Related Experiment Videos
Analysis of left ventricular wall movement during isovolumic relaxation and its relation to coronary artery disease
Insights
Abnormal inward wall movement during isovolumic relaxation in patients with ischaemic heart disease indicates local ischemia. This finding significantly impacts overall left ventricular function during both systole and diastole.
Area of Science:
- Cardiology
- Cardiac Imaging
- Physiology
Background:
- Left ventricular (LV) function assessment is crucial in ischaemic heart disease (IHD).
- Understanding diastolic function, particularly isovolumic relaxation, is key to evaluating LV mechanics.
- Abnormalities in wall motion during diastole may indicate underlying myocardial ischemia.
Purpose of the Study:
- To investigate regional left ventricular wall movement abnormalities during isovolumic relaxation in patients with IHD.
- To differentiate normal wall motion patterns from those indicative of ischemia.
- To assess the impact of abnormal wall motion on overall LV function.
Main Methods:
- Digitization of left ventricular angiograms from 60 IHD patients and 10 normal subjects.
- Frame-by-frame analysis of regional wall movement throughout the cardiac cycle.
- Quantification of wall movement distances and velocities during isovolumic relaxation and filling phases.
Main Results:
- Normal subjects exhibited symmetrical outward wall movement (1.5–3.0 mm) during isovolumic relaxation.
- IHD patients showed abnormal inward movement in affected areas and compensatory outward movement in unaffected areas.
- Abnormal cavity shape changes and reduced peak wall movement rates were observed in IHD patients.
Conclusions:
- Inward wall movement during isovolumic relaxation is an abnormal finding and a marker of local myocardial ischemia.
- This diastolic abnormality significantly affects both systolic and diastolic left ventricular function in IHD.
- The study highlights the diagnostic value of analyzing wall motion during isovolumic relaxation for detecting and characterizing ischemia.
Abstract:
Left ventricular angiograms of 60 patients with ischaemic heart disease and 10 normal subjects were digitized frame by frame in order to study abnormalities of wall movement during the period of isovolumic relaxation. Plots were made of regional wall movement around the cavity throughout the cardiac cycle. In normal subjects 1-5 to 3-0 mm of symmetrical outward wall movement occurred during isovolumic relaxation, associated with an apparent increase of left ventricular volume of 10 +/- 4 per cent. The corresponding peak velocities of wall movement were 4-3 to 5-7 cm/s, significantly less than those recorded in the same region of the cavity after mitral valve opening. In patients with ischaemic heart disease, the following abnormalities were encountered: (1) Abnormal inward movement, which, in single coronary artery disease, occurred in the area supplied by the affected vessel. (2) Abnormal outward movement of more than 6 mm in non-affected areas which appeared to be a compensatory phenomenon. (3) An abnormal cavity shape change towards a more circular configuration before mitral valve opening. (4) Reduced peak rates of wall movement in affected areas during systole and filling. It is concluded that such inward wall movement during isovolumic relaxation is abnormal and a sign of local ischaemia whose presence has significant effects on overall left ventricular function in both systole and diastole.