The valves of the heart. They're one way valves that won't allow blood to flow back into the heart, provided the heart and valves are normal.
In some cases, the valves can be defective, and cause the exact 'backflow' you're asking about. These cases are rare.
There are valves in the heart - and the larger blood vessels that stop the blood flowing backwards.
Valves prevent the backflow of blood, in this case the semilunar valves stop blood flowing back into the heart.
The veins return blood from the body back to the heart, then out of the heart to the lungs where it is oxygenated, then back to the heart and carried back out into the body by arteries. The blood in the veins is blue but is seen through you skin as a dark green.
the stop of blood flow to the heart
As long as it is being pumped, blood will circulate - unless obstructed in the arteries and veins. This means stopping blood circulation requires stopping the heart (such as happens when you die or otherwise go into cardiac arrest) or introducing a major clot to block the blood flow. Circulation also can stop if the heart goes into fibrillation - rapid, irregular, and unsynchronized contraction of the heart muscle fibers. The heart just kind of quivers instead of pumping blood. Probably blood circulation would also stop if you bled so much that there was no blood left to circulate - but at that point the heart would probably stop pumping to so it still goes back to stopping the heart.
No. Only if you have a heart condition and time to contemplate your predicament.
2 of these valves (one on each side) stop blood from flowing back into the atria chambers of the heart when the heart is contracting and expelling blood. The other two are there to stop blood flowing out of the ventricles when the heart is filling up with blood. One stops blood flowing through the aorta to supply the body and the other stops it flowing through the pulmonary artery to the lungs.
Before it goes back to your heart is gives oxygen to your skin and organs to keep them running. If they don't get oxygen they can stop working.
Heart.
The valves in the veins & arteries stop the blood flowing back along with the heart pumping & thus pushing the blood around the body. The inter-atrial & interventrical septum's separate the for chambers of the heart.
if the heart stops
valves