Elsevier

Journal of Nuclear Cardiology

Volume 11, Issue 5, September–October 2004, Pages 542-550
Journal of Nuclear Cardiology

Incremental prognostic value of left ventricular function by myocardial ECG-gated FDG PET imaging in patients with ischemic cardiomyopathy

https://doi.org/10.1016/j.nuclcard.2004.07.005Get rights and content

Background

The purpose of this study was to determine the independent value of left ventricular (LV) functional parameters derived from gated fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) to predict prognosis in patients with ischemic cardiomyopathy undergoing myocardial viability assessment.

Methods and results

We studied 90 consecutive patients with coronary artery disease and low LV ejection fraction (26% ± 7%) undergoing gated FDG PET to assess myocardial viability for potential revascularization. The primary endpoint for this analysis was the occurrence of cardiac death, myocardial infarction, or worsening heart failure (HF) to New York Heart Association class IV. During follow-up (22 ± 14 months), 21 patients had an event (17 died, 4 had myocardial infarctions, and 4 had worsening HF). On Cox regression analysis, the event-free survival rate at 2 years was lower for patients with an end-diastolic volume (EDV) of 260 mL or greater (relative risk, 2.7; P = .014), end-systolic volume (ESV) of 200 mL or greater (relative risk, 2.5; P = .021), and LV mass of 143 g or greater (relative risk, 1.6; P = .009). In a risk-adjusted model, EDV (χ2 = 68, P < .0001) and ESV (χ2 = 75, P = .035) added a significant amount in the estimation of events over the perfusion-FDG mismatch pattern (χ2 = 40, P < .001). In a stratified Cox model, patients with PET mismatch, LV ejection fraction lower than 25%, and EDV of 260 mL or greater had the lowest survival rate (P = .006). These patients showed an apparent survival benefit with revascularization but without an improvement in HF symptoms.

Conclusion

LV functional parameters determined by gated FDG PET have incremental prognostic value over viability information in patients with ischemic cardiomyopathy. Our data suggest that patients with residual viability and advanced cardiac remodeling are at high clinical risk. In these patients the apparent survival benefit of revascularization may not be associated with a measurable improvement in HF symptoms.

Section snippets

Patient population

The population studied was selected from a cohort of 137 consecutively tested patients between January 1995 and April 1999 undergoing rest myocardial perfusion and ECG-gated FDG metabolism PET studies in the assessment of myocardial viability for potential myocardial revascularization. Of the original 137 patients, 47 were excluded: 27 because of imaging issues (technical problems in 16 and no images available in 11) and 20 with LVEF greater than 40%. Finally, 90 patients with documented CAD

Baseline characteristics of patients

Patients enrolled in this study had advanced coronary heart disease. All patients had significant coronary artery stenosis and previous myocardial infarction (Table 1). In addition, more than 25% of the population had cardiac surgery, hypertension, or heart failure. The mean LVEF by gated FDG PET was 26% ± 7%. A total of 38 patients exhibited a perfusion-metabolic mismatch pattern, whereas 52 patients had a match pattern between perfusion and metabolism.

Clinical outcomes

During the follow-up period (mean, 22 ±

Discussion

This study revealed that, in a population with severely reduced LVEF due to CAD referred for myocardial viability testing, measures of LV remodeling (ie, LV volumes and mass) have incremental prognostic value over the perfusion-metabolism PET mismatch pattern in predicting cardiac events. In a risk-adjusted Cox model, the 2-year event-free survival rate was consistently higher for patients with relatively preserved LVEF as well as heart size and mass compared with those with severely reduced

Acknowledgment

Some of the authors (E.V.G. and T.L.F.) receive royalties from the sale of the Emory Cardiac Toolbox related to the research described in this article. The terms of this arrangement have been reviewed and approved by Emory University in accordance with its conflict-of-interest practice. The other authors have indicated they have no financial conflicts of interest.

References (34)

  • R.O. Bonow

    Myocardial viability and prognosis in patients with ischemic left ventricular dysfunction

    J Am Coll Cardiol

    (2002)
  • A. Yamaguchi et al.

    Left ventricular volume predicts postoperative course in patients with ischemic cardiomyopathy

    Ann Thorac Surg

    (1998)
  • E.V. Garcia et al.

    Assessment of mechanical function as an adjunct to myocardial perfusion/metabolism emission tomography studies

    J Nucl Med

    (1994)
  • R.C. Marshall et al.

    Identification and differentiation of resting myocardial ischemia and infarction in man with positron computed tomography 18F-labeled fluorodeoxyglucose and N-13 ammonia

    Circulation

    (1981)
  • J. Tillisch et al.

    Reversibility of cardiac wall-motion abnormalities predicted by positron tomography

    N Engl J Med

    (1986)
  • J.E. Udelson

    Steps forward in the assessment of myocardial viability in left ventricular dysfunction

    Circulation

    (1998)
  • M. Di Carli et al.

    Quantitative relation between myocardial viability and improvement in heart failure symptoms after revascularization in patients with ischemic cardiomyopathy

    Circulation

    (1995)
  • Cited by (0)

    Funded in part by the National Institutes of Health; National Heart, Lung, and Blood Institute grant Nos. K01 HL70422 and R01 HL68904; and the 2001 American Society of Nuclear Cardiology/Fujisawa Award for Basic or Applied Scientific Research in Nuclear Cardiology.

    View full text