Abstract

Objectives: To assess the accuracy of real-time myocardial contrast perfusion imaging (MCPI) for the diagnosis of restenosis and extent of coronary artery disease (CAD) in patients with previous percutaneous coronary intervention (PCI).

Methods: 56 patients were studied 1.9 (SD 1.4) years after PCI. They underwent MCPI with commercially available ultrasound contrast agents (Optison or Definity) at rest and at peak dobutamine–atropine stress. Coronary angiography was performed within one month. Significant CAD was defined as ⩾ 50% stenosis in ⩾ 1 major epicardial coronary artery. Significant restenosis was defined as ⩾ 50% stenosis in a coronary segment with previous intervention.

Results: Reversible perfusion abnormalities were detected in 40 of 43 patients with significant CAD and in 4 of 13 patients without (overall sensitivity 93%, 95% CI 85% to 99%; specificity 69%, 95% CI 44% to 94%; and accuracy 88%, 95% CI 79% to 96%). Significant restenosis in ⩾ 1 coronary artery with previous PCI was detected in 38 (68%) patients. Reversible perfusion abnormalities were present in 35 of them (sensitivity 92%, 95% CI 84% to 99%). Reversible perfusion abnormalities were detected in ⩾ 2 vascular distributions in 20 of 28 patients with multivessel CAD and in 3 of 28 patients without (sensitivity 71%, 95% CI 55% to 88%; specificity 89%, 95% CI 78% to 99%; and accuracy 80%, 95% CI 70% to 91%). Restenosis was detected in 41 coronary arteries. Sensitivity of MCPI for regional diagnosis of restenosis was 73% (95% CI 60% to 87%), specificity was 75% (95% CI 60% to 90%), and accuracy was 74% (95% CI 64% to 84%).

Conclusion: Dobutamine stress MCPI is a useful technique for the evaluation of restenosis and extent of CAD after PCI.