Background: Some lesions can be very difficult to reach, especially if acute angles and/or multiple turns "protect" access. Once reached, the guiding system needs to give sufficient support for balloons or stents to be deployed.
Methods: A "telescopic" system was created consisting of: (1) a microcatheter with guidewire. This system fits into any catheter allowing a 0.035 inch wire. (2) a 4Fr "delivery" catheter. (3) If sharp angles were encountered, the 4Fr catheter was deployed through a 6Fr or larger angulated guiding sheath. This was cut-off 15 cm out of the groin and re-valvulated with a standard short introducer sheath.
Patients and results: Since 2004, 89 microcatheter telescopic systems were used during a 4-year period in 1,225 procedures (7.3%). The technique allowed probing with a floppy steerable and exchangeable guidewire, securing any gained position as well as exchanges with a stiffer guide wire if required. Procedures where the telescopic system was effective included: complex stenoses e.g. aortopulmonary collaterals (n = 21), tortuous ducts (n = 9), anterograde balloon dilation of critical aortic stenosis (n = 8) and crossing Blalock Taussig shunts (n = 3). Once in place, the telescopic system allowed delivery of embolic material (n = 38), balloon angioplasty (n = 21), stent deployment (n = 23), fulguration of pulmonary valve (n = 1) or introduction of medication (n = 1). The interventionalists felt that using the telescopic system had reduced fluoroscopy and procedure time.
Conclusions: The microcatheter-telescopic system is an invaluable tool to reach difficult targets and allows exchange for suitable guidewires permitting balloons, stents, embolisation material or radiofrequency energy to be deployed in such targets. This approach has become our standard when dealing with difficult targets protected by a tortuous route.
Copyright 2009 Wiley-Liss, Inc.