Cor Vasa 2004, 45(12):601-604

Residual exercise SPECT ischemia in patients with coronary artery disease treated chronically with beta-blockers: a useful tool for selecting high-risk patients

Milan Kamínek^1,*, Jiří Ostřanský², Iva Metelková¹, Miroslav Mysliveček¹, Václav Hušák¹, Otto Lang³

¹ Klinika nukleární medicíny

² I. interní klinika, Fakultní nemocnice a Univerzita Palackého, Olomouc

³ Klinika nukleární medicíny, Fakultní nemocnice Královské Vinohrady a 3. lékařská fakulta Univerzity Karlovy, Praha, Česká republika

The purpose of the study was to assess the prognostic value of exercise SPECT in patients with known coronary artery disease (CAD) treated chronically by beta-blockers. We analyzed 145 patients (63% of men, mean age 57 years) who underwent a symptom-limited bicycle exercise ²⁰¹Tl or ^99mT-MIBI SPECT study without discontinuing beta-blockers. The average heart rate (HR) was 139 beats/min; 71 patients (49%) were unable to reach 85% of the maximal age-predicted HR (group A), while 74 (51%) reached this level (group B). During a mean follow-up of 25 ± 11 months, there were four deaths and six nonfatal myocardial infarctions (MI). Among the 103 patients with normal perfusion, no patient died and two had MI (0.9% per year for cardiac events). An abnormal exercise SPECT finding (n = 42) was associated with a 10-fold increase (9.1 %/year) in the event risk (four deaths and four MI). No significant difference was shown to be related to reaching 85% of the maximal predicted HR. Both in groups A and B, the annual event rates were low in patients with normal exercise SPECT (1.0% versus 0.9%, p = NS), while cardiac event rates were high in patients with an abnormal SPECT (8.0% vs. 10.7%, p = NS). A normal exercise SPECT is associated with an excellent prognosis irrespective achieving 85% of the maximal predicted HR.

Keywords: Myocardial perfusion imaging; Prognosis; Beta-blockers

Published: December 1, 2004  Show citation