Impact of ischaemia and scar on the therapeutic benefit derived from myocardial revascularization vs. medical therapy among patients undergoing stress-rest myocardial perfusion scintigraphy.

Abstract

AIMS:

Although pre-revascularization ischaemia testing is recommended, the interaction between the extent of ischaemia and myocardial scar with performance of revascularization on patient survival is unclear.

METHODS AND RESULTS:

We identified 13 969 patients who underwent adenosine or exercise stress SPECT myocardial perfusion scintigraphy (MPS). The percent myocardium ischaemic (%I) and fixed (%F) were calculated using 5 point/20-segment MPS scoring. Patients lost to follow-up (2.8%) were excluded leaving 13 555 patients [35% with history (Hx) of known coronary artery disease (CAD), 65% exercise stress, 61% male, age 66 ± 12]. Follow-up was performed at 12-18 months for early revascularization and at >7 years for all-cause death (ACD) (mean follow-up 8.7 ± 3.3 years). All-cause death was modelled using Cox proportional hazards modelling adjusting for logistic-based propensity scores, MPS, revascularization, and baseline characteristics. During FU, 3893 ACD (29%, 3.3%/year) and 1226 early revascularizations (9.0%) occurred. After risk-adjustment, a three-way interaction was present between %I, early revascularization, and HxCAD, such that %I identified a survival benefit with early revascularization in patients without prior myocardial infarction (MI), whereas no such benefit was present in patients with prior MI (overall model χ(2)= 3932, P < 0.001; interaction P < 0.021). Further modelling revealed that after excluding patients with scar >10% total myocardium, %I identified a survival benefit in all patients.

CONCLUSION:

In this large observational series with long-term follow-up, patients with significant ischaemia and without extensive scar were likely to realize a survival benefit from early revascularization. In contrast, the survival of patients with minimal ischaemia was superior with medical therapy without early revascularization.

• Authors: Rory Hachamovitch, Alan Rozanski, Leslee J Shaw, Gregg W Stone, Louise E J Thomson, John D Friedman, Sean W Hayes, Ishac Cohen, Guido Germano, Daniel S Berman
• Journal: European heart journal (Eur Heart J) Vol. 32 Issue 8 Pg. 1012-24 (Apr 2011) ISSN: 1522-9645 [Electronic] England
• PMID: 21258084 (Publication Type: Comparative Study, Evaluation Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Cardiotonic Agents
• Radiopharmaceuticals
• Technetium Tc 99m Sestamibi

Topics

• Aged
• Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography (methods, mortality)
• Cardiotonic Agents (therapeutic use)
• Cicatrix (complications, diagnostic imaging, mortality)
• Exercise Test
• Female
• Humans
• Kaplan-Meier Estimate
• Male
• Middle Aged
• Myocardial Ischemia (diagnostic imaging, mortality, therapy)
• Myocardial Revascularization (methods, mortality)
• Propensity Score
• Radiopharmaceuticals
• Technetium Tc 99m Sestamibi
• Tomography, Emission-Computed, Single-Photon (methods)
• Treatment Outcome