Monday, July 4, 2011

When it's out of rhythm

When it's out of rhythm


Does your heart seem to go too fast or skip an occasional beat? Learn what the problem could be.

What is an arrhythmia?

An arrhythmia is a change in the regular beat of the heart. The heart may seem to skip a beat or beat irregularly. It may beat very fast or very slowly. So it's basically all about the heart beat.

Are arrhythmias serious?

In some patients with serious symptoms, arrhythmias themselves are dangerous. It requires medical treatment to keep the heartbeat regular.

Some patients have a very slow heartbeat (bradycardia), causing them to feel lightheaded or lose consciousness. If left untreated, the heart may stop beating and cause death.

In others, who have a very fast heart beat, this may cause loss of consciousness due to drop in blood pressure. If untreated within six minutes it can cause sudden cardiac arrest.

What are the symptoms of an arrhythmia?

Patients may feel their heart beat very fast and experience a fluttering in their chest or notice a skipped heart beat. Other symptoms are dizziness, fainting spell, difficulty in breathing or chest discomfort. Check with your doctor or see a cardiologist/electrophysiologist'.

What happens during normal rhythm?

The heart is a muscular pump divided into four chambers two atria (upper chamber) located on the top and two ventricles (lower chamber) located on the bottom. Normally each heartbeat starts in the right atrium. A specialised group of cells called the sinus node or natural pacemaker sends an electrical signal. The signal spreads throughout the atria to the area between the atria and ventricle called the atrioventricular (AV) node, which connects to a group of special pathways that conduct the signal to the ventricles below. As the signal travels through the heart, the heart contracts. First the atria contract, pumping blood into the ventricles and a fraction of a second later, the ventricles contract, sending blood throughout the body. Normally the whole heart contracts between 60 and 100 times per minute. Each contraction equals one heartbeat.

Are there different types of arrhythmias?

Arrhythmias are identified by where they occur in the heart (atria or ventricles). Also by what happens to the heart's rhythm. Those arising in the atria are called atrial or supraventricular (above the ventricles) arrhythmias. In general, ventricular arrhythmias caused by heart disease are the most serious.

How is it diagnosed?

A good medical history and a thorough physical exam is a must. The tests done are Resting ECG; Exercise ECG (stress test); 24-hour Holter monitoring; Transtelephonic monitoring; 2D Echocardiography; Electrophysiologic Study; Head-Up Tilt Test

How is it different from heart attack?

Arrhythmias are caused by a heart rhythm problem. A heart attack is caused by a circulation problem. A heart attack refers to the death of heart muscle tissue from the loss of blood supply.

Think of a heart attack as a "plumbing problem"; arrhythmia is an electrical short circuiting. A heart attack is often preceded by symptoms such as pain in the chest, arm, upper abdomen, or jaw. Nausea and sweating are common. Heart attack patients usually remain conscious.

Is the implantable cardioverter-defibrillator (ICD) useful in cases of arrhythmia?

ICD is a real lifesaver as it prevents sudden cardiac death. These devices save patient who have malignant arrhythmias coming from the lower chamber of the heart as they have higher incidence of dying suddenly. No medicines can prevent these arrhythmias to recur 100 per cent nor it is practically possible to give DC shocks to these patients when the need arises once they are sent home. Hence It is implanted below the skin, under the collar bone and patient is guarded from the nightmare of sudden death. It is like an Emergency Department implanted in patient's chest. The patient can lead a normal life; in fact he/she has a better quality of life after device implantation.

What is the future of Electrophysiology (EP) in India?

Very bright. It's becoming an established branch. More cardiologists are interested in it. New devices and mapping techniques are being introduced. More challenging ventricular and atrial arrhythmias can be treated.

Is there any way to prevent cardiovascular disease?

Prevention of cardiovascular diseases is comparatively easier and cheaper. People should improve their lifestyle, learn to reduce stress, quit smoking, change their eating habits, exercise regularly and also learn to relax. Spend at least 40-50 minutes on yourself (relaxing, exercising, enjoying). That is the least to keep healthy. It's not asking for too much.

The writer is a Delhi-based Consultant Cardiac Electrophysiologist.