| epidural block | An obstruction in the epidural space; used inaccurately to refer to epidural anaesthesia. (05 Mar 2000) |
|---|---|
| exit block | Inability of an impulse to leave its point of origin, the mechanism for which is conceived as an encircling zone of refractory tissue denying passage to the emerging impulse. (05 Mar 2000) |
| fascicular block | A condition based on the concept that the left branch of the bundle of His provides two of three major fascicles of a system of conduction, of which the right bundle branch constitutes the third, for the transmission of the cardiac impulse from the atrium above to the ventricles below the A-V node; block may occur in any or all fascicles, all three together producing complete A-V block. See: hemiblock. (05 Mar 2000) |
| unidirectional block | Block that prevents passage of an impulse when it approaches from one direction but not from the other, as when block in the A-V node prevents anterograde conduction to the ventricles while retrograde conduction to the atria remains intact. (05 Mar 2000) |
| field block | Regional anaesthesia produced by infiltration of local anaesthetic solution into tissues surrounding an operative field. (05 Mar 2000) |
| field block anaesthesia | Conduction anaesthesia in which small nerves are not anaesthetised individually, as in nerve block anaesthesia, but instead are blocked en masse by local anaesthetic solution injected to form a barrier proximal to the operative site. (05 Mar 2000) |
| first degree A-V block | See: atrioventricular block. (05 Mar 2000) |
| fish-block | See Fish-tackle. Source: Websters Dictionary (01 Mar 1998) |
| local nerve block | Infiltration of a local anesthetic around a peripheral nerve so as to produce anesthesia in the area supplied by the nerve. (16 Dec 1997) |
| aberrant ventricular conduction | Abnormal intraventricular conduction of a supraventricular beat, especially where surrounding beats are normally conducted. Synonym: ventricular aberration. (05 Mar 2000) |
| aortico-left ventricular tunnel | Congenital connection between the aorta above exit of coronary arteries and the left ventricle. (05 Mar 2000) |
| arrhythmias, ventricular | Abnormal rapid heart rhythms (arrhythmias) that originate in the lower chambers of the heart (the ventricles). Ventricular arrhythmias include ventricular tachycardia and ventricular fibrillation. Both are life threatening arrhythmias most commonly associated with heart attacks or scarring of the heart muscle from previous heart attack. (12 Dec 1998) |
| arrhythmogenic right ventricular dysplasia | A congenital cardiomyopathy in which transmural infiltration of adipose tissue results in weakness and aneurysmal bulging of the infundibulum, apex, and posterior basilar region of the right ventricle and leads to ventricular tachycardia arising in the right ventricle. (12 Dec 1998) |
| atrial ventricular canal defect | A defect caused by deficient or absent septal tissue immediately above and below the normal level of the atrioventricular valves, including the region normally occupied by the A-V septum in hearts with two ventricles. The A-V valves are abnormal to a varying degree. (05 Mar 2000) |
| bidirectional ventricular tachycardia | Ventricular tachycardia in which the QRS complexes in the electrocardiogram are alternately mainly positive and mainly negative; many such cases may represent ventricular tachycardia with alternating forms of aberrant ventricular conduction. (05 Mar 2000) |