[Washout rate in patients with hypertrophic cardiomyopathy and hypertensive cardiac hypertrophy].
The present study was performed to clinically clarify the pathogenesis of hypertensive cardiac hypertrophy (HT) and hypertrophic cardiomyopathy (HCM). Exercise thallium-201 (Tl-201) myocardial scintigraphy using a bicycle ergometer was performed for controls, HT and HCM. The scintigrams were evaluated by the circumferential profile analysis. Furthermore, the changes in Tl-201 dynamics in exercise Tl-201 scintigraphy with verapamil injections were examined in these three groups. Analysis of exercise Tl-201 scintigraphy without verapamil injections showed that the initial uptake did not differ among the three groups, but the washout rate three hours after the Tl-201 injections (WR3) did differ among the three groups. Although the WR3 of HT did not differ from that of the controls, the WR3 of HCM was lower than that of the controls. The WR3 with and without verapamil were compared. Although the WR with verapamil injections equalled that without verapamil injections in the controls and HT, the WR3 with verapamil injections decreased more than did that without verapamil injections in HCM. As an index of great and rapid changes in circulation, the washout rate one hour after the Tl-201 injection (WR1) was calculated. The WR1 without verapamil did not differ among the three groups and did not differ from that with verapamil injections in each group. These results suggest that Tl-201 dynamics of HT differ from those of HCM and lowering of the WR3 in HCM may not be caused by disturbance in the microcirculation, but rather by disturbance of Tl-clearance through the cell membrane and its cytoplasm.
Nitta
Y
Y
Second Department of Internal Medicine, School of Medicine, Kanazawa University.
Shimizu
M
M
Kita
Y
Y
Konishi
K
K
Kawagoshi
H
H
Umeda
K
K
Takeda
R
R
Bunko
H
H
Hisada
K
K
Genda
A
A
D006332:Cardiomegaly / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004452:Echocardiography; D005080:Exercise Test; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D006973:Hypertension / Q000150:complications*; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D013794:Thallium Radioisotopes; D014700:Verapamil / Q000494:pharmacology
D013794:Thallium Radioisotopes; D014700:Verapamil