Bradycardia

Diagnosis

The diagnosis of bradycardia often begins with discussing the symptoms, inquiring about the medical history, and performing a physical examination. A physical examination entails inspecting the body for apparent symptoms of conditions or issues. To help with the diagnosis, the doctor may use a stethoscope to listen to the heart.

• Blood tests:
  • Electrolyte Levels: These tests assess the concentration of electrolytes, particularly calcium, potassium, and magnesium, in your bloodstream.
  • Thyroid Hormone Levels: Bradycardia can be caused by hypothyroidism, which is characterized by low thyroid function. Testing thyroid hormone levels helps determine if this condition is contributing to the slow heart rate.
  • Troponin: Troponin is a specific protein found in the cells of your heart muscle. If there is damage to these cells, troponin can be released into the blood, indicating potential heart damage. Troponin levels are a critical factor used by healthcare providers to diagnose heart attacks.
  • Toxicology Screen: This test is conducted to identify toxic substances present in your blood. It can detect drugs, both prescription and recreational, that may lead to bradycardia, as well as other substances that can cause damage to the heart.
• Electrocardiogram (ECG or EKG): An ECG is a primary diagnostic test for bradycardia, a condition characterized by a slow heart rate. It measures the heart’s electrical activity by placing sticky patches called electrodes on the chest, and sometimes on the arms and legs. These electrodes are connected to a computer, which displays the results. Through an ECG, it is possible to determine if the heart is beating too slowly, too rapidly, or not at all.

However, since an ECG can only detect bradycardia if the slow heartbeat occurs during the test, a portable ECG device may be recommended by healthcare providers. There are two types of portable ECG devices commonly used:

• • Holter monitor: This device can be carried in a pocket or worn on a belt or shoulder strap. It continuously records the heart’s activity for 24 hours or longer.
  • Event recorder: Similar to a Holter monitor, this device records the heart’s activity but only at specific times for a few minutes each time. It is worn for a longer duration than a Holter monitor, typically 30 days. When symptoms occur, the user usually presses a button to record the activity. Some devices can automatically detect and record irregular heart rhythms.

These portable ECG devices are crucial for diagnosing bradycardia because they allow for precise tracking of the heart’s electrical activity over an extended period. By using multiple sensors, known as electrodes, which adhere to the skin of the chest, they can detect and display the heart’s electrical activity as a waveform on either a paper printout or a computer screen.

Other tests may be requested along with ECG, such as:

• • Tilt table test: A tilt test is used to determine whether a change in position produces fainting. During the test, the table is tilted as if one were standing up while lying flat on it. The result of this test can assist the doctor comprehend how the bradycardia produces fainting spells.
  • Stress exercise test: This test is done while being active. A medicine that stimulates the heart in a manner similar to exercise may be administered to those with difficulties exercising. Normally, the ECG is performed while riding a stationary bicycle or walking on a treadmill, to monitor the activity of the heart.
  • Sleep study: If your healthcare provider suspects that bradycardia is being caused by recurrent interruptions in breathing during sleep (known as obstructive sleep apnea), they may suggest a sleep study.

Treatment

Treatment is usually not required when bradycardia is not causing any symptoms. Generally, treatment options may include medication, implanted device, and lifestyle changes. If bradycardia occurs due to another medical issue, treating that illness may be all that is needed to stop bradycardia.

The appropriate treatment is usually determined by the severity of the symptoms as well as the reason for the slow heart rhythm.

• Medications: If bradycardia is causing severe issues like dangerously low blood pressure, medical interventions such as intravenous (IV) or injectable medications like atropine can be used to increase heart rate. These treatments are typically administered in a hospital setting due to the need for monitoring and additional care for individuals receiving these medications. Alternatively, there are oral medications available that can be taken daily to enhance heart function, including increasing the strength of heart contractions or regulating heart rate.
• Surgery or other procedures:
  • Temporary pacing: Utilizes a device with electrical contacts that make contact with or attach to the skin of the chest. These contacts enable a gentle electrical current to enter the body and stimulate the heart to beat. Temporary cardiac pacing is an effective short-term treatment for individuals requiring a permanent pacemaker or those experiencing a brief period of bradycardia.
  • Permanent pacemaker: Is often the most effective treatment for individuals with bradycardia, particularly those with sick sinus syndrome, where the heart’s natural pacemaker cells are not functioning properly. While a permanent pacemaker cannot completely cure this condition, it provides a long-term solution by effectively managing it. Pacemakers typically have a lifespan of several years, with some models having batteries that can last over a decade. The process of receiving a permanent pacemaker involves a surgical procedure to implant the device, which delivers electrical pulses to the heart muscle. An electrophysiologist or surgeon creates a small pocket beneath the skin to accommodate the pacemaker. They then connect wires, known as leads, to various points on the heart.

New advancements in medical technology have made it possible to avoid surgery in certain cases where a pacemaker implantation is needed for bradyarrhythmia. Instead of undergoing a traditional surgical procedure, patients now have the option of receiving a newer type of pacemaker called a leadless pacemaker. This innovative device can be implanted using a catheter-based procedure, which involves the insertion of a tube-like catheter through a small incision made in a major blood vessel. The catheter is carefully guided up to the heart, where the pacemaker is directly implanted. These leadless pacemakers are incredibly small, comparable in size to a large multivitamin pill. Moreover, this minimally invasive approach allows for a shorter hospital stay, enabling patients to return home sooner than they would after traditional surgery.