Intravascular red light therapy after coronary stenting - Angiographic andclinical follow-up study in humans

In animal models of coronary restenosis, intravascular red light therapy (I RLT) using a diode laser source has been shown to reduce neointimal hyperpl asia following balloon-induced injury and coronary stenting. We studied the safety and efficacy of catheter-based IRLT for preventing restenosis after coronary stenting in 22 patients with angina pectoris. IRLT was performed using a diode laser (650 nm) at an energy level of 10 megawatts delivered t hrough a rapid exchange balloon system containing the fiberoptics. The proc edure was successful in all patients, with no procedural or in-hospital com plications. Two patients with recurrence of symptoms had angiography at 3 a nd 4.1 months respectively. Angiographic follow-up was also done after 6 mo nths in the 20 remaining asymptomatic patients. The mean minimal lumen diam eter (MLD) for the whole group at 6 months follow-up was 2.57 +/- 0.62 mm. The calculated late lumen loss was 0.49 +/- 1.12 mm with a late loss index of 0.21 +/- 0.54. Four patients (2 symptomatic and 2 asymptomatic) in the s eries developed angiographic restenosis. Clinical events at follow-up of 10 .9 +/- 3.5 months were repeat angioplasty in 2 patients for symptomatic res tenosis with a 91% event free survival. These preliminary results demonstrate that IRLT after coronary artery stent ing is safe and feasible; it is associated with low rates of angiographic i ndices of restenosis.