Coronary Artery Disease
Long-term prognostic value of duke treadmill score and exercise thallium-201 imaging performed one to three years after percutaneous transluminal coronary angioplasty

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Abstract

The value of exercise nuclear perfusion imaging performed beyond the 6-month restenosis window for percutaneous transluminal coronary angioplasty (PTCA) has not been explored. This study evaluates the long-term prognostic value of exercise thallium (Tl)-201 imaging after PTCA. We studied the late outcome of a series of 211 patients with tomographic Tl-201 exercise studies performed between 1 to 3 years after PTCA. Follow-up was 96% complete at a median duration of 7.3 years. Most (73%) had 1- or 2-vessel coronary artery disease and normal left ventricular function and 193 (91%) had successful PTCA. Two thirds of the patients were symptomatic at the time of testing. The mean Duke score was 5 ± 6 and 125 (60%) patients had a low-risk Duke score. Mean summed stress score was 50 ± 9 and mean summed reversibility score was 3 ± 4. The 5-year overall survival was 95%, yielding a low annual mortality rate of 1%/year. The summed stress score exhibited a significant association (p = 0.047) with the end point of cardiac death or myocardial infarction. The Duke score was predictive of the combination end point of hard and soft cardiac events (p = 0.002). This study demonstrates that exercise Tl-201 perfusion imaging performed 1 to 3 years after PTCA was predictive of cardiac events.

Section snippets

Study group

The study population was retrospectively identified from the Mayo Clinic Nuclear Cardiology Laboratory database and the Mayo Clinic PTCA Registry. Patients were eligible for the study if they: (1) performed an exercise tomographic Tl-201 test between January 1, 1989, through December 31, 1991, and (2) had undergone PTCA between 1 and 3 years preceding the Tl-201 study. Patients were excluded for the following reasons: (1) technically poor images; (2) left bundle branch block or paced

Exercise Tl-201 imaging (Table II)

The mean Duke score was 5 ± 6; 125 (60%) of the study group had a low-risk Duke score and 81 (39%) had normal Tl-201 images. Most patients had evidence of exercise-induced ischemia: 84 (40%) developed angina or had a positive electrocardiogram, and 114 (54%) had at least 1 reversible Tl-201 segment. The mean summed stress score was 50 and the mean summed reversibility score was 3. Exercise Tl-201 variables associated with a very poor prognosis were present in relatively few patients. Only 1%

Long-term event rate after PTCA

The low event rates in this study were comparable to other series of PTCA patients,6, 7, 8 indicating that patients post-PTCA generally are a low-risk population. Seventy-three percent of the study population had 1- or 2-vessel disease, similar to anatomic findings in large PTCA series.5, 6, 7, 8, 9

Follow-up of patients after PTCA

Standard treadmill testing early after PTCA for purposes of identifying restenosis is of limited usefulness due to low sensitivity and inability to localize ischemia.22 The Duke score was derived

References (25)

  • D.R. Holmes et al.

    Restenosis after percutaneous transluminal coronary angioplasty (PTCA)a report form the PTCA registry of the National Heart, Lung and Blood Institute

    Am J Cardiol

    (1984)
  • K. Detre et al.

    Has improvement in PTCA intervention affected long-term prognosis? The NHLBI PTCA registry experience

    Circulation

    (1995)
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