We have read with a particular attention the letter titled “More stent, more troubles” by Dinesch and Buruian where they, commenting our case report , argue the lack of scientific evidence to support the treatment of chronic total occlusion (CTO).

Percutaneous treatment of a CTO is not a mere exercise of technical skill. In fact the presence of a CTO is associated with an increased short and long-term mortality in the setting of acute myocardial infarction with and without ST segment elevation . A meta-analysis of 13000 patients enrolled in observational registries demonstrated that the recanalization of a CTO was associated with a significant reduction of both mortality and major adverse cardiovascular events in comparison with a failed procedure .

But if the relationship between the efficacy of CTO recanalization and the improvement of prognosis would not be enough, patients with a successful CTO-PCI were more frequently free of angina at 6-year compared with patients in whom CTO-PCI was ineffective . In two prospective registries the revascularization of a CTO was associated with a better quality of life in comparison with medical therapy . For this purpose, we want to underline that dyspnea and reduced exercise tolerance are the main symptoms that are very frequently reported by patients with a CTO, while classical angina is described only by a minority of them.

Apart from this, it is well known that every CTO determines myocardial ischemia. In fact, in a series of consecutive CTOs, fractional flow reserve measured distally to the occluded segment was less than 0.80, indicating a significant myocardial ischemia which is not influenced by the degree of collateral circulation . The good development of collateral circulation is generally considered one of the main reasons to leave the patient under medical therapy. However the good development of collateral circulation is not able to prevent from ischemia during exercise . For this purpose in patients with a CTO and well developed coronary collaterals, aggressive revascularization, either with PCI or with coronary artery bypass graft, reduced the risk of mortality and of major adverse cardiovascular events in comparison with medical therapy alone .

Obviously the benefit of CTO-PCI is as increased as the ischemic area is more extensive . In the COURAGE trial, an important selection bias was evident and patients with left main disease, coronary occlusion, refractory angina, severe left ventricular dysfunction were excluded. Moreover one third of patients in the medical therapy arm underwent to PCI, whereas, in the PCI arm, drug-eluting stents were used only in 2.7% of total PCI . This scenario derived from COURAGE trial does not reflect the actual real world. In a further subanalysis of COURAGE, the benefit of percutaneous treatment compared with optimal medical therapy was greater in patients with an ischemic burden >10% . The same results were obtained by Hachamovitch and coworkers more than 10 years ago .

Moreover among chronic occlusions, in stent restenosis-CTO (ISR-CTO) represent a subgroup where the procedural success is lower than conventional CTO. In this setting the implantation of multiple stents is very frequent and IVUS is very useful to optimize the PCI results and to promptly recognize the problems (e.g. stent underexpansion or malapposition, incomplete coverage of disease) that could trigger a new target vessel revascularization.

Finally we would suggest that CTO-PCI should be performed by dedicated operators in each center. However if the CTO is very complex or the operator is not so expert, the patient should be referred to a specialized center.

Last, at 15 months clinical follow-up our patient was completely asymptomatic and he resumed a normal life without any physical limitation. Echocardiogram was normal (EF=65%). He told us that CTO-PCI has dramatically improved his quality of life. His gratitude represents the most important stimulus to continue with our daily work.