🤍 Medical Student

When the impulse reaches another special area of the heart , right in the center of the septum konwas Atrio-Ventricular (or AV) Node The impulse is delayed for approximately 0.2

(SAN) this is the heart's natural pace maker

Specialized cells in the right atrium called the sino-Atrial Node (SAN)

The AV Node relays the electrical impulse down the septum along the Bundle of Hiss to the base of the ventricles

The vagus nerve of the parasympathetic nervous system decreases heart rate

Accelerator of the sympathatic nervous system increase heart rate

The autonomic nervous system controls heart rate

Heart is unlike other muscles ,it doesn't rquire anew nerve impulse for each contraction

During exercise that can increase to as many as 200 beats per minute for athlete

For rest of us 150 b.p.m.is about all wecan safely manage

Cardiac muscle can respire anaerobically and so the muscle cannot get tired

The heart can be thought as three pumps sitting side by side

Our heart beats over 2.5 million times in an average life span

The heart can not generate its own electrical rhythm myogenic

Septum Prevents the mixing of oxygenated (right side) and deoxygenated (left side) blood

The cardiac cycle is the sequence of events in many heartbeats

If any of the valves do not close properly An extra sound called a heart murmur 🤣😂 My be heard

Sound that caused by the snapping shut of the Aortic Pulmonary