SVT’s are rapid rhythm originated from the atrium or atrioventricular node in the absence of bundle branch of block. It gives normal QRS conduction and this kind of arrhythmia is also called narrow complex tachycardia. There is multi-mechanism to this kind of arrhythmia as what we called the reentrant arrhythmia or automaticity, this is what we called spontaneous repetitive firing from a single focus and the third mechanism is what we called the triggered arrhythmia, which is dependent with membrane potential that follows the action potential or we can call that, after- depolarization can cause this kind of SVTs.

A step in diagnosing this kind of disease first is to do Electrocardiogram or ECG. This procedure allows us to determine which kind of supraventricular tachycardia or SVT’s is present. This procedure can determine if the rhythm is Regular, where most likely an atrial fibrillation or atrial flutter with variable conduction or multifocal atrial tachycardia; or Irregular Atrial flutter where the T waves are seen in a rate of 240 – 320 bpm and the presence of P waves that preside the QRS complexes with conduction of 2- 1 : 3-1.

Moreover, there are also several kinds of Regular-type SVT’s. These include sinus tachycardia, sinus node reentry, atrial flutter, atrial tachycardia also called as “AV nodal reentry tachycardia” or “junction tachycardia”. Sinus Tachycardia and Junction Tachycardia usually have very gradual onset, whereas the other type of SVTs, their onsets are more suddenly. In SVTs, the rate can also be helpful in differentiating the types since Sinus Tachycardia cannot typically go over 240 bpm. With morphology, it can help determine the kind of Arrhythmias. Also, if retrograde P waves are negative in the inferior leads, it is in favor for AVNRT or Junctional Tachycardia. Sinus Tachycardia has an onset and termination that were gradual, and the heart rate is between 100-200 bpm, the P waves are identical to Normal Sinus Rhythm but are relationship block.

Aortic Stenosis is the narrowing of the aortic valve orifice caused by failure of the leaflets to open normally. Its pathogenesis is most commonly progressive calcification and degeneration of a trileaflet or congenitally bicuspid valve. It is now recognized that calcific aortic stenosis is in fact an active disease process that shares similarities to atherosclerosis and involves inflammation, lipid accumulation, and calcification of the leaflets.

On the other hand, rheumatic valve disease is a rare cause of aortic stenosis in industrialized nations. However, in developing countries, there remains a significant prevalence of rheumatic valve disease. The aortic valve disease is almost never present in isolation, and there is invariably concomitant mitral valve disease. Other rare cause of aortic stenosis include connective tissues diseases such as systemic lupus erythematous and ochronosis.

We all are familiar with the term “Heart attack”. But, how many of us are aware of the factors that act to cause it? There are a number of risk factors to be taken in account for the heart attack. Generally, the causes can be divided into two factors:

predisposing factors and/or precipitating factors. Predisposing factors refer to those that are inevitable i.e. which are inherited by an individual genetically or biologically. In simpler words, these are the possible causes/triggers that an individual does not have the power to change. On the other hand, precipitating factors refer to those that still poses risks to an individual but can be changed or modified. These include lifestyles and diet.

One of the factors that poses risks for heart attacks is Heredity. It can neither be changed nor modified. Studies have shown an increased risk of heart attacks to the individuals whose siblings, parents and/or grandparents had experienced early heart attacks (by the age of 55 for males and by the age of 65 for females). Those children whose parents are affected with heart diseases are also more likely to develop it themselves. African Americans are at higher risk of heart diseases as they are known to have more severe high blood pressure than the Caucasians. Mexican Americans, American Indians, native Hawaiians and some Asian Americans are also at high risk of being affected with heart diseases which is partly due to higher rates of obesity and diabetes. People with a strong family history of heart disease are likely to have one or more risk factors. Just as you can't control your age, sex and race, you do not have the power to control your family’s history. We do not have the ability to choose what to inherit from our parents. Therefore, it's even more important to treat and control those risk factors you have the power to change.

One of the unhealthy habits that invites hundreds of diseases is smoking. Smoking has become a common practice among the people since ages. Even though this factor is considered modifiable, one finds it extremely hard to overcome once it has become a habit. Not only smoking, but long-term exposure to secondhand smoke (passive smoking) also has been known to make an individual vulnerable to the risk of a heart attack. Formaldehyde is a chemical for embalming and preserving tissues. But, inhalation of formaldehyde can result in irritation and damage to the lining of the nose and throat. Formaldehyde and other such harmful chemicals make up the ingredients of a cigarette.

Aside from that, the effects of long-term smoking include damages in the lining of arteries too. This ultimately results in building up of fatty material (atheroma) around the inner walls that causes narrowing of arteries. Heart attacks are likely to occur even at young age if this habit is not overcome through utmost self-control and a strong drive from within.

Hyperlipidemia literally means high cholesterol. It is a harmful health condition which is highly genetic and/or hereditary. Cholesterol is a waxy, fat-like substance that is found in all the cells in our body. Our body needs some of the cholesterol to make hormones, vitamin D, and substances that help us digest our food. Our body makes all the cholesterol it needs. Cholesterol is also found in some of the foods we eat. If we have too much cholesterol in our blood, it can combine with other substances in the blood to form plaque. Plaque sticks to the walls of the arteries, ultimately narrowing it and/or totally occluding minute blood vessels. . This results in decreasing and/or retaining of blood flow in the heart and/or some vital organs ultimately causing deficiency in the amount of oxygen reaching the tissues eventually killing most or all of the cells if left untreated. Plaques can travel through the arteries of the heart which causes heart attack and stroke.

Diabetes is a metabolic disorder. It not only causes problems in a single organ but to the circulatory system which is concerned with the transport of oxygen and carbon dioxide as well. Diabetes is a very serious risk factor for the heart-related diseases. In fact, it is as much serious as smoking, high blood pressure and high blood cholesterol. People suffering from type 2 diabetes have the same risk of heart attack and dying from heart disease as the people who already have had heart attacks. It is so because over time, high blood glucose from diabetes can damage the blood vessels and the nerves which control the functions of the heart and blood vessels. To conclude, the longer an individual has had diabetes, the higher the chances will be that he/she will develop heart disease/s.

Hypertension, commonly known as “high blood pressure” is a “silent killer”. It is a common cause for several problems including heart attacks. Every ounce of blood flows to every corner of the body. Therefore, high blood pressure can cause lots of systemic problems, particularly affecting the major organs of the human body including the heart. Over time, arterial walls suffer injury as there is too much constant pressure against it. This creates tears in those arterial walls. These tears may break/rupture over time causing hemorrhage and/or clot deposition. Both of which are a great threat to us as they cause serious problems such as hemorrhage to shock and clots to thrombosis and/or embolism. Either one of these eventually triggers heart attacks or strokes.

Sedentary lifestyle is hazardous to one’s health. Although it’s not enough to cause heart attacks alone, it is considered one of the risk factors that aggravates the risks. The main problem of having a sedentary lifestyle is that the individual’s blood flow will become sluggish. This causes the organs to become insufficiently perfused, and that’s where problems arise. Continued inactivity means that the excess calories are not worked up. And thus they are deposited as fats which are retained by the human body. Over time, as the individual slowly but steadily gains weight, this leads to another problem: overweight. The more the weight is gained, the more is the workload to the heart. This increased workload urges the heart to pump harder and thereby demands more oxygen. Ultimately, this induces swelling, inflammation and thickening of the heart. And thus, heart attacks are more likely to occur at any time.