Left Main Pulmonary Artery Research Articles

Association between echocardiographic parameters and abnormal spirometry among chronic heart failure patients

Abstract Background A significant proportion (10-40%) of heart failure (HF) patients have concomitant pulmonary disease which have negative effects on cardiovascular outcome of patients. Because of the similarities in symptoms between HF and pulmonary disease, the prevalence of concomitant pulmonary disease may be underestimated. Early detection manage accordingly may improve outcomes of HF patients. We aimed to study clinical and echocardiographic parameters identifying HF patients with concomitant pulmonary disease. Methods This cross-sectional study included adults (age≥18 years) who were diagnosed with HF. The echocardiogram, arterial blood gas and pulmonary function test (PFT) were performed. The patients were classified into normal and abnormal (obstructive and restrictive) PFT patterns. The primary outcome was the association between echocardiographic parameters and abnormal PFT. The receiver operating characteristic (ROC) curve was performed to evaluate diagnostic performance of echocardiographic parameter in detecting abnormal PFT. Results A total of 57 patients was enrolled, of which 32 patients (56.14%) had normal PFT, 14 patients (24.56%) had obstructive PFT, and 11 patients (19.30%) had restrictive PFT. The clinical characteristics were not different between groups. ROC curve demonstrated that only left atrial volume index (LAVI) and main pulmonary artery (MPA) diameter had significant diagnostic accuracy to predict abnormal PFT with AUC of 0.72 (95%CI 0.57-0.87) and 0.66 (95%CI 0.51-0.80) respectively. Using combination of LAVI (cutoff 40mm2/m2) and MPA diameter (cutoff 22.0 mm) had a sensitivity of 95.7% (95%CI 78.05-99.89%) and specificity of 41.94% (95%CI 24.55-60.92%) in detection patients with abnormal PFT. Conclusion Almost half of HF had concomitant abnormal PFT. The combination of LAVI and MPA diameter can identify patients with abnormal PFT with high negative predictive value and should be considered as screening parameters in HF patients.

Stapler-induced vascular injury during uniportal VATS lobectomy: lessons learned from a rare complication case

BackgroundDue to advances in video-assisted thoracic surgery (VATS), the majority of lung resections can be performed safely via VATS with low morbidity and mortality. However, pulmonary artery (PA) bleeding often requires emergency conversion to thoracotomy, potentially leading to a life-threatening situation. We report a case of pulmonary artery injury caused by an unexpected stapler-tissue interaction during uniportal VATS lobectomy, highlighting the importance of recognizing and managing such rare complications to improve patient outcomes.Case presentationA 63-year-old man underwent uniportal VATS left upper lobectomy for a suspected primary lung cancer. During the procedure, unexpected bleeding occurred from the third branch of the pulmonary artery (A3) after withdrawal of an unfired stapler. The protruding staple of the A3 stump was inadvertently hooked and stretched by the groove of the staple anvil. Although the bleeding was controlled by compression with the lung, the injured A3 stump required repair. Due to the extensive intimal injury near the central part of the left main pulmonary artery and the potential risk of fatal postoperative complications, we converted to open thoracotomy for definitive vascular repair by suturing. The patient had no postoperative complications and was discharged on postoperative day 8.ConclusionsThis case report provides valuable lessons regarding the rare stapler-related vascular injury during uniportal VATS lobectomy. It is important to note that even during non-vascular dissection, unexpected stapler-tissue interactions can lead to bleeding. To prevent the vessel stump entanglement with stapler components, maintaining separation between the stapler and staple stumps is crucial. In uniportal VATS, manipulation during stapler insertion is one of the most challenging phases for instrument interference, requiring increased caution to prevent complications such as the vascular injury described in this case. Thorough preoperative planning, specific intraoperative precautions, and adapted safety protocols that address the limitations of uniportal VATS are essential for effective management of potential complications. Although techniques for thoracoscopic vascular control exist, they are not always feasible and conversion to open thoracotomy should be considered when necessary to ensure patient safety.

Quantitative evaluation of pulmonary hypertension using 4D flow MRI: A retrospective study

BackgroundPulmonary hypertension (PH) is a severe vascular disorder that may affect 50 % of patients with heart failure. Currently, right-sided heart catheterization is required to definitively diagnose PH. However, this method is invasive and thus may not be appropriate for repeated, long-term monitoring of PH patients. This retrospective study's aim was to evaluate whether 4D flow magnetic resonance imaging (MRI) can be used to quantitively measure flow parameters to identify patients with PH. MethodsThe study cohort included 97 patients recruited from a single institution and divided into three groups based on echocardiographic estimate of pulmonary artery systolic pressure (PASP): normal group with PASP<36 mmHg, borderline PH group with PASP of 37–50 mmHg, and PH group with PASP>50 mmHg. 4D flow MRI was used to quantitively assess blood flow and velocity, regurgitation, wall shear stress (WSS) and kinetic energy in the pulmonary artery trunk, right main pulmonary artery, and left pulmonary artery. Two experienced radiologists independently analyzed the MR images, blinded to clinical details. ResultsWe found a significant difference in WSS in the pulmonary artery trunk, right main pulmonary artery and left main pulmonary artery among the three patient groups. We also found significant differences in the kinetic energy and average through velocity in the pulmonary artery trunk and right main pulmonary artery, and significant differences in the flow rate in the right main pulmonary artery. ConclusionThese data suggest that 4D flow MRI can quantitate pulmonary artery flow parameters and distinguish between patients with and without PH.

Chronic left pulmonary artery occlusion caused by a distal aortic arch aneurysm: Simultaneous Frozen Elephant Trunk and left sided pulmonary endarterectomy after livesaving TEVAR for aortic rupture

We present a case of a 62-year-old male patient with chronic distal aortic arch aneurysm causing recurrent nerve palsy and prolonged total occlusion of the left main pulmonary artery (PA). During diagnostic work up, the aneurysm ruptured requiring cardio-pulmonary resuscitation (CPR) and emergency retrograde stenting. After circulatory stabilization the patient was treated with controlled hypothermia for 24 h, and successive extubation without neurological deficit.Postinterventional imaging revealed a reversed perfusion of the aneurysmal sac through the PA, prompting open surgical treatment. Surgery consisted of reconstruction of the left PA by pulmonary endarterectomy (PEA), xenopericardial patchplasty of the left PA and frozen elephant trunk (FET) repair after removal of the bare springs of the previously inserted Gore Tag stent graft. Pre-discharge computed tomography angiography (CTA) demonstrated a fully recanalized left PA system and a completely excluded aneurysm. At ten-year follow-up the patient presented physically unimpaired (NYHA I). CTA confirmed a fully intact thoracic aorta and improved pulmonary function despite persisting left recurrent nerve palsy.

The accuracy of the Hounsfield unit in pulmonary embolism diagnostics.

Pulmonary embolism (PE) is a vascular disease that is most frequently diagnosed using the radiological imaging technique computed tomography pulmonary angiography (CTPA). In this study, we aimed to demonstrate the diagnostic accuracy of the Hounsfield unit (HU) for PE based on the hypothesis that acute thrombosis causes an increase in HU value on CT. This research was a single-center, retrospective study. Patients presenting to the emergency department diagnosed with PE on CTPA were enrolled as the study group. Patients admitted to the same emergency department who were not diagnosed with PE and had noncontrast CT scans were included as the control group. A receiver operating curve was produced to determine the diagnostic accuracy of HU values in predicting PE. The study population (n=74) consisted of a study group (n=46) and a control group (n=28). The sensitivity and specificity of the HU value for predicting PE on thoracic CT were as follows: for the right main pulmonary artery, 61.5% and 96.4% at a value of 54.8 (area under the curve [AUC], 0.690); for the left main pulmonary artery, 65.0% and 96.4% at a value of 55.9 (AUC, 0.736); for the right interlobar artery, 44.4% and 96.4% at a value of 62.7 (AUC, 0.615); and for the left interlobar artery, 60.0% and 92.9% at a value of 56.7 (AUC, 0.736). HU may exhibit high diagnostic specificity on CT for thrombi up to the interlobar level. An HU value exceeding 54.8 up to the interlobar level may raise suspicion of the presence of PE.

Clinical Presentation and Therapy of Tetralogy of Fallot and Double-Outlet Right Ventricle.

Tetralogy of Fallot (TOF) is the most common cyanotic heart defect. TOF consists of the combination of four anomalies (Fig. 35.1): (1) a large malalignment ventricular septal defect, (2) an obstruction of the right ventricular outflow tract (usually infundibular and valvular pulmonary stenosis with a small pulmonary valve annulus and supravalvular stenosis, (3) an aorta that "overrides" the ventricular septal defect, and (4) right ventricular hypertrophy. TOF represents 4-8% of congenital heart defects. Specific variations of TOF include all forms of pulmonary atresia with VSD and absent pulmonary valve syndrome. In addition, the left and right main pulmonary arteries may be stenotic or hypoplastic. In these cases, there may be major aortopulmonary collateral arteries (MAPCAs) which are vessels arising from the aorta or the subclavian arteries that supply segments of the pulmonary arterial tree. Additional variations include an ASD (Pentalogy of Fallot), a right aortic arch, and coronary abnormalities.

Abstract 13091: Chronic Thromboembolic Pulmonary Hypertension Associated With Prolonged Use of Combined Oral Contraceptives in a 27-Year-Old Woman: A Successful Case of Pulmonary Endarterectomy

Introduction: Chronic thromboembolic pulmonary hypertension (CTEPH) is associated with venous thromboembolism (VTE); however, in half of the cases, no prior deep vein thrombosis is ever found. The use of combined oral contraceptives (COCs) is a known risk factor for VTE. We present the case of a young woman with CTEPH in whom timely diagnosis and intervention prevented irreversible pulmonary hypertension (PH). Case Presentation: A 27-year-old woman with 10-year use of COCs presented with progressive dyspnea for 3 weeks. The ECG showed right ventricular systolic overload and right atrial enlargement. Laboratory tests showed elevated pro-BNP and D-dimer. TTE showed right atrium and right ventricle (RV) enlargement and elevated right ventricular systolic pressure (RVSP) of 83 mmHg. The ventilation/perfusion scintigraphy showed mismatched segmental perfusion defects in both lung fields with greater involvement of the left lung, and oral anticoagulation was started. Lower extremity venous ultrasound and hypercoagulability studies were normal. CTPA revealed filling defects in the left main pulmonary artery and bilateral segmental branches. After 3 months of anticoagulation, she persisted in NYHA class III, and right heart catheterization showed mean PAP of 38 mmHg, PCWP of 8 mmHg, and PVR of 9 WU, confirming CTEPH. Due to unavailability in Peru, she was referred to a US center for pulmonary endarterectomy (PEA). After a successful intervention, she improved clinically with a reduction in RVSP to 34 mmHg. This case highlights the importance of rapid intervention in CTEPH even in situations where optimal treatment is not readily available. Conclusion: CTEPH may be associated with the prolonged use of COCs in young women. Timely intervention can reverse PH and prevent RV remodeling. Unfortunately, Peru does not have a PEA center and not every case will undergo treatment. We call for the training of local surgeons to ensure fair and equitable access for the population.

Frequency of various cardiac complications in children with repaired tetralogy of Fallot identified by computer tomography

BACKGROUND: Tetralogy of Fallot represents 710% of all cases of congenital heart disease, as it occurs in approximately 0.5 per 1,000 live births and is the second most common form of complex congenital heart disease. Advances in diagnosis, surgical techniques, and postoperative treatment have led to an increasing number of patients reaching adulthood, with a dramatic increase in the survival rate to almost 90% at 30 years, thereby creating a need for long-term monitoring of certain anatomic parameters to identify complications in a timely manner. This study aimed to investigate the frequency of computed tomography detected complications after radical correction of Tetralogy of Fallot in pediatric patients.&#x0D; AIM: to identify markers between the most frequency computed tomography detected complications after repair of Tetralogy of Fallot in pediatric patients.&#x0D; MATERIALS AND METHODS: A retrospective analysis was conducted on 613 patients with Tetralogy of Fallot from October 2011 to June 2020. The study included a total of 116 patients (69 men and 47 women) who experienced complications after a repair of Tetralogy of Fallot, as identified by computed tomography. At the time of repair of Tetralogy of Fallot, the patients average age ranged from 10 to 36 months (mean: 12 months), average body weight was 21 kg, average height was 105.4 cm, and average body surface area was 0.74 m2. The patients median age at the time of the computed tomography examination was 17.5 years (age range: 736 years).&#x0D; RESULTS: Among the 116 patients who exhibited complications after an repair of Tetralogy of Fallot, 49 had a pulmonary artery stenosis, 92 had a pulmonary artery branch stenosis (56 of them of the left main pulmonary artery branch, and 36 of them of the right main pulmonary artery branch), 8 had a right ventricular outflow tract stenosis, 32 had a ventricular septal defect, 1 had a shunt thrombosis, 12 had a postoperative deformation of the pulmonary artery, 10 exhibited a marked right ventricular dilatation, 2 had an right ventricular outflow tract aneurysm, and 6 suffered from conduit calcification and stenosis. Moreover, patients with left main pulmonary artery branch stenosis had a 6.5 times greater chance of developing an right main pulmonary artery branch stenosis in (p 0.001).&#x0D; CONCLUSION: The most frequently computed tomography detected complications after a repair of Tetralogy of Fallot were pulmonary artery stenosis and pulmonary artery branch stenosis. Patients with pulmonary artery stenosis and pulmonary artery branch stenosis exhibit no significant differences in terms of age, anthropometric parameters (height, weight, and body surface area), and gender distribution in the presence or absence of different stenosis types (pulmonary artery, right main pulmonary artery branch, or left main pulmonary artery branch). However, an right main pulmonary artery branch stenosis increases the chances of developing an left main pulmonary artery branch stenosis.

腹臥位から仰臥位へ体位交換時に肺血栓塞栓症を発症した重症COVID–19肺炎の2例(Two cases of pulmonary embolism after position change from prone position during mechanical ventilation due to severe COVID–19 pneumonia)

COVID–19肺炎では腹臥位呼吸療法の有効性が注目されている。今回，腹臥位から仰臥位への体位交換時に発症した肺血栓塞栓症を2例経験したので報告する。1例目は59歳の男性，発症11日目に人工呼吸を開始し，15日目から腹臥位呼吸療法を開始した。17日目に仰臥位へ体位交換した30分後より，SpO2が94%から85%へと低下し，心拍数も90bpmから120bpmへ上昇した。D–ダイマーが9.2μg/mLから22.5μg/mLへ上昇していたため，肺血栓塞栓症を疑い，造影CTで左肺動脈血栓が判明した。2例目は46歳の男性，発症13日目で人工呼吸を開始し，同日腹臥位呼吸療法を開始した。14日目に仰臥位へ体位交換した10分後より血圧低下，12分後からSpO2が97%から84%へと低下した。D–ダイマーが5.6μg/mLから48.1μg/mLへ上昇していたことと，心臓超音波検査で右心負荷所見がみられたことから肺血栓塞栓症を疑い，造影CTで左内頸静脈血栓と右肺動脈血栓が判明した。今回の2症例は，いずれも腹臥位から仰臥位に体位交換した際に肺血栓塞栓症を発症しており，いずれも中心静脈カテーテル挿入側の内頸静脈に血栓を認めた。長時間の腹臥位から仰臥位への体位交換は，内頸静脈血栓から肺血栓塞栓症を発症させる可能性が示唆され，バイタルサインに留意して行うことが望ましい。 The prone position during mechanical ventilation has been reported to be effective in respiratory failure caused by COVID–19 pneumonia. We report two cases of pulmonary thromboembolism that may have occurred during return to the supine position. A 59–year–old man, with COVID–19 pneumonia, was put on mechanical ventilation in supine position from day 11 to day 15, and prone position from day 15 to day 17. Thirty minutes after returning to the supine position on day 17, he developed hypoxemia and tachycardia. Pulmonary thromboembolism was suspected based upon elevated D–dimer levels. Echo venogram of the right internal jugular vein showed thrombi, and contrast–enhanced computed tomography (CECT) showed thrombi in the left pulmonary artery. A 46–year–old man, with COVID–19 pneumonia, was put on mechanical ventilation in prone position from day 13 to day 14. On day 14, when he was returned to the supine position, he developed hypotension after 10 minutes, and hypoxemia after 12 minutes. CECT showed thrombi in the left internal jugular vein and right pulmonary artery. During mechanical ventilation, a change to the supine position after prolonged prone position may cause pulmonary thromboembolism from thrombi in the internal jugular vein, and should be performed with attention to vital signs. 腹臥位呼吸療法は，acute respiratory distress syndrome（ARDS）の死亡率を低下させる可能性があり 1，COVID–19肺炎にもしばしば実施される。当院でも，集中治療管理を要するCOVID–19肺炎患者に対し，16時から翌日10時の18時間を腹臥位，残りの6時間を仰臥位とする腹臥位呼吸療法を施行した。腹臥位呼吸療法での合併症として，気管チューブ閉塞，事故抜管，静脈路の事故抜去，褥瘡，視力障害，腕神経叢損傷などが報告されている 2。今回，腹臥位から仰臥位への体位交換を契機に発症した肺血栓塞栓症（pulmonary embolism: PE）を2例経験したので報告する。 なお，本症例の報告は倫理委員会の承諾は不要であり，個人情報保護法に基づいて匿名化がなされ，患者・家族の同意を得ている。 患 者：59歳の男性 既往歴：痛風，脂質異常症 現病歴：発熱・頭痛で発症し，同日SARS–CoV–2 PCR陽性と判明した。発症5日目に酸素化不良のため，当院に入院となった。11日目に呼吸状態悪化のため気管挿管し，人工呼吸管理となった。 入院後経過：気管挿管後より，深部静脈血栓症（deep vein venous thrombosis: DVT）予防を目的として，ヘパリンカルシウム5,000単位の皮下注射を1日2回開始した。発症13日目に撮像した体幹部造影CTでは，PE，DVTともに指摘されなかったが，14日目にD–ダイマーが9.8µg/mLと上昇した。超音波検査で，中心静脈カテーテル挿入側である右内頸静脈に血栓を認め（Fig. 1a），リバーロキサバン15mg内服を開始した。また，13日目に撮像したCTでは背側の無気肺が著明であり，人工呼吸器関連肺炎も併発したため，背面開放と体位ドレナージを目的とし，15日目より腹臥位呼吸療法を開始した。17日目に，腹臥位から仰臥位に体位交換した30分後より，SpO2が94%から85%へと低下し，心拍数も90bpmから120bpmへ上昇した（Fig. 2）。 Case 1: Jugular vein echo (a). major and minor axis image showing right internal jugular vein (white arrow). Chest computed tomography (b). Axial view showing left main pulmonary artery thrombus (white triangle). Case 1: Course at onset of pulmonary embolism. ベッドサイドで可能な検査や理学所見では，気胸や痰による閉塞性無気肺を認めなかった。超音波検査では右心拡大を認めなかったが，依然として右内頸静脈に血栓が存在していた。両側大腿静脈，膝窩静脈には，血栓はみられなかった。右内頸静脈血栓があること，D–ダイマーが22.5µg/mLと上昇（前日9.2µg/mL）していること，また長時間の腹臥位から体位交換をした際に起きた酸素化低下と頻脈であることから，PEを強く疑った。既にリバーロキサバン内服が行われていたが，治療量でなかったため30mgに増量し，翌日待機的に造影CTを施行した。造影CTでは，左主肺動脈に血栓塞栓症がみられた（Fig. 1b）。以上の所見より，腹臥位から仰臥位への体位交換を契機に発症したPEと診断した。 その後，COVID–19肺炎後器質化肺炎に対して，プレドニゾロン60mg/day（1mg/kg）を開始した。発症25日目に38度台の発熱があり，膿性痰が出現したため，人工呼吸器関連肺炎としてピペラシリン・タゾバクタム13.5ｇ/日を投与開始した。その後のCTで，左肺に多発空洞影を認め，肺化膿症と診断した。抗菌薬治療を60日間継続した後，発症93日目に，リハビリテーション目的に転院となった。 患 者：49歳の男性 既往歴：慢性中耳炎 現病歴：咽頭痛・発熱で発症し，翌日SARS–CoV–2 PCR陽性と判明した。呼吸困難感が出現したため，発症11日目に前医入院となった。呼吸状態悪化のため翌日当院に転院となり，13日目に気管挿管を施行し，人工呼吸管理を開始した。 入院後経過：気管挿管後より，DVT予防を目的として，ヘパリンカルシウム5,000単位の皮下注射を1日2回開始した。気管挿管後も酸素化が改善しなかったため，同日夕方より腹臥位呼吸療法を開始した。翌日，腹臥位から仰臥位に体位交換した10分後から，徐々に血圧が低下し，SpO2も低下した（Fig. 3）。 Case 2: Course at onset of pulmonary embolism. ベッドサイドで可能な検査や理学所見では，気胸や痰による閉塞性無気肺を認めなかった。超音波検査では，両側大腿静脈，膝窩静脈には血栓を認めなかったが，左内頸静脈の中心静脈カテーテル周囲に血栓を認め，右心拡大も認めた。左内頸静脈血栓があること，D–ダイマーが48.1µg/mLと上昇（前日5.6µg/mL）していること，右心負荷所見があり，長時間の腹臥位から体位交換をした際に起きた血圧低下，酸素化低下であることから，PEを強く疑った。APTTの目標を50secとしてヘパリンナトリウム14,000U/dayの持続静脈注射を開始し，同日に造影CTを施行した。造影CTでは左内頸静脈（下顎角から胸鎖関節付近の鎖骨下静脈合流部），および右肺動脈に血栓を認めた（Fig. 4a, b）。 Case 2: Chest computed tomography. Axial view showing right pulmonary artery thrombus in the middle lobe (a. white triangle). Axial view showing left internal jugular vein thrombus (b. white arrow). 以上の所見より，腹臥位から仰臥位へ体位交換した際に発症したPEと診断した。発症第15日目に人工呼吸器関連肺炎を発症したため，セフェピム3g/日を投与開始した。16日目に，P/F ratioが191から289へ改善し，18日目に気管チューブを抜去した。また，19日目にヘパリンからリバーロキサバン30mg/dayへ変更し，22日目に前医に再転院となった。 PEの塞栓源は，約90%が下肢あるいは骨盤内の静脈とされている。しかし，2例とも内頸静脈に血栓があり，超音波検査と造影CTで，両下肢静脈内に明らかな血栓はみられなかった。このことから，内頸静脈血栓からの塞栓子が原因で，PEを発症したと考えられる。集中治療を行う場合，内頸静脈への中心静脈カテーテル留置を行う機会が多いが，中心静脈カテーテルの挿入は内頸静脈血栓形成のリスクとして知られている 3。また，2例ともヘパリンの予防投与を行っていたが，中心静脈カテーテル挿入側の内頸静脈に血栓を認めた。COVID–19では，血管内皮細胞にもSARS–CoV–2感染が成立する。ウイルス感染により障害された血管内皮細胞からの凝固第VIII因子とvon Willebrand factorの放出や，サイトカインストームが血栓傾向の誘引となり，深部静脈血栓症の発症率が上昇するとされている 4。 なお，今回の2症例目では，中心静脈カテーテルを挿入した同日16時ごろから翌日10時ごろまで腹臥位呼吸療法を行い，仰臥位に体位交換をした際にPEを生じている。中心静脈カテーテル挿入時の超音波検査では血栓を認めておらず，腹臥位呼吸療法を行っている18時間の間に，血栓が形成された可能性が高い。鎖骨による鎖骨下静脈合流部への圧迫で内頸静脈の血流うっ滞が生じ，内頸静脈血栓の形成に腹臥位が寄与していた可能性が考えられる。1例目においても，長時間の腹臥位が，既存の内頸静脈血栓の伸展を助長した可能性がある。このような血栓形成のリスクが重なり，ヘパリン予防投与を行っていたにもかかわらず血栓が形成されたと考えられる。 DVTは，通常発生部位から中枢へ成長する過程で，血栓中枢端や伸展血栓が遊離，もしくは血栓の静脈壁接着面が剥離して塞栓子となる。関節周囲や下腿筋ポンプ内のような特殊な状況では，起立，歩行などの際に下肢の筋肉が収縮し，伸展血栓が容易に塞栓化しやすいとされている 5。腹臥位呼吸療法において，腹臥位から仰臥位へ体位交換したことを契機としてPEを発症したという報告は，我々の渉猟する限りみられなかったが，脊椎手術では数例報告されている 6, 7。腹臥位中は，鎖骨による圧迫や胸腔内圧上昇に伴い，内頸静脈や下大静脈のうっ滞が起こることが示唆されている。腹臥位から仰臥位への体位交換で，これらが解除されることにより，血行動態が一時的に変化しうる。それにより，体位交換という受動的な運動であっても，長時間の腹臥位の間に伸展，形成された内頸静脈血栓が遊離した可能性が考えられる。 腹臥位から仰臥位に体位交換した際の酸素化低下はしばしば経験され，原病が重篤，あるいは背側無気肺が著明である場合は，対症療法を行うのみで見過ごされてしまう可能性もある。しかし，今回1例目は頻脈，2例目では血圧低下と，SpO2の低下以外にもバイタルサインの変化を認めていた。COVID–19の血栓症発症リスクが高いことも踏まえ 8, 9，PEを鑑別にあげて対応し，治療介入することができた。さらに2例目は，1例目の経験から，仰臥位への体位交換が内頸静脈血栓を塞栓子としたPE発症の契機となる可能性があることを認識していた。そのため，ベッドサイドでの超音波検査で，両側大腿静脈に加え内頸静脈も観察を行い，内頸静脈血栓を認知することができ，PEを鑑別疾患の上位に挙げることができた。なお，両症例ともPE発症日の採血でD–ダイマーの上昇がみられていた。腹臥位呼吸療法施行中のD–ダイマー上昇は，血栓形成もしくは伸展を示唆している可能性があり，仰臥位に復帰した際にバイタルサイン変動がみられた場合には，PEの発症を疑う必要があると考える。なお，ARDS患者の腹臥位では健常人と異なり，換気血流比不均等の改善による右心負荷の軽減や，左心前負荷増大により，心拍出量が増加する 10。仰臥位への体位交換時には，これらの血行動態の変化は速やかに元に戻り，心拍出量は低下する。これは，PEを発症した際の重症度を高める可能性がある。 当院では，腹臥位からの体位交換時はSpO2，心電図，end–tidal CO2などの観血的動脈圧以外の一部モニターを外していた。同様にモニターを外しており初期症状であるバイタルサインの変化を察知できずに 11，心停止まで至った脊椎手術症例の報告もある 6。今回2例とも，モニターは仰臥位復帰後早急に再装着され，バイタルサインの変化に早期に気づくことができた。モニター未装着となる時間を短縮することが，早期にPEの兆候を察知するために重要である。なお，PE発症時にSpO2低下はよくみられるが，より劇的な症例では急激にend–tidal CO2が低下することが知られており，脊椎手術中end–tidal CO2低下がPE発症覚知の一助となった報告もある 12。当院では腹臥位から仰臥位への体位交換時，end–tidal CO2モニターを外していることがほとんどであった。end–tidal CO2モニターは，頭側で回路混線せずに装着したまま安全に体位交換できるため，今後の腹臥位療法では，装着を継続して体位交換することも，検討の余地がある。 腹臥位呼吸療法時は，内頸静脈還流のうっ滞などにより形成・伸展した内頸静脈血栓が，仰臥位への体位交換で遊離しPEを発症する恐れがあるため，注意して体位交換を行う必要がある。また，腹臥位からの体位復帰時に生じる循環虚脱や肺酸素化能の低下にはPEが関与している可能性があり，これらのバイタルサインの変化を早期に察知するために，装着可能なモニターはできる限り装着を継続し，困難な場合にもモニター未装着時間を可能な限り短縮して迅速な体位交換を行うことが望ましい。 著者全員に本論文に関する利益相反はない。

Assessment of Utility of Computed Tomography Pulmonary Angiography in Pulmonary Embolism

Background: Among all the available diagnostic tools, computed tomography (CT) is the preferred diagnostic tool for clinically suspected pulmonary embolism (PE) cases. Further, with the development of multi–detector row CT (MDCT) technology, previous limitations of CT have been overcome effectively. For patients with clinical suspicion of PE, MDCT pulmonary angiography has become the first line of modality for the diagnosis. Aims and Objectives: To evaluate various common observations of CT pulmonary angiography (CTPA) in suspected cases of PE that could accurately determine the choice of management. Materials and Methods: Fifty patients with clinically suspected PE referred to the department of Radiodiagnosis for CTPA from various departments were studied in the cross-sectional study. CT images were obtained with a SIEMENS 64-slice multi-detector CT scanner (somatom definition AS). Images were reconstructed into 3D, axial, coronal, sagittal maximum intensity projection sections, and volume rendering techniques. The axial as well as reformatted coronal and sagittal images were evaluated. Results: The incidence of PE was 52%. The incidence of PE was highest in patients older than 60 years (30.8%) and males (30.3%; p=0.662). The most common symptoms evoking a suspicion of pulmonary embolism were dyspnea (69.2%), followed by chest pain (15.4%), cough (11.5%), and hemoptysis (3.8%). Out of 26 patients who had PE, 61.5% had right ventricular enlargement. DVT (23.1%) was the most common past history. The majority of the patients had thrombus in the right main pulmonary artery (21.1 %), followed by the left main pulmonary artery (19.3 %). Conclusion: In clinically suspected cases of PE, MDCT pulmonary angiography was a useful diagnostic tool. CTPA is the modality of choice for its rapid, minimally invasive, and well-tolerated nature.

Demarcated by bronchial or vascular landmarks? a study on the lower borders of the lower paratracheal lymph nodes

IntroductionThe lower rim of the azygous arch and the upper rim of the left main pulmonary artery are used as the lower borders of the lower paratracheal lymph nodes (LNs) in the IASLC map. However, there is some confusion about it. Our aim was to investigate the best landmarks as the boundaries to stage N more accurately for lung cancer.Material and methodsOne hundred patients with benign lung diseases, fifty with lung cancer diagnosed by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), and thirteen with right metastatic LNs confirmed by surgery were included. The lymph nodes (including W1, W3, W5, 10R below W5, W4, W6) were classified with Wang's and IASLC map concurrently, and the different outcomes of N stage were compared.ResultsThe azygous arch and the left main pulmonary artery varied in relation to the airway, causing the following changes of classification, 9.4% benign LNs of W1 and 38.6% of W5 were down-regulated as IASLC-10R, 9.5% of 10R below W5 were up-regulated as IASLC-4R, 51.4% of W4 and 94% of W6 were down-regulated as IASLC-10L. In 50 patients diagnosed by EBUS-TBNA, the concordance between the two maps was 0.768 for the right 92 LNs, while it was 0.374 for the left 46 nodes. If based on the location of azygous arches, postoperative stages might be changed in 2 surgery patients.ConclusionsThe locations of the lower vascular boundaries of IASCL-4 were varied. The bronchial landmarks of the proximal right and left main bronchus might be used as such borders.

526 ALAGILLE SYNDROME, A CASE REPORT

Abstract Alagille syndrome (AGS) is a dominantly inherited multisystem disorder caused by heterozygous mutations of genes that are components of the Notch signaling pathway. The main clinical manifestations of AGS are intrahepatic bile duct paucity, congenital heart defects involving primarily the pulmonary arteries, butterfly vertebrae, anterior chamber defects of the eye and facial dysmorphism. A male patient of 39 years old came to our observation due to the worsening of dyspnea, cyanosis, dizziness, heartbeat and asthenia for about two years. His cardiological history includes percutaneous pulmonary artery angioplasty in both left and right main pulmonary artery in 1994. In 2012, finding of pulmonary hypertension and diagnosis of Alagille syndrome confirmed by genetic analysis (JAG1 gene), and vasoreactivity testing of the pulmonary circulation was positive. Intrastent restenosis of the right lobar pulmonary artery treated with POBA in 2016. Patient therapy includes, diltiazem 60 mg OD, macitentan 10 mg OD, sildenafil 40 mg TID. Echocardiogram showed: preserved global and segmental systolic function. Minimal mitral valve insufficiency. Dilated right ventricle (RV / LV&amp;gt; 1), ipokinetic. Right atrium of increased size. Mild tricuspid valve insufficiency (VD-AD 20 mmHg). reduced systolic flow acceleration time (80 msec). Inferior vena cava of normal caliber with preserved inspiratory collapse. Indirect signs of pulmonary hypertension. The six minutes walking test showed severe desaturation after only one hundred meters. Right catheterization showed severe pulmonary hypertension (PAPm 63 mmHg). blood gas analysis showed oxygen saturation of 83% in the pulmonary artery. Angiography of the pulmonary arteries showed intrastent restenosis on the left pulmonary artery and fracture of the stent on the right pulmonary artery. For which was performed angioplasty with stent intrastent implantation in the right pulmonary artery. After the procedure there was immediate reduction in pulmonary mean arterial pressure (53 mmHg), a progressive improvement in 02 saturation (88% at discharge) while the echocardiogram after the procedure results unchanged except for the increasing of the systolic flow acceleration time (100 msec). Right catheterization showed a gradient trans-stenosis of 96 mmHg. We performed angioplasty with stent intrastent implantation in the right pulmonary artery. After that we saw a drop in the gradient trans-stenosis (63 mmHg) and a raise in the systolic pressure of the left pulmonary artery. In Conclusion, in this particular population of patients with pulmonary hypertension even if on maximal therapy, the worsening of symptoms should in our opinion be an indication for right cardiac catheterization and angiography of the pulmonary arteries.

Association of Clinical and Laboratory Findings in COVID-19 Patients with Thromboembolic Complications

Background: COVID-19 is associated with dangerous thromboembolic complications, such as stroke, heart attack, pulmonary embolism, and arterial and venous thromboembolism (VTE). Early diagnosis and even prediction of thromboembolic complications using biomarkers could facilitate the treatment and decrease the mortality rate. Objectives: This study evaluated and compared the clinical and laboratory findings of COVID-19 patients with thrombotic events with other COVID-19 patients. Methods: A total of 114 confirmed COVID-19 patients referred to Taleghani Hospital, Tehran, Iran, between February and September 2020 were included in this cross-sectional study. Those with a history of thromboembolic disease were excluded. The laboratory data, including the levels of lactate dehydrogenase (LDH), D-dimer, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and counts of lymphocyte and neutrophil, along with clinical findings (such as oxygen saturation and lung involvement percentage), were retrospectively collected from the patients’ clinical files. The incidence of thrombotic events was evaluated in patients. Results: The prevalence of thrombosis in the right and left main pulmonary arteries, right and left sub-segmental pulmonary arteries, and right and left deep veins was 2.7%, 3.5%, 7%, 7.9%, 4.4%, and 1.8% of all patients, respectively. The results showed that thromboembolic complications were significantly associated with mortality (P &lt; 0.001). Besides, it was found that LDH (P &lt; 0.001) and neutrophil (P = 0.002) levels in thromboembolic COVID-19 patients were respectively higher and lower than those without thromboembolic manifestations. Conclusions: High LDH and neutropenia might serve as biomarkers for thromboembolism in COVID-19 patients.

Role of noncontrast magnetic resonance pulmonary imaging in diagnosis of pulmonary embolism

Background Pulmonary embolism (PE) is a serious condition and has a clinical dilemma in diagnosis. Computed tomography pulmonary angiography (CTPA) is a gold standard in its diagnosis, but MRI has proven a good role in PE diagnosis. Aim The aim of this work was to evaluate the role of noncontrast magnetic resonance pulmonary angiography (MRPA) imaging in diagnosis of acute PE using CTPA as a gold standard. Patients and methods In total, 25 patients with PE confirmed by CTPA were included in this study. All patients underwent computed tomography angiography and noncontrast MRPA on the same day or within three consecutive days. The results were compared and statistically analyzed. Results The mean age of the study group was 46.4 ± 13.5 years. Females represent 60% (15/25) and males represent 40% (10/25). The per-vessel sensitivity of noncontrast MRPA reached to about 100% with specificity 100% at the level of the main trunk, right and left main pulmonary arteries down to segmental arteries. The sensitivity for right subsegmental branches was 25% and left subsegmental branches was 33.3%. Conclusion The noncontrast MRPA has a reasonable sensitivity and specificity in the diagnosis of PE, especially in major branches. So, it can be used as an alternative to the computed tomography angiography, especially when the computed tomography angiography and the use of gadolinium are contraindicated.

OUTCOMES FROM CATHETER-DIRECTED EMBOLECTOMY FOR INTERMEDIATE-RISK AND HIGH-RISK PULMONARY EMBOLISM

OUTCOMES FROM CATHETER-DIRECTED EMBOLECTOMY FOR INTERMEDIATE-RISK AND HIGH-RISK PULMONARY EMBOLISM

RAPIDLY PROGRESSIVE POST-TRANSPLANT LYMPHOPROLIFERATIVE DISORDER AFTER LUNG TRANSPLANTATION

TYPE: Case Report TOPIC: Transplantation INTRODUCTION: Posttransplant lymphoproliferative disorder (PTLD) after lung transplantation occurs due to immunosuppressant therapy, which limits antiviral host immunity and permits Epstein-Barr viral (EBV) replication and B cell transformation. CASE PRESENTATION: A 67-year-old female, bilateral lung transplant recipient (07/2019) with a history of idiopathic pulmonary fibrosis developed rapidly progressive PTLD in the early postoperative course. DISCUSSION: At 6-months after transplant, chest radiographs revealed left hilar fullness; subsequent chest CT showed evidence of fluid in the fissure, with no obvious lymphadenopathy. Chest CT performed just two weeks later revealed a left hilar mass measuring 6.1 × 2.7 cm with encasement of the left main pulmonary artery and partial collapse of the left main bronchus. Endobronchial ultrasound-guided biopsies led to the diagnosis of CD20-positive, EBV-positive PTLD. Initial PET scan demonstrated multiple hilar lymph nodes, the largest measuring 2.2 × 2.8 cm. Immunosuppression was reduced, and because the PTLD involved only one area in an EBV-mismatched bilateral lung transplant recipient, she qualified for single-agent rituximab once/week. Unfortunately, repeat imaging after five doses of rituximab demonstrated significant disease progression. She required repeat bronchoscopy with tumor debulking for a necrotic, endobronchial tumor occluding up to one-half of the left lower lobe bronchus. She started R-mini-CHOP, and after three cycles of chemotherapy, complete response was observed on the most recent PET/CT scan. CONCLUSIONS: PTLD may progress quickly, as the initial chest CT scan showing fluid collection advanced rapidly into a hilar mass. Reduction in immunosuppression, anti-CD20 biologic therapy, and chemotherapy for refractory PTLD remains an appropriate treatment paradigm. DISCLOSURE: Nothing to declare. KEYWORD: Post-lung transplant lymphoproliferative disorder

Pulmonary Artery Dissection In A Patient With Heartmate 3 Left Ventricular Assist Device

Pulmonary Artery Dissection In A Patient With Heartmate 3 Left Ventricular Assist Device

A CASE OF INTRA-OPERATIVE INJURY TO LEFT MAIN PULMONARY ARTERY REPAIRED WITH A PERICARDIAL PATCH

Introduction: Patients with central lung tumours often undergo surgery, offering them a chance of cure. With central lung tumours, there is always the dreaded risk of injury to the left main pulmonary artery (PA) and rupture of the anterior segmental artery, known as the artery of sorrow. Case Presentation: A 75-year-old lady with a background of breast cancer presented to our cardiothoracic centre because computed tomography (CT) of the chest revealed a left lung lesion of 5 x 4 x 3.7 cm, in contact with oblique fissure, radiological staging T3 N2 M0, which was later shown to be highly avid on positron emission tomography (PET-CT). Resection via thoracotomy was done, due to dense attachment to PA, Left PA defect was noted after resection which was repaired with a pericardial patch with no post-operative complication. Discussion: In the event of tumours invading the PA, it is safe to divide the tumours completely and repair the PA using a patch if there are any complications. Conclusion: We performed a repair of the PA using a pericardial patch and reconstruction of the PA using a pericardial patch, and evidence shows that there is excellent long-term survival associated with this.

A case of left main pulmonary artery occlusion test under general anesthesia with isolated pulmonary ventilation in a patient with left lung cancer after Fontan surgery

A case of left main pulmonary artery occlusion test under general anesthesia with isolated pulmonary ventilation in a patient with left lung cancer after Fontan surgery

Evaluation of the relationship between chronic small airway diseases and pulmonary artery diameter on computed tomography

Purpose: To study that how the non-asthma chronic obstructive pulmonary diseases (non-asthma-COPD) affect pulmonary artery diameters. Methods: The main pulmonary artery diameter (MPAD), right and left main pulmonary artery diameter (RPAD-LPAD), and the ratio of MPAD to ascending aorta diameter (AAD) (MPAD/AAD) in all subjects of the sample were assessed. Cases with non-asthma-COPD were classified as Group 1; those who were not was categorized into Group 2. The link between non-asthma-COPD and diameters of pulmonary artery and also the ratio of MPAD/AAD was evaluated statistically according to the groups. Results: In the study in which a total of 905 cases were evaluated, 138 in Group 1; 767 in Group 2. The patients' average age was 44.82 ± 16.53 (18-82). It was discovered that there is a statistically significant relationship between MPAD, RPAD and LPAD values and non-asthma-COPD, and it was higher in Group 1 (p=0.049, p=0.011, p=0.022; p<0,05, respectively). The MPAD/AAD value of the cases in Group 1 was discovered to be slightly higher than Group 2 (p=0.006; p<0,01). While the cut-off value for MPAD is ≥23.5 mm, the odds ratio was 1.573 (95% CI: 1.092-2.267); while the cut-off value for MPAD/AAD was ≥0.88, the odds ratio was 1.918 (95% CI: 1.253-2.938). According to ROC analysis, MPAD values were more specific for non-asthma-COPD than MPAD/AAD ratio, but MPAD/AAD ratio was more sensitive. Conclusion: Although there is a relationship between non-asthma-COPD and MPAD, RPAD, LPAD; the ratio of MPAD /AAD is more sensitive for the presence of non-asthma-COPD.