What is a cardiac load?

Cardiac preload refers to the blood volume and pressure that the heart receives before contraction.

Cardiac preload can reflect the load that the heart receives during diastole, that is, the resistance that the heart needs to overcome from venous return. Secondly, it is mainly affected by factors such as systemic circulation blood volume, venous return velocity and venous return resistance. In clinical practice, increased cardiac preload may lead to increased cardiac dilation and filling pressure, which in turn may cause cardiac diastolic dysfunction and even congestive heart failure.

Cardiac afterload refers to the resistance that the heart needs to overcome during contraction, that is, the resistance that the heart needs to push blood to the arterial system.

Cardiac afterload is mainly affected by arterial vascular resistance and arterial elasticity and aortic blood pressure. In addition, increased cardiac afterload may lead to impaired cardiac systolic function, making it more difficult for the heart to send blood, resulting in excessive cardiac load, which is prone to myocardial ischemia and angina pectoris.