Cardiology is the diagnosis and treatment of human or animal hearts In the focus of Cardiology, the heart has many different anatomical features including ventricles, atria and valves. While plenty is known about the healthy heart, Cardiology usually studies diseased hearts. Because diseases of the heart can lead to many complications and is the leading cause of death, it is important to study these diseases to try and develop new medicine or procedures to prevent heart disease from causing so many complications. The HeartThe primary job of the heart is to pump blood throughout the body.
This is accomplished through systemic circulation and pulmonary circulation. In systemic circulation, the heart pumps blood through the extremities and most of the organs of the body. Through pulmonary circulation, the heart pumps blood through the lungs. It takes the de-oxygenated blood away from the heart, to the lungs, and back to the heart with oxygen-rich blood. Because the heart is an intricate organ it has many parts that can fail due to disease or dysfunction.
The electrical portion of the heart is caused by muscle cells that are charged by the cardiac pacemaker in the sinoatrial node. These electrical charges and beats can be monitored through the use of ECG’s (electro-cardio-grams). These electrical charges propagate throughout the heart in a specific pattern. Dysfunction of these electrical currents can manifest itself in many ways including ventricular fibrillation, heart block and Wolff–Parkinson–White syndrome. The mechanical part of the heart is based off of moving blood through itself, and to the rest of the body fluently.
Just like an engine, or a pump, if the heart is not “running” properly many adverse effects can occur which can lead to heart disease. Disorders of Coronary CirculationDisorders like ACS refer to a group of symptoms attributed to obstruction of the Coronary Arteries. ACS symptoms often include chest pain, with the pain radiating to the left arm or jaw. The biggest symptom to low blood flow to the heart is chest pain, nausea and vomiting and a feeling of impending doom. Patients that are expected to have an ACS disorder are sent in to the hospital to have a various set of tests done. If complications are allowed to get worse, STEMI and non-STEMI myocardial infarctions can occur causing stoppage of the heart due to multiple reasons like low blood circulation and stoppage of the electric current in the heart.
Angina PectorisCommonly known as just Angina, this complication is due to ischemia of the heart muscle. The main cause of Angina is Coronary heart disease due to infection and inflammation of the arteries feeding the heart. In most cases Angina can be very painful for the victim. There are two types of Angina known, Stable and unstable. Stable angina is also called effort angina, this refers to a common understanding of Angina related to Myocardial Ischemia.
Typical symptoms of stable angina are that of chest discomfort associated with running, walking and other forms of exercise, with little or no symptoms at rest or with administration of Nitroglycerin. Unstable Angina, or, Crescendo Angina is a form of acute coronary syndrome. It usually occurs at rest, is very severe and occurs in a pattern. Unstable Angina may occur unpredictably at rest, which may be a serious indicator of an impending heart attack.
What differentiates stable angina from unstable angina (other than symptoms) is the pathophysiology of the atherosclerosis. The pathophysiology of unstable angina is the reduction of coronary flow due to transient platelet aggregation on apparently normal endothelium, coronary artery spasms, or coronary thrombosis. AtherosclerosisAtherosclerosis, or ASVD occurs when an artery wall thickens as a result of accumulation of calcium and fatty materials like cholesterol and triglycerides. It reduces the elasticity of the artery walls and allows less blood to travel through. Because of this, increased blood pressure is a side effect. Atherosclerosis is often asymptomatic pending grave blockage and narrowing of an artery.
Signs and symptoms usually come out when the severe blockage impedes blood flow to different organs. Most of the time, patients realize that they have the disease only when they experience other cardiovascular disorders such as stroke or heart attack. These symptoms, however, still vary depending on which artery or organ is affected Typically, atherosclerosis begins as a thin layer of white streaks on the artery wall (usually due to white blood cells) and progresses from there. Clinically, atherosclerosis is typically associated with men over the age of 45. Sub-clinically, the disease begins to appear at early childhood, and perhaps even at birth (although not proven).
Noticeable signs can begin developing at puberty. Though symptoms are rarely exhibited in children, early screening of children for cardiovascular diseases could be beneficial to both the child and his/her relatives. While coronary artery disease is more prevalent in men than women, atherosclerosis of the cerebral arteries and strokes equally affect both sexes. Coronary Heart DiseaseCoronary Heart Disease is the most common type of heart disease and the cause of many heart attacks. The disease is caused by plaque building up along the inner walls of the arteries of the heart, which narrows the arteries and reduces blood flow to the heart.
Most individuals with this disease show no signs or symptoms until a sudden “attack” takes place. There are many risk factors for heart disease including sex, age, history of heart disease, smoking and obesity. Most of the time the biggest factors determining whether or not you will have this disease depend on your diet and exercise. For those who know they have Coronary Heart Disease, they would be smart to change their lifestyle and become more active and eat better.
Also, if you are a smoker, stopping smoking will greatly lower your risk for heart attack, and taking aspirin (a blood thinner) makes it easier for the heart to pump blood and knock out small clots. Myocardial InfarctionA Myocardial Infarction is most commonly known as a heart attack. This occurs when a part of the heart dies due to having restricted blood flow, which leads to oxygen deprivation. Both Coronary heart disease and Myocardial infarction go hand in hand because a heart attack usually doesn’t occur without the presence of a disease within the heart. A person suffering from an acute MI usually have sudden chest pain with some of the following symptoms. Shortness of breath, sweating, nausea, vomiting, abnormal heartbeats, and a feeling of impending doom.
many of the risk factors for a heart attack are very preventable, and mostly have to do with living a healthier lifestyle. Smoking and obesity connect to 56% of coronary heart disease together, and lack of exercise by itself has been linked to 12% of cases. Cardiac Arrestrefers to the ceasing of normal systemic circulation due to failure in proper contraction of the heart. There are several conditions that can cause this. Normal Sinus RhythmNormal sinus rhythm is the rhythm where the heart should be beating at all times. A “normal rhythm” is considered around 60-100 beats per minute of a stable P,Q,R,S and T wave.
Asystole (flatline)Asystolic refers to the heart having no cardiac activity. This includes electrical pulses, output or blood flow. A flatline cannot be shocked because there is not rhythm to shock. The way an AED works is that it takes whatever rhythm exists and brings it back to a flatline. Although not every rhythm is shockable, CPR can bring back a shockable rhythm if properly used.
When the heart is producing a rhythm that should be producing a heartbeat but is not, this is known as pulseless electrical activity. PEA is countered by CPR and special drugs such as epinephrine and the use of a defibrillator to bring the heart back to a flatline and coax it into a normal rhythm with use of CPR. Ventricular FibrillationV-Fib or Ventricular Fibrillation is a condition where uncoordinated contractions of the heart cause no real blood to be pumped throughout the body. The ventricles in the heart quiver instead of contracting properly. V-fib is a shockable heart rhythm so medical personnel can use an AED to shock the heart, bring it to a flatline and use CPR to bring the heart back to a normal rhythm. Disorders of the MyocardiumCardiomyopathy which literally means (heart muscle disease) is any deterioration of the heart muscle which commonly leads to heart failure.
Cardiomyopathy can be acquired or inherited by genes and by your health. If you live a very healthy lifestyle but your parents or grandparents suffer from this disease there is a probability that you may inherit it. However if there is no genetic connection to this disease, but you live a very unhealthy lifestyle you also have a somewhat high chance to acquire this disease. The biggest problem with this disease is that it causes Ischemia, which is poor oxygen circulation to the heart. Because of this the heart has less oxygen to work with than needed, which causes other problems within the heart and other parts of the body.
Although there is no medication to stop or reverse this disease, pacemakers and defibrillators can help someone that suffers from having severe and sudden heart attack, but they will not work 100% of the time. Ventricular HypertrophyVentricular Hypertrophy is the thickening of the ventricular walls, the lower chambers of the heart. There are generally two types of hypertrophy consisting of healthy and unhealthy. The ventricles are the chambers in the heart responsible for pumping blood either to the lungs (right ventricle) or to the rest of the body (left ventricle). Healthy cardiac hypertrophy is the normal and healthy response to an increase in exercise, or becoming pregnant.
This allows the heart to increase in mass and also increase its pumping ability. Trained athletes have hearts that have left ventricular mass up to 60% greater than untrained subjects. Diseases of the blood vessels: AtherosclerosisAtherosclerosis is a specific form of arteriosclerosis in which an artery wall thickens as a result of the accumulation of calcium and fatty materials such as cholesterol and triglyceride. It reduces the elasticity of the artery walls and therefore allows less blood to travel through. This also increases blood pressure.
Atherosclerosis is often asymptomatic pending grave blockage and narrowing of an artery. Signs and symptoms usually come out when the severe blockage impedes blood flow to different organs. Most of the time, patients realize that they have the disease only when they experience other cardiovascular disorders such as stroke or heart attack. These symptoms, however, still vary depending on which artery or organ is affected.
Typically, atherosclerosis begins as a thin layer of white streaks on the artery wall (usually due to white blood cells) and progresses from there. Clinically, atherosclerosis is typically associated with men over the age of 45. Sub-clinically, the disease begins to appear at early childhood, and perhaps even at birth.Deep Vein ThrombosisDeep Vein Thrombosis is the formation of a blood clot inside a deep vein.
