Irregular Heartbeat

1 Irregular Heartbeat Summary

Irregular or abnormal heartbeat, also known as arrhythmia is a condition in which the heart beats out of rhythm. The regular rhythm of the heart is normally adequate for the functioning, which is around 50-100 beats per minute in an adult. The rate is slightly higher in children when compared to adults.

Abnormal heart rhythms include: 

  • Tachycardia – this condition is characterized by the fast beating of heart. Tachycardia may occur in the upper chambers of the heart, known as supraventricular tachycardia. When tachycardia occurs in the lower chambers it is known as ventricular tachycardia. The illness may increase the heart rate, referred to as sinus tachycardia.
  • Atrial fibrillation – it is the most common form of irregular heart rhythm. It is characterized by increased heart rate starting from one of the atrial chambers.
  • Brady cardia – condition in which heart rate is lower than 60 beats per minute is referred to as bradycardia.
  • Ventricular fibrillation – this abnormal rhythm occurs in one of the ventricles and is a serious condition that requires immediate medical attention.
  • Premature contractions – in this condition the heart skips a beat, resulting in irregular heartbeat. The skipped beat may not be felt in the pulse. Premature contractions may also result in extra or early heartbeats.

Abnormal heartbeats are often associated with a number of symptoms like:

Abnormal heart rhythms may be caused by a number of factors. High blood pressure is one of the most common causes of irregularity in heart rhythm. Some other common causes include coronary heart disease, medications, electrolyte imbalances in blood, changes in muscles of the heart, injury caused by heart attack, certain other medical conditions.

Healing after a surgery in the heart is also implicated in the development of irregular heartbeat. Several factors increase the risk of developing irregular heart rhythm.

Major among them are: 

  • Family history of heart conditions
  • Diabetes
  • Stress
  • Smoking
  • Obesity or being overweight
  • Sedentary lifestyle
  • Unhealthy food habits
  • High blood pressure
  • Health issues

During the physical examination, the doctor listens to the heart rhythm using a stethoscope. Electrical impulses are analyzed using an electrocardiogram (ECG). ECG helps to detect the type of abnormality in the heart rhythms and the probable cause of the same.

Echocardiogram or Echo is used to visualize the functioning and structure of the heart. Holter monitor is a diagnostic device worn for 24 hours during daily activities. This is used to evaluate the changes in heart rhythm through the day. A stress test helps to understand the effect of exercise on the functioning of the heart.

Treatment of irregular heartbeat depends on the actual cause of the condition. Lifestyle changes and diet may be helpful in controlling the symptom. Quitting smoking is one of the important lifestyle modification suggested for relieving abnormalities in the rhythm.

Other treatment methods are suggested when there is no relief with lifestyle changes. Implantation of a pacemaker, surgical repair of abnormality, and other procedures to correct the rhythm are the different treatment options for arrhythmia. Most of the cases of the irregular heartbeat can be corrected by treatment.

2 Causes

An irregular heartbeat may be caused by multiple factors. Abnormal heart rhythm may be caused by lifestyle factors, emotional triggers, certain medications, hormonal changes, heart conditions, and other medical conditions.

Some of the possible causes are:

Congestive heart failure – this is a chronic condition characterized by the buildup of fluid around the heart. This leads to inefficient pumping of blood to different parts of the body. Irregular heartbeat is a major symptom that indicates that the condition has worsened.

Congestive cardiomyopathy – or dilated cardiomyopathy, is a condition characterized by weak pumping by one of the chambers of the heart. This can lead to irregular heartbeat, failure of heart, and other complications.

Mitral valve prolapse – mitral valves are the valves present between left atrium and left ventricle. In mitral valve prolapse, the valves do not close properly causing leakage of blood back into the atrium. The heartbeat may become irregular with the prolapse of mitral valves.

Certain medications – digitalis is an example of a medication that can lead to irregular heart rhythm. Digitalis toxicity is a medical emergency caused by the toxicity of the medicine digitalis, the medicine used for the treatment of heart conditions. Amphetamines are stimulants, dependence to which may result in irregular heartbeats.

Hypertensive heart disease – heart conditions caused by high blood pressure or hypertension is referred to as hypertensive heart disease. Thickening of heart muscles, coronary heart disease, and heart failure are all examples of hypertensive heart disease. The different heart conditions caused by hypertension result in an irregular heartbeat.

Cardiogenic shock – this is a serious condition in which the damage of heart affects the supply of blood to different parts of the body. Rapid but weak heartbeat is a characteristic symptom of this condition.

Aortic dissection – this is also a medical emergency and is characterized by the entry of blood into the space between the walls of the artery. This usually happens when the inner walls of the aorta tear, allowing entry of blood.

Electrolyte imbalance – abnormal heart rhythms and weakness are characteristic features of low potassium levels in the blood. It may also lead to severe weakness of muscles. High potassium levels in the blood, called hyperkalemia, may also lead to irregular heartbeat.

Hypertension – this is a condition that increases the risk of many other conditions including heart attack, stroke, and coronary heart disease. Most of these conditions are associated with abnormal heart rhythm as an important symptom.

Hyperthyroidism – excessive production of thyroid hormone by the glands leads to hyperthyroidism. Weight loss, weakness, and irregular heartbeat are common symptoms of this condition.

Anaphylaxis – this is yet another medical emergency caused by the severe allergic reaction. Rashes, low pulse, and irregular heartbeat are major symptoms of anaphylaxis.

Hypoglycemia – this is a potentially dangerous condition seen in people with diabetes. It is characterized by low levels of sugar in the blood. Rapid heartbeat, blurry vision, unexplained fatigue, and headache are caused by hypoglycemia.

Hypothyroidism – reduced production of hormones by thyroid glands results in the condition called hypothyroidism. As thyroid hormones play an important role in maintaining a normal heartbeat, reduced production leads to irregular rhythms.

Dehydration – loss of body fluid more than intake leads to dehydration. This may cause irregularity in heartbeats.

Caffeine overdose – caffeine overdose is a lesser known cause of irregular heartbeat.

Injury from a heart attack, and healing after a heart surgery may also lead to irregularities in heart rhythm.

3 Diagnosis and Treatment

Review of symptoms and medical history and physical examination are the first steps in the diagnosis of the cause of irregularity in heart rhythm. Heart monitoring tests help to analyze the structure and functioning of the heart. This includes:

ECG – or electrocardiogram that is used to detect the electrical activity of heart. This procedure records the timing and duration of each electrical pulse and pattern during the functioning of the heart.

Holter monitor – this device is worn for a day to monitor the functioning of the heart during normal activities of the day.

Event monitor – this is a portable ECG device that records the electrical activity. It is usually activated when there is a significant symptom associated with a heart problem.

Echocardiogram – this procedure is used to visualize the size, structure, and functioning of heart at a given time.

Loop recorder – this device is implanted under the skin and monitors and records irregularities in heart rhythm.

When an arrhythmia is not triggered by normal activities, other tests are used to trigger abnormalities in the rhythm. A stress test is used to trigger changes in a heartbeat by exercise. Tilt table test is recommended if fainting is one of the associated symptoms.

This measures the changes in rhythm with the change in positions. Electrophysiological testing and mapping help to map the electrical impulses in the heart. Location of arrhythmia is detected using electrodes that stimulate the heart.

Treatment is initiated if arrhythmia causes significant symptoms. Slow heartbeats are treated with a pacemaker, a device that helps to steady the rate of beating. Increased rate of heartbeat is treated with vagal maneuvers, medications, cardioversion, and catheter ablation.

Vagal maneuvers include specific maneuvers that affect the vagus nerve, that control heartbeat. Anti-arrhythmic medication helps to control the heart rate and restore normal rhythm.

Cardioversion is used to control atrial fibrillation, in which a shock is delivered to the heart to restore the normal rhythm of the heart. In catheter ablation, the electrodes present at the tip of catheter tips use heat, cold, or radiofrequency to ablate some area of heart tissue, thus blocking the electrical pathway in the heart. This blocks the electrical stimulation that causes arrhythmia.

In addition to pacemaker other implantable devices are used to treat irregular heartbeat. Implantable cardioverter-defibrillator (ICD) are suggested for people who have a high risk of developing irregular heartbeats.

ICD is implanted under the collarbone and continuously monitors the rhythm of the heart. In the presence of abnormal heart rhythm, it produces low-energy shocks to restore normal rhythm.

Irregular heartbeats may also be treated with surgical repair, depending on the cause of the condition. In one of the methods called maze procedure, a series of incisions are made to create scar tissue.

This tissue interferes with the electrical pathway that causes arrhythmia. Severe coronary artery disease is treated with coronary bypass surgery. Alternative medicines are also tried for controlling this symptom.

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