scholarly journals Evidence of Ventricular Arrhythmogenicity and Cardiac Sympathetic Hyperinnervation in Early Cirrhotic Cardiomyopathy

2021 ◽  
Vol 12 ◽  
Author(s):  
Shin-Huei Liu ◽  
Li-Wei Lo ◽  
Yu-Hui Chou ◽  
Wei-Lun Lin ◽  
Tsung-Ying Tsai ◽  
...  

Cirrhotic cardiomyopathy (CMP) is associated with altered cardiac electrophysiological (EP) properties, which leads to the risk of ventricular arrhythmias (VAs). We aimed to evaluate the EP properties, autonomic, and structural remodeling in a rabbit model with early liver cirrhosis (LC). Twelve rabbits were assigned to the sham and LC groups. The early-stage LC was induced by the ligation of the common bile duct. All rabbits received an EP study, VA inducibility test, myocardial, and liver histology staining. Western blot analyses of protein expression and tyrosine hydroxylase stain for sympathetic nerves were performed. The effective refractory period the LC group was significantly longer than the sham group [i.e., left ventricle (LV) 205.56 ± 40.30 vs. 131.36 ± 7.94 ms; right ventricle (RV) 206.78 ± 33.07 vs. 136.79 ± 15.15 ms; left atrium (LA) 140.56 ± 28.75 vs. 67.71 ± 14.29 ms; and right atrium (RA) 133.78 ± 40.58 vs. 65.43 ± 19.49 ms, all p < 0.01], respectively. The VA inducibility was elevated in the LC group when compared with the sham group (i.e., 21.53 ± 7.71 vs. 7.76 ± 2.44%, p = 0.013). Sympathetic innervation (102/μm2/mm2) was increased in all cardiac chambers of the LC group compared with the sham group (i.e., LV 9.11 ± 4.86 vs. 0.17 ± 0.15, p < 0.01; RV 4.36 ± 4.95 vs. 0.18 ± 0.12, p = 0.026; LA 6.79 ± 1.02 vs. 0.44 ± 0.20, p = 0.018; and RA 15.18 ± 5.12 vs. 0.10 ± 0.07, p = 0.014), respectively. Early LC is presented with an increased ventricular vulnerability, structural heterogeneity, and sympathetic innervation. Close monitoring for fatal arrhythmias is warranted in patients with early stages of LC.

2008 ◽  
Vol 295 (2) ◽  
pp. H691-H698 ◽  
Author(s):  
Alex Y. Tan ◽  
Shengmei Zhou ◽  
Byung Chun Jung ◽  
Masahiro Ogawa ◽  
Lan S. Chen ◽  
...  

The purpose of the present study was to determine whether thoracic veins may act as ectopic pacemakers and whether nodelike cells and rich sympathetic innervation are present at the ectopic sites. We used a 1,792-electrode mapping system with 1-mm resolution to map ectopic atrial arrhythmias in eight normal dogs during in vivo right and left stellate ganglia (SG) stimulation before and after sinus node crushing. SG stimulation triggered significant elevations of transcardiac norepinephrine levels, sinus tachycardia in all dogs, and atrial tachycardia in two of eight dogs. Sinus node crushing resulted in a slow junctional rhythm (51 ± 6 beats/min). Subsequent SG stimulation induced 20 episodes of ectopic beats in seven dogs and seven episodes of pulmonary vein tachycardia in three dogs (cycle length 273 ± 35 ms, duration 16 ± 4 s). The ectopic beats arose from the pulmonary vein ( n = 11), right atrium ( n = 5), left atrium ( n = 2), and the vein of Marshall ( n = 2). There was no difference in arrhythmogenic effects of left vs. right SG stimulation (13/29 vs. 16/29 episodes, P = nonsignificant). There was a greater density of periodic acid Schiff-positive cells ( P < 0.05) and sympathetic nerves ( P < 0.05) at the ectopic sites compared with other nonectopic atrial sites. We conclude that, in the absence of a sinus node, thoracic veins may function as subsidiary pacemakers under heightened sympathetic tone, becoming the dominant sites of initiation of focal atrial arrhythmias that arise from sites with abundant sympathetic nerves and periodic acid Schiff-positive cells.


2021 ◽  
pp. 153537022110271
Author(s):  
Yuanyuan Jia ◽  
Liuqin Xie ◽  
Zhenglong Tang ◽  
Dongxiang Wang ◽  
Yun Hu ◽  
...  

After high fractures of the mandibular condyle, the insufficient blood supply to the condyle often leads to poor bone and cartilage repair ability and poor clinical outcome. Parathyroid hormone (PTH) can promote the bone formation and mineralization of mandibular fracture, but its effects on cartilage healing after the free reduction and internal fixation of high fractures of the mandibular condyle are unknown. In this study, a rabbit model of free reduction and internal fixation of high fractures of the mandibular condyle was established, and the effects and mechanisms of PTH on condylar cartilage healing were explored. Forty-eight specific-pathogen-free (SPF) grade rabbits were randomly divided into two groups. In the experimental group, PTH was injected subcutaneously at 20 µg/kg (PTH (1–34)) every other day, and in the control group, PTH was replaced with 1 ml saline. The healing cartilages were assessed at postoperative days 7, 14, 21, and 28. Observation of gross specimens, hematoxylin eosin staining and Safranin O/fast green staining found that every-other-day subcutaneous injection of PTH at 20 µg/kg promoted healing of condylar cartilage and subchondral osteogenesis in the fracture site. Immunohistochemistry and polymerase chain reaction showed that PTH significantly upregulated the chondrogenic genes Sox9 and Col2a1 in the cartilage fracture site within 7–21 postoperative days in the experimental group than those in the control group, while it downregulated the cartilage inflammation gene matrix metalloproteinase-13 and chondrocyte terminal differentiation gene ColX. In summary, exogenous PTH can stimulate the formation of cartilage matrix by triggering Sox9 expression at the early stage of cartilage healing, and it provides a potential therapeutic protocol for high fractures of the mandibular condyle.


Author(s):  
V. Kaminskyy ◽  
L. Kovalchuk

Introduction. Finding of biological markers of genetic predisposition to the formation of glomerulonephritis (GN) will promote prediction the probability of its development still at an early stage and provide the growth of preventive direction of medicine. The purpose of the study is to evaluate the risk of GN development by antigens of AB0 and rhesus (Rh) blood groups. Materials and methods. The study included 434patients with GN(242M, 192F, aged 37.56 ± 13.01y). 1428 healthy persons was surveyed to determine the distribution of phenotypes of AB0 and Rh blood groups in the population. Results. The total value of the relative risk of GN development in all Rh–negative carriers ABprevailed by 2.34 times in the same Rh–positive. The total value of the relative risk of disease appearance in Rh–negative individuals prevailed in the same Rh–positive according to gender: in men with A and AB – 6.43 and 4.16 times, respectively, in women with B and AB – 9.34 and 2.15 times, respectively. In all patients, the common feature was a high chance of getting sick by GN in carriers phenotype AB Rh– versus 0 Rh–. Conclusions. The sex dimorphism of hereditary predisposition markers for GN is proved: men with phenotypes A Rh– and AB Rh–, women with B Rh–, AB Rh– and AB Rh+ have high risk to be ill. The persons of both sexes with phenotype 0 Rh–, as well as men with B Rh– and women with A Rh– and B Rh+ may be resistant to disease.


2021 ◽  
Vol 11 (5) ◽  
pp. 74-81
Author(s):  
Ayushi Rajkumar Jain ◽  
Doss Prakash ◽  
Sheetal Swamy

The alarming statistics of COVID-19 surges up in 2021 throwing an enormous burden on the healthcare system across the world. According to WHO reports on 14th April 2021, globally 136,996,364 confirmed COVID-19 cases are reported across the continents, including 2,951,832 deaths. The state of Maharashtra reported the maximum number of cases of India including high mortality rate. This study was conducted to identify and describe the relation of different predictors (Age, gender, duration of hospital stay, presence of co morbidities) of mortality among the COVID-19 deceased patients by retrospectively analyzing the medical case records of 121 patients from a dedicated COVID hospital at Aurangabad from July 2020 to December 2020. Chi-square test was performed to assess the association between causes of death with different cluster of variables and their significance. This study helps us to identify risk factors that show association between various predictors and mortality rate in COVID-19 patients. Out of 121 deaths, 96 (79%) were male, 61 (49.6%) were in age group between 60-79 years, ARDS was one of the major complication in the deceased patients accounting 29.8% and cardio respiratory arrest was the common cause of death among the deceased patients with 85%. It was also observed that mortality rate was very higher in the initial five days of hospitalization with critical care support. Our result findings provide clinical inferences for physicians to identify high-risk factors with COVID-19 at a very early stage. Key words: COVID-19, Mortality rate, Demographic predictors, Co-morbidities, Cardio respiratory arrest.


Author(s):  
Samir Medjekal ◽  
Mouloud Ghadbane

Sheep have a gastrointestinal tract similar to that of other ruminants. Their stomach is made up of four digestive organs: the rumen, the reticulum, the omasum and the abomasum. The rumen plays a role in storing ingested foods, which are fermented by a complex anaerobic rumen microbiota population with different types of interactions, positive or negative, that can occur between their microbial populations. Sheep feeding is largely based on the use of natural or cultivated fodder, which is exploited in green by grazing during the growth period of the grass and in the form of fodder preserved during the winter period. Ruminant foods are essentially of plant origin, and their constituents belong to two types of structures: intracellular constituents and cell wall components. Cellular carbohydrates play a role of metabolites or energy reserves; soluble carbohydrates account for less than 10% dry matter (DM) of foods. The plant cell wall is multi-layered and consists of primary wall and secondary wall. Fundamentally, the walls are deposited at an early stage of growth. A central blade forms the common boundary layer between two adjacent cells and occupies the location of the cell plate. Most of the plant cell walls consist of polysaccharides (cellulose, hemicellulose and pectic substances) and lignin, these constituents being highly polymerized, as well as proteins and tannins.


2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
J Melka ◽  
A Helbert ◽  
L Lesage ◽  
K Moreau ◽  
K Romariz ◽  
...  

Abstract Introduction Sudden death secondary to ventricular arrhythmias is common in HF patients, with no effective treatment available outside of implantable cardiac defibrillators. While animal models are essential for the discovery of anti-arrhythmic drugs, no reliable large animal HF models with associated ventricular arrhythmias have been described so far. Objectives We aimed at evaluating ventricular remodeling and arrhythmia susceptibility in an HF pig model with reduced ejection fraction (EF) following myocardial infarction (MI). Methods MI was induced in 53 male Göttingen minipigs (12–15 months, 20–25 kg) by coronary embolization in mid-left anterior descending and mid-left circumflex coronary arteries using endovascular coils. Seven other pigs underwent sham operation and were used as control. Two weeks after surgery, cardiac function was assessed by echocardiography, and animals were included based on EF&lt;50% (n=15/53), assigned either to 12 weeks of vehicle (n=9) or perindopril (n=6, 1 mg/kg/d, per os) group. At the end of the study, their left ventricular (LV) electrical remodeling was studied by echocardiography/electrocardiography and a programmed-electrical stimulation protocol was performed to evaluate the susceptibility to develop ventricular arrhythmias. Results At the end of the study, animals in the vehicle group had a significant LV remodeling associated with a reduced EF (p&lt;0.05 vs. sham, see table). This remodeling was associated with cardio-pulmonary congestion, significant increases in LV end-diastolic pressure, left atrial volume, and lung mass (all p&lt;0.05 vs. sham, see table), fully prevented by perindopril treatment. They had also an electrical remodeling as evidenced by an increase in PR, QRS, and QTc intervals, as well as LV effective refractory period (+18%, 14%, 33%, and 13%, respectively, p&lt;0.05, compared to sham animals). Electrical changes were mitigated by perindopril treatment (p=NS vs. sham). LV mechanical dispersion measured with speckle-tracking echocardiography was significantly increased in vehicle group (58±5 vs. 22±1 ms in sham group, respectively) as well as in perindopril group. Programmed-electrical stimulations induced in 6/8 vehicle animals either non-sustained (n=3) or sustained (n=2) ventricular tachycardia, or ventricular fibrillation (n=1). In sham group only 1/7 animal had a ventricular fibrillation. No inducible ventricular arrhythmia was observed in animals treated with Perindopril. Conclusion In this new pig model of congestive HF with reduced EF, LV remodeling was associated with electrical remodeling and susceptibility to develop arrhythmias. Chronic angiotensin-converting enzyme inhibitor treatment prevented congestion, mitigated electrical remodeling, and suppressed arrhythmia susceptibility. FUNDunding Acknowledgement Type of funding sources: Private company. Main funding source(s): Servier Research Institute - CardioVascular & Metabolic Diseases Center for Therapeutic Innovation Table 1


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Xin’ai Wu ◽  
Jianbo Li ◽  
Cheng Wang ◽  
Guojian Zhang ◽  
Na Zheng ◽  
...  

Primary hepatic carcinoma (PHC) is the one of the most common tumors and the common cause of cancer death in the world. Detecting PHC in its early stage by imaging methods may greatly increase survival rates of patients. Ultrasound, computed tomography, magnetic resonance imaging, and positron emission tomography/computed tomography are common imaging methods in the diagnosis of PHC. In this paper, the application of different imaging methods in diagnosing the primary hepatic carcinoma will be discussed.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
M Kobara ◽  
N Naseratun ◽  
Y Watanabe ◽  
H Toba ◽  
T Nakata

Abstract Background Myocardial infarction (MI) is a major cause of death in western countries and Japan, and hypertension is a major risk factor of MI. In hypertensive heart, acute myocardial infarction often leads to lethal ventricular arrhythmia. Nicorandil, an ATP sensitive potassium channel (KATP) opener, is usually used in the treatment of acute myocardial infarction. The effects of nicorandil on ischemic myocyte are fully defined. On the other hand, KATP in neuroterminals is known to regulate norepinephrine release, but the effect of nicorandil on ischemic norepinephrine release in cardiac tissue has remained unexplored. Purpose We examined whether nicorandil suppressed norepinephrine release via neuronal KATP and ventricular arrhythmia during acute ischemia in pressure overload-induced hypertrophic hearts. Methods SD Rats were divided into two groups; abdominal aortic constriction (AAC) group and sham-operated (Sham) group. Four weeks after constriction, cardiac geometry and function were examined using echocardiography. Then, myocardial ischemia was induced by the left anterior descending artery occlusion for 100 minutes in the presence or absence of intravenous infusion of nicorandil. Cardiac interstitial norepinephrine concentration in ischemic region was measured using the microdialysis method and concentration of cyclic AMP, a second messenger of norepinephrine, in cardiac tissue was measured by ELISA. Ventricular arrhythmias were monitered by ECG during whole ischemic period. Results Four weeks after constriction, remarkable left ventricular wall thickening was observed in AAC group. Before ischemia, ventricular arrhythmia was not found in both groups. Number of ventricular arrhythmia, including ventricular tachycardia and ventricular fibrillation, was increased in early ischemic period (- 40 min) in both groups, and was grater in AAC group. Before ischemia, interstitial norepinephrine concentration in cardiac tissue was higher level in AAC group than in Sham group. Ischemia obviously increased norepinephrine concentration in both groups time dependently and AAC further increased norepinephrine than Sham group. Concentration of cyclic AMP in cardiac tissue was raised in early ischemic period (- 40 min) and then gradually decreased. Nicorandil significantly suppressed the number of ventricular arrhythmias, and abolished the ventricular tachycardia and fibrillation without hemodynamic alterations. Nicorandil also attenuated norepinephrine and cAMP enhancement in acute ischemic period in both groups. Conclusion Ischemia-induced ventricular arrhythmia was more frequent and severe in hypertrophic hearts and interstitial norepinephrine enhancement may play a role in this ischemic arrhythmia. Nicorandil suppressed ischemia-induced interstitial norepinephrine release by neuronal KATP opening, which attenuated ventricular arrhythmias in normal and hypertrophic hearts.


1981 ◽  
Vol 240 (4) ◽  
pp. H650-H658 ◽  
Author(s):  
E. Tomomatsu ◽  
K. Nishi

Effects of electrical stimulation of sympathetic nerves to the carotid sinus on the discharge of single active baroreceptor fibers of the rabbit were examined in situ and in functionally isolated carotid sinus preparations with an intact sympathetic innervation under controlled conditions of pressure and temperature. Among 30 single units, 18 units responded to sympathetic stimulation of increasing discharge frequency. The excitatory effect of sympathetic stimulation on baroreceptor activity was not abolished by phentolamine (1 mg/kg iv or 10(-6) g/ml in perfusate). In isolated carotid sinus preparations perfused with Krebs-Henseleit solution, various pressure steps were applied to the sinus, and effects of norepinephrine (NE; 10(-9) and 10(-6) g/ml) on activity of nine single baroreceptor units were examined. In the presence of 10(-9) g/ml NE, discharge frequency of all units significantly increased at a given pressure step when compared with the control, whereas NE at a high concentration (10(-6) g/ml) did not produce significant changes in the discharge frequency. It is concluded that NE released by sympathetic nerve endings most likely acts directly on the baroreceptor nerve endings and sensitizes them.


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