The evaluation of left ventricular eccentric hypertrophy by 201Tl-myocardial scintigraphy

In order to elucidate the mechanism of left ventricular eccentric hypertrophy in conditions of volume overload, Tl-201 myocardial scintigraphy was performed in patients with aortic valve regurgitation and mitral valve regurgitation. There was a good relationship between the severity of Tl-defects, as determined by Tl-201 myocardial scintigraphy, and the changes in the T wave on the ECG on the one hand and the NYHA functional classification of heart diseases. In 17 of 18 patients where LVDd increased with increasing severity of Tl-defects and the defects were moderate to severe, LVDd was 65 mm or larger. There was a significant negative correlation between the washout rate for the whole circumference of the left ventricle, as determined by exercise Tl-201 SPECT, and LVDd (r=-0.603, p<0.01). The phenomenon of redistribution as determined by exercise Tl-201 myocardial scintigraphy was observed relatively early. Our results suggest that mechanical volume overload and ischemic changes are involved in left ventricular wall damage in left ventricular eccentric hypertrophy. For patients with moderate to severe Tl-defects valve replacement is indicated, no matter whether they may have heart failure or arrhythmia. (author)