hereditary Hemorrhagic Telangiectasia (HHT), a rare disease that affects 1 in 5000/8000 individuals. HHT disease is frequently caused by mutations in genes involved in the TGF-ß pathway. However, approximately 15% of patients do not have a genetic diagnosis and, among the genetically diagnosed, more than 33% do not meet the Curaçao criteria. This makes clinical diagnosis even more challenging in the pediatric age group. Here, we introduce an 8-year-old patient bearing a severe phenotype of multiple diffuse PAVMs caused by an unknown mutation which ended in lung transplantation. Phenotypically, the case under study follows a molecular pattern which is HHT-like. Therefore, molecular- biological and cellular-functional analyses have been performed in primary endothelial cells (ECs) isolated from the explanted lung. The findings revealed a loss of functionality in lung endothelial tissue and a stimulation of endothelial-to-mesenchymal transition. Understanding the molecular basis of this transition could potentially offer new therapeutic strategies to delay lung transplantation in severe cases.

Pulmonary vein thrombosis: Clinical presentation and outcomes.

BACKGROUND: Pulmonary vein thrombosis (PVT) is a rare thromboembolic disease with potential high-risk complications related to arterial embolization, but little is known regarding risk factors and outcomes. OBJECTIVE: To describe the etiology, management, and clinical course of PVT. METHODS: Institutional health records were queried (1/1/2001-12/30/2023) to identify patients ≥18 years of age diagnosed with PVT. Thrombosis, bleeding, respiratory failure, and all-cause mortality were analyzed. Suspected tumor thrombus cases were excluded. RESULTS: 72 patients with PVT were identified (median age 62 years, 50 % female), and PVT was overall rare at 3.1 diagnosed cases per year at our institution. PVT primarily affected a single vein (89 %), most commonly the left upper PV (40 %). Of these, 37 % occurred while on therapeutic anticoagulation. The most common risk factors included cancer (55 %) and related surgical lobectomy (21 %). Extrinsic vein compression (17 %) and recent surgery (19 %) were also common; 19 % were deemed idiopathic. Most patients (76 %) were treated with anticoagulation and frequently indefinite duration (80 %). During a median follow-up of 11.7 months (IQR 39.5 months), serial imaging (available for 68 %) revealed PVT resolution in 64 %. Four-year Kaplan-Meier probability of outcome included: left atrial thrombus (21 %), need for mechanical ventilation (14 %), pneumonia (9 %), and ischemic stroke (9 %). The mortality rate was 46 % with median survival 14 months after PVT diagnosis. CONCLUSION: PVT is often associated with active malignancy, lobectomy, recent surgery, and extrinsic vein compression; 1 in 5 cases were idiopathic. Notable complications include left atrial thrombus with arterial embolism including stroke. With anticoagulation, most thrombi resolve over time. Mortality rates are high, reflecting the high the prevalence of cancer.

Pulmonary vascular disease in Veterans with post-deployment respiratory syndrome.

Exertional dyspnea has been documented in US military personnel after deployment to Iraq and Afghanistan. We studied whether continued exertional dyspnea in this patient population is associated with pulmonary vascular disease (PVD). We performed detailed histomorphometry of pulmonary vasculature in 52 Veterans with biopsy-proven post-deployment respiratory syndrome (PDRS) and then recruited five of these same Veterans with continued exertional dyspnea to undergo a follow-up clinical evaluation, including symptom questionnaire, pulmonary function testing, surface echocardiography, and right heart catheterization (RHC). Morphometric evaluation of pulmonary arteries showed significantly increased intima and media thicknesses, along with collagen deposition (fibrosis), in Veterans with PDRS compared to non-diseased (ND) controls. In addition, pulmonary veins in PDRS showed increased intima and adventitia thicknesses with prominent collagen deposition compared to controls. Of the five Veterans involved in our clinical follow-up study, three had borderline or overt right ventricle (RV) enlargement by echocardiography and evidence of pulmonary hypertension (PH) on RHC. Together, our studies suggest that PVD with predominant venular fibrosis is common in PDRS and development of PH may explain exertional dyspnea and exercise limitation in some Veterans with PDRS.

Structural and electro-anatomical characterization of the equine pulmonary veins: implications for atrial fibrillation.

INTRODUCTION/OBJECTIVES: Spontaneous pulmonary vein (PV) activity triggers atrial fibrillation (AF) in humans. Although AF frequently occurs in horses, the origin remains unknown. This study investigated the structural and electro-anatomical properties of equine PVs to determine the potential presence of an arrhythmogenic substrate. ANIMALS, MATERIALS AND METHODS: Endocardial three-dimensional electro-anatomical mapping (EnSite Precision) using high-density (HD) catheters was performed in 13 sedated horses in sinus rhythm. Left atrium (LA) access was obtained retrogradely through the carotid artery. Post-mortem, tissue was harvested from the LA, right atrium (RA), and PVs for histological characterization and quantification of ion channel expression using immunohistochemical analysis. RESULTS: Geometry, activation maps, and voltage maps of the PVs were created and a median of four ostia were identified. Areas of reduced conduction were found at the veno-atrial junction. The mean myocardial sleeve length varied from 28 ± 13 to 49 ± 22 mm. The PV voltage was 1.2 ± 1.4 mV and lower than the LA (3.4 ± 0.9 mV, P < 0.001). The fibrosis percentage was higher in PV myocardium (26.1 ± 6.6%) than LA (14.5 ± 5.0%, P = 0.003). L-type calcium channel (CaV1.2) expression was higher in PVs than LA (P = 0.001). T-type calcium channels (CaV3.3), connexin-43, ryanodine receptor-2, and small conductance calcium-activated potassium channel-3 was expressed in PVs. CONCLUSIONS: The veno-atrial junction had lower voltages, increased structural heterogeneity and areas of slower conduction. Myocardial sleeves had variable lengths, and a different ion channel expression compared to the atria. Heterogeneous properties of the PVs interacting with the adjacent LA likely provide the milieu for re-entry and AF initiation.

Robotic-assisted right upper lobectomy with systemic pulmonary vein anomaly: a case report.

BACKGROUND: While the role of low-dose computed tomography (CT) in lung cancer screening is established, its limitations in detailing pulmonary vascular variations are less emphasized. Three-dimensional reconstruction technology allows surgeons to reconstruct a patient's bronchial and pulmonary vascular structures using CT scan results. However, low-dose CT may not provide the same level of clarity as enhanced CT in displaying pulmonary vascular details. This limitation can be unfavorable for preoperative detection of potential pulmonary vascular variations, especially in cases involving planned segmentectomy. CASE PRESENTATION: We report a case of a 58-year-old female with lung cancer, initially planned for Da Vinci robot-assisted thoracoscopic segmentectomy. Unexpectedly, during surgery, a pulmonary vein variation in the right upper lobe was discovered, leading to a change in the surgical method to a lobectomy. The patient had four variant right upper lobe veins draining into the superior vena cava and one into the left atrium. The surgery was complicated by significant bleeding and postoperative pulmonary congestion. Postoperative pathology confirmed adenocarcinoma. CONCLUSIONS: This case highlights the importance of meticulous intraoperative exploration, particularly in cases involving planned segmentectomy, as unexpected pulmonary vein variations can significantly affect surgical decision-making. While three-dimensional reconstruction based on preoperative CT data is a valuable tool, it may not capture the full complexity of the anatomical variations. We discuss potential preoperative imaging techniques, including contrast-enhanced CT and CT angiography, as methods to better identify these variations. The enhanced visualization provided by robot-assisted surgery plays a crucial role in identifying and adapting to these variations, underscoring the advantages of this surgical approach. Our report contributes to the existing literature by providing a detailed account of how these principles were applied in a real-world scenario, reinforcing the need for surgical adaptability and awareness of the limitations of low-dose CT in complex cases.

Strong desmin immunoreactivity in the myocardial sleeves around pulmonary veins, superior caval vein and coronary sinus supports the presumed arrhythmogenicity of these regions.

Myocardial sleeve around human pulmonary veins plays a critical role in the pathomechanism of atrial fibrillation. Besides the well-known arrhythmogenicity of these veins, there is evidence that myocardial extensions into caval veins and coronary sinus may exhibit similar features. However, studies investigating histologic properties of these structures are limited. We aimed to investigate the immunoreactivity of myocardial sleeves for intermediate filament desmin, which was reported to be more abundant in Purkinje fibers than in ventricular working cardiomyocytes. Sections of 16 human (15 adult and 1 fetal) hearts were investigated. Specimens of atrial and ventricular myocardium, sinoatrial and atrioventricular nodes, pulmonary veins, superior caval vein and coronary sinus were stained with anti-desmin monoclonal antibody. Intensity of desmin immunoreactivity in different areas was quantified by the ImageJ program. Strong desmin labeling was detected at the pacemaker and conduction system as well as in the myocardial sleeves around pulmonary veins, superior caval vein, and coronary sinus of adult hearts irrespective of sex, age, and medical history. In the fetal heart, prominent desmin labeling was observed at the sinoatrial nodal region and in the myocardial extensions around the superior caval vein. Contrarily, atrial and ventricular working myocardium exhibited low desmin immunoreactivity in both adults and fetuses. These differences were confirmed by immunohistochemical quantitative analysis. In conclusion, this study indicates that desmin is abundant in the conduction system and venous myocardial sleeves of human hearts.

Surgery for fibrosing mediastinitis with severe pulmonary hypertension due to pulmonary venous stenosis.

A 21-year-old woman with severe pulmonary hypertension and circulatory collapse was referred to our hospital for possible lung transplantation with extracorporeal membrane oxygenation support. Computed tomography revealed severe stenosis of all 4 pulmonary veins, and fibrosing mediastinitis was suspected. Surgical reconstruction of the pulmonary veins was performed, and extracorporeal membrane oxygenation support was weaned off. After surgery, pulmonary vascular resistance normalized. This successful case demonstrates that surgical pulmonary venous reconstruction is an important treatment for fibrosing mediastinitis induced by pulmonary venous stenosis and pulmonary hypertension.

Three-dimensional imaging anatomical research and clinical implications of V1 +2 d in the left upper lung.

BACKGROUND: To investigate the distribution pattern of V1+2 d in the left superior pulmonary vein and its clinical significance. METHODS: A retrospective analysis was conducted using three-dimensional computed tomographic bronchography and angiography (3D-CTBA) data from 500 lung cancer patients. Statistical analyses were performed to evaluate the incidence and drainage patterns of the three sub-branches of V1+2 d, namely V1+2 d1, V1+2 d2 and V1+2 d3. Furthermore, clinical data from 10 patients' lesions involving V1+2 d were reviewed to illustrate the impact of adjacency to V1+2 d on the surgical approach. RESULTS: The incidences of V1+2 d1, V1+2 d2 and V1+2 d3 were 100%, 76.4% and 100% respectively. The relative interlobar distribution sizes of B3 a and B1+2 c and the left upper division (LUD) vein type influenced the incidence of V1+2 d2 (p < 0.05; p < 0.001). V1+2 d2 predominantly occurred in B3 a = B1+2 c and B1+2 c > B3 a patterns. V1+2 d2 was entirely absent in the B3 a > B1+2 c pattern. V1+2 d2 exhibited a higher incidence in both the central vein (CV) type and the noncentral vein (NCV) type when compared to the semi-central vein (SCV) type (100% vs. 100% vs. 64.8%). The most prevalent venous drainage pattern was the three sub-branches of V1+2 d constituting a major trunk to drain (41.2%). All 10 cases with lesions involving V1+2 d successfully underwent sublobar resection with no complications, and the surgical margin was ≥2 cm. CONCLUSIONS: The three sub-branches of V1+2 d exhibit a high incidence with diverse distribution patterns, yet a discernible pattern exists. For inter- or multi-intersegmental nodules involving V1+2 d, combined segmentectomy and subsegmentectomy or combined subsegmentectomy can ensure the safe margin.

Pulsed field ablation for pulmonary vein isolation: Preclinical safety and effectiveness of a novel hexaspline ablation catheter.

BACKGROUND: Pulsed-field ablation (PFA) has emerged as a nonthermal energy source for cardiac ablation, with potential safety advantages over radiofrequency ablation (RFA) and cryoballoon ablation. OBJECTIVE: To report the preclinical results of a novel hexaspline PFA catheter for pulmonary vein isolation (PVI), and to verify the influence of PFA on esophagus by comparing with RFA. METHODS: This study included a total of 15 canines for the efficacy and safety study and four swine for the esophageal safety study. The 15 canines were divided into an acute cohort (n = 3), a 30-day follow-up cohort (n = 5) and a 90-day follow-up cohort (n = 7), PVI was performed with the novel hexaspline PFA ablation catheter. In the esophageal safety study, four swine were divided into PFA cohort (n = 2) and RFA cohort (n = 2), esophageal injury swine model was adopted, the esophagus was intubated with an esophageal balloon retractor, under fluoroscopy, the DV8 device was inflated with a mixture of saline and contrast and rotated to displace the esophagus rightward and anteriorly toward the ablation catheter in the inferior vena cava (IVC) and right inferior pulmonary vein (PV). Nine PFA applications were delivered at four locations on IVC and two locations on the right inferior PV in the PFA cohort, six RFA applications were delivered at each location in the RFA group. Histopathological analysis of all PVs, esophagus, IVC, and the adjacent lungs was performed. RESULTS: Acute PV isolation was achieved in all 15 canines (100%), with energy delivery times of less than 3 min/animal. In the 30 and 90 days group, the overall success rates were 88.9% and 88.5% per PVs, respectively. Two right superior pulmonary veins (RSPVs) in the 30-day group, two RSPVs and one left superior PV in the 90-day group with recovered potentials. At follow-up, gross pathological examination revealed the lesions around the PVs were continuous and transmural. Masson's trichrome staining revealed the myocardial cells in the PVs became fibrotic, but small arteries and nervous tissue were preserved. Results of swine esophageal injury model revealed the esophageal luminal surface was smooth and without evidence for esophageal injury in the PFA group, whereas obvious ulceration was detected on the esophagus tunica mucosa in the RFA group. CONCLUSION: In the chronic canine study, PFA-based PVI were safe and effective with demonstrable sparing of nerves and venous tissue. Compared with RFA, there was also good evidence for safety of PFA, avoiding PV stenosis and esophageal injury. This preclinical study provided the scientific basis for the first-in-human endocardial PFA studies.

Effect of fibrosis regionality on atrial fibrillation recurrence: insights from DECAAF II.

AIMS: The amount of fibrosis in the left atrium (LA) predicts atrial fibrillation (AF) recurrence after catheter ablation (CA). We aim to identify whether regional variations in LA fibrosis affect AF recurrence. METHODS AND RESULTS: This post hoc analysis of the DECAAF II trial includes 734 patients with persistent AF undergoing first-time CA who underwent late gadolinium enhancement magnetic resonance imaging (LGE-MRI) within 1 month prior to ablation and were randomized to MRI-guided fibrosis ablation in addition to standard pulmonary vein isolation (PVI) or standard PVI only. The LA wall was divided into seven regions: anterior, posterior, septal, lateral, right pulmonary vein (PV) antrum, left PV antrum, and left atrial appendage (LAA) ostium. Regional fibrosis percentage was defined as a region's fibrosis prior to ablation divided by total LA fibrosis. Regional surface area percentage was defined as an area's surface area divided by the total LA wall surface area before ablation. Patients were followed up for a year with single-lead electrocardiogram (ECG) devices. The left PV had the highest regional fibrosis percentage (29.30 ± 14.04%), followed by the lateral wall (23.23 ± 13.56%), and the posterior wall (19.80 ± 10.85%). The regional fibrosis percentage of the LAA was a significant predictor of AF recurrence post-ablation (odds ratio = 1.017, P = 0.021), and this finding was only preserved in patients receiving MRI-guided fibrosis ablation. Regional surface area percentages did not significantly affect the primary outcome. CONCLUSION: We have confirmed that atrial cardiomyopathy and remodelling are not a homogenous process, with variations in different regions of the LA. Atrial fibrosis does not uniformly affect the LA, and the left PV antral region has more fibrosis than the rest of the wall. Furthermore, we identified regional fibrosis of the LAA as a significant predictor of AF recurrence post-ablation in patients receiving MRI-guided fibrosis ablation in addition to standard PVI.

The 100 most cited papers on total anomalous pulmonary venous connection: a bibliometric analysis.

BACKGROUND: The number of citations a paper receives reflects its impact on the scientific community. We aimed to identify and explore the characteristics of the most cited papers on total anomalous pulmonary venous connection (TAPVC). METHODS: Web of Science Core Collection Expanded Science Citation Index (1900 to present) was searched and papers on TAPVC were reviewed. Articles were ranked by the number of citations and the 100 most cited papers were analyzed. RESULTS: The 100 most cited papers were published between 1952 and 2018 with a mean number of citations of 52 (range 26 to 148). The 1990s was the most productive decade. All articles except one were written in English. The 100 most cited articles were published in 24 journals, led by Journal of Thoracic and Cardiovascular Surgery (21 articles), followed by Annals of Thoracic Surgery (20 articles), and Circulation (16 articles). The United States of America contributed most of the 100 most cited papers (60 articles). Hospital for Sick Children, Toronto led the list of citation classics with six papers. Christopher A. Caldarone, John W. Kirklin, and P. E. F. Daubeney were the most productive authors with 3 articles each. More than half of the papers were cohort studies (51 articles). Surgery, radiology and etiology were the main topics. Thirty-one articles were funded by public foundations, and none received support from commercial companies. CONCLUSIONS: The bibliometric analysis gives a historical perspective on scientific progress in the field of TAPVC and lays the foundation for future research.

Metastatic lung tumor from hepatocellular carcinoma with tumor thrombus invasion in the pulmonary vein: a case report.

BACKGROUND: Metastatic lung tumor with a tumor thrombus in the peripheral pulmonary vein is very rare. We present a case of a metastatic lung tumor from hepatocellular carcinoma (HCC) with tumor thrombus invasion in the pulmonary vein that was diagnosed preoperatively and underwent complete resection by segmentectomy. CASE PRESENTATION: A 77-year-old man underwent laparoscopic lateral segment hepatectomy for HCC eight years ago. Protein induced by vitamin K absence or antagonist-II remained elevated from two years ago. Contrast-enhanced chest computed-tomography (CT) showed a 27 mm nodule in the right apical segment (S1). He was pathologically diagnosed with a metastatic lung tumor from HCC via transbronchoscopic biopsy. We planned to perform right S1 segmentectomy. Before surgery, contrast-enhanced CT in the pulmonary vessels phase for three-dimensional reconstruction showed that the tumor extended into the adjusting peripheral pulmonary vein, and we diagnosed tumor thrombus invasion in V1a. The surgery was conducted under 3-port video-assisted thoracic surgery. First, V1 was ligated and cut. A1 and B1 were cut. The intersegmental plane was cut with mechanical staplers. Pathological examination revealed moderately-differentiated metastatic HCC with tumor thrombus invasions in many pulmonary veins, including V1a. No additional postoperative treatments were performed. CONCLUSIONS: As malignant tumors tend to develop a tumor thrombus in the primary tumor, it might be necessary to perform contrast-enhanced CT in the pulmonary vessel phase to check for a tumor thrombus before the operation for metastatic lung tumors.

Preclinical assessment of the feasibility, safety and lesion durability of a novel 'single-shot' pulsed field ablation catheter for pulmonary vein isolation.

AIMS: Single-shot pulmonary vein isolation can improve procedural efficiency. To assess the capability of a novel, expandable lattice-shaped catheter to rapidly isolate thoracic veins using pulsed field ablation (PFA) in healthy swine. METHODS AND RESULTS: The study catheter (SpherePVI; Affera Inc) was used to isolate thoracic veins in two cohorts of swine survived for 1 and 5 weeks. In Experiment 1, an initial dose (PULSE2) was used to isolate the superior vena cava (SVC) and the right superior pulmonary vein (RSPV) in six swine and the SVC only in two swine. In Experiment 2, a final dose (PULSE3) was used for SVC, RSPV, and left superior pulmonary vein (LSPV) in five swine. Baseline and follow-up maps, ostial diameters, and phrenic nerve were assessed. Pulsed field ablation was delivered atop the oesophagus in three swine. All tissues were submitted for pathology. In Experiment 1, all 14/14 veins were isolated acutely with durable isolation demonstrated in 6/6 RSPVs and 6/8 SVC. Both reconnections occurred when only one application/vein was used. Fifty-two and 32 sections from the RSPVs and SVC revealed transmural lesions in 100% with a mean depth of 4.0 ± 2.0 mm. In Experiment 2, 15/15 veins were isolated acutely with 14/15 veins (5/5 SVC, 5/5 RSPV, and 4/5 LSPV) durably isolated. Right superior pulmonary vein (31) and SVC (34) sections had 100% transmural, circumferential ablation with minimal inflammation. Viable vessels and nerves were noted without evidence of venous stenosis, phrenic palsy, or oesophageal injury. CONCLUSION: This novel expandable lattice PFA catheter can achieve durable isolation with transmurality and safety.

Magnetic resonance assessment of left atrial scar formation following a novel very high-power short-duration workflow for atrial fibrillation ablation.

AIMS: Atrial fibrillation (AF) ablation protocols using energy delivery with very high power and short duration (vHPSD) have been introduced to improve lesion formation. This study reports procedural data of vHPSD ablation in AF patients and analyses characteristics of ablation-induced left atrial (LA) scar formation from cardiac magnetic resonance imaging (MRI). METHODS AND RESULTS: Sixty consecutive patients undergoing index pulmonary vein isolation following our institutional Q4U-AF workflow were prospectively enrolled. Ablation was conducted using a contact force sensing catheter allowing for vHPSD ablation using a temperature-controlled ablation mode. Thirty patients underwent cardiac late gadolinium enhancement MRI of the LA 3 months after ablation to assess LA scar. Mean procedural duration was 66.5 ± 14.8 min. Mean ablation time was 4.7 ± 0.9 min with a mean number of 69.9 ± 14.2 applications. First-pass isolation was achieved in 51 patients (85%) for the right pulmonary veins (RPVs), in 37 patients (61.7%) for the left pulmonary veins (LPVs), and in 34 patients (56.7%) for both pulmonary veins (PVs). Magnetic resonance imaging at 3 months post-ablation demonstrated a mean scar width of 14.4 ± 2.6 mm around RPVs and 11.9 ± 1.9 mm at LPVs (P > 0.05). Complete PV encirclement was observed in 76.7% for RPVs, in 76.7% for LPVs, and in 66.7% for both PV pairs. During a mean follow-up of 4.7 ± 1.4 months, arrhythmia recurrence was observed in 3.3% of the patients. CONCLUSION: Pulmonary vein isolation following a novel vHPSD workflow resulted in short procedure duration and high acute and mid-term efficacy. Magnetic resonance imaging demonstrated durable and transmural PV lesions with homogeneous and contiguous scar formation.

An Incidental Discovery of Supracardiac Left-sided Partial Anomalous Pulmonary Connection and Dilation of the Azygos Vein Detected in Adulthood.

INTRODUCTION: Anomalous pulmonary venous connection is a rare congenital variant of the pulmonary veins drained into the right atrium. The left-side partial anomalous pulmonary connections are usually detected in adulthood and occasionally drain into the left brachiocephalic vein. CASE DESCRIPTION: An asymptomatic 63-year-old woman with a known history of left carotid body paraganglioma was admitted to our institution to evaluate this tumor by computed tomography angiography of the neck and brain. As an incidental finding, CTA demonstrated a supracardiac partial anomalous pulmonary venous connection between the left upper pulmonary vein and the left innominate via the vertical vein. Additionally, dilation of the azygos vein was observed. CONCLUSION: Supracardiac left-sided partial anomalous pulmonary venous connection is a rare vascular variant, usually asymptomatic and found incidentally in adults.

Lattice-tip catheter for single-shot pulmonary vein isolation with pulsed field ablation.

BACKGROUND: A compressible lattice-tip catheter designed for focal ablation using radiofrequency or pulsed-field energies has been recently described. The objective of this study is to describe a new lattice catheter designed for single-shot pulmonary vein isolation (PVI). METHODS: This 8F catheter consists of a compressible lattice tip that is delivered over the wire and is expandable up to 34 mm (SpherePVI™, Affera Inc.). Pulsed field ablation (PFA) was applied from 6 elements using a biphasic waveform of microsecond scale (± 1.3-2.0 kV, 5 s per application). In 12 swine, the superior vena cava (SVC) and right superior pulmonary vein (RSPV) were targeted for isolation. Animals were survived for 12-24 h (n = 6) or 3 weeks (n = 6) for evaluation of short and long-term safety and efficacy parameters. PVI was evaluated immediately after ablation and at the terminal procedure. Ablation-related microbubbles were examined using intracardiac echocardiography and phrenic nerve function by pacing. The tissue was examined by histopathology. RESULTS: In all 12 animals, PFA resulted in successful acute isolation of the SVC and RSPV using 2.8 ± 1.1 and 3.2 ± 1.2 applications per vein, respectively. After a survival period of 23 ± 5.9 days, all targeted veins remained isolated, and the level of isolation persisted without significant regression or expansion. In one animal, SVC isolation at the level of the right atrial appendage resulted in sinus node arrest. PFA did not affect phrenic nerve function, and it was associated with a few isolated bubbles formation. CONCLUSIONS: In this pre-clinical study, a new expandable lattice catheter designed for single-shot PVI was able to achieve rapid and durable isolation.

Ultrasound findings in neonates with alveolar capillary dysplasia with misalignment of the pulmonary veins: report of two cases.

Alveolar capillary dysplasia with misalignment of the pulmonary veins (ACDMPV) is a rare congenital pulmonary disease that affects newborns. Most patients with ACDMPV are born at full term and are healthy. The main clinical manifestations are refractory pulmonary hypertension and pulmonary failure with gastrointestinal, urinary, or cardiac malformations. ACDMPV often progresses rapidly, but no conventional biological or imaging tests other than genetic testing are available for its diagnosis. Lung biopsy is currently the gold standard for diagnosis. We herein report two cases of ACDMPV confirmed by pathological examination and discuss their ultrasonographic findings.

Human Pulmonary Vein Myocardial Sleeve Autonomic Neural Density and Cardiovascular Mortality.

Myocardial sleeves around pulmonary veins (PVs) are highly innervated structures with heterogeneous morphological and electrophysiological characteristics. Autonomic nerve dysfunction in the myocardium may be associated with an increased risk of cardiovascular morbidity and mortality. This article studied autonomic neural remodeling in myocardial sleeves around PVs and atrial-PV ostia with immunohistochemical and morphometric methods with clinicopathological correlations. PVs were collected from 37 and atrial-PV ostia from 17 human autopsy hearts. Immunohistochemical analysis was performed using antibodies against tyrosine hydroxylase (TH), choline acetyltransferase (CHAT), and growth-associated protein 43 (GAP43). In the PV cohort, subjects with immediate cardiovascular cause of death had significantly decreased sympathetic nerve density in fibro-fatty tissue vs those with non-cardiovascular cause of death (1624.53 vs 2522.05 µm2/mm2, p=0.038). In the atrial-PV ostia cohort, parasympathetic nerve density in myocardial sleeves was significantly increased in subjects with underlying cardiovascular cause of death (19.48 µm2/mm2) than subjects with underlying non-cardiovascular cause of death with no parasympathetic nerves detected (p=0.034). Neural growth regionally varied in sympathetic nerves and was present in most of the parasympathetic nerves. Heterogeneous autonomic nerve distribution and growth around PVs and atrial-PV ostia might play a role in cardiovascular morbidity and mortality. No association in nerve density was found with atrial fibrillation.

Feasibility of Single-Shot Whole Thoracic Time-Resolved MR Angiography to Evaluate Patients with Multiple Pulmonary Arteriovenous Malformations.

OBJECTIVE: To evaluate the feasibility of single-shot whole thoracic time-resolved MR angiography (TR-MRA) to identify the feeding arteries of pulmonary arteriovenous malformations (PAVMs) and reperfusion of the lesion after embolization in patients with multiple PAVMs. MATERIALS AND METHODS: Nine patients (8 females and 1 male; age range, 23-65 years) with a total of 62 PAVMs who underwent percutaneous embolization for multiple PAVMs and were subsequently followed up using TR-MRA and CT obtained within 6 months from each other were retrospectively reviewed. All imaging analyses were performed by two independent readers blinded to clinical information. The visibility of the feeding arteries on maximum intensity projection (MIP) reconstruction and multiplanar reconstruction (MPR) TR-MRA images was evaluated by comparing them to CT as a reference. The accuracy of TR-MRA for diagnosing reperfusion of the PAVM after embolization was assessed in a subgroup with angiographic confirmation. The reliability between the readers in interpreting the TR-MRA results was analyzed using kappa (κ) statistics. RESULTS: Feeding arteries were visible on the original MIP images of TR-MRA in 82.3% (51/62) and 85.5% (53/62) of readers 1 and 2, respectively. Using the MPR, the rates increased to 93.5% (58/62) and 95.2% (59/62), respectively (κ = 0.760 and 0.792, respectively). Factors for invisibility were the course of feeding arteries in the anteroposterior plane, proximity to large enhancing vessels, adjacency to the chest wall, pulsation of the heart, and small feeding arteries. Thirty-seven PAVMs in five patients had angiographic confirmation of reperfusion status after embolization (32 occlusions and 5 reperfusions). TR-MRA showed 100% (5/5) sensitivity and 100% (32/32, including three cases in which the feeding arteries were not visible on TR-MRA) specificity for both readers. CONCLUSION: Single-shot whole thoracic TR-MRA with MPR showed good visibility of the feeding arteries of PAVMs and high accuracy in diagnosing reperfusion after embolization. Single-shot whole thoracic TR-MRA may be a feasible method for the follow-up of patients with multiple PAVMs.