Salvatore Cassese (Deutsche Herzzentrum, Technische Universität and DZHK, partner site Munich Heart Alliance, Munich, Germany) and others report in the European Heart Journal that the four-year mortality rate is significantly higher in patients with evidence of restenosis at routine control angiography than patients without evidence of restenosis. They add that the rate is significantly increased even in restenosis patients who are asymptomatic.
Cassese et al state that guideline-writing authorities and appropriate-use criteria only recommend control angiography after coronary stenting for patients reporting anginal symptoms or those presenting with signs of ischaemia, which they explain is because previous studies have shown that there are “no benefits in terms of long-term survival” with the use of routine control angiography. However, they add that other studies have indicated that patients with angiographically proved restenosis at routine surveillance are associated with a worse prognosis at long-term follow-up. “Given the lack of definite conclusions, we sought to investigate the prognostic role of restenosis in a large broadly inclusive population undergoing routine control angiography after percutaneous coronary intervention (PCI) with stenting,” the authors comment.
In the study, Cassese et al reviewed data for patients who underwent routine control angiography after PCI with stenting between 1998 and 2009 at two tertiary referral centres in Munich (routine control angiography was standard clinical practice at these timepoints in these centres).They assessed the incidence of restenosis, the rate of target lesion revascularisation in patients with restenosis, and the mortality rate at four years after the angiography (the primary outcome).
Of 10,004 patients (with 15,004 treated lesions) identified, 2,643 (26.4%) had evidence of restenosis at routine control angiography (performed at an average of 198.5 days after PCI). The four-year mortality rate was significantly increased in patients with restenosis than those without restenosis—9.6% vs. 8.3%, respectively (p=0.03). Also, evidence of restenosis at routine control angiography was found to be an independent risk factor for death at four years (p=0.02). The authors report that evidence of restenosis was an independent risk factor for death at four years even in asymptomatic patient with restenosis (p=0.01) and that the four-year mortality rate was significantly increased in these patients compared with asymptomatic patients without restenosis (9.2% vs. 7%, respectively; p=0.02).
Of the patients with restenosis, Cassese et al found that 62.5% of them underwent target vessel revascularisation but that there were no significant differences in the four-year mortality rate between those who underwent target vessel revascularisation and those who did not—9% vs. 10%, respectively (p=0.43). The authors comment: “A higher rate of repeat revascularisation is recognised to be the principal tradeoff of routine control angiography and it is important to exclude the potential adverse impact of repeat revascularisation in patients presenting with angiographic restenosis.” They add that the study’s finding that there were no differences in the mortality rate between those who underwent target vessel revascularisation and those who did not “speaks against a negative influence of repeat revascularisation at the time of control angiography on subsequent mortality risk out to four years.”
Concluding, Cassese et al say that their results indicate that evidence of restenosis provides “prognostic information complementary to that provided by other relevant clinical characteristics [eg. age].”
Study author Adnan Kastrati (Deutsche Herzzentrum, Technische Universität and DZHK, partner site Munich Heart Alliance, Lazarettstrasse, Germany) told Cardiovascular News: “Intuitively—in an observational study—patients with more severe restenosis and, consequently, with a higher cardiovascular risk profile were more likely to undergo target vessel revascularisation. Therefore, it is no surprise to see that it had no effect on mortality. While no one would disagree with the need of target vessel revascularisation in symptomatic patients with angiographic restenosis, the issue of the prognostic benefit of the procedure in asymptomatic patients requires specifically designed randomised trials. I am sceptical, however, about the chances of such a trial being done.”