在实验性急性右心室压力负荷期间大动脉收缩的影响. 进一步了解透析和静脉心室相互作用的进一步见解
I Belenkie1, S G Horne, R Dani
1Department of Medicine, Faculty of Medicine, University of Calgary, Alberta, Canada.
Circulation
|August 1, 1995
概括
大动脉收缩通过改变心室相互作用,而不是通过增加冠状动脉血流来改善急性右心室高血压期间的心脏功能. 这一发现强调了机械影响对流动动力学在管理RV高血压方面的重要性.
科学领域:
- 心血管生理学心血管生理学
- 血液动力学 血液动力学
- 室腔相互作用 室腔相互作用
背景情况:
- 急性右心室 (RV) 高血压可能导致血液动力学崩.
- 减少RV输出和不良心室相互作用有助于减少左心室 (LV) 末缩体积.
- 众所周知,大动脉收缩在这种情况下可以改善心脏功能,通常归因于冠状动脉输液的增加.
研究的目的:
- 调查改变心室相互作用的假设,特别是隔膜力学,有助于RV高血压期间大动脉收缩的有益影响.
- 为了区分改变的腹腔相互作用与冠状动脉 perfusion 改变对心脏功能的影响.
主要方法:
- 在九只狗中使用了超声波尺寸晶体和导管尖端的压力计,以测量RV和LV的尺寸和压力.
- 使用充气袖子监测心周压和肺动脉 (PA) 和大动脉收缩.
- 独立 perfused 右冠状动脉 (RCA) 控制和测量冠状动脉血流.
主要成果:
- 严重的PA收缩减少了RV中风体积,随着同时发生的大动脉收缩而改善,独立于RCA流量的显著变化.
- 大动脉收缩引发了扩张和收缩心室相互作用的显著变化,其特点是增加横隔膜压力梯度和向右隔膜转移.
- 增加RCA压力到大动脉压力水平提高了RCA流量,但没有改善RV功能,表明冠状动脉流量不是主要有益的因素.
结论:
- 大动脉收缩改善了急性RV高血压中的心脏功能障碍,主要是通过心室相互作用的机械改变,独立于右冠状动脉流量的变化.
- 当冠状动脉压力保持在正常或增加水平时,冠状动脉流量的变化不会显著影响心脏功能的观察到的改善.
相关概念视频
Mitral Regurgitation I: Introduction
Mitral regurgitation is characterized by the backward circulation of blood from the left ventricle to the left atrium during systole, a phase of the cardiac cycle when the heart contracts and pumps blood out of the chambers. This abnormal flow occurs primarily due to the dysfunction of the mitral valve or its supporting structures, which include the mitral leaflets, chordae tendineae, annulus, and papillary muscles.Etiology and Mechanisms:Primary Mitral Regurgitation: This type arises from...
Aortic Regurgitation I: Introduction
IntroductionAortic regurgitation is characterized by the backward flow of blood from the aorta into the left ventricle during diastole and arises from the improper closure of the aortic valve. This condition results in left ventricular volume overload and can stem from both acute and chronic etiologies, each contributing uniquely to the disease's progression and symptomatology.Acute and Chronic CausesAcute aortic regurgitation often results from events that suddenly impair the integrity of the...
Aortic Regurgitation II: Clinical Features and Diagnostic Tests
Aortic valve regurgitation (AR) occurs when the aortic valve fails to close properly, allowing blood to flow backward from the aorta into the left ventricle. This backflow can result in two distinct clinical presentations: acute and chronic AR, each characterized by its own set of symptoms and physical findings.Acute Aortic RegurgitationAcute AR presents with a sudden onset of severe symptoms. Patients typically experience profound dyspnea (shortness of breath), chest pain, and signs of left...


