Author Archives: Website Unit

The natural sinus rhythm of the heart that gives a resting heart rate is affected by several factors. The cardiovascular centers in the brainstem control the sympathetic and parasympathetic effects… Read more »

The normal resting heart rate is called the cardiac rhythm and is made in the sinoatrial node, a group of pacemaker cells found in the wall of the right atrium…. Read more »

The normal rhythmic heartbeat is called the sinus rhythm, and it is released from the sinoatrial node from pacemaker cells. In this node, an electrical signal is made that travels… Read more »

Cardiac output (CO) is a measure of the amount of blood each ventricle pumps (the stroke volume) in one minute. Heart output is calculated by multiplying the stroke volume (SV)… Read more »

The term cardiac cycle refers to a complete heartbeat that includes systole, diastole, and pause.[11] The cycle begins with the contraction of the atria and ends with the relaxation of… Read more »

The function of the heart is to act as a blood pump for the circulatory system, providing continuous blood flow to the entire body. This circulation consists of systemic circulation… Read more »

The heart receives nerve signals from the vagus nerve and from nerves emanating from the sympathetic trunk. These actions influence, but do not control, the heart rate. Sympathetic nerves also… Read more »

Heart tissue, like all tissues in the body, needs a supply of oxygen, nutrients, and a way to get rid of metabolic waste. This is achieved through the coronary circulation,… Read more »

The heart wall consists of three layers: the inner, which is the endocardium, the middle, which is the myocardium, and the outer, which is the epicardium. These three layers are… Read more »

The left heart consists of two chambers: the left atrium and the left ventricle, which are separated by the mitral valve.[9] The left atrium receives oxygenated blood returning from the… Read more »