health care  
 
All about heart block first degree heart block second degree heart block third degree or complete heart block causes of heart block symptoms of heart block diagnosis of heart block treatments for heart block arrhythmias (abnormal heart rhythms) {bundle branch block cardiac arrhythmia atrial fibrillation atrial flutter supraventricular tachycardia sick sinus syndrome ventricular arrhythmias ventricular tachycardia ventricular fibrillation heart block Brugada syndrome long QT syndrome short QT syndrome Wolff-Parkinson-White syndrome (WPW syndrome)}

What is first degree heart block?

First-degree heart block, or first-degree AV block, is when the electrical impulse moves through the AV node more slowly than normal. The time it takes for the impulse to get from the atria to the ventricles (the PR interval) should be less than

about 0.2 seconds. If it takes longer than this, it's called first-degree heart block.

First degree heart block is a disease of the electrical conduction system of the heart. In first degree heart block, the disease is almost always at the level of the atrioventricular node (AV node). In normal individuals, the AV node slows the conduction of electrical impulse through the heart. This is manifest on a surface EKG as a prolongation of the PR interval. The normal PR interval is from 120 ms to 200 ms in length. In first degree heart block, the diseased AV node conducts the electrical activity slower. This is seen as a PR interval greater than 200 ms in length on the surface EKG. Isolated first degree heart block has no clinical consequences. There are no symptoms or signs associated with it, and there is no danger of progression to complete heart block.

In a subset of individuals with the triad of first degree heart block, right bundle branch block, and either left anterior or left posterior fascicular block (known as trifascicular heart block) may be at an increased risk of progression to complete heart block.

More information on heart block

What is heart block? - Heart block is a disorder of the heartbeat. Heart block is common in elderly people as their hearts have undergone degenerative changes.
What's first degree heart block? - First-degree heart block, or first-degree AV block, is when the electrical impulse moves through the AV node more slowly than normal.
What's second degree heart block? - Second degree heart block is a disease of the electrical conduction system of the heart. There are two distinct types of second degree heart block.
What's third degree or complete heart block? - Third degree heart block, also known as complete heart block, is a disease of the electrical system of the heart.
What causes heart block? - Heart block has a variety of causes. It can sometimes be a result of a congenital defect. It can also occur after a heart attack or as a result of myocarditis.
What are the symptoms of heart block? - The main symptom associated with heart block is fainting (syncope). Second degree heart block may not cause symptoms.
How is heart block diagnosed? - Heart blocks can be diagnosed with a test called an electrocardiogram (ECG), which measures the heart's electrical activity.
What're the treatments for heart block? - First-degree heart block requires no treatment even when it is caused by heart disease. A temporary pacemaker may be used in an emergency.
Heart & cardiovascular disorders Mainpage

Topics in heart disease and cardiovascular disorders

Coronary circulation disorders
Myocardium disorders
Heart valve disorders
Arrhythmias (abnormal heart rhythms)
Heart inflammation and infection
Congenital heart disease
Valvular disease (blood vessels disorders)
Procedures done for coronary artery disease
Devices used in cardiology
Diagnostic tests and procedures for heart diseases
Heart transplant
 

Featured articles on heart disease and cardiovascular disorders

Coronary artery disease
Heart attack (myocardial infarction)
Atherosclerosis
Cardiomyopathy
Cardiac arrhythmia
Heart valve replacement
Congestive heart failure
Aortic aneurysm
Atrial fibrillation
Stroke


All information is intended for reference only. Please consult your physician for accurate medical advices and treatment. Copyright 2005, health-cares.net, all rights reserved. Last update: July 18, 2005