Interest in the use of drug-eluting balloons for applications beyond in-stent restenosis seems to be building in the United States. Since it has been used for a decade outside the U.S., this might be an example of America last. In any case it is here and although exorbitantly expensive I am told that it is highly reimbursed, so it will be used. The idea of nothing left behind is foreign to most American interventional cardiologists who long ago replaced the term “angioplasty” with the word “stenting.” They have never done angioplasty without a stent. If the stent is to be left out of a procedure, what will the operators need to learn from angioplasty?

I will come to some of the considerations including case and lesion selection, risk factors for acute complications and restenosis, and some of the technique-altering methods we studied when “angioplasty” without stents was a thing. But first, why is this old idea of leaving no metal device behind gaining so much new interest? Stents have served us well, but longitudinal studies show a continuing late event rate of about 2 % per year. Some have nothing to do with the stent, but in-stent restenosis or neoatherosclerosis remains the indication for about 10 % of percutaneous interventions, so stenting is not perfect.

The mechanism of healing from balloon injury or stenting is very different. Angioplasty creates deep fissures in the artery wall, and most neointima grows in those areas. Stenting causes an injurious irritation around the circumference of the vessel as well as a chronic strain on the wall and neointima formation is much more extensive. Stents work because they cause and initially sustain a larger lumen without significant recoil. It is understandable that one might like to get by without having to scaffold the artery with a stent, but scaffolding is frequently needed because of recoil. Overcoming that recoil with a balloon alone without causing catastrophic acute complications was the challenge of angioplasty before stenting. I was recently asked to give a talk for SCAI on what we learned about angioplasty in the old days that might be applicable today. This, perhaps inappropriate, invitation to “teach new dogs old tricks” sent me to look again through studies our group performed in the 80s regarding angioplasty methods and outcomes. Most of practice evolved from experience but systematic observations, registries, and some randomized control trials also informed us. Early balloons had a low pressure burst rating so as new ones came out, we tested higher pressure inflations. This did result in larger lumen and less stenosis and pressure gradient across the lesion. Larger balloons were tested versus smaller ones. Oversized balloons resulted in more dissections and need for emergency surgery bailout. We saw that longer balloon inflations were associated with better acute results. This was tested with perfusion of hyperoxygenated compounds that could be infused through the central lumen of the balloon and later by using flow through perfusion balloons. It is disturbing to see the ultra-short balloon inflations used today, even though they can be partially offset by placing a stent. Pressure gradients measured after balloon deflation are a good indicator of how well the lesion had been dilated and observation of that gradient over 10–15 min could predict good or bad outcomes due to recoil of the vessel. Of all these observations, the one perhaps most interesting in the preparation of the artery for drug-coated balloon use is the impact of dissection. Whereas we found that acute complications occurred in 9 % of the arteries that had post procedure dissections, the restenosis rate was significantly less when visible dissections were present. Our observations had to be made with angiography and fluid-filled catheter pressure measures. There was no IVUS, OCT, or accurate pressure measures such as FFR or IFR. Today an adequate angioplasty result should be more reliably assessed. And if absent, stenting is always available.

A study in this issue of CRM raises the question of whether the use of drug-coated balloons is better than drug-eluting stents for vessels less than 3 mm in size. The Swedish National registry, SCAAR, was used to compare drug-coated balloons and drug-eluting stents with propensity matching methods [1]. The authors compared 1439 pairs of drug-coated balloon and drug-eluting stent treated lesions over an 8-year period with an average follow up of 3.5 years. Target vessel revascularization of 7.7 % in the drug coated balloon group was not less than the 5.1 % in the drug-eluting stent group. The accompanying editorial pointed out that this registry may not reflect current outcomes when intravascular imaging and more vigorous lesion preparation is employed [2]. They point out that a recent meta-analysis, ANDROMEDA, of four randomized trials showed a more encouraging assessment of the benefit of drug coating balloon use [3].

Recently the Academic Research Consortium published definitions and endpoints to be used in various types of clinical trials [4]. Since the hypothesis that leaving stents out of the artery may lead to long-term benefit, trials will have to be very long term to show superiority for most conditions. For some situations, the desire for something other than stents is strong, especially for side branch lesions and diffuse small vessel disease. Will drug-coated balloon angioplasty be better than leaving them alone? Trials will be performed but some questions will likely remain unanswered. Practice will evolve as always, mostly from individual experiences. There may be lessons to be learned from our experience before stents, and those of us who lived through that trauma will be glad to give advice. In addition to intravascular imaging mine will be: make sure you crack (dissect) the artery, relieve the translesional pressure gradient, leave the lesion preparation balloon inflated a long time (not just the drug-coated balloon), wait (at least 10 min) before you place the drug-coated balloon, and if you are worried, stent it.