Evaluation of myocardial function with the 201thallium scintimetry in various diseases of the heart. A correlative study based on 100 patients.

To assess the validity of the quantitative 201Tl scintimetry in various diseases of the heart (coronary heart disease with and without myocardial infarction, non-coronary cardiomyopathy, scleroderma heart disease and asymmetric septal hypertrophy with IHSS), the 201Tl myocardial uptake values for five standardized projections (a) were correlated with the grade of LAD stenosis, (b) the pattern of myocardial wall motion and (c) were compared with the 201Tl uptake values derived from normal patients. Significant reduction (c) of 201Tl myocardial uptake could in individual cases be evaluated in acute myocardial infarction (95%), in dys- and akinesia (90%), in hypokinesia (71%), in scleroderma heart disease (50%), in non-coronary cardiomyopathy (50%) as well as in normokinesia (28%) when associated with LAD stenosis. The mean values (b) of 201Tl uptake in normo- and hypokinesia significantly differed between these two groups and from those evaluated in dys- and akinesia. The latter group showed the lowest 201Tl uptake values computed which in some cases were very close to the mean mediastinal 201Tl uptake. The correlation (a) of individual 201Tl values demonstrated that 201Tl distribution in the myocardium is not only equivalent to myocardial ""perfusion'' but is corresponding with the myocardial function. In non-coronary cardiomyopathy reduced 201Tl values sometimes could not be separated from values in coronary heart disease (and myocardial infarction). A regional increase of myocardial mass as in septal hypertrophy correlated well with an augmented 201Tl uptake when referred to the 201Tl storage in the mediastinum.