The Boston Scientific RELIANCE 4-FRONT DF4 ICD Defibrillation Lead (REF 657) is a transvenous defibrillation lead designed for chronic implantation in the right ventricle as part of a compatible implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) system. The lead utilizes the standardized DF4 connector format to consolidate the high-voltage and pace/sense terminals into a single in-line connector pin, simplifying device pocket management and reducing connection complexity at the header.

Key Features
Single in-line DF4-LLHH connector compatible with DF4-compliant Boston Scientific pulse generators
Dual-coil high-voltage configuration for ventricular defibrillation therapy
Active fixation distal tip designed to support stable right ventricular placement
Steroid-eluting collar intended to mitigate acute pacing threshold rise
RELIANCE 4-FRONT lead family construction engineered for chronic transvenous use
Sterile, single-use device supplied with stylets and accessories per manufacturer packaging

Clinical Applications
Right ventricular sensing, pacing, cardioversion and defibrillation when connected to a compatible ICD or CRT-D pulse generator
Transvenous implantation for management of patients indicated for ICD therapy per the implanting physician and applicable device labeling
Use as the high-voltage ventricular lead within Boston Scientific DF4-based defibrillator systems

Product Information
Brand: Boston Scientific
Product Family: RELIANCE 4-FRONT
REF / UPN: 657
Category: ICD Leads for Implantable Cardioverter Defibrillators
Connector: DF4 (in-line)
Configuration: Dual-coil defibrillation lead
Fixation: Active
Lead Length: Not specified in the located sources
Sterility: Sterile, single-use
Compatibility: Boston Scientific DF4-compatible ICD/CRT-D pulse generators (refer to manufacturer compatibility matrix)
Regulatory status, indications, contraindications and full specifications: Refer to the official Boston Scientific Instructions for Use.