According to the SMART-CASE study, which was presented during a first report investigation at TCT last week, a conservative strategy of only performing percutaneous coronary intervention (PCI) in lesions with a diameter stenosis of >70% does not increase the risk of all-cause death, myocardial infarction, or any revascularisation at 12 months compared with an aggressive strategy of performing PCI in lesions with a diameter stenosis of >50%.
Principal investigator Hyeon-Cheol Gwon (Department of Internal Medicine, Cardiovascular Center, Seoul National University Hospital, Seoul, South Korea) noted that there is discrepancy between guidelines about when PCI is indicated in an intermediate lesion (diameter stenosis of >50%–70%)—American guidelines recommend that it is indicated where there is a diameter stenosis of >50% but European guidelines recommend it is indicated when there is a diameter stenosis of >70%. He added: “Surprisingly, the clinical outcome of PCI based on the criteria of diameter stenosis of >50% vs. >70% has never been studied.”
Therefore, the objective of the SMART-CASE was to find the optimal strategy of PCI for the angiographically intermediate lesion with the hypothesis that conservative revascularisation using a criterion of >70% diameter stenosis would be non-inferior to aggressive revascularisation using a criterion of >50% diameter stenosis.
In the study, 899 patients with an intermediate stenosis, as identified by quantitative coronary angiography, of >50–70% were randomised to conservative (449) or aggressive (450) PCI. The primary endpoint was a composite of all-cause death, myocardial infraction, or any revascularisation at 12 months. Clinical follow-up was planned at one month, six months, one year, two years, and three years.
At one year, the rate of the primary endpoint was 7.3% in the conservative group vs. 6.8% in the aggressive group (p=0.0055 for non-inferiority). There were no significant differences between the groups in any of the secondary endpoints apart from target lesion revascularisation—4.1% for the conservative strategy compared with 1.7% for the aggressive strategy (p=0.045).
The findings were consistent in most of the subgroups, but there was trend towards favouring aggressive therapy (p=0.07) in patients aged
Gwon concluded: “Conservative revascularisation using a criterion of diameter stenosis of >70% was found to be non-inferior to aggressive revascularisation. The revascularisation of angiographically intermediate lesions can be deferred safely.”