Effects of exercise on monocrotaline-induced changes in right heart function and pulmonary artery remodeling in rats

2013 ◽  
Vol 91 (1) ◽  
pp. 38-44 ◽  
Author(s):  
Rafael Colombo ◽  
Rafaela Siqueira ◽  
Cristiano Urbano Becker ◽  
Tânia Gatelli Fernandes ◽  
Karla Maria Pires ◽  
...  

Pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT) is an experimental protocol of right heart failure. We analyzed the role of exercise training on the right ventricle structure and function, pulmonary artery remodeling, and GSK-3β expression. Rats were divided among the following groups: sedentary control (SC), sedentary monocrotaline (SM), trained control (TC), and trained monocrotaline (TM). Rats underwent exercise training for a period of 5 weeks, with 3 weeks post-MCT injection. Rats in the SM and TM groups presented with an increase in right ventricle hypertrophy indexes and lung congestion. The right ventricular end diastolic pressure (RVEDP), right ventricular systolic pressure (RVSP), and its minimum and maximal pressure derivates were increased in the SM and TM groups. The right ventricle interstitial volume pulmonary artery thickness and p-GSK-3β/GSK-3β were increased in the MCT groups as compared with the control groups. The TM group had a reduction in interstitial volume, p-GSK-3β/GSK-3β ratio, pulmonary artery thickness, RVEDP, and an increase in intramyocardial vessels volume as compared with the SM group. The overall results have shown that the exercise protocol used promoted positive changes in right ventricle and pulmonary artery remodeling. These observations also suggest that structural remodeling may be influenced by signaling proteins, such as GSK-3β.

2017 ◽  
Vol 136 (3) ◽  
pp. 262-265 ◽  
Author(s):  
Turgut Karabag ◽  
Caner Arslan ◽  
Turab Yakisan ◽  
Aziz Vatan ◽  
Duygu Sak

ABSTRACT CONTEXT: Obstruction of the right ventricular outflow tract due to metastatic disease is rare. Clinical recognition of cardiac metastatic tumors is rare and continues to present a diagnostic and therapeutic challenge. CASE REPORT: We present the case of a patient who had severe respiratory insufficiency and whose clinical examinations revealed a giant tumor mass extending from the right ventricle to the pulmonary artery. We discuss the diagnostic and therapeutic options. CONCLUSION: In patients presenting with acute right heart failure, right ventricular masses should be kept in mind. Transthoracic echocardiography appears to be the most easily available, noninvasive, cost-effective and useful technique in making the differential diagnosis.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Julio Brito ◽  
Patricia Siques ◽  
Silvia M. Arribas ◽  
Angel L. López de Pablo ◽  
M. Carmen González ◽  
...  

Long-term chronic intermittent exposure to altitude hypoxia is a labor phenomenon requiring further research. Using a rat model, we examined whether this type of exposure differed from chronic exposure in terms of pulmonary artery remodeling and other features. Rats were subjected to chronic hypoxia (CH,n=9) and long-term intermittent hypoxia (CIH2x2; 2 days of hypoxia/2 days of normoxia,n=10) in a chamber (428 Torr, 4,600 m of altitude) for 46 days and compared to rats under normoxia (NX,n=10). Body weight, hematocrit, and right ventricle ratio were measured. Pulmonary artery remodeling was assessed using confocal microscopy of tissues stained with a nuclear dye (DAPI) and CD11b antibody. Both hypoxic conditions exhibited increased hematocrit and hypertrophy of the right ventricle, tunica adventitia, and tunica media, with no changes in lumen size. The medial hypertrophy area (larger in CH) depicted a significant increase in smooth muscle cell number. Additionally, CIH2x2 increased the adventitial hypertrophy area, with an increased cellularity and a larger prevalence of clustered inflammatory cells. In conclusion, CIH2x2 elicits milder effects on pulmonary artery medial layer muscularization and subsequent right ventricular hypertrophy than CH. However, CIH2x2 induces greater and characteristic alterations of the adventitial layer.


2020 ◽  
Author(s):  
Song Jiyang ◽  
Wan Nan ◽  
Shen Shutong ◽  
Wei Ying ◽  
Cao Yunshan

Abstract Background: Right ventricular (RV) failure induced by sustained pressure overload is a major contributor to morbidity and mortality in several cardiopulmonary disorders. Reliable and reproducible animal models of RV failure are important in order to investigate disease mechanisms and effects of potential therapeutic strategies. To establish a rat model of RV failure perfectly, we observed the right ventricle and carotid artery hemodynamics characteristics in different degrees of pulmonary artery banding of rats of different body weights. Methods: Rats were subjected to 6 groups:control(0%, n=5)(pulmonary arterial banding 0%), PAB(1-30%, n=4)(pulmonary arterial banding1-30%), PAB(31-60%, n=6)(pulmonary arterial banding31-60%),PAB(61-70%, n=5)(pulmonary arterial bandin61-70%), PAB(71-80%,n=4)(pulmonary arterial banding71-80%), PAB(100%, n=3)(pulmonary arterial banding 100%). We measured the right ventricular pressure(RVP) by right heart catheterization when the pulmonary arterial was ligated. Results: The RVP gradually increased with increasing degree of banding, but when occlusion level exceeding 70%, high pressure state can be only maintained for a few minutes or seconds, and then the RVP drops rapidly until it falls below the normal pressure, which in Group F particularly evident.Conclusions: RVP have different reactions when the occlusion level is not the same, and the extent of more than 70% ligation is a successful model of acute right heart failure. These results may have important consequences for therapeutic strategies to prevent acute right heart failure.


Author(s):  
R. M. Vitovsky ◽  
P. M. Semeniv ◽  
A. O. Rusnak ◽  
Y. R. Ivanov ◽  
V. F. Onischenko

The case of differential diagnosis and treatment of a patient with pulmonary embolism (PE), the source of which was the thrombus formed in the right ventricle of the heart, is presented. The peculiarity of this case was the untimely diagnosis of the disease, which simulated pneumonia, the treatment of which did not improve the clinical condition of the patient. Tomography allowed to determine the thrombosis of the right branch of the pulmonary artery and to send the patient to the cardiac surgery center for further treatment. Diagnosis of a probable source of embolism occurred after echocardiography, which revealed a tumor-like lesion of the right ventricle of large size and dense consistency. The results of surgical treatment of the patient, during which extensive formation of the right ventricle was removed, a dense elastic consistency with signs of fragmentation confirmed the prediction of this particular source of pulmonary embolism. Removal of blood clots from the right branch of the pulmonary embolism showed their similar macrostructure with right ventricular formation. The appearance and macrostructure of the formation did not allow to determine with certainty its character. Only histological examination was able to determine the thrombogenicity of the origin of this formation. The recurrent nature of pneumonia, without the presence of risk factors, in young patients may be the basis for more thorough examination to identify atypical clinical conditions. The restoration of the source of the body is of great importancefor the prevention of its relapse. Finding the source of pulmonary embolism should necessarily include echocardiography to carefully examine possible lesions of intracardiac structures with the formation of blood clots that may be responsible for its occurrence.


2018 ◽  
Vol 38 (4) ◽  
pp. 218-225
Author(s):  
Emir Yonas ◽  
Raymond Pranata ◽  
Nuvi Nusarintowati

Introduction: Pulmonary atresia with an intact ventricular septum is a condition that is characterized by a complete obstruction to right ventricular outflow with varying degrees of right ventricular and tricuspid valve hypoplasia. This condition is uniformly fatal if untreated. In this case report, we present a case of a neonate with a pulmonary atresia with intact ventricular septum Case Presentation: A 2 days-old female Indonesian newborn was referred to our facility. The newborn was delivered from a G4P3A0 mother with a gestational age of 39 weeks (term delivery). Chest x-ray done at the referring facility is significant for a seemingly right heart hypertrophy, casting a “boot-shaped” appearance of the right heart border. Laboratory results done at the referring facility is significant for a neutrophilia of 82% and lymphocytopenia of 13% An episode of hypoglycemia was reported on referring facility with a blood sugar level of 50 mg/dl. Multiple episodes of cyanosis were reported at referring facility, CPAP was administered but the improvement was limited. Pulse oximetry averaged between 72-80% at the referring facility. Physical examina­tion shows an actively moving neonate, with a strong cry. Perioral cyanosis was seen. Vital signs were as follows; heart rate 128 x / minute, temperature 37oC, respiratory rate 54 x / minute, pulse oximetry 74%, capillary refill time < 3 seconds. The rest of the physical examination was within normal limits. Laboratory result on admission at our facility is significant for low hematocrit, low erythrocyte count, leukopenia with neutrophilia and thrombocytopenia. Patient was admitted to NICU and given CPAP. Echocardiography 2 days upon arrival at our facility reveals a patent ductus arteriosus with the pressure of 4-5 mmHg and diameter of 0.3 cm, no forward flow from the right ventricle to the pulmonary artery, doppler mode demonstrated pulmonary artery filling from ductus arteriosus. The rest of the findings were within normal limits. Conclusion: Pulmonary atresia with an intact ventricular septum is a condition that relies on the patent ductus arteriosus for pulmonary blood supply, the patency of it is of paramount importance.   Abstrak PENDAHULUAN: Atresia arteri pulmonalis dengan septum ventrikel yang utuh merupakan kondisi yang dikarakterisasikan dengan sumbatan total pada right ventricular outflow dengan berat hipoplasia ventrikel kanan dan trikuspid kanan yang beratnya bervariasi. Pada umumnya kondisi tersebut fatal apabila tidak ditangani. Pada laporan kasus ini, kami melaporkan suatu kasus neonates dengan atresia arteri pulmonalis dengan septum ventrikel yang utuh. PRESENTASI KASUS: Neonatus perempuan berumur 2 hari dirujuk ke rumah sakit kami. Bayi dilahirkan dari G4P3A0 usia kehamilan 39 minggu. Ronsen thoraks yang dilakukan oleh fasilitas kesehatan yang merujuk memperlihatkan hipertrofi jantung kanan serta bentuk “boot-shaped” pada batas jantung kanan. Hasil laboratorium pada fasilitas kesehatan tersebut menunjukan neutrofilia dan limfositopenia. Terdapat juga riwayat hipoglikemi. Episode sianosis berulang terjadi pada fasilitas kesehatan yang merujuk. Pemasangan CPAP kurang membuahkan hasil dengan saturasi O2 72-80% ketika tiba pada rumah sakit kami. Pemeriksaan fisik menunjukan tangis kuat dan gerak aktif dengan sianosis perioral. Detak jantung 128 kali/menit, suhu 37oC, laju naas 54 kali/menit, oksimetri nadi 74% dan waktu isi kapiler <3 detik. Pemeriksaan laboratorium saat pasien dating menunjukan hematocrit, hitung eritrosit, leukosit dan thrombosit yang rendah. Pasien dirawat di NICU dan diberikan CPAP. Ekokardiografi 2 hari kemudian menunjukan duktus arteriosus patent dengan tekanan 4-5 mmHg dan diameter 0.3 cm, tidak ada aliran maju dari ventrikel kanan kepada arteri pulmonalis, mode Doppler menunjukan pengisian arteri pulmonalis dari duktus arteriosus. Pemeriksaan lainnya dalam batas normal. KESIMPULAN: Atresia arteri pulmonalis dengan septum ventrikel yang utuh merupakan suatu kondisi dimana aliran darah menuju paru bergantung pada duktus arteriosus yang paten sehingga patensi daripada duktus tersebut sangatlah penting


2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
F Ferrara ◽  
L Gargani ◽  
M Guazzi ◽  
M D"alto ◽  
K Wierzbowska Drabik ◽  
...  

Abstract Funding Acknowledgements no funding sources exists OnBehalf RIGHT Heart International NETwork (RIGHT-NET) Purpose Exercise stress echocardiography (ESE) is a well-validated tool in ischemic and valvular heart diseases. The aim of this study is to assess the ESE feasibility for the evaluation of the right heart pulmonary circulation unit (RH-PCU) in a large cohort of subjects, from healthy individuals and elite athletes to patients with overt or at risk of developing pulmonary hypertension. Methods: 954 subjects [mean age 54.2 ± 16.4 years, 430 women] [254 healthy volunteers, 40 elite athletes, 363 patients with cardiovascular risk factors, 25 with pulmonary arterial hypertension, 149 with connective tissue diseases, 81 with left heart and valvular diseases, 42 with lung diseases], underwent standardized semi-recumbent cycle ergometer ESE with an incremental workload of 25 watts every 2 minutes up to symptom-limited maximal tolerated workload. ESE parameters of right heart structure, function and pressures were obtained according current recommendations. Results: The success rate for the evaluation of the RV function at peak exercise was 903/940 (96%) for tricuspid annular plane systolic excursion (TAPSE), 667/751 (89%) for tissue Doppler–derived tricuspid lateral annular systolic velocity (S’) and 425/772 (63%) for right ventricular fractional area change (RVFAC). Right ventricular–right atrial pressure gradient [RV-RA gradient = 4 x tricuspid regurgitation velocity2] was obtained in 894/954 patients (93.7 %) at rest and in 816/954 (85.5%) at peak exercise. At peak exercise, pulmonary acceleration time (AcT) was feasible among 435/545 (82.5%) patients (Table 1). Conclusions: In daily ESE monitoring of TAPSE and S’ resulted to be less challenging than of RV FAC. ESE was a feasible tool for the evaluation of RV-RA gradient and pulmonary AcT. Table 1 Parameters Rest mean ± SD Peak mean ± SD P value Assessed n (%) Feasibility at rest n (%) Feasibility at peak n (%) RVED area (cm2) 17.4 ± 5.7 17.4 ± 5.8 0.9 672 632 (94.0) 425 (63.2) RVES area (cm2) 9.7 ± 4.3 9.6 ± 4.9 0.7 672 632 (94.0) 425 (63.2) TAPSE (mm) 22.9 ± 3.9 27.4 ± 5.5 &lt;0.001 940 922 (98.1) 903 (96.0) S’(cm/s) 13.1 ± 2.9 18.5 ± 5.0 &lt;0.001 751 746 (99.4) 667 (88.8) RVFAC (%) 45.7 ± 10 46.7 ± 11 0.121 672 632 (94.0) 425 (63.2) RV-RA gradient (mmHg) 24.3 ± 15 42.5 ± 20 &lt;0.001 954 894 (93.7) 816 (85.5) Pulmonary AcT (m/s) 129 ± 31 116 ± 35 &lt;0.001 545 527( 96.7) 435 (82.5) RVED, right ventricle end diastolic area; RVES, right ventricle end systolic area; p values indicate differences at rest and peak exercise. The term “assessed” indicates that an attempt was done in order to measure the parameter. The term “feasibility” indicates that it was possible to measure the parameter that was assessed.


2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
E Ayduk ◽  
P Karaca Ozer ◽  
M Dursun ◽  
S Umman ◽  
Y C Toktas ◽  
...  

Abstract A 25 years old male patient was referred to an advanced center because of 2/6-degree systolo-diastolic murmur heard at meso-cardiac area during his pre-military routine examination. ECG revealed T wave inversions at standard D1 to D3 and precordial V1 to V4 leads, treadmill was non-diagnostic for ischemia. In his transthoracic echocardiogram, measurement of heart chambers and wall thicknesses were within normal range with normal wall motion of the left ventricle, EF was 55%. 2D and color-Doppler echocardiography revealed a cystic structure with venous flow in it at the right ventricular apex, and created a suspicion of a fistula. Myocardial perfusion scintigraphy showed ischemia at the apical sections of the septal wall. He underwent coronary angiography, LMCA and proximal LAD were ectatic, LAD ectasia was in consistent with the first septal branch, circumflex (Cx) and right coronary artery (RCA) angiograms were normal. LAD flow was examined and no fistula was detected. Right and left ventriculography revealed normal ventricular functions, oxygen saturations were 70.9% in pulmonary artery, 70.4% in right ventricle, 72.9% in right atrium, and 97.4% in the aorta. Pulmonary capillary wedge pressure was 10 mmHg, pulmonary artery pressure 10/26/5 mmHg, right ventricular pressure 13/6 mmHg, left ventricular pressure 120/0/8 mmHg. Further investigations for etiology and congenital malformations were planned and the patient was discharged with oral anticoagulant therapy. The patient had no contact with the outpatient clinic for 17 years. At the 17th year of the diagnosis he was called and reevaluated. He was still asymptomatic and oscultation findings were the same. Transthoracic 2D and 3D and color-Doppler echocardiography revealed the same cystic structure at the right ventricular apex, but this time with no-flow. Coronary CT angiography was performed, LMCA was ectatic and the diameter was 8.1 mm, proximal LAD was ectatic and the diameter was 6 mm, ectasia was in continuous with the first septal branch. The ectatic septal branch was at the apical level of the right ventricle, appearing like a cystic structure with a diameter of 2.8 cm, and the lack of contrast enhancement was thougt to be in consistent with thrombus formation. Cx and RCA artery calibrations were found to be normal. In order to confirm the diagnosis of thrombus formation, MR angiography was performed. Perfusion MRI showed no evidence of thrombus in the ectatic septal branch. Abstract P706 Figure.


1975 ◽  
Vol 228 (1) ◽  
pp. 223-230 ◽  
Author(s):  
Y Uchida

Mechanosensitivity of afferent sympathetic nerve fibers from the right heart and the pulmonary artery has been examined. Action potentials of the afferent fibers that responded to tapping the right heart and the pulmonary artery were derived from upper thoracic communicating rami of both sides of anesthetized dogs. The fibers were composed of myelinated Adelta fibers and unmyelinated fibers. The receptive fields of both groups of fibers were located widely in the right heart and the pulmonary artery. Myelinated fibers ceased to fire quickly whereas unmyelinated fibers continued to fire after withdrawl of a brief mechanical stimulus. In the myelinated group, the pressure threshold was 3-50, 6-58, and 3-10 mmHg for right ventricular, pulmonary and right atrial threshold was 15-58, 22-34, and 4-8 mmHg for right ventricular, pulmonary, and right atrial fibers, respectively. Spontaneous discharge of myelinated fibers was synchronous with each rise and/or fall in intracardiac or pulmonary pressure whereas that of unmyelinated fibers was irregular and independent. A rise in pressure produced by pulmonary embolization or occlusion caused an augumented discharge whereas a fall caused by caval vein occulsion eliminated the discharge. The results indicate the existence of both myelinated and unmyelinated fibers with mechanoreceptors in the right heart and the pulmonary artery.


2002 ◽  
Vol 205 (13) ◽  
pp. 1843-1851 ◽  
Author(s):  
Douglas A. Syme ◽  
Kurt Gamperl ◽  
David R. Jones

SUMMARYAlligators and other crocodilians have a cog-wheel valve located within the subpulmonary conus, and active closure of this valve during each heart beat can markedly and phasically increase resistance in the pulmonary outflow tract. If this increased resistance causes right ventricular pressure to rise above that in the systemic circuit, right ventricular blood can flow into the left aorta and systemic circulation, an event known as pulmonary-to-systemic shunting. To understand better how this valve is controlled, anaesthetized American alligators (Alligator mississippiensis) were used to examine the relationships between depolarization of the right ventricle,depolarization/contraction of the cog-wheel valve muscle and the resultant right ventricular, pulmonary artery and systemic pressures. Depolarization swept across the right ventricle from the apex towards the base (near where the cog-wheel valve muscle is located) at a velocity of 91±23 cm s-1 (mean ± S.E.M., N=3). The cog-wheel valve electrocardiogram (ECG) (and thus contraction of the valve) trailed the right ventricular ECG by 248±28 ms (N=3), which was equivalent to 6-35 % of a cardiac cycle. This long interval between right ventricular and valve depolarization suggests a nodal delay at the junction between the base of the right ventricle and the cog-wheel valve. The delay before valve closure determined when the abrupt secondary rise in right ventricular pressure occurred during systole and is likely to strongly influence the amount of blood entering the pulmonary artery and thus to directly control the degree of shunting. Left vagal stimulation (10-50 Hz) reduced the conduction delay between the right ventricle and cog-wheel valve by approximately 20 % and reduced the integrated cog-wheel ECG by 10-20 %. Direct application of acetylcholine (1-2 mg) also reduced the integrated cog-wheel ECG by 10-100 %;however, its effect on the conduction delay was highly variable (-40 to +60%). When the cog-wheel valve muscle was killed by the application of ethanol,the cog-wheel ECG was absent, right ventricular and pulmonary pressures remained low and tracked one another, the secondary rise in right ventricular pressure was abolished and shunting did not occur. This study provides additional, direct evidence that phasic contraction of the cog-wheel valve muscle controls shunting, that nervous and cholinergic stimulation can alter the delay and strength of valve depolarization and that this can affect the propensity to shunt.


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