Quantification of regional left ventricular function by magnetic resonance in patients with reversible myocardial ischaemia

Cine magnetic resonance imaging [cine MRI] has advantages over other methods of assessing regional ventricular function. The endocardium and epicardium are readily defined and myocardial thickness and thickening can be measured. These are important parameters for assessing myocardial viability and conditions such as stunning and hibernation. We have assessed myocardial thickness, thickening, and motion, we have established normal ranges for circumferential profiles in four planes, and we have compared the parameters with myocardial perfusion in patients with coronary artery disease. We studied 20 normal volunteers and 14 patients with coronary artery disease. Thirteen patients had reversible perfusion abnormalities by thallium tomography and 5 had fixed defects. Cine magnetic resonance images were acquired in the vertical and horizontal long axis and in basal and apical short axis planes. The endocardium and epicardium were defined manually at end diastole and end systole and circumferential profiles of diastolic wall thickness, systolic thickening, and wall motion were generated. Categories for each variable were assigned in each of 9 segments according to the number of standard deviations from the mean of the normal group. One hundred and twenty six segments were assessed. There was good agreement between the categories of wall motion [normal, hypo-, akinetic] and myocardial perfusion [normal, reversible, and fixed defect], differing by one category or less in 121 segments [96%, K[w] = 0.5]. The agreement between categories of wall thickening and perfusion was moderate [75% agreement, k[w] = 0.42]. The agreement between coronary anatomy and both wall motion and wall thickening was good [82%, k[w] = 0.31 and 78%, k[w] = 0.6 respectively]. We conclude that cine magnetic resonance imaging provides an objective method of assessing myocardial motion, thickness and thickening and that there is agreement between these assessments of function and myocardial perfusion and coronary anatomy

Regional left ventricular function in patients with hot technetium 99M thyroid scan

In this work, 17 hyperthyroid patients underwent technetium 99m thyroid scan after stoppage of treatment for two weeks were studied. The development of enhanced left ventricular systolic and diastolic function in patients with hyperthyroidism was consistent with a direct trophic effect of thyroid hormone on the myocardium. Technetium 99m thyroid scan was a valuable measure in expecting early alterations in diastolic left ventricular function which might be affected before the systolic one