| BBBB | Bilateral Bundle Branch Block |
|---|---|
| RBBB | Right Bundle Branch Block |
| BB | bad breath; bed bath; beta blockade, beta blocker; BioBreeding [rat]; blanket bath; blood bank; bloo... |
| BBB | blood-brain barrier; blood buffer base; bundle-branch block |
| BBBB | bilateral bundle-branch block |
| atrioventricular canal cushions | A pair of mounds of embryonic connective tissue covered by endothelium, bulging into the embryonic atrioventricular canal; located one dorsally and one ventrally, they grow together and fuse with each other and with the lower edge of the septum primum, dividing the originally single canal into right and left atrioventricular orifices. Synonym: endocardial cushions. (05 Mar 2000) |
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| atrioventricular conduction | Forward conduction of the cardiac impulse from atria to ventricles via the A-V node or any bypass tract, represented in the electrocardiogram by the P-R interval. P-H conduction time is from the onset of the P wave to the first high frequency component of the His bundle electrogram (normally 119 ± 38 msec); A-H conduction time is from the onset of the first high frequency component of the atrial electrogram to the first high frequency component of the His bundle electrogram (normally 92 ± 38 msec); P-A conduction time is from the onset of the P wave to the onset of the atrial electrogram (normally 27 ± 18 msec). (05 Mar 2000) |
| atrioventricular conduction abnormalities | <cardiology, physiology> Any condition which involves abnormal (blocked, delayed or aberrant) electrical conduction through the atrioventricular node (for example atrioventricular block). Some medications may precipitate atrioventricular conduction abnormalities. (02 Jan 1998) |
| atrioventricular connections | The five distinct and discrete ways in which the atrial chambers may be connected to the ventricles are concordant, discordant, ambiguous, double inlet, and univentricular. (05 Mar 2000) |
| atrioventricular dissociation | Any situation in which atria and ventricles are activated and contract independently, as in complete A-V block, more specifically, the dissociation between atria and ventricles that results from slowing of the atrial pacemaker or acceleration of the ventricular pacemaker at nearly equal (rarely equal) rates, each depolarising its own chamber, thus interfering with depolarisation by the other (interference-dissociation). (05 Mar 2000) |
| atrioventricular extrasystole | An extrasystole arising from the "junctional" tissues, either the A-V node or A-V bundle. Synonym: junctional extrasystole. (05 Mar 2000) |
| atrioventricular gradient | The diastolic pressure difference between the atrium and ventricle. (05 Mar 2000) |
| atrioventricular groove | A groove on the outer surface of the heart marking the division between the atria and the ventricles. Synonym: sulcus coronarius, atrioventricular groove, atrioventricular sulcus, auriculoventricular groove, coronary sulcus. (05 Mar 2000) |
| atrioventricular interval | The time between depolarisation of the atria and of the ventricle. Synonym: atrioventricular interval. (05 Mar 2000) |
| atrioventricular junctional bigeminy | Paired beats, each pair consisting of an A-V nodal extrasystole coupled to a beat of the dominant, usually sinus, rhythm. Synonym: nodal bigeminy. (05 Mar 2000) |
| atrioventricular junctional rhythm | The cardiac rhythm when the heart is controlled by the A-V junction (including node); arising in the A-V junction, the impulse ascends to the atria and descends to the ventricles, each at varying speeds depending on site of the pacemaker. Synonym: A-V junctional rhythm, nodal bradycardia, nodal rhythm. (05 Mar 2000) |
| atrioventricular junctional tachycardia | Tachycardia originating in the A-V junction. Synonym: A-V junctional tachycardia, nodal tachycardia. (05 Mar 2000) |
| atrioventricular nodal extrasystole | A premature beat arising from the A-V junction and leading to a simultaneous or almost simultaneous contraction of atria and ventricles. (05 Mar 2000) |
| atrioventricular node | <cardiology> The location in the heart's conduction system, between the atria and the ventricles, which conducts the normal electrical impulse from the atria to the ventricles. (27 Sep 1997) |
| atrioventricular septum | The small part of the membranous septum of the heart just above the septal cusp of the tricuspid valve that separates the right atrium from the left ventricle. Synonym: septum atrioventriculare, pars membranacea septi atriorum. (05 Mar 2000) |