| 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) |
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| 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) |
| ventricular | <anatomy> Pertaining to a ventricle. (18 Nov 1997) |
| ventricular aberration | Abnormal intraventricular conduction of a supraventricular beat, especially where surrounding beats are normally conducted. Synonym: ventricular aberration. (05 Mar 2000) |
| ventricular afterload | Formerly, the arterial pressure or some other measure of the force that a ventricle must overcome while it contracts during ejection, contributed to by aortic or pulmonic artery impedance, peripheral vascular resistance, and mass and viscosity of blood; now, more rigorously expressed in terms of the wall stress, i.e., the tension per unit cross-sectional area in the ventricular muscle fibres (calculated by an expansion of Laplace's law utilizing pressure, internal radius, and wall thickness) that is required to produce the intracavitary pressure required during ejection. (05 Mar 2000) |
| ventricular aneurysm | Aneurysm of the ventricular portion of the membranous septum, an aneurysm that bulges toward the right in systole, often consisting of the anterior leaflet of the tricuspid valve. Synonym: cardiac aneurysm. (05 Mar 2000) |
| ventricular arrhythmia | <cardiology> A cardiac arrhythmia which originates from within the ventricles. Isolated ventricular contractions are referred to as premature ventricular contractions. Frequent premature ventricular contractions can be potentially unstable and can degrade to a more serious rhythm or cardiac arrest. (12 Jan 1998) |
| ventricular arrhythmias | 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) |
| ventricular arteries | Branches of the right and left coronary arteries distributed to the muscle of the ventricles. Synonym: arteriae ventriculares. (05 Mar 2000) |
| ventricular assist device | A device that supports or replaces the function of a ventricle (LVAD or RVAD indicates which ventricle). The patient's heart remains in place when this device or system is used. The device is used in patients with potentially salvageable myocardium, where centrifugal or pneumatic devices can be placed in either heterotopic or orthotopic positions (the latter is termed a total artificial heart). The function of either the left, right, or both ventricles can thus be supported for days to weeks. Either recovery of heart function or need for transplantation then becomes apparent. (05 Mar 2000) |
| ventricular band of larynx | One of the pair of folds of mucous membrane stretching across the laryngeal cavity from the angle of the thyroid cartilage to the arytenoid cartilage; they enclose a space called the rima vestibuli or false glottis. Synonym: plica vestibularis, false vocal cord, plica ventricularis, ventricular band of larynx, ventricular fold. (05 Mar 2000) |
| ventricular bigeminy | Paired ventricular beats, the common form consisting of ventricular extrasystoles coupled to sinus beats. (05 Mar 2000) |
| ventricular bradycardia | Slowness of ventricular rate, usually implying the presence of atrioventricular block. (05 Mar 2000) |
| ventricular capture | Capture of the ventricle(s) by an impulse arising in the atria or A-V junction. (05 Mar 2000) |
| ventricular complex | The continuous QRST waves of each beat in the electrocardiogram. (05 Mar 2000) |