| systolic gradient | The difference in pressure during systole between two communicating cardiovascular chambers, e.g., between the left ventricle and aorta in aortic stenosis. (05 Mar 2000) |
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| electrochemical gradient | A measure of the tendency of an ion to move passively from one point to another, taking into consideration the differences in its concentration and in the electrical potentials between the two points; commonly expressed as the additional voltage needed to achieve equilibrium. (05 Mar 2000) |
| ficoll gradient | A density gradient of ficoll (synthetic sucrose polymer) in solution, where concentration of the ficoll varies continuously through the solution. It is often used to separate different types of cells from each other during the process of sedimentation. (09 Oct 1997) |
| field gradient | In magnetic resonance imaging, a magnetic field that varies with location, superimposed on the uniform field of the magnet, to alter the resonant frequency of nuclei and allow recovery of their spatial position. Synonym: field gradient. (05 Mar 2000) |
| 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) |
| 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) |