1. The cardiovascular system
The transport system of human body i.e. cardiovascular system comprises of heart and as a pump of system it conveys blood to different parts of body through blood vessels. So the delivery routes of cardiovascular system are vessels which carry fluid, the blood containing necessary nutrients and gases like oxygen that body needs and it also carry wastes such as carbon dioxide. Exact location of heart is between the lungs having an outer layer pericardium. There are coverings superior vana cava and the pulmonary arteries and veins [1]. The main physiology of heat is showed in this figure.
The heart is divided into left and right parts which are further comprised of chambers. Atria consist of upper portion and lower portion is by ventricles. Upper chambers receive blood from body and then provide to lower chambers. The lower chambers have the function to provide blood to whole body. At high pressure the arteries which convey blood from heart to body have elastic walls, receive blood and convey it to the whole body. So they are divided into branches of different sizes so blood enters through thin and small capillaries. These capillaries are permeable to nutrients and wastes. In capillaries blood carries droplets of oxygen and waste products move slowly at low pressure and moved to venules which smaller veins are forming structures that lead to heart [2].
Largest artery is aorta which get blood from left ventricle and from right ventricle blood go through pulmonary trunk. Except pulmonary veins which get blood from lungs and provide to left atrium, other veins move to inferior or superior vana cava. There are so many flaps in heart chambers and vessels, theses valves are just like gates open at specific correct signal for blood flow as well as closed. There are specified arties and veins for all organs like hepatic arteries provide blood to liver, renal for kidneys and so named in accordance to that specific organ [3].
Blood is responsible to provide oxygen to whole body, act as a messenger. It is responsible for acid base balance in body. It consists of liquid and suspended particles which include proteins and salts etc. Liquid part is plasma and it contain water, protein, ions and waste materials. Red blood cells have haemoglobin and carry oxygen due to presence of iron in haemoglobin protein. The red protein haemoglobin provides oxygen to body by binding to Fe. RBCs have total life span of 120 days after that they are destroyed by macrophages are removed through spleen. White blood cells are involved in immune system and protect body against foreign particles. Platelets are responsible for blood clotting as they have blood clotting factors involved for clotting purpose. Hematopoietic stem cells continuously divide in a life period of a human and give rise to new blood cells that replace old and worn-out cells which have fate to be destroyed and engulfed by macrophages [2].
Blood deficiency cause anaemia and it is due to diseases related to iron deficiency and other useful minerals. Vitamin K is responsible for clotting of blood, so any harm to it can cause anti coagulation activities of blood which are responsible for anaemia. Haemolysis due to medications or some environmental factors also lower blood quantity. Leukaemia is related to abnormality in bone marrow cells which produce White blood cells [1].
In a normal person, heart beats 70 to 80 times at rest stage, beat can be heard through stethoscope and it is “lubb-dupp” voice. In a complete heart beat there is one cardiac cycle as pumping of heart at contraction is systolic and at relaxation is diastole. Cardiac cycle starts at relaxation in diastolic form and receive blood from body then it starts to contract, the right and left atria convey blood to their respective ventricles. After that blood goes to aorta and pulmonary trunk in relax phase. At this time ventricles are in relax phase to avoid backward movement of blood and then get diastolic pressure so this cycle goes on. Abnormal systolic and diastolic pressures give rise to blood pressure issues that can lead to brain stroke or heart failure. So, because of cardiovascular system body is able to get oxygen for performing normal functions and get rid of harmful gases [4].
2. Electrophysiology
To check electrical properties of different tissues of the body electrophysiology is used. Actually it measures voltage change so it is related to electrical signals. In neurons it is used for large scale electrical signals [5].
Heart beats just because of electrical signals of right atrium generated naturally in body. The contraction of heart does a beat and then provides blood to whole body. Certain diseases like high blood pressure, fatigue and heart attacks lead to dis functioning of heart like slowing of beats i.e. arrhythmias, then electrophysiology comes to see heart very accurately, actually it is a diagnostic tool [3]. It is used to determine cause and treatment of heart dysfunction. Atrial fibrillation is cause of irregular heartbeat. Finding cause of arrhythmias is necessary for a Physician who has to suggest treatment for related cause.
All rhythms of heart are accurately found in dark so, for electrophysiology patient is kept in darker room for better diagnosis. In darker room patient lay down on bed padded with X-ray and medication is done through IV. The purpose of this medication is to make patient relax and more alert or active. To numb the skin local anaesthesia is provided and groin or neck area at which slow beat is found have been cleaned with antibacterial wash. Patient is linked to a small sheath; a tub like structure, although heart is guided up with small catheters which are used to record arrhythmia beats. Catheters are small electrodes which sense electric current. Fluoroscopic X-ray is used to detect various locations in heart and accuracy of catheters to find exact results. Image on screen are shown so this is a cardiac mapping. Whole process takes1to 4 hours for accurate findings. The patient does not feel presence of catheters because absence of sensory nerve endings in heart veins or arteries. When it is done then catheters are removed body and at insertion side some pressure is applied to be safe from bleeding. If electrophysiology finds exact location and type of abnormal heartbeat, then immediately treatment is done through pacemaker or with some medications [5, 6].
Once it is done one should take some rest and avoid driving for next whole day. Puncture side may get some infections or get sore so press it or use some medication. After or before electrophysiology, patient feels dizziness so electric shock is provided to regulate heartbeat. To avoid from clotting at insertion site by catheter patient is provided with proper care or after clotting medicine is given to him. These results from electrophysiology provide diagnosis about diseased condition so that doctor decides to treat with medicine or through a pacemaker or some sort of surgery [6].
3. Pacemaker
The normal heartbeat comes from a group of cells which are pacemakers that generates electric signal which is responsible for contraction of heart that lead to produce a heartbeat. Hear beat is produced after completion of one cardiac cycle. A normal person should have normal heart beat that is about 80 times in a second. Low or higher than normal heart beat rate lead to bradycardia or tachycardia respectively.
Electric changes can be recorded through electrocardiogram on a moving graph paper [5].
People may need artificial pacemaker for diseases as aging can disrupt heartbeat, cardiac abrasions, medications, high blood pressure and smoking can cause arrhythmia; the irregular heartbeat. If it senses that heart beat is missed and beat is slow as in bradycardia or heartbeat is fast as in tachycardia then it works to send signals at a steady rate. It consists of a generator which contains small battery affiliated with electric circuit to regulate electric pulse and wires or cables for each chamber to deliver pulse. These wires are fabricated, having elasticity and good conducting. It is fixed under the skin in chest area to manage heart rate temporarily. In heart failure they are fixed permanently [7].
There are many types of pacemakers i.e. single, dual and biventricular. Single pacemaker is responsible for transferring electrical impulse from generator to single heart chambers which is left ventricle. Although dual pacemaker transfer electric pulse to both chambers which are right atrium and left ventricle. For persons having heart failure, biventricular pacemaker has been used. As biventricular pacemaker provide electrical impulse to both lower chambers of heart. It increases efficiency of heart. To fix a pacemaker is easy as it don’t want open heart surgery [6].
Before fixing of pacemaker some tests are done to check electrophysiology. Surgery is done to implant artificial pacemaker and for this patient is get ready in his awake stage with some local anaesthesia to numb the skin. Intravenous medication is given to relax the patient in X-ray equipped room to get clear picture. Flexible and insulated wires are implanted in major vein near collarbone and detection is done by X-ray fluorescent. Pulse generator is attached at one end of wire and other end is inserted in heart [5].
During fixing the pacemaker its image is showed on a graph paper which predicts accuracy of insertion of pacemaker the body. If it starts to work than normal electrocardiogram is produced, and this ECG is done to check normal heart rate. After fixing pacemaker patient should have to rest for some days and should avoid contacting any electric device directly to chest area as it results in sudden fatigue. After getting pacemaker patient have to get normal diet and avoid from too much electrolytes consumption.
Through direct contact to electric circuits or phone cells false signalling can be produced.
Once your pacemaker is implanted, the battery should last five to 15 years, which is the average battery life time. After fixation patient should have to get his check up and meet up with physician by routine. When a pacemaker’s battery is going to its end after completion of its life span then pulse generator part is replaced. The wires of that pacemaker remain there, although thy can be replaced properly. To change pacemaker there are many easiest and quick ways which requires less retrieval time than it was used to fix very first time. It’s up to a patient of heart related disease that if get proper instructions and took care of artificial pacemaker then it provide more long-time viability [5].
Artificial pacemakers provide standard treatment to diseases which are responsible for disturbances in electrical signals to heart. As heart is vital organ of body so any harm to it ultimately cause death. Pacemakers are new technology and provide lifesaving impacts. They are specifically used to prevent lowering of heart beats and its related abnormalities like fatigue, fainting and dizziness. They actually resume life and provide physical activities with more power as a normal one [8].
There are some interesting facts related to use of pacemaker that if a person having artificial pacemaker get some diseased condition like cancer then pacemaker make life duration long for that person. It provides more safety to life than was normal. Once a pacemaker has been turned off it can lead to death. More about this is under research [7, 8].