afterload

(redirected from after-load)

afterload

 [af´ter-lōd]
the tension developed by the heart during contraction; it is an important determinant of myocardial energy consumption, as it represents the resistance against which the ventricle must pump and indicates how much effort the ventricles must put forth to force blood into the systemic circulation. Factors that increase afterload include aortic and pulmonarystenosis, systemic and pulmonary hypertension, and high peripheral resistance.

af·ter·load

(af'ter-lōd),
1. The arrangement of a muscle so that, in shortening, it lifts a weight from an adjustable support or otherwise does work against a constant opposing force to which it is not exposed at rest.
2. The load or force thus encountered in shortening.

Afterload

Cardiology The amount of haemodynamic pressure (peripheral vascular resistance) downstream from the heart, which increased in heart failure secondary to aortic stenosis and hypertension. Cf Preload.
Physiology The tension produced by heart muscle after contraction.

afterload

Cardiology The amount of hemodynamic pressure–peripheral vascular resistance downstream from the heart–which ↑ in heart failure 2º to aortic stenosis and HTN. Cf Preload Physiology The tension produced by heart muscle after contraction.

af·ter·load

, after-load (af'tĕr-lōd)
1. The arrangement of a muscle so that, in shortening, it creates a force from an adjustable support or otherwise work against an opposing force to which it is not exposed at rest.
2. The load or force thus encountered in shortening.
3. That resistance against which the left ventricle must eject its volume of blood during contraction.
References in periodicals archive ?
Systemic arterial flow is regulated by complex factors: cardiac output, preload blood flow, after-load including peripheral vessel resistance, arterial elasticity, and others.
LV dysfunction can occur in ASO due to two reasons firstly because of overfilling or increase in after-load and secondly due to myocardial ischaemia secondary to reduced or obstructed flow through re-implanted coronaries.
The mechanism for hypotension and shock in sepsis are: reduced pre-load, myocardial suppression as well as reduced after-load contributing to hyperdynamic but insufficient cardiac function resulting in tachycardia and hypotension.
The increased after-load might contribute to the decreased CO.
The regulation of SV is dependent, inter-alia, on cardiac pre-load and after-load. In healthy, young, populations, after-load may not be a major determinant in altering SV, because after-load is dependent on aortic elasticity, which under normal circumstances should not be compromised since aortic compliance and cross sectional area increases with increasing pressures.8 With ageing, aortic elastic fibers may lose elasticity and atherosclerosis can result in aortic rigidity.9 WEU volunteers were young and healthy; hence possibility of dysregulation in after-load is unlikely.
The increased myocardial wall tension (increased after-load) causes left ventricular diastolic dysfunction, which further elevates pulmonary artery and pulmonary capillary pressures.
A useful way of describing the problem is to consider the patient's journey, using the analogy of the cardiac cycle and the concepts of pre-load, contractility and after-load. These three components represent the areas that contribute to ED overcrowding and, in keeping with the cardiac analogy, often result in cardiac failure.
A second mechanism of action involves the opening of ATP-dependent potassium channels in vascular smooth muscle, resulting in reduced preload and after-load due to arterial and venous dilation, Dr.