Laser coronary angioplasty: history, present and future.

The efficacy of percutaneous transluminal coronary angioplasty (PTCA) is limited by remaining plaque tissue and the development of restenosis. It has been demonstrated that the restenosis rate is low if a large lumen diameter is achieved after coronary intervention. Debulking of coronary stenoses is a concept to increase the luminal diameter after intervention. Laser angioplasty debulks coronary stenoses by ablation of atherosclerotic plaque. Since the first intravascular laser intervention, the technique has been significantly improved by the use of optimized wavelength, the development of flexible optimally spaced multifiber catheters and an additional saline flush technique. These technical advancements allowed a reduction in the incidence of adverse events, such as the number of dissections and perforations, associated with the use of the laser technique. Coronary laser angioplasty is commonly combined with adjunctive balloon angioplasty to optimize the outcome. Laser coronary angioplasty was not followed by a lower restenosis rate compared with plain balloon angioplasty in lesions without stents, however, a randomized comparison of the techniques including the use of the saline flush technique is not available yet. The value of excimer (acronym for excited dimer) laser coronary angioplasty for treatment of in-stent restenosis is still under investigation. So far, nonrandomized single center studies have not suggested a relevant benefit for this technique used for in-stent restenosis. In nonstented lesions there remain niche indications for laser angioplasty such as the treatment of ostial lesions, diffuse lesions or lesions traversable with a guidewire but not with an angioplasty balloon. Laser coronary angioplasty may also be useful after a failed balloon angioplasty and in patients with chronic total occlusions. The potential advantages of combining laser coronary angioplasty with vaporization of thrombus in patients with acute coronary syndromes are currently under evaluation.

Laser angioplasty: historical perspective.

Serious interest in laser angioplasty began in the early 1980s in an attempt to solve two of the primary limitations of balloon angioplasty, recanalization and restenosis. By demonstrating the ability of laser irradiation to vaporize atherosclerotic tissue, it was logical to hypothesize that this powerful tool may allow recanalization of lesions that could not be crossed by conventional guidewire and balloon technology. With refinements in laser fibreoptics and catheter delivery systems, several laser systems were approved for clinical use as recanalization devices in both peripheral and coronary arteries. However, the requirement to follow laser angioplasty with conventional balloon angioplasty in the majority of cases and the lack of an effect of laser tissue removal (debulking) on restenosis has limited a broader acceptance of this technology. Perhaps improved techniques discussed later in this series such as saline infusion and better fibreoptic-lens systems will allow laser angioplasty to offer a true niche in interventional cardiology.