Longitudinal extension of the pulmonary trunk during breathing in young rabbits: a possible factor in elastin fragmentation

1976 ◽  
Vol 54 (2) ◽  
pp. 113-117
Author(s):  
Paul H. Smith

Corrosion casts of the pulmonary trunk and major branches of the pulmonary arteries of 39 rabbits were made from a silicone polymer. In half of the rabbits the casts were made with the lungs expanded and half with the lungs collapsed. The length of various segments of the casts were measured from magnified photographs. It was found that in rabbits less than 23 days old the pulmonary trunk is significantly longer when the lungs are expanded than when they are collapsed. This suggests that a repeated longitudinal extension of the vessel occurs during breathing. This effect disappears after 30 days of age, possibly because of elastin fragmentation. Between the ages of 23 and 30 days the growth in length and diameter of the pulmonary trunk undergoes a rapid acceleration. This may also be the result of elastin fragmentation. Whereas it may be that repeated longitudinal stress in the pulmonary trunk during breathing causes elastin in its media to fragment, one cannot exclude the possibility that other factors such as growth are responsible.

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
K Starzyk ◽  
P Dybich ◽  
K Ciuraszkiewicz ◽  
W Rokita ◽  
B Wozakowska-Kaplon

Abstract Pulmonary embolism is one of the leading causes of maternal mortality despite a low incidence of during pregnancy. We present 32-year-old woman, in the 35 week of first pregnancy, admitted to the Intensive Care Unit with dyspnea, tachycardia, cyanosis. Echocardiography confirmed the presence of embolic material in the main trunk of pulmonary artery, spreading to the right pulmonary artery. D-dimer and troponin T level were elevated, BNP remained within the normal range. The risk in PESI scale was assumed as intermediate high. LMWH therapy was initiated, the patient was constantly monitored. Venous thrombotic disease in lower extremities was excluded by ultrasonography. The treatment was carried out under obstetric supervision. The clinical state gradually improved, the patient was hemodynamically stable. Serial echocardiographic testing, revealed gradual regression of changes in the pulmonary trunk. Normalization of troponins and lowering of BNP levels were observed. The pregnancy was terminated in 39 week, by cesarean section (obstetric indications). The LMWH was continued few days after delivery, as the patient started lactation. She decided to terminate lactation in a first week after delivery so the therapy was switched into rivaroxaban for at least 3 months. Echocardiography after 3 month confirmed lack of changes in pulmonary trunk, the risk of pulmonary hypertension was low. Echocardiography can be a method of choice for confirming and monitoring pulmonary embolism during pregnancy, in a situation of high or intermediate clinical risk and good visualization of changes in pulmonary arteries Abstract P701 Figure. Embolism of pulmonary trunk and RPA


1995 ◽  
Vol 19 (1) ◽  
pp. 61-106 ◽  
Author(s):  
Ian C. Willis

Variations in glacier horizontal and vertical motion occur at a variety of intra-annual timescales: monthly, daily and even hourly. These variations have been identified from measurements made both beneath and on the surface of glaciers. They must be associated with variations in basal motion rather than changes in internal ice-deformation rates. Variations in basal motion result from changes in sliding rates over a 'hard bed' (i.e., rigid bedrock) or changes in deformation rates within a 'soft bed' (i.e., unlithified permeable till). Changes in both sliding and bed deformation rates are related to variations in subglacial water pressures and therefore depend critically on the structure of the subglacial drainage system and the hydraulics of individual drainage passageways. Thus changes in subglacial drainage system structure and drainage passageway hydraulics can cause intra-annual variations in glacier motion. However, intra-annual variations in glacier motion will also be influenced by variations in longitudinal stress gradients as a result of changes in the rate of longitudinal extension and compression.


1964 ◽  
Vol 68 (5) ◽  
pp. 612-620 ◽  
Author(s):  
Ivan A. D'Cruz ◽  
Rene A. Arcilla ◽  
Magnus H. Agustsson

1994 ◽  
Vol 4 (4) ◽  
pp. 402-404 ◽  
Author(s):  
Kiyoshi Suzuki ◽  
Toshio Kikuchi ◽  
Shigekazu Mimori

SummaryWe describe a rare type of atrioventricular septal defect with common atrioventricular orifice and malaligned atrial septum, the latter feature resulting in severe obstruction of the left atrial egress. Excision of the atrial septum and banding of the pulmonary trunk was performed at the age of thirteen months. Lung biopsy demonstrated marked medial hypertrophy with severe intimal fibrosis in the small pulmonary arteries and mild thickening of the pulmonary veins, considered contraindications for corrective surgery.


2018 ◽  
Vol 2018 ◽  
pp. 1-4
Author(s):  
E. Fry ◽  
J. Urbanczyk ◽  
J. Price ◽  
R. Digiovanni ◽  
M. Jepson ◽  
...  

Purulent pericarditis is a rare disease in the era of antibiotics, with Streptococcus pyogenes being a possible, though uncommon etiology. Even more uncommon are mycotic aneurysms secondary to group A strep purulent pericarditis and bacteremia. We report a case of an 18-year-old female with a history of strep pharyngitis develop Streptococcus pyogenes purulent pericarditis with subsequent ventricular fibrillation (VF). Following initial stabilization, she ultimately developed a 4.8 cm mycotic aneurysm of the ascending aorta, with resultant compression of the pulmonary trunk and right pulmonary arteries.


Author(s):  
Büşra Pirinç ◽  
Zeliha Fazlıoğulları ◽  
Mustafa Koplay ◽  
Ahmet Kağan Karabulut ◽  
Nadire Ünver Doğan

2020 ◽  
Vol 10 ◽  
pp. 5
Author(s):  
Pierre D. Maldjian ◽  
Kevin R. Adams

We report a case of a partial anomalous left pulmonary artery sling in an adult patient as an incidental finding on computed tomography. There is a normal bifurcation of the pulmonary trunk into right and left pulmonary arteries with anomalous origin of the left upper lobe pulmonary artery from the right pulmonary artery. The anomalous vessel passes between the trachea and esophagus forming a partial left pulmonary artery sling without airway compression.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 681-682
Author(s):  
X. Kong ◽  
L. MA ◽  
P. LV ◽  
X. Cui ◽  
R. Chen ◽  
...  

Background:Takayasu arteritis (TA) is a chronic, granulomatous large-vessel vasculitis. It involves the aorta and its main branches predominantly, and leads to vascular thickness, stenosis and occlusion [1]. Besides the aorta and its branches, pulmonary arteries (PAs) are involved in TA. PAs have been reported to be involved in 6.9% to 80% of TA patients from different populations [2-3].Objectives:We investigated the clinical characteristics, pulmonary parenchymal features and cardiac functions in TA patients with PA involvement by combining multiple imaging modalities (MRA, CTA, PET-CT, lung VQ scan, echocardiography and high-resolution computed tomography (HRCT)). Our aim was to elicit better understanding of TA patients with PA involvement to aid rational treatment for these patients and improve their prognosis.Methods:We enrolled 216 patients with TA from a large prospective cohort. PAI was assessed in each patient based on data from magnetic resonance angiography/computed tomography angiography. Pulmonary hypertension, cardiac function, and pulmonary parenchymal abnormalities were evaluated further in patients with PAI based on echocardiography, New York Heart Association Functional Classification and pulmonary computed tomography, respectively. These abnormalities related to PAI were followed up to evaluate treatment effects.Results:PAI was detected in 56/216 (25.93%) patients, which involved the pulmonary trunk, main PAs and small vessels in the lungs. Among patients with PAI, 28 (50%) patients were accompanied by pulmonary hypertension, which was graded as ‘severe’ in 9 (16.07%), ‘moderate’ in 10 (17.86%) and mild in 9 (16.07%). Forty (71.43%) patients had cardiac insufficiency (IV: 6, 10.71%; III: 20, 35.71%; II: 14, 25.00%). Furthermore, 21 (37.50%) patients presented with abnormal parenchymal features in the area corresponding to PAI (e.g., the mosaic sign, infarction, bronchiectasis). During follow-up, two patients died due to abrupt pulmonary thrombosis. In the remaining patients, the abnormalities mentioned above improved partially after routine treatment.Conclusion:PA involvement is very common in TA patients. Physicians should be alerted to PA involvement even if obvious pulmonary symptoms are absent because they can cause PH, cardiac insufficiency as well as pulmonary parenchymal lesions, which will worsen the prognosis.References:[1]M.L.F. Zaldivar Villon, J.A.L. de la Rocha, L.R. Espinoza. Takayasu Arteritis: Recent Developments. Curr Rheumatol Rep 2019; 21: 45.[2]N. Matsunaga, K. Hayashi, I. Sakamoto, et al. Takayasu arteritis: protean radiologic manifestations and diagnosis. Radiographics 1997; 17: 579-594.[3]M. Bicakcigil, K. Aksu, S. Kamali, et al. Takayasu’s arteritis in Turkey - clinical and angiographic features of 248 patients. Clin Exp Rheumatol 2009; 27: S59-64.Figure 1.Imaging of PA lesions in TA patientsA:Dilationof the pulmonary trunk; B: thickness of the pulmonary trunk; C: stenosis of the right main PA; D: embolism of lower PAs on both sides; E: inflammation of the pulmonary-trunk root upon PET–CT; F: absence of left PAs and stenosis of the right main PA; G–I: pulmonary MRA (G), CTA (H) and VQ scan (I) of a patient with TA. MRA shows a fine right main PA and low perfusion in the right lung (G); CTA demonstrates a fine right main PA and fewer PA branches in the right lung (H); lung VQ scan shows multiple arterial emboli in the right lung and obvious less blood supply to the right lung.Figure 2.Pulmonary lesions on HRCT.A: Themosaicsign in the left lung; B: Pulmonary infarction of the right middle lobe; C: Mild pleural effusion on the left side; D: Bronchiectasis in the right lung; E–F: Ground-glass opacity (E) in the right upper lobe of a TA patient with an embolism of the right upper pulmonary branches (F); G–I: Cavitation (G) and mass-like consolidation (H) in the patient with severe stenosis of right main pulmonary artery (I).Acknowledgments:NoneDisclosure of Interests:None declared


1991 ◽  
Vol 1 (2) ◽  
pp. 136-140 ◽  
Author(s):  
Ian A. Murdoch ◽  
Shakeel A. Qureshi ◽  
Rue Dos Anjos ◽  
Jonathan M. Parsons ◽  
Edward J. Baker ◽  
...  

SummaryBetween January 1985 and March 1990, 66 children with the tetralogy of Fallot underwent 85 cardiac catheterization procedures. The mean age at first procedure was 2.5 years (range 0.1–;14.4 years) and the mean weight was 10.4 kg ( range 2.4–36.0 kg). Diagnostic cardiac catheterization was performed in 60 procedures and balloon dilatation in 25. Hypercyanotic spells had occurred prior to 24 (28%) of the procedures (all the patients being on propranolol) and a systemic-to-pulmonary arterial shunt had been constructed before 28 (33%) procedures. Of the procedures, 54 (64%) were performed under local and 31(36%) under general anesthesia. The pulmonary trunk was entered antegradely in 52 procedures, retrogradely through a shunt in 6 and not entered in 27. Balloon dilatation was performed under general anesthesia on 25 occasions. No procedure was abandoned because of a cyanotic spell. Nine (11%) spells occurred during 86 procedures, one of the procedures being postponed because ofa spell occurring after premedication, the procedure and not, therefore, continuing to catheterization. Five spells occurred before the catheter was positioned in the heart, 2 spells occurred during catheterization. Of the spells, eight occurred during procedures in children who had not had previous shunts. Antegrade entry into the pulmonary trunk in the group with shunts was associated with no spells compared with 6/38 (18%) in the group not having undergone surgery (p<0.l). In the group not undergoing surgery, when the pulmonary trunk was not entered, 1 (5%) spell occurred during 19 procedures compared with 6/38 (18%) when the pulmonary trunk was entered (p<0.4). The only clinically important factor which significantly influenced the incidence of spells was the use of general anesthesia, which was associated with 6/31 (19%) spells compared with local anesthesia which was associated with 2/54 (4%) spells (p<0.026).


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