Original title: Clinical and Procedural Predictors of Suboptimal Outcome After the Treatment of Drug-Eluting Stent Restenosis in the Unprotected Distal Left Main Stem The Milan and New-Tokyo (MITO) Registry. Reference: Circ Cardiovasc Interv. 2012;5: 491-498

We have very little data on the percutaneous treatment of restenosis of an unprotected LMCA. 

The aim of this study was to evaluate the optimum strategy of angioplasty for restenosis in patients with bifurcation of LMCA and to see if the initial strategy affected the later outcome. Lesions were considered significant when at least 50%.

The primary endpoint was a composite of death, myocardial infarction and target lesion revascularization (MACE).

Between 2002 and 2008, 575 patients underwent angioplasty following an unprotected LMCA with a pharmacological stent (DES) in two high-volume centers. Of these, 92 developed restenosis with compromised bifurcation. In 8 patients we opted for the CABG and the remaining 84 had a new angioplasty, (43 patients balloon angioplasty and 41 a new DES).The average age of the population was 65.5 ± 9.5 years, 46.4% were diabetic, 41.7% received a stent and 58.3% two stents. Clinical follow-up was performed on all patients (mean 24 months) and an angiography on 91.7%.

The primary endpoint (MACE) occurred in 31 patients (36%). The new revascularization (TLR) was more frequent when we used a balloon only and a new DES (47.6 ± 7.7% versus 20.8 ± 6.6% respectively RR 4.14, 95% CI, 1.21-14.25, P = 0.02) and this was independent of type and location of the original restenosis. Treatment with balloon and a EuroSCORE > 6 were the only independent predictors of TLR. 

Circumflex ostium restenosis was observed in 41 patients, (44.6%), but only 9 patients had angina, in the rest the diagnosis was made by angiographic tracking. No patient with circumflex ostium restenosis died during follow-up to 2 years. The technique of two stents in the initial procedure had the largest and most recurrent restenosis compared with the one stent technique. The initial technique can predict the risk of restenosis but only for the region of the ostium Cx.

Conclusion 

The study suggests that patients with restenosis of LMCA benefit more if treated with a new DES than with a balloon only. Complex lesions requiring two stents are initially associated with higher incidence of restenosis and re-restenosis, especially in the ostium Cx.

Editorial Comment:

The small population and lack of randomization were limiting, although it seems safe and effective to perform angioplasty of LMCA whenever a new DES is also needed, not just the balloon. It is interesting to ask whether it is necessary to treat all restenosis at ostium Cx because no events were observed clinically when tracked to two years but on the other hand it is the most common site of restenosis. The use of one or two stents, both at the initial procedure and in the treatment of restenosis, was at the discretion of the surgeon and may have been influenced by the anatomical complexity. Whether the higher restenosis was due to the initial anatomy, the use of a stent or a combination of two is difficult without randomization. 

https://solaci.org/es/pdfs/mito_registry.pdf
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