First Degree Heart Block: Causes, Symptoms, Treatment, Image

According to a study by Dorairaj Prabhakaran et al. in 2016, cardiovascular diseases (CVD) are the leading cause of mortality in India. Among these, first-degree heart block has a prevalence of 1-1.5% until the age of 60. After 60, the prevalence rises to about 6%.

Imagine your heart as a well-coordinated orchestra where each beat is perfectly timed. In first-degree AV block or heart block, there’s a slight delay in transmitting electrical signals between cardiac chambers. But is it serious, and what problems does it cause? The following blog discusses its causes, symptoms, and treatment. Read on to find out. 

In a healthy heart, the electrical signals from the atria (the upper chamber of the heart) to the ventricles (the lower cardiac chamber) move efficiently. These impulses move through the AV node (a group of cardiac muscle cells between the chambers). 

In first-degree heart block, also called first-degree atrioventricular (AV) block, the electrical activity is slower than average. However, all signals still reach the ventricles. 

Is First-Degree Heart Block Serious?

There are three types of heart blocks - first, second, and third-degree. 1st degree heart block is generally considered the mildest form of the issue. In many cases, it is not considered a severe condition. The delay in the conduction of electrical impulses is minimal, and individuals often do not experience evident symptoms. However, sometimes, it can progress to second or third-degree AV blocks.

Many individuals with 1st degree AV block may not experience any related health issues. It is commonly discovered incidentally during routine electrocardiograms (ECG) performed for other reasons.

In some cases, individuals may experience first-degree heart block symptoms like the following: 

1. Lightheadedness

2. Dizziness

3. Palpitations or skipped heartbeat

4. Fatigue 

However, these symptoms are nonspecific. They can also be caused by factors unrelated to heart block.

First-degree heart block is typically caused by abnormalities in the cardiovascular electrical conduction system. The most common causes include:

1. Genetic Factors: Sometimes, people are born with cardiac issues due to genetic mutations or inheritance. This is known as a congenital heart block. 

2. Cardiovascular Diseases: A heart attack is the most common cause of AV block. Other issues like cardiomyopathy (cardiac muscle disease) and heart valve disorders can disrupt the normal conduction of electrical signals. 

3. Open Heart Surgery: During the operation, manipulating the cardiac tissues and conduction pathways can disrupt the standard electrical signals, leading to first-degree heart block. 

Several factors can increase the risk of first-degree heart block. However, having multiple aspects does not necessarily indicate that individuals will develop this condition. These risk factors include: 

1. Age: The risk tends to increase with age as degenerative changes in the electrical system of the heart may occur over time. The AV node may also develop fibrosis (thickening and scarring of the tissue). 

2. Gender: A 1-degree AV block is generally more common in males due to the increased release of stress hormones.

3. Athletic Training: Sportspeople who undergo intense training have an increased disease risk. 

4. Medications: Medications like beta-blockers and calcium channel blockers may affect the electrical conduction system and contribute to heart block. 

5. Inflammatory Conditions: The following conditions can lead to inflammation affecting the cardiovascular conduction pathways:

1. Lyme disease (infection caused by borrelia bacteria)

2. Chagas disease (an infectious disease from the parasite Trypanosoma cruzi)

3. Diphtheria (severe bacterial infection from Corynebacterium diphtheriae)

6. Autoimmune Disorders: Some diseases may increase the risk due to fibrosis in the heart tissue. These conditions include: 

1. Rheumatoid arthritis (a chronic inflammatory disorder impacting the joints)

2. Scleroderma (immunological disease causing thickening and hardening of the skin and other body parts)

People with congenital heart block are at a significantly increased risk of acquiring the condition. However there are methods to prevent its progression. Tips for prevention of first-degree heart block include: 

1. Regular Exercise: Engaging in consistent physical activity can help maintain a healthy heart and avoid AV block. People should get at least 150 minutes of moderate aerobic workout a week.

2. Heart-Healthy Nutrition: Individuals should eat a balanced diet rich in fruits, vegetables, lean proteins, and whole grains. Avoiding trans and saturated fats, cholesterol, salt, and added sugars.

3. Quitting Tobacco Use: Smoking is a significant risk factor for heart disease. Giving up its consumption can improve cardiac health significantly.

4. Limit Alcohol: Excessive liquor consumption can affect heart rhythm. Therefore, individuals should consume it in moderation.

5. Stress Management: Chronic stress may contribute to heart problems. Techniques like meditation, deep breathing, and exercise can help reduce the same. It also includes getting 7 to 9 hours of sleep every night. 

6. Medication Management: People on medicines that can affect heart rhythm (like beta-blockers) should discuss the potential side effects with their doctor. 

7. Regular Health Check-ups: Getting routine evaluations can help detect problems early, including conditions that might lead to heart block. 

Typically, identification of the condition involves a first-degree heart blockECG to assess the heart. It also includes other key steps. The following is a general outline for the evaluation process:

1. Medical History: The initial step often includes understanding the health history. The doctor will ask the patient about their symptoms, family history of heart disease, and other relevant issues. 

2. Physical Examination: During a thorough vital exam, the healthcare professional will observe the heart and check for signs of cardiac problems.

3. Electrocardiogram (ECG): It is a primary diagnostic tool that records the electrical activity of the heart. It shows disturbances in the sinus rhythm (heartbeat where electrical stimuli begin at the sinus node) and heart structure. The sinus rhythm with 1st-degree AV block shows a prolonged PR interval (greater than 0.20 seconds). This indicates a delay in the electrical conduction from the atria to the ventricles. 

Preparation for Doctor Consultation

Preparing for a health appointment for first-degree heart block involves several steps to ensure the patients get appropriate assessment. The investigative prerequisites include: 

1. Medical Documentation: Compile a detailed health profile, including previous diagnoses, treatments, and surgeries. Note any family history of heart disease or related conditions.

2. Symptoms: Keep a record of the potential symptoms, even if they seem unrelated. This should include their frequency, duration, and what seems to trigger or alleviate them.

3. Current Medications: It is essential to provide a complete list of all ongoing medicines, including over-the-counter drugs and supplements. Some of these can affect heart rhythm or interact with potential treatments for heart block.

4. Enlist Questions: Prepare a list of queries for the doctor. This may revolve around diagnosis, treatment options, lifestyle changes, prognosis, and any further tests or follow-ups required.

5. Support Person: A family member or friend can offer support during the appointment. They can help remember the information provided during the consultation and ask further questions.

Expectations During the Evaluation

During a consultation for first-degree AV block, the doctor may ask various questions to understand the condition better and tailor the treatment plan. These questions may include:

1. Have you experienced symptoms such as shortness of breath, dizziness, or fainting?

2. When did you first notice these symptoms?

3. How often do these symptoms occur, and how long do they last?

4. Does anything seem to improve or worsen these symptoms? 

5. Do you have any other medical conditions, especially heart-related issues?

6. Have you had any previous heart surgeries or procedures?

7. Are you taking any medications, including over-the-counter drugs and supplements?

8. Is there a history of heart disease or related conditions in your family?

9. Do you smoke or consume alcohol? If so, how often?

10. Have your symptoms affected your ability to carry out daily activities or exercise?

Patients should be prepared to answer these questions. 

Questions to Ask the Doctor 

When consulting a doctor about first-degree heart block, it is important to ask questions that help patients understand their condition and the management plan. Here are some key questions individuals might consider asking:

1. Can you explain what first-degree heart block is and how it affects my heart?

2. Is my condition likely to progress or worsen over time?

3. What symptoms should I be aware of or monitor for?

4. Are there any lifestyle changes to help manage my condition?

5. Will I need any treatment or medication for first-degree heart block?

6. Are there any risks or side effects associated with the intervention?

7. What tests will be required to monitor my heart block? 

8. Will I need any special preparations during the diagnostic procedures? 

9. What is the long-term outlook for someone with first-degree heart block?

10. Is there a risk of developing more serious heart conditions?

11. When should I seek immediate medical attention?

Patients should not hesitate to ask any other questions they may have. 

Most cases of first-degree heart block are asymptomatic and do not typically cause significant complications. As a result, they do not require treatment. However, regular evaluation is essential, as patients with it have a higher risk of developing second or third-degree atrioventricular block.

Sometimes, patients may have a PR interval greater than 0.30 seconds and experience symptoms of conduction disorder. In such severe cases, patients may need a permanent pacemaker. This small, battery-powered device sends electrical pulses to the heart.  

A first-degree AV block is generally not serious. Patients can lead normal lives without symptoms, provided the condition does not progress. If the problem worsens, it may cause complications such as: 

1. Injury from Fainting: In AV block, the heart may not pump blood as effectively, which can decrease the blood flow to the brain. This reduction can cause fainting and patients might injure themselves during the fall. 

2. Low Blood Pressure (Hypotension): A slower heart rate can mean less blood is transmitted through the body. This can decrease the blood pressure, leading to dizziness and weakness. 

3. Heart Attack (Myocardial Infarction): In severe cases, it can affect blood flow to a part of the heart. This damages the cardiac muscle and enhances the risk of myocardial infarction. 

4. Internal Organ Damage: Prolonged periods of low blood flow can lead to inadequate oxygenation of the organs. This can damage body parts like the kidneys, brain, and liver.

When to See a Doctor?

Anyone who experiences symptoms of heart block should consult their doctor promptly. Signs that require medical attention include: 

1. Unusual fatigue

2. Difficulty breathing

3. Reduced ability to exercise

4. Feelings of weakness, dizziness, or episodes of fainting 

5. Disorientation or confusion 

For individuals with or at risk of first-degree AV block, a heart-healthy diet is typically recommended. This diet can help manage overall cardiac health and reduce the risk of disease progression. Some key dietary guidelines include:

1. Fruits and Vegetables: These are rich in vitamins, minerals, and fibre and low in calories, which can help maintain a healthy heart. Thus, ensure appropriate consumption of these.

2. Whole Grains: Unlike refined grains they provide more fibre, which can help lower cholesterol and improve cardiovascular health. Examples include oatmeal, brown rice, barley, whole-grain pasta, etc.

3. Low-fat Protein Sources: Lean meats, poultry, fish like salmon, rich in omega-3 fatty acids, low-fat dairy products, and legumes are better protein sources. 

Some foods that must be limited or avoided for a healthy heart include: 

1. Unhealthy Fats: Reducing intake of saturated and trans fats is crucial to lower blood cholesterol along with the risk of heart disease.

2. Salt Intake: Too much sodium can result in high blood pressure. Eating fresh foods and meals cooked at home can help control it significantly.

First-degree heart block is a mild heart rhythm irregularity that is often asymptomatic and usually does not need treatment. It is characterised by a delay in electrical signals in the heart, seen as a prolonged PR interval on an ECG. Regular monitoring is important as it poses minimal risk but can occasionally progress to more serious conditions.

HexaHealth can help you with first-degree AV block by providing access to comprehensive information. Our experts offer consultations to diagnose and manage the disease, promoting heart health. Moreover, we can help you connect with top doctors for regular monitoring and advice. So what are you waiting for? Get in touch with us TODAY! 

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