Differential effects comparing exercise and pharmacologic stress on left ventricular function using gated Tc-99m sestamibi SPECT.
OBJECTIVE
Although post-ischemic stunning has emerged as an important marker for severe coronary artery disease (CAD), differences in stress methods may have different effects on left ventricular (LV) volumes and function.


METHODS
To assess differential effects comparing exercise and pharmacologic stress on the LV measurements, (99m)Tc-sestamibi gated single-photon emission computed tomography (SPECT) acquired more than 30 min after stress and at rest was evaluated in 38 patients undergoing adenosine triphosphate (ATP) stress (ATP group) and 38 age-and sex-matched patients subjected to exercise stress (Ex group) among 268 patients with normal SPECT findings.


RESULTS
Coronary risk factors and LV volumetric measurements at baseline were similar in the two groups. Compared with volumetric measurements at rest, end-diastolic volume (EDV) increased (72 +/- 21 ml to 74 +/- 21 ml; P = 0.01), end-systolic volume increased (25 +/- 12 ml to 28 +/- 13 ml; P = 0.001), and ejection fraction (EF) decreased after stress (66% +/- 8% to 63% +/- 9%; P < 0.002) in the ATP group. In the Ex group, by contrast, no such change was observed. In addition, changes in EDV (3 +/- 6 vs. -1 +/- 5 ml; P = 0.01) and the stress-to-rest ratio of EDV (1.04 +/- 0.09 vs. 0.99 +/- 0.08; P < 0.02) after stress were greater in the ATP than in the Ex group.


CONCLUSIONS
Differential effects of stress methods on LV volumes persist more than 30 min after the stress. These findings should be kept in mind when interpreting post-ischemic stunning.
Ohtaki
Yuka
Y
Department of Cardiology, Tokyo Medical University, 6-7-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo, Japan.
Chikamori
Taishiro
T
Igarashi
Yuko
Y
Hida
Satoshi
S
Tanaka
Hirokazu
H
Hatano
Tsuguhisa
T
Usui
Yasuhiro
Y
Miyagi
Manabu
M
Yamashina
Akira
A
D000255:Adenosine Triphosphate / Q000009:adverse effects*; D000368:Aged; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology; D005080:Exercise Test / Q000009:adverse effects*; D005260:Female; D015637:Gated Blood-Pool Imaging; D006801:Humans; D008297:Male; D016555:Matched-Pair Analysis; D008875:Middle Aged; D017682:Myocardial Stunning / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology*; D019275:Radiopharmaceuticals; D012146:Rest; D012189:Retrospective Studies; D013312:Stress, Physiological / Q000209:etiology / Q000503:physiopathology; D013318:Stroke Volume; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon; D016277:Ventricular Function, Left / Q000187:drug effects
D019275:Radiopharmaceuticals; D000255:Adenosine Triphosphate; D017256:Technetium Tc 99m Sestamibi