Left ventricular (LV) volumes can be measured using quantitative ventriculography. The LV ejection fraction provides a measure of LV systolic function. Regional systolic wall motion is assessed by grading each segment of the left ventricle as hyperkinetic, normal, hypokinetic,
akinetic, or dyskinetic. Space-occupying lesions might also be identified, if present, within the LV chamber (e.g., thrombus). Stroke volume is determined by subtracting the end-systolic LV chamber volume from the end-diastolic LV chamber volume. Ejection fraction (EF) is the stroke volume divided by the end-diastolic LV volume. Finally, an assessment of mitral valve competence is made. Mitral incompetence (regurgitation) is graded as mild (1+), moderate (2+), moderately severe (3+), or severe (4+).
Typically the left ventriculogram is obtained in one (or ideally two) projections to assess ventricular function. What LV wall segments are assessed in each of the views and how are they graded?
Each segment is graded as hyperkinetic, normal, hypokinetic, akinetic, or dyskinetic.
Right anterior oblique (RAO) projection: Left anterior oblique projection:
1 = Anterobasal 6 = Septal
2 = Anterolateral 7 = Posterolateral.
3 = Apical
4 = Diaphragmatic
5 = Posterobasal
Define coronary dominance.
The nomenclature which describes the coronary artery as dominant can be misleading. It is not simply the degree of importance, but instead identifies the coronary artery which crosses the crux of the heart (junction of the posterior atrioventricular groove with the posterior interventricular groove) and therefore generally supplies the basal posterior interventricular septum of the left ventricle. This same artery commonly gives rise to the atrioventricular nodal artery in the region of, or just beyond, the crux. In approximately 85% of humans, the right coronary artery is dominant. In most of the remaining 15%, the left circumflex artery is dominant; however, codominance‚ does occur.