Comparison of the short-term survival benefit associated with revascularization compared with medical therapy in patients with no prior coronary artery disease undergoing stress myocardial perfusion single photon emission computed tomography.
BACKGROUND
The relationship between the amount of inducible ischemia present on stress myocardial perfusion single photon emission computed tomography (myocardial perfusion stress [MPS]) and the presence of a short-term survival benefit with early revascularization versus medical therapy is not clearly defined.


RESULTS
A total of 10 627 consecutive patients who underwent exercise or adenosine MPS and had no prior myocardial infarction or revascularization were followed up (90.6% complete; mean: 1.9+/-0.6 years). Cardiac death occurred in 146 patients (1.4%). Treatment received within 60 days after MPS defined subgroups undergoing revascularization (671 patients, 2.8% mortality) or medical therapy (MT) (9956 patients, 1.3% mortality; P=0.0004). To adjust for nonrandomization of treatment, a propensity score was developed using logistic regression to model the decision to refer to revascularization. This model (chi2=1822, c index=0.94, P<10-7) identified inducible ischemia and anginal symptoms as the most powerful predictors (83%, 6% of overall chi2) and was incorporated into survival models. On the basis of the Cox proportional hazards model predicting cardiac death (chi2=539, P<0.0001), patients undergoing MT demonstrated a survival advantage over patients undergoing revascularization in the setting of no or mild ischemia, whereas patients undergoing revascularization had an increasing survival benefit over patients undergoing MT when moderate to severe ischemia was present. Furthermore, increasing survival benefit for revascularization over MT was noted in higher risk patients (elderly, adenosine stress, and women, especially those with diabetes).


CONCLUSIONS
Revascularization compared with MT had greater survival benefit (absolute and relative) in patients with moderate to large amounts of inducible ischemia. These findings have significant consequences for future approaches to post-single photon emission computed tomography patient management if confirmed by prospective evaluations.
Hachamovitch
Rory
R
Department of Imaging, Cedars-Sinai Medical Center, University of California Los Angeles School of Medicine, Los Angeles, Calif 90048, USA.
Hayes
Sean W
SW
Friedman
John D
JD
Cohen
Ishac
I
Berman
Daniel S
DS
D000241:Adenosine; D000368:Aged; D002317:Cardiovascular Agents / Q000627:therapeutic use*; D003327:Coronary Disease / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy*; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D015999:Multivariate Analysis; D009204:Myocardial Revascularization; D011379:Prognosis; D016016:Proportional Hazards Models; D016019:Survival Analysis; D017256:Technetium Tc 99m Sestamibi; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon
D002317:Cardiovascular Agents; D013794:Thallium Radioisotopes; D017256:Technetium Tc 99m Sestamibi; D000241:Adenosine