Diagnosis of Abnormal Heartbeat
To diagnose an abnormal heartbeat, doctor will review your symptoms, medical history and conduct a physical examination.Several test can help to diagnose an abnormal heartbeat. These may include:
1. Medical History
To diagnose an arrhythmia, doctor asks about eating and physical activity habits, family history, signs and symptoms and other risk factors for abnormal heartbeat.
2. Physical Examination
During physical examination few points are checked by the doctor:
• Checking for swelling in your legs or feet, which could be a sign of an enlarged heart or heart failure.
• Checking of your pulse to find out how fast your heart is beating.
• Listen to the rate and rhythm of your heartbeat.
• Listen to your heart for a heart murmur.
• Look for signs of other diseases, such as thyroid disease, that could be causing the abnormal heartbeat.
3. Diagnostics Tests
Blood Tests: to check the level of certain substances in the blood, such as potassium and thyroid hormone, that can increase your risk of abnormal heartbeat.
CT Coronary Angiography: to know the blockages.
Echocardiography(echo): This tell about the size and shape of your heart and how well it is working.
Chest X-Ray: to know your heart is larger than normal
Electrocardiogram (ECG): This tells how fast the heart is beating.
Holter monitor : This portable ECG device can be worn for a day or more to record your heart's activity as you go about your routine.
Implantable loop recorder: to detect abnormal heart rhythms.
Ultrasound: to diagnose a suspected fetal arrhythmia in the womb.
Stress test: Some arrhythmias are triggered or worsened by exercise. During a stress test, you'll be asked to exercise on a treadmill or stationary bicycle while your heart activity is monitored. If doctors are evaluating you to determine if coronary artery disease may be causing the arrhythmia, and you have difficulty exercising, then your doctor may use a drug to stimulate your heart in a way that's similar to exercise.
Tilt table test: Doctor may recommend this test if you've had fainting spells. Your heart rate, EKG reading, and blood pressure are monitored as you lie flat on a table. You lie on a table that moves from a lying-down position to an upright position. The change in position may cause you to faint.
Treatment of Abnormal Heartbeat
There are few points that one should follow if he/she has a problem of abnormal heartbeat:
1. Healthy Lifestyle Changes
To prevent heart arrhythmia, it's important to live a heart-healthy lifestyle to reduce your risk of heart disease. A heart-healthy lifestyle may include:
• Eat a heart-healthy diet
• Stay physically active and keep a healthy weight
• Reduce blood pressure
• Control cholesterol level
• Avoid tobacco smoke
• Avoid caffeine and alcohol
• Reduce stress, as intense stress and anger can cause heart rhythm problems
• Use medications with caution, as some cold and cough medications contain stimulants that may trigger a rapid heartbeat
2. Medicines
Some medicines are used in combination with each other or together with a procedure or a pacemaker. If the dose is too high, medicines to treat arrhythmia can cause an irregular rhythm.
• Adenosine to slow a racing heart. Adenosine acts quickly to slow electrical signals. It can cause some chest pain, flushing, and shortness of breath, but any discomfort typically passes soon.
• Atropine to treat a slow heart rate. This medicine may cause difficulty swallowing.
• Amiodarone is used to treat irregular heartbeat or Ventricular Ectopics. It is used to maintain a regular, steady heartbeat.
• Beta blockers to treat high blood pressure or a fast heart rate or to prevent repeat episodes of arrhythmia. Beta blockers can cause digestive trouble, sleep problems, and sexual dysfunction and can make some conduction disorders worse.
• Blood thinners to reduce the risk of blood clots forming. This helps prevent stroke. With blood-thinning medicines, there is a risk of bleeding.
• Calcium Channel Blockers to slow a rapid heart rate or the speed at which signals travel. Typically, they are used to control arrhythmias of the upper chambers. In some cases, calcium channel blockers can trigger ventricular fibrillation. They can also cause digestive trouble, swollen feet, or low blood pressure.
• Digitalis, or digoxin to treat a fast heart rate. This medicine can cause nausea and may trigger arrhythmias.
• Potassium Channel Blockers to slow the heart rate. They work by lengthening the time it takes for heart cells to recover after firing, so that they do not fire and squeeze as often. Potassium channel blockers can cause low blood pressure or another arrhythmia.
• Sodium Channel Blockers to block transmission of electrical signals, lengthen cell recovery periods, and make cells less excitable. However, these drugs can increase risks of sudden cardiac arrest in people who have heart disease.
3. Procedures
• Electric shock or Cardioversion: It is a medical procedure by which an abnormally fast heart rate (tachycardia) or other cardiac arrhythmia is converted to normal rhythm using electricity or drugs.
• Cardiac ablation: It is a procedure that can correct heart rhythm problems (arrhythmias). Cardiac ablation works by scarring or destroying tissue in your heart that triggers or sustains an abnormal heart rhythm. In some cases, cardiac ablation prevents abnormal electrical signals from entering your heart and, thus, stops the arrhythmia.
• Implantable Cardioverter Defibrillators (ICDs): Defibrillators are devices that restore a normal heartbeat by sending an electric pulse or shock to the heart. They are used to prevent or correct an arrhythmia, a heartbeat that is uneven or that is too slow or too fast. Defibrillators can also restore the heart’s beating if the heart suddenly stops. Different types of defibrillators work in different ways.
• Pacemaker: Electrical impulse from our heart muscle, the myocardium causes heart to beat (contract). This electrical signal begins in the Sino Atrial (SA) (specialized are of muscle which has inherent property to generate electrical impulse) node known as natural pacemaker, located at the top of the right atrium (chamber-1). SA node is called pacemaker as it produces impulse & sets the pace for contraction of heart. When this natural pacemaker of the body goes wrong, artificial pacemaker are implanted in many people and they take over the work of this natural pacemaker i.e. SA node in producing impulses.
Identification of Arrhythmia
Palpitation, Breathlessness, Chest Pain, Dizziness, Fainting (Syncope), Tiredness, Uneasiness, Light Headedness.
Risk factors
Certain conditions may increase your risk of developing an arrhythmia. These include:
1. Coronary artery disease, other heart problems and previous heart surgery
2. High Blood Pressure | Congenital Heart Disease
3. Thyroid Problems | Diabetes | Obstructive Sleep Apnea | Electrolytic Imbalance
Complications
Certain arrhythmias may increase your risk of developing conditions such as:
1. Stroke or Paralysis
2. Heart Failure
3. Sudden Cardiac Arrest
4. Worsening Arrhythmia
Few important terms
LBBB or RBBB (Bundle Branch Block)
Lots of people come to know from their ECG that they have some defect in the Pace Maker System of the heart but they are told that since they do not have any symptoms they do not any treatment. One of them is Bundle Branch Block – it may be the right or Left Bundle Branch. This kind of heart disease is called RBBB or LBBB.
The defect in these cases is delay or default in the Bundle of His – the nerve that transmits electrical signals to the Left or Right lower chambers of the heart or ventricles (which ultimately lead to their pumping action). This block is in the electric signals – which now reach directly through the muscles and the ventricles beat almost normally. So, the work of the heart goes on as usual. The patient does not need any treatment or have any symptoms.
The cause of the interruption is mostly a shortage of blood due to the death of the area of the heart muscles through which the nerve thread passes. This occurs because of fat deposits in the branch of the coronary arteries supplying that area. This is like a very minor heart attack – which goes unnoticed. Such patients, if they do not take care of their diet, lifestyle, and blood lipid levels, further progress to the next stage – Bi Fascicular Block (both RBBB and LBBB together) and then Complete Heart Block. The Complete Heart Block ( it is an electrical signal block) needs External Pace Maker Implantation.
Though the most common cause of Bundle Branch Blocks is coronary artery blocks/heart attacks – the other uncommon causes of LBBB or RBBB are genetic defects in the heart (from birth), Cardiomyopathy, Myocarditis, High Blood Pressure or Pulmonary hypertension.
Ventricular Ectopics (Missing beats)
Almost all the heartbeats that we have, generate from the S A Node or original pace Maker of the heart which is located in the wall of the Right Atrium. They first stimulate the Atria (the two upper chambers) and then the Ventricles (the lower Chambers). This leads to a normal heartbeat. But sometimes the ventricles contract on their own without any signal from above. This leads to an extra beat in the heart called Ectopic Beat or VPC (Ventricular Premature Beat). It can be felt by the patient if we count the pulse as a missing beat. Many healthy people can get it and till 3000 VPCs per day (3%) it may be considered normal. They may be because of stress, extra caffeine, extra alcohol, and strenuous exercises.
But if they become too frequent or come in doubles or triples – it can lead to giddiness or fainting. This needs treatment. There are medicines (like Amiodarone) that can control them – but the underlying cause is again Coronary Heart Disease or Shortage of blood to some part of the heart due to Coronary artery fatty deposits.
If the reasons (called Risk factors) of the fat deposits (like Cholesterol, Triglycerides, High BP, High Sugar, Smoking, stress, lack of exercise, obesity) is not withdrawn they may worse and lead to Ventricular Tachycardia or Ventricular Fibrillation. This condition now becomes very serious as the ventricles continuously generate Ectopics – which may even lead to death. Such patients immediately need Electric Shock (Cardioversion) to restore normal beats. If the preventive care is still not taken - Later on they may need to be repeated electric shocks using ICD device.
P -SVT or SVT (Paroxsysmal Supra Ventricular Tachycardia)
This is a kind of rapid or very fast heartbeat (130-200) and occurs for a short duration. Patients feel uneasy and can feel the high speed of the heart. This is caused by the existence of some of the electrical signal generators in the atrial wall near the main pacemaker or S A Node. They sometimes become active and generate fast signals which take over the SA Node function. This is mostly called AVNRT (Atrio-Ventricular Nodal Re-entrant Tachycardia).
Since it is a temporary fast beat – it is never life-threatening. It is usually stimulated by Stress, Anxiety, caffeine, drugs, or Alcohol. It does not usually need treatment, but it occurs very frequently can be treated with drugs like Calaptin. Vagus nerve stimulation by massaging in the back of the lower part of the ear can revert it on many occasions.
The Hospital system usually wants to do RFA (Radio Frequency Ablation) in such cases which is not only invasive but often fails as they try to burn the suspected nerve areas on the wall of the Atria by trial and error method. This should be tried only if the lifestyle and medicines fail.
EPS or EP Studies (Electro Physiological Studies)
This is an invasive testing procedure to study the origin of certain types of Arrhythmia or irregular heartbeats. This usually needs inserting a catheter in your body – which is pushed to the selected chamber of the heart. Electrodes are also pushed along the catheter to study the electrical activity of the areas of the heart to search for the origin of the abnormal nerve location. It is a complex study and very few experts can give exact opinions on the test. However, it can be done if all methods of control of the irregular beats fail. It costs usually Rs. 30000-50000.