CNP causes receptor-mediated positive dromotropic effects in anesthetized dog hearts

1998 ◽  
Vol 275 (2) ◽  
pp. H717-H720 ◽  
Author(s):  
Masamichi Hirose ◽  
Yasuyuki Furukawa ◽  
Yusuke Miyashita ◽  
Fumio Kurogouchi ◽  
Koichi Nakajima ◽  
...  
Keyword(s):  
Blood Flow ◽  
Coronary Artery ◽  
Natriuretic Peptide ◽  
Flow Rate ◽  
Blood Flow Rate ◽  
Natriuretic Peptide Receptor ◽  
Artery Blood Flow ◽  
Peptide Receptor ◽  
Av Conduction ◽  
Anesthetized Dogs

No data are available for the direct effect of C-type natriuretic peptide (CNP) on atrioventricular (AV) conduction in mammalian hearts. Thus we studied the dromotropic effects of CNP-22 injected into the AV node artery in autonomically decentralized hearts in open-chest, anesthetized dogs. CNP decreased AV interval (AV conduction time) in a dose-dependent manner with increase in coronary artery blood flow rate in six anesthetized dogs. Isosorbide dinitrate did not affect AV interval, but it increased coronary artery blood flow rate. A guanylyl cyclase-linked natriuretic peptide receptor antagonist, HS-142–1, inhibited the decreases in AV interval and the increases in coronary blood flow rate in response to CNP, whereas propranolol did not affect the positive dromotropic response to CNP. These results demonstrate that CNP decreases AV interval and increases coronary artery blood flow rate mediated by a guanylyl cyclase-linked natriuretic peptide receptor, but not β-adrenoceptor, in the dog heart.

scholarly journals Integrating Patient-Specific Electrocardiogram Signals and Image-Based Computational Fluid Dynamics Method to Analyze Coronary Blood Flow in Patients during Cardiac Arrhythmias

2019 ◽  
Vol 40 (2) ◽  
pp. 264-272
Author(s):  
Szu-Hsien Chou ◽  
Kuan-Yu Lin ◽  
Zhen-Ye Chen ◽  
Chun-Jung Juan ◽  
Chien-Yi Ho ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Blood Flow ◽  
Coronary Artery ◽  
Cardiac Arrhythmia ◽  
Coronary Arteries ◽  
Flow Rate ◽  
Blood Flow Rate ◽  
Patient Specific ◽  
Ecg Signals

Abstract Purpose The aim of this study was to use the computational fluid dynamics (CFD) method, patient-specific electrocardiogram (ECG) signals, and computed tomography three-dimensional image reconstruction technique to investigate the blood flow in coronary arteries during cardiac arrhythmia. Methods Two patients with premature ventricular contraction-type cardiac arrhythmia and one with atrial fibrillation-type cardiac arrhythmia were investigated. The inlet velocity of the coronary artery in simulation was applied with the measured velocity profile of the left ventricular outflow tract (LVOT) from the Doppler echocardiography. The measured patient central aortic blood pressure waveform was employed for the coronary artery outlet in simulation. The no-slip boundary condition was applied to the arterial wall. Results For the patient with irregular cardiac rhythms (Case I), the coronary blood flow rate under the shortened and lengthened cardiac rhythms were 0.66 and 0.96 mL/s, respectively. In Case II, the maximum velocity at the LVOT under a normal heartbeat was found to be 101 cm/s, whereas the average value was 73 cm/s. In Case III, the patient was also diagnosed with a congenital stenosis problem at the myocardial bridge (MCB) at the LAD. The measured blood flow rate at the MCB of the LAD for the three heartbeats in Case III was found to be 0.68, 1.08, and 1.14 mL/s. Conclusion The integration of patient-specific ECG signals and image-based CFD methods can clearly analyze hemodynamic information for patients during cardiac arrhythmia. The cardiac arrhythmia can reduce the blood flow in the coronary arteries.

scholarly journals Feasibility of MRI to assess differences in ophthalmic artery blood flow rate in normal tension glaucoma and healthy controls

2020 ◽  
Author(s):  
Martin Kristiansen ◽  
Christina Lindén ◽  
Sara Qvarlander ◽  
Anders Wåhlin ◽  
Khalid Ambarki ◽  
...  
Keyword(s):  
Blood Flow ◽  
Flow Rate ◽  
Ophthalmic Artery ◽  
Blood Flow Rate ◽  
Normal Tension Glaucoma ◽  
Healthy Controls ◽  
Artery Blood Flow

scholarly journals Why Does Vascular Access Dysfunction Occur despite Brachial Artery Blood Flow Being Higher than Preset Blood Flow?

2022 ◽  
Vol 2 (1) ◽  
pp. 38-43
Author(s):  
Jun-ichi Ono ◽  
Takushi Oiwa ◽  
Yasuo Ogasawara ◽  
Seiichi Mochizuki
Keyword(s):  
Blood Flow ◽  
Flow Rate ◽  
Vascular Access ◽  
Brachial Artery ◽  
Pure Water ◽  
Blood Flow Rate ◽  
Path Model ◽  
Artery Blood Flow ◽  
Recirculation Rate ◽  
Model Fluid

Background: In recent years, many reports have investigated the usefulness of brachial artery blood flow (BAF) measured by ultrasonography as an evaluation index for the vascular access (VA) stenosis of hemodialysis patients. However, the mechanism of VA dysfunction, despite BAF being higher than the preset blood flow, has not been clarified to date. Methods: The relationship between actual blood-removal flow and recirculation rate with decreasing VA flow was examined using a VA flow path model and pure water as a model fluid. The blood-flow rate was set at 180 mL/min, and the set VA flow rate was lowered stepwise from 350 to 50 mL/min. VA flow rate, blood-removal flow rate, and flow waveform measured between two needle-puncture sites were recorded, and then the actual blood-removal flow rate and recirculation rate were calculated. Results: Recirculation was observed at a VA flow rate < 300 mL/min. The recirculation was due to the VA flow rate, which was transiently reduced to the level below the blood-removal flow rate, resulting in backflow. In contrast, no decrease in the actual blood-removal flow rate was observed. Conclusion: It is suggested that the mechanism of the VA dysfunction, despite the BAF being higher than the preset blood-flow rate, was due to the diastolic BAF being lower than the blood-removal flow rate.

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