Imaging and Surgical Treatment of Primary Pulmonary Artery Sarcoma Abstract Primary pulmonary artery sarcoma is a rare tumor originating from the pulmonary artery tree. Given the low incidence, few centers have reported on more than a handful of cases. Because of its rarity it is also commonly misdiagnosed as pulmonary embolism. Multi-modality diagnostic imaging and recognition of specific imaging characteristics along with a high index of suspicion is required to make the correct diagnosis and expedite treatment. The primary imaging modality for most cardiac tumors such as primary pulmonary artery sarcoma is now MRI. It provides superb spatial resolution as well as functional assessment of the heart and pulmonary circulation. CT imaging also is part of routing imaging and remains as the most pertinent imaging modality to evaluate the lung parenchyma and presence of metastatic disease. Here we review the pertinent imaging modalities and tissue characteristics that facilitate recognition of primary pulmonary artery sarcoma. We also provide a short overview of surgical resection and reconstruction, which is the mainstay therapy, for this rare tumor.

Topical issue: advanced imaging and endovascular treatment in pulmonary artery diseases

Role of cardiovascular magnetic resonance end-systolic 3D-SSFP sequence in repaired tetralogy of Fallot patients eligible for transcatheter pulmonary valve implantation Abstract To evaluate the usefulness of cardiovascular magnetic resonance (CMR) 3D steady state free precession (SSFP) sequence acquired at end-systole (ES) in repaired Tetralogy of Fallot (rToF) patients eligible for percutaneous pulmonary valve implantation (PPVI). Between 2012 and 2018, 78 rToF patients were selected for pulmonary valve replacement (PVR) according to CMR criteria. CMR protocol included 3D-SSFP sequence used to assess the right ventricle outflow tract (RVOT) diameters at three levels (pulmonary valve remnant, mid-portion, bifurcation) in mid-diastole (MD) or ES, RVOT length and coronary artery anatomy. In 20 rToF patients without indications for PVR (controls), 3D SSFP sequence was acquired at both cardiac phases (MD and ES) to evaluate RVOT dimension throughout the cardiac cycle. Invasive balloon sizing was recorded in patients undergoing PPVI. The 3D-SSFP sequence was performed in MD on 39 patients and in ES on other 39, of whom 26 patients met the criteria for PPVI. The latter was unsuccessful in ten patients (38%), mainly due (80% of cases) to significant size discrepancy at PV remnant and bifurcation levels (p = 0.019 and 0.037 respectively) between the measurements by 3D-SSFP in MD and those by the balloon size in systole. Significant RVOT size difference between MD and ES was present at mid-portion and bifurcation levels in the PVR candidate group, and at all three-levels in the control group (all p < 0.001). ES 3D-SSFP sequence is able to quantify RVOT dilation in rToF patients at its maximum expansion, thus improving selection of PPVI candidates.

Endovascular therapy for acute severe pulmonary embolism Abstract Acute pulmonary embolism (PE) is a major public health problem and accounts for 100,000–180,000 deaths per year in the United States. Current prognostic stratification separates acute PE into massive, submassive, and low-risk by the presence or absence of sustained hypotension, RV dysfunction, and myocardial necrosis. Massive, submassive and low-risk PE have mortality rates of 25–65%, 3%, and < 1%, respectively. In this review we will focus on therapies currently available to manage acute massive and submassive PE.

Feasibility and utility of dual-energy chest CTA for preoperative planning in pediatric pulmonary artery reconstruction Abstract The purpose of this study was to assess in pediatric pulmonary artery (PA) reconstruction candidates the feasibility and added utility of preoperative chest computed tomography angiography (CTA) using dual-energy technique, from which perfused blood volume (PBV)/iodine maps can be generated as a surrogate of pulmonary perfusion. Pediatric PA reconstruction patients were prospectively recruited for a new dose-neutral dual-energy CTA protocol. For each case, the severity of anatomic PA obstruction was graded by two pediatric cardiovascular radiologists in consensus using a modified Qanadli index. PBV maps were qualitatively reviewed and auto-segmented using Siemens syngo.via software. Associations between Qanadli scores and PBV were assessed with Spearman correlation (r) and ROC analysis. Effective radiation doses were estimated from dose-length product and ICRP 103 k-factors, using cubic Hermite spline interpolation. 19 patients were recruited with mean (SD) age of 6.0 (5.1), 11 (57.9%) female, 11 (73.7%) anesthetized. Higher QS correlated with lower PBV, both on a whole lung (r =  − 0.54, p < 0.001) and lobar (r =  − 0.50, p < 0.001) basis. The lung with lowest absolute PBV was predictive of the lung with highest Qanadli score, with AUC of 0.70 (95% CI 0.47–0.93). Qualitatively, PBV maps were heterogeneous, corresponding to multifocal PA stenoses, with decreased iodine content in areas of most severe obstruction. In conclusion, dual-energy chest CTA is feasible for pediatric PA reconstruction candidates. PBV maps show deficits in regions of more severe anatomic obstruction and may serve as a novel biomarker in this population.

Two-dimensional speckle tracking echocardiography assessed right ventricular function and exercise capacity in pre-capillary pulmonary hypertension Abstract Resting two-dimensional speckle tracking echocardiography (2D-STE) identified right ventricular (RV) systolic function were reported to predict exercise capacity in pulmonary hypertension (PH) patients, but little attention had been payed to 2D-STE detected RV diastolic function. Therefore, we aim to elucidate and compare the relations between 2D-STE identified RV diastolic/systolic functions and peak oxygen consumption (PVO2) determined by cardiopulmonary exercise testing (CPET) in pre-capillary PH. 2D-STE was performed in 66 pre-capillary PH patients and 28 healthy controls. Linear correlation and multivariate regression analyses were performed to evaluate and compare the relations between RV 2D-STE parameters and PVO2. Receiver operating characteristic curves were used to compare the predictive value of 2D-STE parameters in predicting the cut-off—PVO2 < 11 ml/min/kg. There were significant differences of all the 2D-STE parameters between PH patients and healthy controls. In patients, RV-peak global longitudinal strain (GLS, rs = − 0.498, P < 0.001), RV- peak systolic strain rate (GSRs, rs = − 0.537, P < 0.001) and RV- peak early diastolic strain rate (GSRe, rs = 0.527, P < 0.001) significantly correlated with PVO2, but no significant correlation was observed between RV- peak late diastolic strain rate (GSRa, rs = 0.208, P = 0.093) and PVO2. The first multivariate regression analysis of clinical data without echocardiographic parameters identified WHO functional class, NT-proBNP and BMI as independent predictors of PVO2 (Model-1, adjusted r2 = 0.421, P < 0.001); Then we added conventional echocardiographic parameters and 2D-STE parameters to the clinical data, identified S,(Model-2,adjusted r2 = 0.502, P < 0.001), RV-GLS (Model-3, adjusted r2 = 0.491, P < 0.001), RV-GSRe (Model-4, adjusted r2 = 0.500, P < 0.001) and RV-GSRs (Model-5, adjusted r2 = 0.519, P < 0.001) as independent predictors of PVO2, respectively. The predictive power was increased, and Model-5 including RV-GSRs showed the highest predictive capability. ROC curves found RV-GSRs expressed the strongest predictive value (AUC = 0.88, P < 0.001), and RV-GSRs > − 0.65/s had a 88.2% sensibility and 82.2% specificity to predict PVO2 < 11 ml/min/kg. 2D-STE assessed RV function improves the prediction of exercise capacity represented by PVO2 in pre-capillary PH. Graphical abstract

Advanced imaging in pulmonary hypertension: emerging techniques and applications Abstract Pulmonary hypertension (PH) is a pathophysiological disorder defined by an increase in pulmonary arterial pressure which can occur in multiple clinical conditions. Irrespective of etiology, PH entails a negative impact on exercise capacity and quality of life, and is associated with high mortality particularly in pulmonary arterial hypertension. Noninvasive imaging techniques play an important role in suggesting the presence of PH, providing noninvasive pulmonary pressure measurements, classifying the group of PH, identifying a possibly underlying disease, providing prognostic information and assessing response to treatment. While echocardiography, computed tomography (CT) and ventilation/perfusion scans are an integral part of routine work-up of patients with suspected PH according to current guidelines and across centers, innovative new techniques and applications in the field of PH such as 3D echocardiography, dual-energy CT, 4D flow magnetic resonance imaging (MRI), T1 and extracellular volume fraction mapping, non-contrast-enhanced MRI sequences for perfusion and ventilation assessment, and molecular-targeted positron emission tomography are emerging. This review discusses advanced and emerging imaging techniques in diagnosis, prognostic evaluation and follow-up of patients with PH.

Pulmonary arteriovenous malformations Abstract Pulmonary arteriovenous malformation, a condition most commonly associated with hereditary hemorrhagic telangiectasia, is an abnormal communication between the pulmonary artery and pulmonary vein without an intervening capillary communication. Although asymptomatic in ~ 50% individuals, it can present with the dreaded complications of stroke or intracranial abscess in high-risk individuals including pregnant women, if untreated. The mainstay of treatment is now endovascular embolization of the feeding artery which can alleviate the symptoms and prevent these complications. In this review, we describe the pathophysiology, methods of screening, diagnostic workup and treatment of these vascular lesions with a particular focus on the currently used embolization techniques and their outcomes.

Cross-sectional imaging of congenital pulmonary artery anomalies Abstract Congenital pulmonary artery (PA) anomalies comprise a rare and heterogeneous spectrum of disease, ranging from abnormal origins to complete atresia. They may present in early infancy or more insidiously in adulthood, often in association with congenital heart disease such as tetralogy of Fallot or other syndromes. In recent years, cross-sectional imaging, including computed tomography (CT) and magnetic resonance imaging (MRI), has become widely utilized for the noninvasive assessment of congenital PA diseases, supplementing echocardiography and at times supplanting invasive angiography. In this article, modern CT and MRI techniques for imaging congenital PA disorders are summarized. The key clinical features, cross-sectional imaging findings, and treatment options for the most commonly encountered entities are then reviewed. Emphasis is placed on the ever-growing role of cross-sectional imaging options in facilitating early and accurate diagnosis and tailored treatment.

Doppler estimates of pulmonary vascular resistance to phenotype pulmonary hypertension in heart failure Abstract An accurate distinction between isolated post-capillary pulmonary hypertension (Ipc-PH) and combined post- and pre-capillary pulmonary hypertension (Cpc-PH) is integral to therapy and prognosis in heart failure (HF). This study aimed to compare the ability of four previously validated Doppler estimates of pulmonary vascular resistance (PVRDoppler) to distinguish Ipc-PH from Cpc-PH in a well-defined HF population. Consecutive subjects referred for HF assessment underwent standard echocardiography immediately followed by right heart catheterization (RHC). Subjects with atrial fibrillation, acute coronary syndrome, significant valvular disease or poor image quality were excluded. PVRDoppler estimates were correlated with invasive PVR and agreement was studied using Bland–Altman analysis. Receiver operating characteristics analyses were performed to determine the ability of PVRDoppler methods to identify PVR > 3WU. 55 HF subjects (58 ± 16 years, 55% Ipc-PH) were analyzed. PVRDoppler estimates demonstrated weak to modest associations with invasive PVR. The Doppler method proposed by Abbas et al. demonstrated relatively strong discriminatory ability to distinguish Ipc-PH from Cpc-PH (AUC = 0.79; 95% CI 0.63–0.96; p = 0.001). However, Bland–Altman analysis revealed wide limits of agreement (bias = 0; SD = 1.83WU) and greater variability at higher mean PVR. Conclusions: PVRDoppler estimates demonstrate reasonable ability to distinguish Ipc-PH from Cpc-PH but may not be reliable independent PH distinguishers in HF.