ventricular afterload

ven·tric·u·lar af·ter·load

formerly and erroneously, the arterial pressure or some other measure of the force that a ventricle must overcome while it contracts during ejection, contributed to by aortic or pulmonic artery impedance, peripheral vascular resistance, and mass and viscosity of blood; now, more rigorously expressed in terms of the wall stress, that is, the tension per unit cross-sectional area in the ventricular muscle fibers (calculated by an expansion of Laplace law using pressure, internal radius, and wall thickness) that is required to produce the intracavitary pressure required during ejection.

ven·tric·u·lar af·ter·load

(ven-trik'yū-lăr af'tĕr-lōd)
The sum total of the forces, both hemodynamic and mechanical, which the left ventricle of the heart must pump against to send oxygenated blood out into the body.
References in periodicals archive ?
Second, the possibility of impeding venous return and augmenting right ventricular afterload by high airway pressure needed to be confronted.
The sudden elevation of right ventricular pressure and consequently increased right ventricular afterload produced by pulmonary artery outflow obstruction results in right ventricular failure and dilatation inducing myocardial ischemia.
Stiffening increases left ventricular afterload and causes left ventricular hypertrophy which in turn increases myocardial oxygen demand, thus may further increase the coronary artery disease (8).
1) An acute increase in pulmonary vascular resistance will increase right ventricular afterload and can lead to right ventricular dysfunction.
Specific therapy to augment right and left ventricular contractility and reduce right ventricular afterload by means of pulmonary vasodilatation included a loading dose (50 [micro]g/kg) followed by continuous infusion of milrinone (0.
Wilmer Nichols, PhD, University of Florida College of Medicine, presented data demonstrating that EECP therapy helped reverse impaired blood vessel response and elasticity to levels that patients possessed at a younger age during his presentation, "Enhanced External Counterpulsation Decreases Wave Reflection Amplitude and Reduces Left Ventricular Afterload and Systolic Stress in Patients with Refractory Angina.
At the same time, these patients often receive (1) a positive inotrope to improve myocardial contractility, (2) an anti-hypertensive drug to reduce left ventricular afterload, and (3) a diuretic to reduce venous return and to reduce preload.
In coronary artery disease, the addition of coarctation further increases both left ventricular afterload and myocardial oxygen demand.
Volume expansion versus norepinephrine in treatment of low cardiac output complicating an acute increase in right ventricular afterload in dogs.
Asthma increasing right ventricular afterload affects pulmonary arterial pressure and systolic-diastolic activity of right ventricle indirectly (7).
And importantly, the vasodilatory action of levosimendan reduces both right and left ventricular afterload, reducing the work of each stroke volume.
The net effect of this increased muscularization and fibrosis narrowing of the vascular lumen, producing increased resistance to flow, and increasing right ventricular afterload.