Atrioventricular block (AV block) is a type of heart block in which the conduction between the atria and ventricles of the heart is impaired. Under normal conditions, the sinoatrial node (SA node) in the atria sets the pace for the heart, and these impulses travel down to the ventricles. In an AV block, this message does not reach the ventricles or is impaired along the way. The ventricles of the heart have their own pacing mechanisms, which can maintain a lowered heart rate in the absence of SA stimulation.
The causes of pathological AV block are varied and include ischaemia, infarction, fibrosis or drugs, and the blocks may be complete or may only impair the signaling between the SA and AV nodes. Certain AV blocks can also be found as normal variants, such as in athletes or children, and are benign. Strong vagal stimulation may also produce AV block. The cholinergic receptor types affected are the muscarinic receptors.
We researched this topic for you and found the following best online resources. They are categorized into basic, advanced, and research level based on the extent of information you need. You will be taken to the respective websites by pressing on the links below.
Basic information:
http://www.merckmanuals.com/professional/cardiovascular-disorders/arrhythmias-and-conduction-disorders/atrioventricular-block merck manuals (professional version) atrioventricular block
http://www.hrsonline.org/patient-resources/heart-diseases-disorders/heart-block heart rhythm society heart block
https://www.nhlbi.nih.gov/health/health-topics/topics/hb/types national heart lung and blood institute types of heart block
http://my.clevelandclinic.org/services/heart/disorders/arrhythmia/heart-block cleveland clinic heart block
http://www.webmd.com/a-to-z-guides/heart-block-topic-overview web md heart block topic overview
http://www.nhs.uk/conditions/heart-block/pages/introduction.aspx nhs uk heart block
http://www.mountsinai.org/patient-care/health-library/diseases-and-conditions/heart-block-child mount sinai heart block-child
http://www.mayoclinic.org/diseases-conditions/bradycardia/basics/causes/con-20028373 mayoclinic bradycardia causes
https://www.ucsfhealth.org/conditions/complete_heart_block/ ucsf medical center complete heart block
http://www.bupa.co.uk/health-information/directory/h/heart-block bupa heart block
http://en.my-ekg.com/arrhythmias/atrioventricular-blocks.html my ekg atrioventricular blocks (av blocks)
http://www.arrhythmia.org/heartblock.html arrythmias heart block
Advanced information:
http://emedicine.medscape.com/article/151597-overview medscape atrioventricular block
http://ecg.utah.edu/lesson/6 ecg learning center ecg conduction abnormalities
http://lifeinthefastlane.com/ecg-library/basics/wenckebach/ life in the fast lane av block: 2nd degree, mobitz i (wenckebach phenomenon)
http://patient.info/doctor/ecg-identification-of-conduction-disorders patient ecg identification of conduction disorders
http://www.fpnotebook.com/cv/ekg/atrvntrclrblck.htm family practise note book atrioventricular block
http://www.medicalnewstoday.com/articles/180986.php medical news today what is heart block?
http://derangedphysiology.com/files/ecg%20interpretation%20-%203%20-heart%20block.pdf “heart block” – atrioventricular block
http://rarediseases.org/rare-diseases/heart-block-congenital/ national organisation for rare diseases heart block, congenital
http://radiopaedia.org/articles/fetal-complete-atrioventricular-block radiopedia fetal complete atrioventricular block
https://www.uthsc.edu/cardiology/articles/bradycardiaavb.pdf abc of clinical electrocardiography bradycardias and atrioventricular conduction block by david da costa, william j brady, june edhouse bmj volume 324 2 march 2002
http://cdn.intechopen.com/pdfs/13776.pdf pacing therapy in infants and children with congenital and acquired complete atrioventricular block: optimal pacing strategies, management, and follow-up. By floris e.a. Udink ten cate and narayanswami sreeram.
Research:
http://circ.ahajournals.org/content/circulationaha/51/2/226.full.pdf familial atrioventricular heart block an autosomal dominant trait by menashe b. Waxman, m.d.,et al., circulation, volume 51, february 1975
http://www.revespcardiol.org/en/bradyarrhythmias-and-conduction-blocks/articulo/90141585/ bradyarrhythmias and conduction blocks by julia vogler et al., rev esp cardiol. 2012;65:656-67 - vol. 65 num.07 doi: 10.1016/j.rec.2012.01.027
http://onlinelibrary.wiley.com/doi/10.1002/clc.4960120813/pdf clin. Cardiol. 12, 469-472 (1989) mesothelioma of the atrioventricular node and congenital complete heart block by r. Subramanian, b. Flygenri
http://www.scielo.br/scielo.php?pid=s0102-76382011000300010&script=sci_arttext&tlng=en rev bras cir cardiovasc vol.26 no.3 são josé do rio preto july/sept. 2011 http://dx.doi.org/10.5935/1678-9741.20110010 original article:atrioventricular block in the postoperative period of heart valve surgery: incidence, risk factors and hospital evolution by andres di leoni ferrari et al.,
http://www.hindawi.com/journals/cric/2014/372936/ nagham saeed jafar, warkaa al shamkhani, sunil roy thottuvelil narayanan, and anil kumar rajappan, “rapidly progressive atrioventricular block in a patient with sarcoidosis,” case reports in cardiology, vol. 2014, article id 372936, 3 pages, 2014. Doi:10.1155/2014/372936
http://omcr.oxfordjournals.org/content/2014/2/33.full ictal bradycardia and atrioventricular block: a cardiac manifestation of epilepsy by salman s. Allana et al. Oxf med case rep (2014) 2014(2): 33-35.doi: 10.1093/omcr/omu015
http://jmedicalcasereports.biomedcentral.com/articles/10.1186/1752-1947-3-9303 unusual presentation of thyrotoxicosis as complete heart block and renal failure: a case report by suresh krishnamoorthy et al., journal of medical case reports20093:9303 doi: 10.1186/1752-1947-3-9303
http://ijponline.biomedcentral.com/articles/10.1186/1824-7288-38-61 adams-stokes attack as the first symptom of acute rheumatic fever: report of an adolescent case and review of the literature by nicola carano et al., italian journal of pediatrics201238:61 doi: 10.1186/1824-7288-38-61
http://bmccardiovascdisord.biomedcentral.com/articles/10.1186/1471-2261-5-23 ventriculo-atrial gradient due to first degree atrio-ventricular block: a case report by giuseppe ando et al.,bmc cardiovascular disorders20055:23 doi: 10.1186/1471-2261-5-23
http://journal.frontiersin.org/article/10.3389/fphys.2014.00233/full original research article front. Physiol., 25 june 2014 | http://dx.doi.org/10.3389/fphys.2014.00233 acidosis slows electrical conduction through the atrio-ventricular node by ashley m. Nisbet et al.,
Karande s c, sheth s s, dalvi b v, lahiri k, shah m d. Congenital intermittent atrio-ventricular dissociation in tetralogy of fallot (a case report). J postgrad med [serial online] 1991 [cited 2016 aug 1];37:58-61. Available from: http://www.jpgmonline.com/text.asp?1991/37/1/58/798
Dahdouh z, lemaitre a, roule v, troussard v, grollier g. Cardiogenic shock with complete atrio-ventricular block in an octogenarian woman: are we going too far? Oman med j 2014 may; 29(4):299-301. Available from http://www.omjournal.org/fultext_pdf.aspx?detailsid=521&type=fultext
Other articles:
http://www.petmd.com/dog/conditions/cardiovascular/c_dg_atrioventricular_block_complete pet md heart block (complete) in dogs
https://www.vetary.com/dog/condition/heart-block-first the vetary first-degree atrioventricular block in dogs
read more at: https://www.vetary.com/dog/condition/heart-block-first
http://www.vet.cornell.edu/hospital/services/equine/cardiology/conditions/ cornell university college of veterinry medicine cardiology: medical conditions
Related videos:
https://www.youtube.com/watch?v=0pcskwsuvxi atrioventricular block (av block) - types of heart block part 2, animation.
https://www.youtube.com/watch?v=v_tcevif89m major types of heart block
https://www.youtube.com/watch?v=jwvib4t831c ecg heart blocks
https://www.youtube.com/watch?v=f7m-urduede atrioventricular block ( heart block )
https://www.youtube.com/watch?v=-uxfphicysa ecg rhythm review: av blocks
https://www.youtube.com/watch?v=hzrwyfmamb8 1st degree atrioventricular block
https://www.youtube.com/watch?v=pjzcoz7exck second-degree atrioventricular block
https://www.youtube.com/watch?v=negnckc0mrk 3rd degree atrioventricular block