伊藤 創

Two patients after Kawasaki disease (KD) developed acute myocardial infarction in their thirties, though coronary artery follow-up were deemed unnecessary because of apparently angiographic normal coronary arteries in their children more than 1-year after acute KD. Angiographic findings of apparently normal coronary arteries in the late period after acute KD are possible to mislead their prognoses. It should be recognized that coronary aneurysms can often regress in the late period. There is ongoing controversy about the therapeutic strategy in patients whose coronary aneurysms regressed within several years after acute KD. Coronary computed tomography angiography and flow-mediated dilatation might be useful for the detection of mild sequelae of KD non-invasively.

We previously reported that serial coronary computed tomography angiography (CTA) had a potential to evaluate the interval change of plaque morphology of coronary arteries. The aim of this study was to evaluate variables associated with the plaque progression by serial CTA. We included 148 patients (age 66.3 +/- 9.8 years, male 81.1 %, median scan interval 12 months) with coronary artery disease undergoing serial CTA. Each coronary artery was compared visually between baseline and follow-up CTA to detect plaque progression. Baseline characteristics between progression and nonprogression patients did not demonstrate any significant differences. Logistic analysis revealed that only low-density lipoprotein cholesterol (LDL-C) a parts per thousand yen100 mg/dl at follow-up was associated with plaque progression (odds ratio 2.59, 95 % confidence interval 1.12-6.34, P = 0.0263). Cutoff value of LDL-C for plaque progression at follow-up was 103.0 mg/dl based on receiver-operator characteristic curves analyses. Of the 36 progressive lesions in 32 patients, plaque composition at baseline included 13 lesions (36.1 %) of noncalcified plaque, 1 lesion (2.8 %) of calcified plaque, 12 lesions (33.3 %) of partially calcified plaque, and the remaining 10 lesions (27.8 %) had no plaque at baseline and revealed de novo plaques at follow-up. There were 9 lesions (25 %) with high-risk plaque (HRP) characteristics at baseline and 18 lesions (50 %) with HRP at follow-up. Plaque progression of coronary arteries by serial CTA was associated with LDL-C a parts per thousand yen100 mg/dl at follow-up regardless of baseline LDL-C level. There was no specific finding to predict plaque progression on the baseline plaque characteristics.

Objective To study the usefulness of combined risk stratification of coronary CT angiography (CTA) and myocardial perfusion imaging (MPI) in patients with previous coronary-artery-bypass grafting (CABG). Design A retrospective, observational, single centre study. Setting and patients 204 patients (84.3% men, mean age 68.77.6) undergoing CTA and MPI. Main outcome measures CTA defined unprotected coronary territories (UCT; 0, 1, 2 or 3) by evaluating the number of significant stenoses which were defined as the left main trunk 50% diameter stenosis, other native vessel stenosis 70% or graft stenosis 70%. Using a cut-off value with receiver-operating characteristics analysis, all patients were divided into four groups: group A (UCT=0, summed stress score (SSS)<4), group B (UCT1, SSS<4), group C (UCT=0, SSS4) and group D (UCT1, SSS4). Results Cardiac events, as a composite end point including cardiac death, non-fatal myocardial infarction, unstable angina requiring revascularisation and heart-failure hospitalisation, were observed in 27 patients for a median follow-up of 27.5months. The annual event rates were 1.1%, 2%, 5.7% and 12.9% of patients in groups A, B, C and D, respectively (log rank p value <0.0001). Adding UCT or SSS to a model with significant clinical factors including left ventricular ejection fraction, time since CABG and Euro SCORE II improved the prediction of events, while adding UCT and SSS to the model improved it greatly with increasing C-index, net reclassification improvement and integrated discrimination improvement. Conclusions The combination of anatomical and functional evaluations non-invasively enhances the predictive accuracy of cardiac events in patients with CABG.