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THREADER™ Micro-Dilatation Catheter

Indications, Safety, and Warnings

Threader Micro-Dilatation Catheter

CAUTION: Federal law (USA) restricts this device to sale by or on the order of a physician. Rx only. Prior to use, please see the complete “Directions for Use” for more information on Indications, Contraindications, Warnings, Precautions, Adverse Events, and Operator’s Instructions.


The Threader Micro-Dilatation Catheters are indicated for pre-dilatation of the stenotic portion of a coronary artery or bypass graft stenosis (≥70% stenosis) for the purpose of improving myocardial perfusion. The Threader Micro-Dilatation Catheters are intended to provide support to facilitate the placement of guidewires in the coronary vasculature. The Threader Over-The-Wire Micro-Dilatation Catheter can also be used to exchange one guidewire for another. The Threader Over-The-Wire Micro-Dilatation Catheter is also intended to allow hand-injection of contrast media into the coronary vasculature.


The Threader Micro-Dilatation Catheter is contraindicated for use in:

  • Unprotected left main coronary artery disease.
  • Coronary artery spasm in the absence of a significant stenosis.


PTCA in patients who are not acceptable candidates for coronary artery bypass graft surgery requires careful consideration, including possible hemodynamic support during PTCA as treatment of this patient population carries special risk. Use extreme caution and careful judgment in patients for whom anticoagulation is contraindicated. Use extreme caution and careful judgment in patients who have reaction to contrast agents that cannot be adequately pre-medicated. PTCA should only be performed at hospitals where emergency coronary artery bypass graft surgery can be performed. To reduce the potential for vessel damage, the inflated diameter of the balloon should approximate, or be less than, the diameter of the vessel just proximal and distal to the stenosis. Use only the recommended balloon inflation medium. Never use air or any gaseous medium to inflate the balloon. When the balloon catheter is exposed to the vascular system, it should be manipulated while under high-quality fluoroscopic observation. Do not advance or retract the catheter unless the balloon is fully deflated. If resistance is felt during manipulation, determine the cause of the resistance before proceeding. Do not exceed the balloon rated burst pressure. The rated burst pressure is based on the results of in vitro testing. At least 99.9 percent of the balloons (with a 95 percent confidence) will not burst at or below their rated burst pressure. Use of a pressure monitoring device is recommended to prevent over or under pressurization. If difficulty is experienced during balloon inflation, do not continue; remove the catheter. Before withdrawing the balloon catheter, visually confirm complete balloon deflation by fluoroscopy. Balloon catheter retrieval methods (use of additional wires, snares and/or forceps) may result in additional trauma to the treated vessel and/or the vascular access site. Complications can include but are not limited to bleeding, hematoma, pseudoaneurysm or dissection. The safety and effectiveness of the Threader Micro-Dilatation Catheter have not been established for the treatment of chronic total occlusions. The risk of adverse events is likely to be higher when treating such lesions. Physicians should be aware of this increased risk and the limitations of the available scientific evidence.


The compatibility of the device has not been evaluated for the delivery of materials (e.g., alcohol or nitroglycerine, stem cells, etc.) through the guidewire lumen, other than those required for normal use. The balloon catheter should be used only by physicians trained in the performance of percutaneous transluminal coronary angioplasty. The safety and effectiveness of this PTCA balloon catheter for the treatment of in-stent restenosis (ISR) has not been established. This balloon is not intended for the expansion or delivery of a stent. Prior to angioplasty, the balloon catheter should be examined to verify functionality and to ensure that its size and shape are suitable for the specific procedure for which it is to be used. Caution should be taken not to overtighten a hemostatic adapter around the catheter shaft as lumen constriction may occur, possibly affecting inflation/deflation of the balloon. Before insertion of the balloon catheter, administer appropriate anticoagulant and coronary vasodilator therapy. Care should be taken to control the position of the guide catheter tip during manipulation of the balloon catheter. When loading or exchanging the balloon catheter, it is recommended to thoroughly wipe the guidewire clean for better catheter movement on the guidewire. Do not expand the balloon if it is not properly positioned in the vessel. In the case of simultaneous use of two Threader™ balloon catheters in one guide catheter, care should be taken when introducing, rotating, and removing guidewires and balloon catheters to avoid entanglement.


Potential adverse events (in alphabetical order) that may be associated with the use of a Micro-Dilatation Catheter include, but are not limited to, the following:

  • abrupt closure
  • acute myocardial infarction
  • angina or unstable angina
  • arrhythmia, including ventricular fibrillation
  • arteriovenous fistula
  • cardiac tamponade/pericardial effusion
  • cardiogenic shock
  • cerebrovascular accident/stroke
  • coronary aneurysm
  • coronary artery bypass graft surgery
  • coronary artery spasm
  • coronary vessel dissection, perforation, rupture or injury, possibly requiring surgical repair or intervention
  • death
  • drug reactions, including allergic reaction to contrast medium
  • embolism
  • hemodynamic compromise
  • hemorrhage or hematoma
  • hypo/hypertension
  • infection
  • minor vessel spasm
  • myocardial ischemia
  • pseudoaneurysm (at vascular access site)
  • pyrogenic reaction
  • renal failure
  • respiratory insufficiency
  • restenosis of the dilated vessel
  • side branch occlusion
  • slow flow/no reflow
  • target vessel re-intervention
  • thrombosis
  • total occlusion of the coronary artery or bypass graft
  • transient ischemic attack
  • vasovagal reaction
  • volume overload