Misunderstood Waves In The Heart

Implantable cardioverter-defibrillator(ICD) is an implantable medical electronic substance, which is used on therapeutic and diagnostic propose. The ICD consists of a pulse generator and wires, and the wires will pass via a vein to the right chambers of heart. The pulse generator is usually implanted in the left ventricular region.

The heart is an organ that pumps blood around the body by using 2 separate pumps side by side. The left side of the pump deals with oxygenated blood from the lungs whereas the right one deals with deoxygenated blood from the body. Each pump has 2 chambers called atrium and ventricle. The walls of the atrium are thinner than the ventricle because the atrium only has to pump blood to a short distance (to the ventricle) whereas the ventricles need to pump blood to the rest of the body. The heart has 3 types of pacemaker cells called; Sino atrial (SA) node, Atrioventricular (AV) node and bundle of His which make up the electrical conduction system. SA node found in the right atrium sends a wave of depolarisation to the neighbouring muscle junction, to the left atrium by the Bachmann’s bundle and also to the AV node by the internodal tract. AV node delays the wave of depolarisation causing the ventricle to contract after the atria. The AV node causes that delay to allow all the blood to fully move from the atria to the ventricle then the ventricle can contract sending the blood out the heart. After the AV node has delayed the wave of depolarisation, the wave continues down by a bundle of His and the fibres split up by the Purkinje fibres allowing the muscle to get involved. The wave of electrical released from the fibres causes the ventricles to contract.

The design of these hearts is close to the structure of the natural heart. The heart that humans carry has two pumps and four chambers. The right atrium gathers oxygen-drained blood and pumps it to the lungs. The left atrium receives oxygen-rich blood from the lungs to and pumps this blood out of the body. The valves’ function is to control the blood flow (Raghunandan Avula). On the other hand, artificial heart has three subsystems placed under the skin. These subsystems are the heart pump, a pump controller, and a power source. The battery of the heart is charged with a special magnetic charger. Energy from the external charger is transferred to internal battery through an energy transfer device known as transcutaneous energy transmission (National Heart, Lung, and Blood

The concept of non-invasive cardiac pacing has been present for about 200 years. In 1791 Galvani reported that an electrical current applied across the heart of a dead frog resulted in myocardial contraction [1]. However, non-invasive pacing was not made practical until Dr. Paul Zoll's work in the early 1950s. In 1952 Zoll reported the successful delivery of current from a generator through subcutaneous needle electrodes, which resulted in fixed rate pacing of two patients with ventricular standstill.3 He later reported the development and successful use of the first true noninvasive pacemaker and monitor. This device used a pair of 3-centimeter diameter metal electrodes secured to the chest wall with a leather belt and delivered 2-20 millisecond,

Echocardiography (echo) is a common procedure used by medical practioners to observe a patient’s heart. Also known by the term heart ultrasound, it is a medical procedure that takes a dynamic image of the heart with sound waves. This test makes use of certain physical principles to create pictures of your heart's movement, while providing unique information as compared to what a standard ECG might produce; however, like most other medical procedures, there are risks associated with some forms of this test.

Cardiac muscle is found in the heart, hence why is it named this. The heart is able to perform a beat because cells are connected together by intercalated discs. The heart is an involuntary muscle, meaning it works automatically. The rate of the contractions are quite steady but the hearts pacemaker can be made to go quicker or slower by certain nerves. The presence of a pacemaker enables the cardiac muscle to control its own contraction rhythm. If the nervous system doesn’t produce a stimulation then the pacemaker will remain a regular heart rhythm. Cardiac muscle is like a rectangular shaped cell which contains regions known as intercalated discs. Within these discs there are gap junctions and desmosomes. The gap junctions are responsible

Secondly, you're going to learn about how the heart works. “The heartbeat is triggered by an electrical pulse that travels down a special pathway through your heart. The impulse starts in a small bundle of cells located in the right atrium, called the SA node. The electrical activity spreads through the walls of the

Artificial Cardiac Pacing (ACP) is an effective treatment for patients suffering from bradycardia. Atrio-ventricular block (AVB) is a common cause of bradycardia indicating the need for the implantation of a permanent pacemaker (PM). Roughly 3000 pacemaker devices are being implanted in Israel annually, more than half of them due to AVB block. A possible complication of this treatment for patients with AVB is the development of heart failure secondary to prolonged pacing via the right ventricle with a normal baseline heart function (Right Ventricular Pacing Induced Cardiomyopathy; RV-PICM).

In the US, heart attacks kill more people than any other single cause. Many of the deaths are caused by electrical disturbances in a damaged heart that cause it to fibrillate (Pool). Despite current overwhelming interest in the operations of the human heart, for most of history the human heart has been regarded as a "forbidden organ too delicate to tamper with" (NOVA). In fact, it might have remained so, were it not for World War II where military doctors, faced with massive numbers of injuries ushered the world into our current medical trajectory.

An electrocardiogram, or ECG, is a visual representation of the electrical impulses of the heart. An ECG is performed with an electrocardiograph, which uses electrodes to record the electrical impulses of the heart. The ECG represents the heart’s electrical impulses as positive or negative deflections which creates the ECG waveforms. These waveforms are a represented on an ECG as the P-QRS-T sequence.

The function of the heart is to power the entire circulatory, transport nutrients, oxygen, waste, heat, hormone, immune cells throughout the body, over and over again. Arrhythmias are abnormal heart rhythms arrhythmias that are caused by problems with the electrical system that regulates the steady heartbeat. The heart rate may be too slow or too fast; it may stay steady or become chaotic (irregular and disorganized). Some arrhythmias are very dangerous and cause sudden cardiac death, while others may be bothersome but not life threatening. This paper will discuss, the cardiac conduction system, arrhythmia types, symptoms, diagnosis, and treatments.

Synchronized electrical cardioversion uses a therapeutic dose of electric current to the heart at a specific moment in the cardiac cycle. This is used when patients have a tachycardia, when it is so severe and critical, the physicians in the medical intensive care unit perform these procedures. The procedure is performed by using two electrode pads. Each pad has metallic plate which has saline gel on it, the pads are usually placed on the patient's chest, although one could be on the patient’s back, the other on their chest. The pads and cables are connected to the electrocardiography display screen. The cardioverter, is used to deliver a reversion shock, and depending the patient's’ needs, the amount of electric current and time in between shocks will differ. The R wave on the electrocardiography is an indicator of when to deliver the shocks to the patient because timing the shock to the R wave is crucial, because it prevents the shock during the vulnerable period (Intensive care medicine.

There are three main types of blood vessels, the arteries, capillaries and veins. Blood vessels are responsible for the blood to flow dynamically from the heart to every part of the body and then back to a continuous cycle which takes about one minute (Tim Taylor, 2014). The size of the blood vessels correlates with the amount of blood that passes through the vessel (Tim Taylor, 2014). The hollow area of the blood vessel is called the lumen which can either be thin or thick depending on which organ it flows through (Tim Taylor, 2014). A thin layer of squamous epithelium, known as endothelium, is a thin lining in the blood vessels that allow blood cells to stay inside of the

An artificial pacemaker is an electronic surgically-implanted device to regulate slow or erratic heartbeats. They are indicated for the patients with symptomatic bradycardia. A pacemaker is a small electronic pulse generator sealed in a titanium case with one (monopolar) or more usually now, two (bipolar) electrode leads

The pacemaker is a complex device that sends electrical impulses to the heart to keep it in a normal rhythm. Most of the time doctors implant pacemakers to treat arrhythmias. “Arrhythmias are problems with the rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm” (MedicineNet). Arrhythmia has two different stages and they're called: bradycardia and tachycardia. Tachycardia is the condition where the heart beats too fast and bradycardia is the condition where the heart beats too slow. The pacemaker then changes the defective rhythm