Rapid heart rate is the condition where your heart beats faster than normal. This condition is also called as tachycardia.
A normal heart rate is 60 to 100 beats per minute in a healthy adult. Tachycardia is considered a heart rate of greater than 100 beats per minute. The situations in which your heart beat increases are exercises, performing any kind of activity, experiencing fear, anxiety or stress. In tachycardia, the heart rate in the upper chambers or lower chambers of the heart, or both the chambers is increased. Normally, heart rate is controlled by electrical signals that are sent across the heart tissues. But in tachycardia there will be an abnormality in the heart to produce rapid electrical signals. In some cases of tachycardia there are no symptoms or complications but, it disrupts the normal function of the heart, and increases the risk of stroke, or even causes sudden cardiac arrest or death.
Tachycardia is caused when something disrupts the normal electrical impulses that control the rate of heart's pumping action. Many conditions contribute to problems with the heart's electrical system. The causes include:
The symptoms of rapid heart rate include:
The diagnosis of tachycardia includes a physical examination with several other tests such as:
Electrocardiogram (ECG): It is a primary tool for diagnosing rapid heart rate. For performing ECG, small sensors are attached to chest and arms of the patient, to record the electrical signals that travel through the heart. Different patterns among the signals are determined to identify abnormalities in the heart rate.
Electrophysiological Test: It is used to confirm the diagnosis or to pinpoint the location of problems in the heart's circuitry.
During this test, a thin, flexible catheter, tipped with electrodes is placed on the groin, arm or neck and guided through the blood vessels to various spots in the heart. The electrodes can precisely map the spread of electrical impulses during each beat and identify the abnormalities in the circuitry.
Tilt Table Test: This test helps to understand how tacycardia contributes to fainting spells. The patient will be asked to lie flat on a special table, and then the table is tilted as if the patient is standing up. The doctor observes how the heart and nervous system responds to the changes in position.
The treatment for tachycardia aims to slow down the heart rate, prevent future episodes and minimize the complications.
The heart rate can be decreased by Vagal maneuvers. It affects the vagus nerve that helps regulate the heartbeat. The maneuvers include coughing, bearing down, and putting an ice pack on the face. If vagal maneuvers do not stop the fast heartbeat, an anti-arrhythmic medication (intravenous) is required to restore a normal heart rate. Oral anti-arrhythmic drugs are also prescribed by the doctors. They include flecainide or propafenone. Some other medications that may be prescribed in combination with anti-arrhythmic medications are calcium channel blockers or beta blockers.
Cardioversion: In this procedure, a shock is delivered to the heart through paddles or patches on the chest. The current affects the electrical impulses in the heart and restores a normal rhythm. It is preferred when maneuvers and medications are ineffective.
Catheter Ablation: In this procedure, the doctor inserts catheter into the groin, arm or neck and guides them through the blood vessels to the heart. Electrodes at the catheter tips use heat, extreme cold or radiofrequency energy to ablate the extra electrical pathway, preventing it from sending electrical signals. This procedure is highly effective for supraventricular tachycardia. It can also be used to treat atrial fibrillation and atrial flutter.
Implantable Pacemaker: It is surgically implanted under the skin. When the pacemaker detects an abnormal heartbeat, it emits an electrical pulse to resume a normal heart beat.
Implantable Cardioverter-Defibrillator (ICD): It is surgically implanted into the chest. The ICD continuously monitors heartbeat and detects an increase in heart rate and delivers precisely calibrated electrical shocks thereby restoring a normal heart rhythm. It is recommended in life-threatening conditions of rapid heartbeat.
Surgery: In some cases, an open-heart surgery may be necessary to destroy an extra electrical pathway. In another type of surgery called the maze procedure, small incisions are made in heart tissue to create a maze (a pattern) of scar tissue. The scar tissue does not conduct electricity as it interferes with stray electrical impulses that lead to increased heart rate.