The heart regulates the blood pressure in such a way that it does no harm to the organs: The heart works not like a single pump, but like two adjacent pumps, each of which has its own ventricle and atrium. This separation also divides our circulatory system into two. The right side of the heart sends blood with a relatively lower pressure to the lungs and the left side pumps blood with a higher pressure to the whole body. This pressure regulation is very important, because if the blood sent to the lungs were pumped with the same pressure as the blood sent out around the body; the lungs would be crushed, being unable to stand this pressure. The perfect balance in the heart does not permit such a problem to occur in the lungs, because the heart is flawlessly designed. SUBHAANALLAH!