Holter monitor

A holter monitor or ambulatory electrocardiography device is a portable equipment that is used to monitor electrical activity of the heart. There are a series of electrodes attached to the chest of the patient that can record electrical signals from the heart. There is a recording monitor that can be carried in the pocket or worn around the neck. The patient's EKG for 24 hours is recorded. Values such as average heart rate, maximum and minimum heart rate are calculated. ECG tracing using Holter monitor is conducted on patients who suffer prolonged fatigue and episodes of low blood pressure and fainting.

A Holter monitor aids in recording any abnormal activity of the heart. The Holter monitor is worn by the patient as he/she goes about his daily routine. It is possible to observe occasional cardiac arrhythmia, atrial fibrillation and atrial tachycardia with a Holter monitor. This device is also advised for patients who have suffered a heart attack or under cardiac medication. A Holter monitor aids in monitoring the performance of a heart pacemaker. Smoking and close proximity to devices such as magnets and metal detectors and some electrical appliances can affect the Holter monitor readings.

Tachycardia

Measuring the heart rate is one of the key diagnostic methods in identifying a cardiac condition. The normal heart rate of an individual is 60 – 100 when the cardiac muscle is in resting condition. Tachycardia is a condition in which the normal heart rate of a person increases and the entire rhythmic contraction of the heart muscle is affected. Sinus Tachycardia is usually a response of the cardiac muscle to exercise, stress or underlying illness. Although there are many forms of tachycardia, it is broadly classified into two predominant types depending upon the chambers of the heart.

Atrial Tachycardia

The conditions are associated with the atrial chambers or the upper chambers of the heart. They are further classified.

Atrial Fibrillation: In this condition, the cardiac electrical conductivity is rapid and irregular leading to irregular heart muscle contraction. The rapid contractions thus produced affect the ventricles. This type of cardiac disease is associated with hypertension and hyperthyroidism. Another associated condition related to atrial fibrillation is atrial flutter.

Supra Ventricular Tachycardia: This condition is caused above the ventricles causing abnormal cardiac conduction leading to superimposed or overlapped signals. It is related to AV node abnormalities in which the cardiac signal arriving at the AV node is split into two with the rebound of one signal to the atria and one signal to the ventricle. These conditions can also lead to Wolf Parkinson's disease which emphasizes the deflected pathway of the arriving signal.

Ventricular Tachycardia

Ventricular tachycardia is a serious cardiac condition. Ventricular fibrillation and associated tachycardia is because of rapid and uncontrolled emergence of cardiac electrical signals leading to extreme arrhythmia and subsequent heart failure.

Risk factors

Cardiac diseases are predominantly caused because of stress or congenital deformities. In most cases obesity, alcohol, smoking and drug abuse have been the predominant sources of increased mortality because of cardiac attacks.

Diagnosis and Treatment

Cardiac conditions are detected with an ECG. The ECG reveals the cardiac conductivity in the four chambers of the heart. Altered patterns can be observed clearly in comparison with the normal graph generated by one cycle of cardiac conduction. Holter monitor, an advanced and portable device performing similar function is used on patients to monitor their cardiac activity for a period of 24 hours. Treatment methods usually include administration of beta-blockers to control arrhythmia and to prevent the occurrence of stroke. Vagus nerve maneuvers and defibrillation methods often help in the recovery of the heart muscle from rapid arrhythmia.