A Murine Model of Pressure Overload-Induced Right Ventricular Hypertrophy and Failure by Pulmonary Trunk Banding.

Right ventricular (RV) failure caused by pressure overload is strongly associated with morbidity and mortality in a number of cardiovascular and pulmonary diseases. The pathogenesis of RV failure is complex and remains inadequately understood. To identify new therapeutic strategies for the treatment of RV failure, robust and reproducible animal models are essential. Models of pulmonary trunk banding (PTB) have gained popularity, as RV function can be assessed independently of changes in the pulmonary vasculature. In this paper, we present a murine model of RV pressure overload induced by PTB in 5-week-old mice. The model can be used to induce different degrees of RV pathology, ranging from mild RV hypertrophy to decompensated RV failure. Detailed protocols for intubation, PTB surgery, and phenotyping by echocardiography are included in the paper. Furthermore, instructions for customizing instruments for intubation and PTB surgery are given, enabling fast and inexpensive reproduction of the PTB model. Titanium ligating clips were used to constrict the pulmonary trunk, ensuring a highly reproducible and operator-independent degree of pulmonary trunk constriction. The severity of PTB was graded by using different inner ligating clip diameters (mild: 450 µm and severe: 250 µm). This resulted in RV pathology ranging from hypertrophy with preserved RV function to decompensated RV failure with reduced cardiac output and extracardiac manifestations. RV function was assessed by echocardiography at 1 week and 3 weeks after surgery. Examples of echocardiographic images and results are presented here. Furthermore, results from right heart catheterization and histological analyses of cardiac tissue are shown.

The value of right ventricular pulmonary artery coupling in determining the prognosis of patients with sepsis.

The outcomes of patients with sepsis are influenced by the contractile function of the right ventricle (RV), but the impact of cardiopulmonary interaction in ICU-mortality of sepsis patients remains unclear. This study aims to investigate the ICU-mortality impact of right ventricular-pulmonary artery (RV-PA) coupling in patients with sepsis. We employed echocardiography to assess patients with sepsis within the initial 24 h of their admission to the ICU. RV-PA coupling was evaluated using the tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP) ratio. A total of 92 subjects were enrolled, with 55 survivors and 37 non-survivors. TAPSE/PASP ratio assessed mortality with an area under the curve (AUC) of 0.766 (95% CI 0.670-0.862) and the optimal cutoff value was 0.495 mm/mmHg. We constructed a nomogram depicting the TAPSE/PASP in conjunction with IL-6 and Lac for the joint prediction of sepsis prognosis, and demonstrated the highest predictive capability (AUC = 0.878, 95% CI 0.809-0.948). In conclusion, the TAPSE/PASP ratio demonstrated prognostic value for ICU mortality in sepsis patients. The nomogram, which combines the TAPSE/PASP, IL-6, and LAC, demonstrated enhanced predictive efficacy for the prognosis of sepsis patients.

LncRNAH19 acts as a ceRNA of let-7 g to facilitate endothelial-to-mesenchymal transition in hypoxic pulmonary hypertension via regulating TGF-ß signalling pathway.

BACKGROUND: Hypoxic pulmonary hypertension (HPH) is a challenging lung arterial disorder with remarkably high incidence and mortality rates, and the efficiency of current HPH treatment strategies is unsatisfactory. Endothelial-to-mesenchymal transition (EndMT) in the pulmonary artery plays a crucial role in HPH. Previous studies have shown that lncRNA-H19 (H19) is involved in many cardiovascular diseases by regulating cell proliferation and differentiation but the role of H19 in EndMT in HPH has not been defined. METHODS: In this research, the expression of H19 was investigated in PAH human patients and rat models. Then, we established a hypoxia-induced HPH rat model to evaluate H19 function in HPH by Echocardiography and hemodynamic measurements. Moreover, luciferase reporter gene detection, and western blotting were used to explore the mechanism of H19. RESULTS: Here, we first found that the expression of H19 was significantly increased in the endodermis of pulmonary arteries and that H19 deficiency obviously ameliorated pulmonary vascular remodelling and right heart failure in HPH rats, and these effects were associated with inhibition of EndMT. Moreover, an analysis of luciferase activity indicated that microRNA-let-7 g (let-7 g) was a direct target of H19. H19 deficiency or let-7 g overexpression can markedly downregulate the expression of TGFßR1, a novel target gene of let-7 g. Furthermore, inhibition of TGFßR1 induced similar effects to H19 deficiency. CONCLUSIONS: In summary, our findings demonstrate that the H19/let-7 g/TGFßR1 axis is crucial in the pathogenesis of HPH by stimulating EndMT. Our study may provide new ideas for further research on HPH therapy in the near future.

Reduced dynamic changes in pulmonary artery compliance during isometric handgrip exercise in patients with heart failure.

Exercise intolerance is a debilitating symptom in heart failure (HF), adversely affecting both quality of life and long-term prognosis. Emerging evidence suggests that pulmonary artery (PA) compliance may be a contributing factor. This study aims to non-invasively assess PA compliance and its dynamic properties during isometric handgrip (HG) exercise in HF patients and healthy controls, using cardiovascular magnetic resonance (CMR). We prospectively enrolled 36 subjects, comprising 17 HF patients (NYHA class II and III) and 19 healthy controls. Participants performed an HG test, and we assessed changes in PA compliance and hemodynamic flow parameters using advanced CMR techniques. We also explored the relationship between CMR-derived PA compliance metrics and established clinical indicators, ensuring the validity of our findings through intra- and interobserver agreements. HF patients had significantly lower resting PA compliance compared to controls (28.9% vs. 50.1%, p < 0.01). During HG exercise, HF patients exhibited a dampened adaptability in PA compliance. Hemodynamic responses, including heart rate and blood pressure, were not significantly different between the groups. Further analyses revealed a significant correlation between changes in PA compliance and functional capacity, and an inverse relationship with NYHA class. Our study demonstrates a marked difference in PA vascular responses during HG exercise between HF patients and healthy controls. The compromised adaptability in PA compliance in HF patients is correlated with diminished functional capacity. These findings have significant clinical implications and may guide future interventional strategies in HF management.

Expiratory Venous Volume and Arterial Tortuosity are Associated with Disease Severity and Mortality Risk in Patients with COPD: Results from COSYCONET.

Purpose: The aim of this study was to evaluate the association between computed tomography (CT) quantitative pulmonary vessel morphology and lung function, disease severity, and mortality risk in patients with chronic obstructive pulmonary disease (COPD). Patients and Methods: Participants of the prospective nationwide COSYCONET cohort study with paired inspiratory-expiratory CT were included. Fully automatic software, developed in-house, segmented arterial and venous pulmonary vessels and quantified volume and tortuosity on inspiratory and expiratory scans. The association between vessel volume normalised to lung volume and tortuosity versus lung function (forced expiratory volume in 1 sec [FEV1]), air trapping (residual volume to total lung capacity ratio [RV/TLC]), transfer factor for carbon monoxide (TLCO), disease severity in terms of Global Initiative for Chronic Obstructive Lung Disease (GOLD) group D, and mortality were analysed by linear, logistic or Cox proportional hazard regression. Results: Complete data were available from 138 patients (39% female, mean age 65 years). FEV1, RV/TLC and TLCO, all as % predicted, were significantly (p < 0.05 each) associated with expiratory vessel characteristics, predominantly venous volume and arterial tortuosity. Associations with inspiratory vessel characteristics were absent or negligible. The patterns were similar for relationships between GOLD D and mortality with vessel characteristics. Expiratory venous volume was an independent predictor of mortality, in addition to FEV1. Conclusion: By using automated software in patients with COPD, clinically relevant information on pulmonary vasculature can be extracted from expiratory CT scans (although not inspiratory scans); in particular, expiratory pulmonary venous volume predicted mortality. Trial Registration: NCT01245933.

Pulmonary Vascular Responses to Chronic Intermittent Hypoxia in a Guinea Pig Model of Obstructive Sleep Apnea.

Experimental evidence suggests that chronic intermittent hypoxia (CIH), a major hallmark of obstructive sleep apnea (OSA), boosts carotid body (CB) responsiveness, thereby causing increased sympathetic activity, arterial and pulmonary hypertension, and cardiovascular disease. An enhanced circulatory chemoreflex, oxidative stress, and NO signaling appear to play important roles in these responses to CIH in rodents. Since the guinea pig has a hypofunctional CB (i.e., it is a natural CB knockout), in this study we used it as a model to investigate the CB dependence of the effects of CIH on pulmonary vascular responses, including those mediated by NO, by comparing them with those previously described in the rat. We have analyzed pulmonary artery pressure (PAP), the hypoxic pulmonary vasoconstriction (HPV) response, endothelial function both in vivo and in vitro, and vascular remodeling (intima-media thickness, collagen fiber content, and vessel lumen area). We demonstrate that 30 days of the exposure of guinea pigs to CIH (FiO2, 5% for 40 s, 30 cycles/h) induces pulmonary artery remodeling but does not alter endothelial function or the contractile response to phenylephrine (PE) in these arteries. In contrast, CIH exposure increased the systemic arterial pressure and enhanced the contractile response to PE while decreasing endothelium-dependent vasorelaxation to carbachol in the aorta without causing its remodeling. We conclude that since all of these effects are independent of CB sensitization, there must be other oxygen sensors, beyond the CB, with the capacity to alter the autonomic control of the heart and vascular function and structure in CIH.

Pulmonary Hypertension Induced by Right Pulmonary Artery Occlusion: Hemodynamic Consequences of Bmpr2 Mutation.

BACKGROUND: The primary genetic risk factor for heritable pulmonary arterial hypertension is the presence of monoallelic mutations in the BMPR2 gene. The incomplete penetrance of BMPR2 mutations implies that additional triggers are necessary for pulmonary arterial hypertension occurrence. Pulmonary artery stenosis directly raises pulmonary artery pressure, and the redirection of blood flow to unobstructed arteries leads to endothelial dysfunction and vascular remodeling. We hypothesized that right pulmonary artery occlusion (RPAO) triggers pulmonary hypertension (PH) in rats with Bmpr2 mutations. METHODS AND RESULTS: Male and female rats with a 71 bp monoallelic deletion in exon 1 of Bmpr2 and their wild-type siblings underwent acute and chronic RPAO. They were subjected to full high-fidelity hemodynamic characterization. We also examined how chronic RPAO can mimic the pulmonary gene expression pattern associated with installed PH in unobstructed territories. RPAO induced precapillary PH in male and female rats, both acutely and chronically. Bmpr2 mutant and male rats manifested more severe PH compared with their counterparts. Although wild-type rats adapted to RPAO, Bmpr2 mutant rats experienced heightened mortality. RPAO induced a decline in cardiac contractility index, particularly pronounced in male Bmpr2 rats. Chronic RPAO resulted in elevated pulmonary IL-6 (interleukin-6) expression and decreased Gdf2 expression (corrected P value<0.05 and log2 fold change>1). In this context, male rats expressed higher pulmonary levels of endothelin-1 and IL-6 than females. CONCLUSIONS: Our novel 2-hit rat model presents a promising avenue to explore the adaptation of the right ventricle and pulmonary vasculature to PH, shedding light on pertinent sex- and gene-related effects.

Total pulmonary arterial reconstruction in a patient with arterial tortuosity syndrome affecting the pulmonary artery: a case report and review of the literature.

BACKGROUND: Arterial tortuosity syndrome is a rare Autosomal recessive disease that leads to a loss of function of the connective tissues of the body, this happens due to a mutation in the solute carrier family 2 member 10 (SLC2A10) gene. ATS is more likely to occur in Large and medium-sized arteries including the aorta and pulmonary arteries. This syndrome causes the arteries to be elongated and tortuous, This tortuosity disturbs the blood circulation resulting in stenosis and lack of blood flow to organs and this chronic turbulent flow increases the risk of aneurysm development, dissection and ischemic events. CASE PRESENTATION: A 2 years old Arabian female child was diagnosed with ATS affecting the pulmonary arteries as a newborn, underwent a pulmonary arterial surgical reconstruction at the age of 2 years old due to the development of pulmonary artery stenosis with left pulmonary artery having a peak gradient of 73 mmHg with a peak velocity of 4.3 m/s and the right pulmonary artery having a peak gradient of 46 mmHg with a peak velocity of 3.4 m/s causing right ventricular hypertension. After surgical repair the left pulmonary artery has a peak pressure gradient of 20 mmHg, with the right pulmonary artery having a peak pressure gradient of 20 mmHg. CONCLUSION: ATS is a rare genetic condition that affects the great arteries especially the pulmonary arteries causing stenotic and tortuous vessels that may be central branches or distal peripheral branches that leads to severe right ventricular dysfunction and hypertension. We believe that surgical treatment provides the optimum outcomes when compared to transcather approaches especially when the peripheral arteries are involved. Some challenges and hiccups might occur, especially lung reperfusion injury that needs to be diagnosed and treated accordingly.

Antiplatelet and Antithrombotic Properties of Compound L-36, a 6H-1,3,4-Thiadiazine Derivative.

Compound L-36, a new derivative of 6H-1,3,4-thiadiazine, was studied in in vitro and in vivo experiments. This compound exhibits high antiplatelet and antithrombogenic activity. In in vitro experiments, compound L-36 by its antiplatelet activity (by IC50) was superior to acetylsalicylic acid by 9.4 times. In in vivo experiments, compound L-36 by its ED50 value was close to the comparison drug. On the model of pulmonary artery thrombosis, compound L-36 ensured better survival of experimental animals than acetylsalicylic acid. Morphological studies showed that compound L-36 effectively attenuated the thrombosis processes in the pulmonary tissue induced by intravenous injection of a thrombogenic mixture (epinephrine and collagen).

Pulmonary Artery Pressures and Mortality During Venoarterial ECMO: An ELSO Registry Analysis.

BACKGROUND: Systemic hemodynamics and specific ventilator settings have been shown to predict survival during venoarterial extracorporeal membrane oxygenation (ECMO). How the right heart (the right ventricle and pulmonary artery) affect survival during venoarterial ECMO is unknown. We aimed to identify the relationship between right heart function with mortality and the duration of ECMO support. METHODS: Cardiac ECMO runs in adults from the Extracorporeal Life Support Organization Registry between 2010 and 2022 were queried. Right heart function was quantified via pulmonary artery pulse pressure (PAPP) for pre-ECMO and on-ECMO periods. A multivariable model was adjusted for modified Society for Cardiovascular Angiography and Interventions stage, age, sex, and concurrent clinical data (ie, pulmonary vasodilators and systemic pulse pressure). The primary outcome was in-hospital mortality. RESULTS: A total of 4442 ECMO runs met inclusion criteria and had documentation of hemodynamic and illness severity variables. The mortality rate was 55%; nonsurvivors were more likely to be older, have a worse Society for Cardiovascular Angiography and Interventions stage, and have longer pre-ECMO endotracheal intubation times (P<0.05 for all) than survivors. Increasing PAPP from pre-ECMO to on-ECMO time (ΔPAPP) was associated with reduced mortality per 2 mm Hg increase (odds ratio, 0.98 [95% CI, 0.97-0.99]; P=0.002). Higher on-ECMO PAPP was associated with mortality reduction across quartiles with the greatest reduction in the third PAPP quartile (odds ratio, 0.75 [95% CI, 0.63-0.90]; P=0.002) and longer time on ECMO per 10 mm Hg (beta, 15 [95% CI, 7.7-21]; P<0.001). CONCLUSIONS: Early on-ECMO right heart function and interval improvement from pre-ECMO values were associated with mortality reduction during cardiac ECMO. Incorporation of right heart metrics into risk prediction models should be considered.

Anomalous origin of the right coronary artery from the pulmonary artery (ARCAPA): Echocardiographic diagnosis in a critically ill newborn.

ARCAPA echocardiographic diagnosis. A network of small multiple coronary vessels, a systo-diastolic jet of flow into the pulmonary artery and a retrograde inverted «blue¼ flow into the RCA are the key signs. CT-scan confirms the diagnosis .

Effect of caspase inhibitors on hemodynamics and inflammatory factors in ARDS model rats.

To study the effects of caspase inhibitors on hemodynamics and inflammatory factors in acute respiratory distress syndrome (ARDS) model rats. Sixty healthy male Wistar rats were randomly divided into three groups, namely, the control group, ARDS group and ARDS + Caspase inhibitor group, with 20 rats in each group. The control group was intraperitoneally injected with 2 mL/kg saline, and the ARDS model group was established by intraperitoneally injecting 4 mg/kg Lipopolysaccharide (LPS), ARDS + Caspase inhibitor group was adminstered 20 mg/kg caspase inhibitor after intraperitoneal LPS injection. Changes in pulmonary arterial pressure (PAP) and mean arterial pressure (MAP) at 6 and 12 h before and after administration were recorded. Moreover, arterial blood gas was evaluated with a blood gas analyzer and changes in the partial pressure of O2 (PaO2), partial pressure of CO2 (PaCO2), partial pressure of O2/fraction of inspired O2 (PaO2/FiO2) were evaluated. In addition, the lung wet/dry weight (W/D) ratio and inflammatory factor levels in lung tissue were determined. Finally, pathological sections were used to determine the pulmonary artery media thickness (MT), MT percentage (MT%), and the degree of muscle vascularization. The pulmonary arterial pressure of rats was determined at several time points. Compared with the control group, the model group had a significantly increased pulmonary arterial pressure at each time point (P < 0.01), and the mean arterial pressure significantly increased at 6 h (P < 0.05). Compared with that of rats in the model group, the pulmonary arterial pressure of rats in drug administration group was significantly reduced at each time point after administration (P < 0.01), and the mean arterial pressure was significantly reduced at 6 h (P < 0.05). The arterial blood gas analysis showed that compared with those in the control group, PaO2, PaCO2 and PaO2/FiO2 in the model group were significantly reduced (P < 0.01), and PaO2, PaCO2 and PaO2/FiO2 were significantly increased after caspase inhibitor treatment (P < 0.05 or 0.01). The levels of the inflammatory mediators tumor necrosis factor-alpha (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6) in the model group were significantly higher than those in the control group (P < 0.01), and they were significantly decreased after caspase inhibitor treatment (P < 0.01). In the model group, pulmonary artery MT, MT% and the degree of muscle vascularization were significantly increased (P < 0.05 or 0.01), and pulmonary artery MT and the degree of muscle vascularization were significantly reduced after caspase inhibitor treatment (P < 0.05 or 0.01). Apoptosis Repressor with a Caspase Recuitment Domain (ARC) can alleviate the occurrence and development of pulmonary hypertension (PH) by affecting hemodynamics and reducing inflammation.

Investigation into the role of H2-Ab1 in vascular remodeling in pulmonary arterial hypertension via Bioinformatics.

BACKGROUND: Pulmonary arterial hypertension (PAH) is a progressive disease of vascular remodeling characterized by persistent pulmonary arterial pressure elevation, which can lead to right heart failure and premature death. Given the complex pathogenesis and poor prognosis of PAH, the identification and investigation of biomarkers become increasingly critical for advancing further understanding of the disease. METHODS: PAH-related datasets, GSE49114, GSE180169 and GSE154959, were downloaded from the publicly available GEO database. By performing WGCNA on the GSE49114 dataset, a total of 906 PAH-related key module genes were screened out. By carrying out differential analysis on the GSE180169 dataset, a total of 576 differentially expressed genes were identified. Additionally, the GSE154959 single-cell sequencing dataset was also subjected to differential analysis, leading to the identification of 34 DEGs within endothelial cells. By taking intersection of the above three groups of DEGs, five PAH-related hub genes were screened out, namely Plvap, Cyp4b1, Foxf1, H2-Ab1, and H2-Eb1, among which H2-Ab1 was selected for subsequent experiments. RESULTS: A SuHx mouse model was prepared using the SU5416/hypoxia method, and the successful construction of the model was evaluated through Hematoxylin-Eosin staining, hemodynamic detection, fulton index, and Western Blot (WB). The results of WB and qRT-PCR demonstrated a significant upregulation of H2-Ab1 expression in SuHx mice. Consistent with the results of bioinformatics analysis, a time-dependent increase was observed in H2-Ab1 expression in hypoxia-treated mouse pulmonary artery endothelial cells (PAECs). To investigate whether H2-Ab1 affects the development and progression of PAH, we knocked down H2-Ab1 expression in PAECs, and found that its knockdown inhibited the viability, adhesion, migration, and angiogenesis, while concurrently promoted the apoptosis of PAECs. CONCLUSION: H2-Ab1 could regulate the proliferation, apoptosis, adhesion, migration, and angiogenesis of PAECs.

Right Ventricular-Pulmonary Arterial Coupling and Outcome in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Right ventricular-pulmonary artery coupling (RVPAC) refers to the relationship between right ventricular systolic force and afterload. The ratio of echocardiograph-derived tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP) has been proposed as a noninvasive measurement of RVPAC and reported as an independent prognostic parameter of heart failure. However, it has not been adequately in detail evaluated in heart failure with preserved ejection fraction (HFpEF). We hypothesized that RVPAC may be used and proposed as an expression of key risk factors in patients with HFpEF. METHODS: We retrospectively analyzed TAPSE/PASP of 648 HFpEF patients hospitalized in Chongqing Hospital of Traditional Chinese Medicine from January 1, 2016 to January 1, 2017. All eligible patients were followed up for 5 years. The correlation between TAPSE/SPAP index and clinical indicators and outcomes was evaluated. RESULTS: The final analysis included 414 patients. Nonsurvivors had significantly lower TAPSE, TAPSE/PASP and higher PASP compared with survivors (p < 0.0001). ROC curve analysis showed that the optimal cutoff of TAPSE, PASP, and RVPAC to predict all-cause death were 16.5 mm, 37.5 mmHg, and 0.45 mm/mmHg, respectively. In multivariate Cox regression analyses adjusted for gender showed a significant, independent association of the RVPAC with the composite endpoint of all-cause death or HF-related recurrent hospitalization (HR: 0.006; 95% CI 0.001-0.057, p < 0.001). CONCLUSIONS: RVPAC, defined by the ratio of TAPSE to PASP, is the expression of a key risk factor in HFpEF patients, which is independently associated with the composite endpoint of all-cause death or HF-related recurrent hospitalization.

[Expert consensus on the operating procedures for pulmonary angiography].

Pulmonary angiography is an important invasive diagnostic technique for pulmonary vascular diseases. With the development of pulmonary vascular interventions, pulmonary angiography has been applied more frequently. We focused on the history of pulmonary angiography, anatomy of pulmonary artery, the indications and contraindications of pulmonary angiography, preoperative preparation, operating procedures, the interpretation of pulmonary angiography results and the prevention and management of complications, with the aim of standardizing the operating procedures of pulmonary angiography and improving the diagnosis of pulmonary vascular diseases.Recommendation 1:Given the complexity of pulmonary artery anatomy, pulmonary angiography should be performed in a variety of positions to clearly visualise the morphology of pulmonary artery lesions.Recommendation 2:Pulmonary angiography, as an invasive vascular procedure, should only be performed after the indications have been clearly established, the risks and benefits have been weighed, and informed consent has been obtained.Recommendation 3:Secondary hypertonic or isotonic iodinated contrast agents with iodine concentrations>300 mg/ml are recommended for pulmonary angiography.Recommendation 4:Pulmonary angiography may be performed using the digital subtraction angiography (DSA) mode or cine radiography mode, depending on the patient's cooperation in breath-holding and the needs of the interventional procedure.Recommendation 5:Pulmonary Flow Grade is recommended to depict the blood flow status of pulmonary artery.Recommendation 6:Following pulmonary angiography, the vital signs, oxygenation status and the condition of the puncture site should be closely monitored.

Surgical Intervention for Giant Pulmonary Artery Aneurysm in Behcet Disease: A Case Report.

BACKGROUND Pulmonary artery aneurysm (PAA), defined as a pathologic dilatation of the PA greater than 1.5-fold the normal diameter, is a rare complication of Behçet disease. It is due to a weakening of the vessel wall for a great vessels' vasculitis, often asymptomatic and incidentally diagnosed on imaging studies. However, if ignored, it can lead to life-threatening complications such as rupture and massive hemoptysis. We report the case of a giant fast-growing PAA in a young patient with a history of Behçet disease in which an inadequate follow-up and poor patient information could had led to life-threatening complications. CASE REPORT A 37-year-old man with a history of Behçet disease presented to our Emergency Department with hemoptysis due to a right inferior lobar artery aneurysm measuring 52×33 mm. The aneurysm was detected years before, measuring 18 mm, but the patient and physicians missed the subsequent follow-up. After several attempts at embolization, the multidisciplinary board suggested to proceed with surgical intervention. Surgery was performed with an extracorporeal circulation system kept on stand-by due to the high hemorrhagic risk. By opening the fissure, the dilatation of the inferior lobar artery was clearly identified up to the origin of the middle lobar branch. Thus, a lower-middle bilobectomy was performed after the introduction of a suction cannula in the aneurysm, which facilitated its emptying and the subsequent maneuvers. CONCLUSIONS PAA is a rare disease, generally treated with medical therapy or interventional procedures. However, giant and fast-growing aneurysms are more likely to entail complications and often required immediate treatment. In this case, primary surgical intervention with a pulmonary bilobectomy appeared mandatory to avoid life-threatening events.