AV Conduction: Difference between revisions

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 Conduction disturbances can occur at the level of the sinoatrial (SA) node, the atrioventricular (AV) node and the bundle branch system.
-===Sinusbradycardia===
-{{Arrhythmias|
-| name = Sinusbradycardia
-| locatieImage =
-| atrial_frequency = < 60 bpm
-| ventricular_frequency = same
-| regularity = regular
-| origin = sinus node
-| p_wave = normal
-| adenosine = slows down
-| example = Sinusbradycardia of around 40 bpm.[[Image:Rhythm_sinusbradycardia.png|250px|Sinusbradycardia]]
-| example2 =
-}}
-In sinusbradycardia the sinus node fires at a slow (<60 bpm) rate. This can be caused by e.g.: medication (beta-blockers), ischemia (typically inferior myocardial infarction with involvement of the sinus node artery), hypothermia and hypothyroidism. In an athlete a resting heart rate of < 60 bpm often is normal.
-{{clr}}
-===Sinusarrest===
-[[Image:Rhythm_sinusarrest.png|thumb| Sinusarrest. The sinus node stops firing resulting in a pause in heart beats.]]
-During sinus arrest the normal pacemaker cells in the sinus node stop firing. Often an ectopic pacemaker (sometimes from within the sinus node) takes over, but the new rate varies slightly from the old one.
-{{clr}}
-===Asystole===
-During asystole there is no cardiac activity. When prolonged this results in immediate death. Again, asystole is a very unlikely diagnosis in a concious patient and a technical error should be checked first (loose wire, very low gain). Although often called a 'flatliner', the baseline in asystole is often shifting up and down a little and in fact if it isn't (and looks like it is often depicted in movies) a loose wire is the most likely cause.
-{{clr}}
-===Sick Sinus Syndrome===
-In sick sinus syndrome there is a malfunctioning sinus node. Several arrhythmias can result from this:
-* Symptomatic slow sinusbradycardia in the absence of medication
-* Sinusarrest or exit block
-* Combinations of sinoatrial and atrioventricular conductions disturbances
-* Brady-tachycardia syndrome; typically there is sinusbradycardia, sinusarrest or SA-block which is alternated by periods with fast or (ir)regular atrial arrhythmias ([[#atrial fibrillation|atrial fibrillation]], [[#atrial flutter|atrial flutter]], [[#atrial tachycardia|atrial tachyardia]] or [[#sinustachycardia|sinustachycardia]]).
-===Sino-atrial exit block===
-to be filled in
 ===Atrioventricular block===