Influence of hypertensive left ventricular hypertrophy on detection of ischemic area with exercise thallium-201 myocardial scintigraphy]

Sixty-four patients with single left anterior descending artery disease having effort angina (group A: 40 patients without hypertension, group B: 10 patients with hypertrophic hypertension, group C: 14 patients with non-hypertrophic hypertension) were assessed the influence of hypertensive left ventricular (LV) hypertrophy on detection of ischemic area. The criterion of hypertrophy by two-dimensional echocardiography was > 12 mm in the wall thickness of interventricular septal or posterior wall. Population in Group B might show low detectability in ischemic area by 201Tl myocardial scintigraphy (positive thallium rate 60%, defect score 2.7 +/- 3.6), and high lung thallium uptake and high frequence of ECG positive among three groups. In semiquantitative analysis, the washout rate of the posterolateral wall and %RD (delayed %uptake-initial %uptake) of the septal wall in patients with Group B were lowest among three groups. However, the washout rate in the septal wall against the posterior wall, and the initial %uptake and the delayed %uptake of the septal wall were not significantly different among three groups. We could conclude that the decreased washout rate in nonischemic area with hypertensive LV hypertrophy might make the ischemic area masked.