Coronary guide wires are the unsung heroes of interventional cardiology. Though small — typically 0.014 inches (0.36mm) in diameter — they are the critical first step in every percutaneous coronary intervention (PCI), peripheral angioplasty and chronic total occlusion (CTO) crossing procedure. Selecting the right guide wire is as important as choosing the right stent or balloon catheter.
This article compares the three leading guide wire systems available from India's Backbone Pharma: Asahi Intecc (Japan), Terumo (Japan) and Merit Medical (USA) — covering their design philosophies, product ranges, performance characteristics and ideal clinical applications.
India's Backbone Pharma is an authorised distributor of Asahi Intecc, Terumo and Merit Medical guide wires in India and 50+ export markets. All products carry CE, FDA and ISO 13485 certifications with full batch traceability.
Guide Wire Anatomy: Understanding What Matters
Before comparing brands, it's important to understand the key parameters that define guide wire performance:
- Tip load (tip stiffness): Measured in grams. Lower tip loads (0.5–1.5g) for soft, tortuous vessels; higher loads (3–12g+) for CTO crossing
- Coating: Hydrophilic (slippery, good for tortuous anatomy), PTFE/hydrophobic (better torque, tactile feedback), or combination
- Torquability: 1:1 torque transmission allows precise tip control through tortuous vessels
- Flexibility: Distal flexibility prevents coronary spasm and perforation in delicate anatomy
- Tip shape: Pre-shaped (J-tip, angled) or user-shapeable
- Length: Standard 175–190cm; exchange length 300cm for balloon/stent exchange
Asahi Intecc Guide Wires — The Gold Standard for CTO
Asahi Intecc Corporation (Japan) is widely regarded as the world leader in coronary guide wire technology, particularly for complex PCI and chronic total occlusion procedures. Their wires feature ultra-high-quality stainless steel or nitinol cores with proprietary Durasteel core wire technology.
Asahi Runthrough NS — The Workhorse Wire
The Runthrough NS (Non-Supportive) is Asahi's flagship workhorse coronary guide wire for routine PCI. It features a hydrophilic coating and a spring coil tip with a 0.5g tip load — offering excellent flexibility and trackability in tortuous coronary anatomy. This is the first wire most operators reach for in routine PCI.
- Tip load: 0.5g | Core: Stainless steel with tapered distal core
- Coating: Hydrophilic distal 27cm, PTFE proximal
- Ideal for: Routine PCI, non-occlusive lesions, tortuous coronaries
Asahi Sion and Sion Blue — Complex Anatomy Specialist
The Sion series features Asahi's proprietary coil structure designed for complex, tortuous anatomy. The Sion Blue has a slippery hydrophilic coating for particularly tortuous vessels. Both deliver excellent 1:1 torque response.
- Tip load: 0.5g | Ideal for: Tortuous anatomy, bifurcation lesions
- Sion Blue: Extra-slippery for extreme tortuosity
Asahi Fielder FC — The CTO Soft Wire
The Fielder FC is designed for the initial CTO crossing attempt using the parallel wire or gentle probing technique. Its hydrophilic soft tip allows navigation into tight CTO caps.
- Tip load: 0.8g | Coating: Full hydrophilic
- Ideal for: Soft CTO, short occlusions, initial CTO probing
Asahi Conquest Pro — Hard CTO Specialist
For calcified, hard CTO cases, the Conquest Pro offers a stiff tapered tip (9g or 12g) with excellent penetration force while maintaining safety through its microtapered design.
- Tip load: 9g / 12g variants
- Ideal for: Hard, calcified CTOs, resistant fibrous caps
Terumo Radifocus Guidewire M — The Peripheral Specialist
Terumo's Radifocus Guidewire M is a hydrophilic-coated guide wire designed for peripheral vascular interventions and diagnostic catheterisation. Its Hydra-coat coating provides exceptional lubricity for smooth navigation through complex peripheral anatomy, tortuous iliofemoral vessels and subclavian approaches.
Radifocus Standard Type
- Diameter: 0.035″ (standard) and 0.018″ (peripheral intervention)
- Coating: Full-length hydrophilic Hydra-coat
- Tip shapes: Straight, angled (45°), J-tip
- Ideal for: Peripheral angiography, diagnostic catheters, femoral/radial access
Radifocus M for Coronary Use (0.014″)
- Tip load: 1.0g | Full hydrophilic coating
- Ideal for: Coronary angiography, routine PCI with tortuous access routes
Merit Medical Laureate — The Value-Performance Option
Merit Medical's Laureate hydrophilic guide wire offers excellent performance at a competitive price point, making it popular in high-volume PCI centres and government hospital procurement. The Laureate features a hydrophilic polymer coating over its distal section and a PTFE-coated proximal section for tactile feedback.
- Tip load: 0.8g (standard) | 1.5g (intermediate) | 3.0g (stiff)
- Diameter: 0.014″ and 0.018″ versions
- Coating: Hydrophilic distal 20cm, PTFE proximal
- Tip shapes: Straight, angled | Length: 175cm and 300cm (exchange)
- Ideal for: Routine PCI, high-volume labs, budget-conscious procurement
Comparison Summary
| Feature | Asahi Intecc | Terumo | Merit Medical |
|---|---|---|---|
| CTO Capability | ★★★★★ | ★★☆☆☆ | ★★☆☆☆ |
| Routine PCI | Excellent | Excellent | Good |
| Peripheral Use | Limited | Excellent | Good |
| Value for Money | Premium | Mid-range | Best |
Procurement Recommendations
- High-volume PCI lab: Stock Asahi Runthrough NS as the workhorse + Asahi Sion for complex cases + Merit Medical Laureate for cost-sensitive routine cases
- Dedicated CTO programme: Build an Asahi-based CTO wire library — Fielder FC, Sion, Gaia series, Conquest Pro
- Peripheral vascular lab: Terumo Radifocus 0.035″ and 0.018″ as primary wires
- Government / high-volume tender: Merit Medical Laureate for core stock; Asahi for complex cases
India's Backbone Pharma maintains ready stock of all three brands with 0.014″, 0.018″ and 0.035″ sizes available. Emergency same-day dispatch available for cardiac centres in North India. Contact us for bulk pricing and regulatory documentation.