Utilization of excimer laser debulking for critical lesions unsuitable for standard renal angioplasty.

Background: The energy emitted by ultraviolet laser is avidly absorbed in atherosclerotic plaques. Conceptually, it could be applied for debulking of selected atherosclerotic renal artery stenoses. We describe early experience with revascularization of critical renal artery lesions deemed unsuitable for standard renal angioplasty. Institutional Review Board permission to conduct the data analysis was obtained.

Methods: Among 130 percutaneous renal artery interventions with balloon angioplasty and adjunct stenting, there were 12 (9%) patients who underwent laser debulking prior to stenting. These patients presented with critical (95+/-3.5% stenoses) lesions (11 de novo, 1 stent restenosis) deemed unsuitable for standard renal angioplasty because of marked eccentricity and presence of thrombus. Indications for intervention included preservation of kidney function, treatment of uncontrolled hypertension, management of congestive heart failure, and treatment of unstable angina. Blood pressure and estimated glomerular filtration rate (eGFR) were measured pre- and 3 weeks post-intervention.

Results: A baseline angiographic stenosis of 95+/-3.5% was reduced to 50+/-13% with laser debulking. There were no laser-induced complications. Post-stenting the angiographic residual stenosis was 0%. The mean gradient across the lesions was reduced from baseline 85+/-40 to 0 mmHg. A normal post-intervention antegrade renal flow was observed in all patients. Baseline mean systolic BP of 178+/-20 mmHg decreased to 132+/-12 mmHg (P<0.0001) and mean diastolic pressure of 85+/-16 mmHg reduced to 71+/-9 mmHg (P = 0.01). A pre-intervention mean eGFR of 47.7+/-19 ml/min/1.73 m(2) increased to 56+/-20.4 ml/min/1.73 m(2) (P = 0.05) post-procedure. The interventions were not associated with major renal or cardiac adverse events. During follow-up one patient developed transient contrast-induced nephropathy.

Conclusions: Debulking of select renal artery stenoses with laser angioplasty followed by adjunct stenting is feasible. Further prospective, randomized studies will be required to explore the role of debulking and laser angioplasty in renal artery revascularization.