Heart Block

Also found in: Dictionary, Thesaurus, Medical, Legal, Financial, Acronyms, Wikipedia.
Related to Heart Block: Complete heart block, First degree heart block, Second degree heart block

heart block

[′härt ‚bläk]
The cardiac condition resulting from defective transmission of impulses from atrium to ventricle.

Heart Block


disruption of the conductivity of the nerve impulse along the conductive system of the heart. Types of heart blocks—intra-auricular (sinoauricular) blocks, au-riculoventricular (atrioventricular) blocks, and blocks of the peduncles of the bundle of His and of the terminal branches—are distinguished depending on the site of the disruption. Heart block may be caused by organic diseases of the myocardium (rheumocarditis, coronary cardiosclerosis), more rarely by intoxications, and also by functional disturbances of the nervous system (neuroses). It may be temporary or permanent, complete or partial. Bradycardia (slowing of the pulse to 18–10 beats per minute) is noted in cases of complete heart block; this leads to severe anemia of the brain accompanied by dizziness, loss of consciousness, and sometimes convulsions. Treatment is directed at eliminating the causes of the heart block.


References in periodicals archive ?
What is the suspected mechanism of congenital heart block resulting from anti-Ro antibodies?
The symptoms may come on gradually or suddenly and they typically include: Palpitations (an awareness of having an irregular, abnormal or a heavy heartbeat) Light-headedness and loss of consciousness if the heart stops beating completely Shortness of breath | Chest pain If it's left untreated, complete heart block may lead to acute heart failure, chronic heart failure, stroke, shock and even death.
The Royal Brompton Hospital has previously fitted a pacemaker to five-day-old King Britton when he too was diagnosed with heart block during his mother's pregnancy.
An additional 35 patients will be needed for the second phase of the study, which will proceed if fewer than 3 of the 19 women in the first phase have children with second- or third-degree heart block.
Second-degree heart block occurs when some of the electrical signals from the upper chamber of the heart, called the atrium, don't reach the lower chamber, which is called the ventricle.
Bradycardia or heart block may manifest in patients both with and without known underlying cardiac conduction abnormalities.
Unfortunately, treatment of autoimmune fetal heart block is unproven.
Spain and Cathcart (4) described a 59-year-old woman with complete heart block who at necropsy had "almost the entire myocardium [in the upper third of the ventricular septum] .
Liza Morton, 35, was born with a congenital heart block and was the youngest patient fitted with the device.
Liam had already defied medical odds as doctors thought he would not survive 15 minutes past his birth because of a congenital heart block.
The electrocardiogram (ECG) showed a first degree heart block with a widened ORS complex with O waves and ST elevation in leads I, 11, III, aVF and V1-4 (Figure 1), suggestive of possible acute myocardial infarction.
Pineau noted that anti-Ro antibodies, present in approximately one-third of patients with lupus, are known to be associated with the development of irreversible heart block in 1%-2% of neonates whose mothers carry the autoantibodies.