Safety Window for Effective Lesion Crossing in Patients With Chronic Thromboembolic Pulmonary Hypertension.

Background: Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension (CTEPH) is limited by a lack of safe and effective tools for crossing these lesions. We aim to identify a safety window for an intraluminal crossing device in this vascular bed by studying the piercing properties of pulmonary arterial vessel walls and intraluminal CTEPH lesion specimens. As a secondary objective, we also describe the histopathologic features of CTEPH lesions. Methods: Specimens were procured from 9 patients undergoing pulmonary endarterectomy. The specimens were subsampled and identified grossly as arterial wall or intraluminal CTEPH lesions. The force needed for tissue penetration was measured using a 0.38-mm (0.015-in) diameter probe in an ex vivo experimental model developed in our lab. Concurrent histology was also performed. Results: The mean force needed to penetrate the arterial wall and intraluminal CTEPH lesions was 1.75 ± 0.10 N (n = 121) and 0.30 ± 0.04 N (n = 56), respectively (P < .001). Histology confirmed the presence of intimal hyperplasia with calcium and hemosiderin deposition in the arterial wall as well as an old, organized thrombus in the lumen. Conclusions: The pulmonary arterial wall is friable and prone to perforation during instrumentation with workhorse coronary guide wires. However, the results of this study demonstrate that a much lower force is needed for the 0.38-mm (0.015-in) probe to penetrate an intraluminal CTEPH lesion compared to pulmonary arterial intima. This finding suggests the existence of a safety window for lesion-crossing devices, enabling effective balloon pulmonary angioplasty.

ACR Appropriateness Criteria® Preprocedural Planning for Left Atrial Procedures in Atrial Fibrillation.

This document summarizes the relevant literature for the selection of preprocedural imaging in three clinical scenarios in patients needing endovascular treatment or cardioversion of atrial fibrillation. These clinical scenarios include preprocedural imaging prior to radiofrequency ablation; prior to left atrial appendage occlusion; and prior to cardioversion. The appropriateness of imaging modalities as they apply to each clinical scenario is rated as usually appropriate, may be appropriate, and usually not appropriate to assist the selection of the most appropriate imaging modality in the corresponding clinical scenarios. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

NASCI case of the month: "Unroofed coronary sinus without persistent left-sided superior vena cava".

Unroofed sinus is categorized into four subtypes. Types I and II represent complete unroofing with or without an LSVC, respectively [1]. Types III and IV are partial unroofing involving the mid-CS (type III) or near the LA appendage and left superior pulmonary vein (type IV) [1]. CT has advantages over echocardiography in detection of this anomaly (illustrated in this case) as well as in precise delineation of defect and associated findings (presence or absence of LSVC). Short axis reconstructions at the level of CS are helpful in diagnosis. Considerations for repair include location of CS defect, presence of LSVC and other abnormalities as well as comorbidity risks [2].

Coronary Artery Disease: Role of Computed Tomography and Recent Advances.

In this review, the authors summarize the role of coronary computed tomography angiography and coronary artery calcium scoring in different clinical presentations of chest pain and preventative care and discuss future directions and new technologies such as pericoronary fat inflammation and the growing footprint of artificial intelligence in cardiovascular medicine.

Imaging Features of Arrhythmogenic Cardiomyopathies.

Arrhythmogenic cardiomyopathy (ACM) is a genetic disease characterized by replacement of ventricular myocardium with fibrofatty tissue, predisposing the patient to ventricular arrhythmias and/or sudden cardiac death. Most cases of ACM are associated with pathogenic variants in genes that encode desmosomal proteins, an important cell-to-cell adhesion complex present in both the heart and skin tissue. Although ACM was first described as a disease predominantly of the right ventricle, it is now acknowledged that it can also primarily involve the left ventricle or both ventricles. The original right-dominant phenotype is traditionally diagnosed using the 2010 task force criteria, a multifactorial algorithm divided into major and minor criteria consisting of structural criteria based on two-dimensional echocardiographic, cardiac MRI, or right ventricular angiographic findings; tissue characterization based on endomyocardial biopsy results; repolarization and depolarization abnormalities based on electrocardiographic findings; arrhythmic features; and family history. Shortfalls in the task force criteria due to the modern understanding of the disease have led to development of the Padua criteria, which include updated criteria for diagnosis of the right-dominant phenotype and new criteria for diagnosis of the left-predominant and biventricular phenotypes. In addition to incorporating cardiac MRI findings of ventricular dilatation, systolic dysfunction, and regional wall motion abnormalities, the new Padua criteria emphasize late gadolinium enhancement at cardiac MRI as a key feature in diagnosis and imaging-based tissue characterization. Conditions to consider in the differential diagnosis of the right-dominant phenotype include various other causes of right ventricular dilatation such as left-to-right shunts and variants of normal right ventricular anatomy that can be misinterpreted as abnormalities. The left-dominant phenotype can mimic myocarditis at imaging and clinical examination. Additional considerations for the differential diagnosis of ACM, particularly for the left-dominant phenotype, include sarcoidosis and dilated cardiomyopathy. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Integrative analysis of multimodal patient data identifies personalized predictors of tuberculosis treatment prognosis.

Tuberculosis (TB) afflicted 10.6 million people in 2021, and its global burden is increasing due to multidrug-resistant TB (MDR-TB) and extensively resistant TB (XDR-TB). Here, we analyze multi-domain information from 5,060 TB patients spanning 10 countries with high burden of MDR-TB from the NIAID TB Portals database to determine predictors of TB treatment outcome. Our analysis revealed significant associations between radiological, microbiological, therapeutic, and demographic data modalities. Our machine learning model, built with 203 features across modalities outperforms models built using each modality alone in predicting treatment outcomes, with an accuracy of 83% and area under the curve of 0.84. Notably, our analysis revealed that the drug regimens Bedaquiline-Clofazimine-Cycloserine-Levofloxacin-Linezolid and Bedaquiline-Clofazimine-Linezolid-Moxifloxacin were associated with treatment success and failure, respectively, for MDR non-XDR-TB. Drug combinations predicted to be synergistic by the INDIGO algorithm performed better than antagonistic combinations. Our prioritized set of features predictive of treatment outcomes can ultimately guide the personalized clinical management of TB.

Detection of Severe Lung Infection on Chest Radiographs of COVID-19 Patients: Robustness of AI Models across Multi-Institutional Data.

The diagnosis of severe COVID-19 lung infection is important because it carries a higher risk for the patient and requires prompt treatment with oxygen therapy and hospitalization while those with less severe lung infection often stay on observation. Also, severe infections are more likely to have long-standing residual changes in their lungs and may need follow-up imaging. We have developed deep learning neural network models for classifying severe vs. non-severe lung infections in COVID-19 patients on chest radiographs (CXR). A deep learning U-Net model was developed to segment the lungs. Inception-v1 and Inception-v4 models were trained for the classification of severe vs. non-severe COVID-19 infection. Four CXR datasets from multi-country and multi-institutional sources were used to develop and evaluate the models. The combined dataset consisted of 5748 cases and 6193 CXR images with physicians' severity ratings as reference standard. The area under the receiver operating characteristic curve (AUC) was used to evaluate model performance. We studied the reproducibility of classification performance using the different combinations of training and validation data sets. We also evaluated the generalizability of the trained deep learning models using both independent internal and external test sets. The Inception-v1 based models achieved AUC ranging between 0.81 ± 0.02 and 0.84 ± 0.0, while the Inception-v4 models achieved AUC in the range of 0.85 ± 0.06 and 0.89 ± 0.01, on the independent test sets, respectively. These results demonstrate the promise of using deep learning models in differentiating COVID-19 patients with severe from non-severe lung infection on chest radiographs.

Safe and Effective Balloon Pulmonary Angioplasty in the Outpatient Setting: The Michigan Medicine Experience.

Background: Balloon pulmonary angioplasty (BPA) is currently performed at select centers worldwide, with the current standard of practice being postprocedural inpatient monitoring for 24 to 72 hours. We sought to evaluate the safety and efficacy of BPA in a cohort of patients with chronic thrombo-embolic pulmonary disease (CTEPD) and chronic thromboembolic pulmonary hypertension (CTEPH) and outline a protocol for implementation in the outpatient setting. Methods: All patients with distal, inoperable CTEPH, residual symptoms after pulmonary endarterectomy, or symptomatic CTEPD from July 1, 2020, to June 30, 2022, were evaluated by a multidisciplinary chronic thromboembolic pulmonary hypertension team for consideration of BPA. Patients undergoing each BPA session adhered to a regimented protocol developed and implemented at our institution. Safety and efficacy were retrospectively evaluated with a mean follow-up time of 8.5 months. Results: Eighteen patients underwent a total of 78 BPA sessions. Overall, there was a significant improvement in World Health Organization functional class and mean improvement in 6-minute walking distance of +67 m. Hemodynamic parameters significantly improved with a mean decrease in mean pulmonary artery pressure and pulmonary vascular resistance of 7.3 ± 5.8 mm Hg and 1.7 ± 1.5 Wood units, respectively (P <.05). Complication rates were low with 3 (3.9%) of 78 patients developing scant hemoptysis and 1 (1.3%) of 78 experiencing vascular injury requiring inpatient hospitalization. Conclusions: BPA is both safe and effective when implemented in the outpatient setting using a regimented protocol provided there are necessary contingencies in place.

Anatomical Variations in Pulmonary Arterial Branches in Patients Undergoing Evaluation for Chronic Thromboembolic Pulmonary Hypertension.

Background: Catheter-based interventions have emerged for both acute and chronic pulmonary thromboembolic disease. With this development and the need for segmental cannulation, anatomic understanding of pulmonary arterial segmental branch origination is important. We aim to describe the prevalence of different pulmonary arterial segmental branch origination patterns. Methods: This study included 179 consecutive patients who underwent bilateral nonselective invasive pulmonary angiography for the evaluation of chronic thromboembolic pulmonary hypertension. Results: In our study population (age, 59.0 ± 14.8 years, 55.3% female, 71% White), we found several anatomic variations of branches to the different lobes. These included 7 branching patterns in the right upper lobe, 3 in the right middle lobe, and 10 in the right lower lobe (4 patterns for the origin of the superior segmental artery and 6 for the origin of the basilar segmental arteries). On the left side, we found 8 patterns in the left upper lobe, with 5 involving lingular branches, and 9 in the left lower lobe (5 for the origin of the superior segmental artery and 4 for the basilar segmental pulmonary arteries). Although there were many variations, only 2-3 variations for each individual lobe accounted for >90% of the angiograms. Conclusions: Up to 3 anatomic branching patterns per lobe were noted to account for >90% of pulmonary artery branching variations in this study. This knowledge is not only useful for the interventionalist performing catheter-directed therapies but also for future research efforts that aim to standardize reporting of pulmonary angiographic findings.

Interventional Imaging Roadmap to Successful Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Hypertension.

Balloon pulmonary angioplasty (BPA) is an evolving treatment modality for patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are not candidates for pulmonary endarterectomy. Although several imaging modalities currently exist for evaluating CTEPH, their individual use, specifically in the clinical practice of BPA, has not been well described. In this article, we provide a preprocedural, intraprocedural, and postprocedural interventional imaging roadmap for safe and effective BPA performance in routine clinical practice. Preprocedural assessment includes transthoracic echocardiography for right ventricular assessment, ventilation/perfusion scan to identify pulmonary segments with the highest degree of hypoperfusion, cross-sectional chest imaging excluding alternative causes of mismatched defects and providing anatomic and perfusion imaging concurrently, and nonselective invasive pulmonary angiography for risk stratification of individual lesion subtypes. Intraprocedural assessment includes subselective segmental angiography (SSA) for delineating segmental and subsegmental branch anatomy, lesion identification, and vessel sizing. Intravascular ultrasound and optical coherence tomography serve as adjunctive intraprocedural tools for more accurate vessel sizing and lesion characterization when SSA alone is insufficient. Postprocedural considerations include chest radiography to monitor for immediate postprocedure complications and echocardiography for the interval assessment of the right ventricle on longer-term follow-up.