Summary of MedSun Reports Describing Problem With Coronary Stents
MedSun: Newsletter #63, August 2011

Coronary stents are small metal or wire mesh tubes used to prop open a stenotic or narrowed coronary artery, or saphenous vein. Stents are inserted using a specialized balloon catheter during angioplasty or percutaneous coronary intervention (PCI). Stents may be coated with medication released over time after implantation. (Food and Drug Administration Product Code Classification, 2011).

Over the past 2 years, MedSun has received 23 adverse event reports associated with this device type manufactured by Abbott Vascular, Boston Scientific Corporation, and Medtronic Vascular. The reports were submitted by 19 hospitals between January 2009 and May 2011.

The reported device problems were:
•Failure to deploy (3)
•Failure to advance (3)
•Positioning Issue (3)
•Component missing (1)
•Material separation (1)
•Difficult to remove (1)
•Detachment of device component (1)
•Premature deployment (1)
•Inadequate instructions for healthcare professional (1)
•Out-of-box failure (1)
•Material rupture (1)
•Break (1)
•Uncoiled (1)
•Dislodged or dislocated (1)
•Entrapment of device or device component (1)
•Occlusion within device (1)
•No information (1)

Of the 23 reports, the most frequently reported patient problems listed below were:
•Device fragment/foreign body in patient (6)
•Chest pain/cardiac arrest (4)*
•Dissection/impaired vasculature (2)
•Device explanation required (2)
•Embolus (1)

*Two post procedural deaths were reported after symptom of chest pain and cardiac arrest. There were no patients under the age of 21 years. Of the 23 reports listed, 4 involved female patients and 19 involved male patients.

These MedSun reports summarized above, in addition to manufacturer, healthcare, and voluntary reports contributed to FDA awareness of the device problems.

The following recalls are associated with coronary stents since 2009. The MedSun reported events may, or may not, be involved in the recall(s) listed.

Recall Number: Z-0068-2010 (Class II)
Date Posted: 10/21/2009
Product: Liberte©® Bare-Metal stent
Code Information: Material Batch H7493893412270 9049696 H7493893412270 9057624 H7493893412270 9099450 H7493893412270 9139074 H7493893412270 9160483 (truncated)
Recalling firm/Manufacturer: Boston Scientific Corporation
Action: Boston Scientific initiated a field correction for the Liberté® Bare-Metal coronary stent products. They have received reports from cardiac cath labs that TAXUS Liberte Paclitaxel-Eluting (TAXUS® Liberté® Drug-Eluting) coronary stents have been inadvertently selected when the interventional cardiologist intended to implant a Liberté® Bare-Metal stent, and Liberté® Bare-Metal stents have been inadvertently selected when the interventional cardiologist intended to implant a TAXUS® Liberté® Drug-Eluting stent. Selecting the wrong device may present a risk of serious injury, including death. Because of the importance of accurate device selection to patient safety, Boston Scientific is renaming the Liberté® Bare-Metal stent. The new name is VeriFlex" Bare-Metal. Representatives from Boston Scientific will be visiting all impacted health care facilities to re-label the outer boxes of all existing Liberte® Bare-Metal stents held in inventory, to reflect the new name.
Distribution: Nationwide, including Puerto Rico ( 391,769 devices)
Information Online: http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfRES/res.cfm?id=85496


Recall Number: Z-1367-2011
Date Posted: August 21, 2009
Product: Endeavor Resolute Zotarolimus-Eluting Coronary Sten System with Rapid Exchange Delivery System
Code Information: Lot Numbers: V00265135, V00265136, V00265137, V00265139, V00265140, V00265141, V00265142, V00265143, V00265144, V00265145, V00265146, V00265147, V00265148, V00265149, V00265150, V00265151, V00265152, V00265153, V00265154, V00265155, V00265156, V00265157, V00265158, V00265159, V00265160, V00265161, V00265169, V00265170, V00265171, V00265177, V00265178, V00265179, V00265180, V00265181, V00265182, V00265183, V00265188, V00265189, V00265190, V00265191, V00265194, V00265195, V00265196, V00265223, V00265224, V00265232, V00265244, V00265251, V00265254
Recalling Firm: Medtronic Vascular Galway Limited
Action: The firm, Medtronic, sent their initial "Urgent Medical Device Recall Notice" to customers with affected product via e-mail on August 7, 2009. An additional "Urgent Medical Device Recall Notice" was sent to all customers on August 12-13, 2009 via FedEX and UPS. The notice described the product, problem and action to be taken by the customers. The customers were instructed to remove the affected units from their inventory and isolate the units in a secure location to prevent additional use. A Medtronic CardioVascular Clinical Customer Service (CCS) representative will contact their site to arrange for return of the units. This will be followed by a shipment of replacement units to their sites.
Distribution: Nationwide
Information online: http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfRES/res.cfm?id=84457


The following table lists the MedSun reports that are described in the device problem summary above.
[Note: The reports have been edited for clarity]

MedSun Reports Describing Problems with Coronary Stents
Device Manufacturer and BrandDevice Identifiers (Catalog Number, Model Number, Lot Number) Event Description
Abbott Vascular Inc., Multi-Link Mini Vision OTW NA, 1010152-12, 7013031 The cardiac stent improperly deployed during the procedure and was lost in vasculature. It was located next day.
Abbott Vascular Inc., Multi-Link Vision Rx NA, 1007849-23, 8041731 The stent catheter entered body without a stent on the balloon to deploy. A 0.014/190 cm filter wire was advanced through the guiding catheter into the distal portion of the vein graft. A 3.5/15 mm balloon dilatation catheter was then advanced over the guide wire and positioned in the mid vessel. Two inflations were performed at a maximum of 10 atmospheres. The balloon was removed and replaced with a 4.0/23 mm vision stent. This was deployed in the mid vessel at a maximum of 10 atmospheres. The stent delivery balloon was removed and repeat angiography showed the stent was patent but there was haziness in the proximal lesion. Therefore, a 3.5/23 mm vision stent was advanced over the guide wire and the balloon was inflated but there was no stent on the balloon. The balloon inflated to 10 atmospheres. The balloon was removed and replaced with a 3.5/23 mm vision stent. This was positioned in the lesion and deployed at 10 atmospheres. The stent delivery balloon was then removed. Repeat angiography showed sluggish flow in the vessel. The filter wire was then retrieved and the catheter was removed from body and kept.
Abbott Vascular Inc., Vision 2.0-12 VISION, NA, 9012641 The MD was placing the stent in right coronary artery(rca) when the stent separated from the delivery system and remained in RCA. The stent was subsequently crushed to side of the vessel and remains in patient’s RCA.
Abbott Vascular Inc., Jostent Covered Stent 3.5 MM/16 MM, NA, NA The patient underwent several passes w/ 1.5mm arthrectomy device at low speed. It was removed with guidewire entrapped. A new guidewire was inserted with difficulty. A balloon was deployed due to bleed. A jostent covered sent 3.0mm/ 16mm was deployed, then a second one was deployed, but would not cross first one. A balloon was inserted to allow for passage of the stent. The balloon caused the jostent stent to be stripped from the deployment device. The stent wedged into the proximal posterior tibial artery undeployed. Attempts to snare the stent were unsuccessful. A stent from another manufacturer was deployed and crushed jostent stent.
Medtronic Vascular, Endeavor Rx 3.5X18MM, NA, 900803 During coronary percutaneous coronary intervention (pci) a 3.5x18 drug eluting stent (DES) easily crossed lesion. However, during deployment, the balloon would not hold pressure. The balloon was withdrawn easily but the stent came off the balloon and lodged in the proximal circumflex artery near the left main. The patient was stable and sent to the OR for coronary artery bypass graft (CABG).
Boston Scientific Corporation, Liberte NA, NA, 12525756 The plan was to deploy the stent without pre-dilatation. The entire unit was removed from the coil protector and when the dilator was pulled off, the revap tool and the stent itself also came off. The decision was made by the interventionalist to proceed to use the balloon for pre-dilatation then asked for another stent which worked fine.
Boston Scientific Corporation, Liberte Bare Metal Stent NA, NA, NA The patient had a cardiac catheterization with stent placement. The physician requested a Liberte bare metal stent and was given a Taxus Liberte (drug eluting) stent. The Taxus Liberte was deployed and documented by nursing in the patient's medical record. The patient was given a wallet card bearing this information. The physician documented in the medical record that he inserted a bare metal stent. Several months later in the process of clearing the patient for knee surgery, the patient's primary care provider wanted/needed to discontinue the antiplatelets and discovered a discrepancy between the stent he thought had been inserted vs. the information provided to him by the doctor who performed catheterization/stent placement. There was no harm to the patient. However, it was thought that the surgery might be delayed due to the need to continue aspirin and Plavix therapy. The physician who placed the stent stated that packaging for both stents were identical: Same box, same labeling. He does not see the box, and is only handed the equipment.
Boston Scientific Corporation, Liberte NA, NA, 11499022 The patient had a 2.75 x 12 liberte stent placed in the circumflex artery. The patient returned to the cath lab approximately one month later for another scheduled procedure. The physician was using a prime wire in the left anterior descending (LAD) artery when he began to have difficulty advancing and removing the wire. Eventually he was able to remove the wire. When the wire was removed, it appeared to have the stent from the first procedure attached to it. It appeared that somehow the wire moved through one of the struts of the stent and got caught.
Medtronic Vascular, Microdriver Rx DRV25018UX, DRV25018UX, NA Patient with angina had angioplasty of a 90% obtuse marginal lesion. Attempts to maneuver two different stents to this area were unsuccessful. The patient developed chest pain approximately two weeks post-discharge and returned to the hospital. The cath films were reviewed and it was suspected that an undeployed stent was in the distal left main. The patient ultimately had triple bypass surgery after the initial heart cath (after return to the hospital) and the stent was removed.
Abbott Vascular Inc., Jostent Graftmaster NA, 106208-00/005, 537011 A 3.0 x 12 mm Jostent Graftmaster device was placed after left anterior descending (LAD) perforation during a cardiac cath procedure. This device initially seemed to adequately seal the perforation. However, the following day, the patient did suffer a cardiac arrest and expired. No autopsy done
Abbott Vascular Devices, Jostent Graftmaster GCG1630UA 3.0 X 16, NA, 580341 The physician was attempting to place a stent but the graft stent would not cross into the left anterior descending artery (lad). When the physician pulled it back out, the graft came off the balloon. The graft was stuck in the lad and was snared out. It would not pull out of the sheath, so the graft was stuck in the right profunda. It was felt that "due to wire bias against the vessel wall, it became trapped." The cath lab has contacted the manufacturer.
Abbott Vascular-Cardiac Therapies, Multi-Link Mini Vision Coronary Stent System 1007821-12, NA, 8022731 The physician was attempting to deploy a 2 x 12 mm stent in the left anterior descending artery. The physician had difficulty in advancing the stent past the mid vessel. The stent appeared to be catching on a previously deployed stent. The physician attempted to retrieve the stent but the stent would not come out. The physician was able to manipulate the stent until it came out, but the stent had dislodged from the balloon. The physician then introduced another stent into the left anterior descending artery. A 2 x 15 mm balloon was used to push the stent to the wall followed by a 2.5 x 15 mm stent. The stent was fully deployed and the dislodged stent was opposed into the wall with the new stent. There was no other intervention required
Boston Scientific Corporation, Veriflex NA, NA, 13008712 During left heart catheterization, a balance middle weight (BMW) wire was passed down into the circumflex branch. Initially a stent would not pass and then we placed a balloon. After pre-dilating the lesion a stent still would not pass in the more proximal portion of the vessel near a bend. Subsequently a guideliner catheter was placed to attempt to deliver the stent distally. This was not successful. The stent did not pass through the guideliner but the balloon did and an angioplasty of the distal portion of the vessel was completed. There was evidence of a dissection after the equipment was removed. Subsequently, there was evidence of loss of a small obtuse marginal (OM) branch. At this point, the bypass team was called for. Initially a stent was placed distally. Subsequently after pre-dilation of the more proximal area, another stent was placed proximally. These were 4.5 stents and were not drug-eluting. Subsequently a 2.5 promus stent was placed in the more distal portion of the OM branch. This was after evidence of new disease was seen there. The patient received intermittent doses of intracoronary nitroglycerin. The patient had transient chest pain. It was felt secondary to the loss of a very small distal portion of the circumflex. Next, hemostasis was achieved after angiography of the right external carotid artery. The patient was chest pain free by the termination of the procedure.
Abbott Vascular-Cardiac Therapies, Multi Link Vision NA, 1007850-18, 8101641 The stent was prepped in the standard fashion. The MD and scrub tech verified that the stent was never touched prior to insertion into the patient's body. After the stent was in the vessel and across the lesion, the MD noted that the stent was distal on the balloon, such that the stent was not located appropriately to the markers, and was more distal on the balloon than it should have been. At this point, the MD decided that to deploy the stent, a section of the stent may not inflate. It was decided to remove the stent. This was done successfully. After the stent was out of the body, the stent was evaluated. It was checked to see if it was "loosely" fitted around the balloon, and it was x-rayed out to the body to check against the markers. It appeared to be positioned incorrectly on the delivery system, not as a result of its prep, or its insertion into the patient but possibly coming from the manufacturer that way. Fibers can be seen currently on the stent, but were placed there after the stent was removed from the patient. The stent was not touched prior to its use. Health professional's impression: MD was concerned that if he hadn't noticed the misaligned stent, that a section of the stent would have not been deployed. To then pass a balloon through an undeployed stent may have proven to be a challenge, and would have placed the patient at risk of an unsuccessful procedure.
Medtronic Vascular, Integrity Rx NA, NA, 4606263 Unsuccessful stent deployment occurred. No stent was found on the stent deployment device (SDS). The patient remained stable and the procedure continued. Another stent was placed. The first undeployed stent was left in the patient.
Boston Scientific Corporation, Veriflex NA, NA, 12942553 During the procedure a Veriflex bare metal stent 5.0x28mm was introduced and the balloon was inflated to as high as 22 atmospheres of pressure due to calcifications and the lesions not expanding properly. Post procedure, the patient complained of chest pain and vital signs began to decompensate resulting in a code being performed on the patient. The same balloon was inflated to the area in an attempt to tamponade. On removal of the balloon, it was noted that it had ruptured. Findings from the surgeon included: large vein graft to the obtuse marginal (OM) showed two 95% stenoses distally post percutaneous coronary intervention (PCI) with some difficulty due to heavy calcification and final stent deployment with a 5.0 x 28mm Veriflex inflated to high pressure due to the calcification that caused a perforation and code arrest leading to the death of the patient.
Abbott Vascular-Cardiac Therapies, Graftmaster NA, GCG1630UA, 645954 The physician attempted to deliver a Graftmaster Jostent to a left circumflex coronary artery aneurysm through the Xience stent placed in left main artery. Once in the distal left main artery, it was determined that the Jostent would most likely not reach the aneurysm site. The Jostent was withdrawn, at which time the stent dislodged in the mid segment of the left main artery. A 4mm microsnare Amplatz loose neck snare was utilized to retrieve the Jostent intact and without difficulty. The patient remained hemodynamically stable.
Abbott Vascular-Cardiac Therapies, Multi-Link Vision NA, 1007848-18, 22541 Following a stent placement to the circumflex artery, a second stent was attempted to be placed distal to the first stent. The second stent, while still on the delivery system, became lodged in the proximal portion of the initially placed stent. The physician attempted to remove the stent and delivery catheter, but was unsuccessful. Upon further manipulation, the end of the catheter, which contained the un-deployed stent, broke off of the catheter and remained in the vessel. The guidewire and remainder of the delivery system was removed. An unsuccessful attempt was made to remove the indwelling stent and catheter with a snare. The case was aborted and the patient was referred for surgical removal of the pieces.
Medtronic Vascular Inc, Integrity Rapid Exchange Coronary Stent System 240INT25026UX, M719010B001, 100005000000 A 2.5 x 26mm integrity stent was advanced into a tortuous calcified artery. The stent was not deployed, and was removed from the patient. When the stent was removed, it was noted that part of the stent had uncoiled and pulled away from the stent delivery system (SDS). All parts were still intact and nothing was left in the body.
Medtronic Vascular, Integrity Bare Metal Stent INT27526LIX, NA, 4689611 During placement of the stent in the right coronary artery (RCA), the stent was noted to be advancing ahead of the balloon. The stent was thought to have become dislodged from the balloon. A smaller balloon was placed in the patient and that balloon was inflated to trap the dislodged stent. Another stent was placed without complication.
Medtronic Vascular Inc, Luge NA, NA, 2152874 During an elective percutaneous coronary intervention (PCI), the physician noted that the Luge wire had fractured. The wire remained in the patient. The patient was transferred to another facility for higher level of care.
Abbott Vascular-Cardiac Therapies, Multi-Link Mini Vision Rx Coronary Stent System NA, 1007822-15, 0092741 Angiographic report: repeat angiography revealed what appeared to be a linear dissection in the diagonal branch. With a 3.0 x 15 mm balloon in the left anterior descending, a 2.25 x 15 mm Minivision stent was placed in the diagonal branch and deployed at 10 atmospheres with simultaneous inflation of the balloon in the left anterior descending. Kissing balloon angioplasty was performed using a 2.5 mm balloon in the diagonal and a 3.0 x 15 mm balloon in the left anterior descending to 8 atmospheres. Repeat angiography at this point revealed good stent expansion in both the left anterior descending and the diagonal. The guide wire was removed from the left anterior descending. Attempts to remove the guide wire from the diagonal resulted in the PT2 ms guide tip being entangled in the distal end of the diagonal stent and attempts to remove this were unsuccessful. Attempts to dislodge the wire tip using a 2.0 x 15 mm balloon and a 1.5 x 15 mm balloon were unsuccessful. A guideliner was also tried and attempts with the balloon to push the wire off the distal end of the stent were unsuccessful. With a 1.5 mm balloon in the diagonal branch to the tip of the guide wire, the wire was pulled resulting in lead tip fracture. The remaining guide wire and the 1.5 mm balloon were removed. Attempts to wire the left anterior descending using a wire were unsuccessful. A high-torque floppy wire was passed successfully due to the stent in the left anterior descending into the distal vessel. The left anterior descending was dilated using a 1.5 x 15 mm balloon to 8 atmospheres at 2.0 x 15 mm balloon to 14 atmospheres and a 3.0 mm balloon to 16 atmospheres. A 3.0 x 12 mm vision stent was then inserted, but would not pass. The proximal left anterior descending was again dilated using a 3.0 x 15 mm balloon to 12 atmospheres. A 3.0 x 12 mm vision bare metal stent was then placed proximally and deployed at 11 atmospheres post dilated using a 3.0 x 15 mm balloon to 18 atmospheres.
Boston Scientific Corp., Veriflex (Liberte)Bare Metal Coronary Stent System 38934-1635, NA, 14040504 Elderly male underwent a cardiac cath procedure. Following successful angioplasty of the posterior descending artery (PDA) & Veriflex bare-metal stent was deployed into the proximal right coronary artery (RCA) and was noted that one stent embolized in the distal portion of the RCA. The patient was brought back to cath lab suite. Selective angiography confirmed embolization of the undeployed stent at the distal portion of the RCA. Another bare-metal stent 3.5 x 12 was deployed across the proximal portion of the vessel. Post dilatation of both stents then performed with 3.25 x 8 non-compliant balloon. No residual stenosis. The used system was discarded prior to the identification of an issue.


Additional Information:

(2011). Product Classification. Retrieved from FDA Product Classification Website:
http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfPCD/classification.cfm


MedSun Newsletters are available at www.fda.gov/cdrh/medsun