Summary of MedSun Reports Describing Adverse Events With Cardiac RF Ablation Catheters
MedSun: Newsletter #37, June 2009

A cardiac ablation catheter is a long, thin tube that is threaded into or onto the heart to destroy (ablate) an area of heart tissue that is causing abnormal heart rhythms. Cardiac ablation catheters are used to treat abnormally rapid heartbeats that cannot be controlled with medication, or in patients that cannot tolerate these medications. They are used most often to treat abnormal rhythms that begin in the upper heart chambers (atria). Some examples are Supraventricular tachycardia (SVT), Atrial Tachycardia, and Atrial Flutter. Less often, ablation can be used to treat heart rhythm disorders of the lower heart chambers (ventricles). [1]
Over the past 2 years, MedSun has received 27 adverse event reports associated with the Cardiac RF Ablation Catheter. The reports represent 3 manufacturers: 19 reports for Biosense Webster, 7 reports for Boston Scientific, and 1 report for St. Jude Medical. The reports were submitted by 7 hospitals between April 21, 2007 and April 21, 2009. The reported device problems were:

• Failure to deflect/straighten/directional control (6)
• Carto display error/failure to recognize catheter (5)
• Electrical interference (noise) on EKG channel (4)
• Inability to remove catheter/broken fragments remain in patient (3)
• Unexpected bend or curve in catheter (2)
• Temperature function/reading failures (2)
• Stopped working (2)
• Connection problems (1)
• Perforation (1)
• Failure to flush (1)

There were no MedSun reports that involved a patient death. The majority of reports did not involve any patient injuries. Patient problems were reported in 4 of these 27 reports.
• Break in the catheter/tip requiring surgical intervention to remove (3)
• Pericardiocentesis (1)

Of the reports that listed patient age, all had a patient age listed as greater than 21 years. A total of 8 reports involved female patients and a total of 16 reports involved male patients.

These MedSun reports contributed to FDA awareness of the device problems. The following recall, describing problems with deflection are noted to be associated with the Biosense Webster Lasso Catheter.

Recall Number: Z-1703-2008 and Z-1704-2008. See FDA weekly enforcement report for more details about the recall.

This recall was initiated on March 25, 2008 by Biosense Webster for the Lasso 2515 Variable Circular Mapping Catheter, US Catalog Number D7L202515RT.

This recall was initiated after the firm received several complaints reporting issues with deflection. The catheter may become caught in the mitral valve, requiring surgical procedures, valve may be torn while trying to dislodge, unable to retract the catheter through the sheath and require surgical intervention to remove, pulling on catheter to remove may lead to large atrial septal tear, and separation of the distal end of the catheter may occur. Also, the firm determined that when the catheter is fully deflected and the variable loop is fully contracted, it is possible that the catheter mechanism can become "locked" in position and cannot return to the un-contracted, un-deflected state. This could lead to damage to the device or limit the ability to withdraw the catheter safely.

Please note a New Device Approval: NaviStar ThermoCool and EZ Steer ThermoCool Nav Irrigated Deflectable Diagnostic/Ablation Catheter for Treatment of Paroxysmal Atrial Fibrillation
Approval Date: February 6, 2009.

[Note: The reports have been edited for clarity]


Cardiac RF Ablation Catheters
Device Device Identifiers Event Description
Biosense Webster/EZ Steer Nav Bi-directional Catalog # BN7TDD4L; Lot # 13206693AThe temperature function on the Stockert generator failed. The case was delayed while switching out to other generator/catheter. There was no harm to the patient. Biomedical assessment: The problem was the catheter temperature function failed during case. Corrective action/recommendations: Confirmed problem. Sent device to Biosense Webster for evaluation/repair.
Biosense Webster/Lasso No Device Identifiers During ablation procedure the tip of the catheter broke off in the left ventricle. The physician was unable to remove and took the patient to surgery for retrieval (emergency sternotomy). The device tips and catheter will be sent to the company for review. .
Biosense Webster/NaviStar DS No Device IdentifiersWhile undergoing a left atrial ablation for supraventricular tachycardia via a trans-septal approach, the patient sustained perforation of the left atrium. Immediate care was given that included pericardiocentesis, intubation and appropriate drugs. The patient is still an inpatient, but doing well. No surgery was required.
Biosense Webster/NaviStar RMT DSCatalog # NR7TCS8YU; Lot # 13280885 Catheter image did not display onto to the Carto system, preventing the procedure from continuing. All connections were checked and a brand new handle was connected to the catheter. This did not resolve the issue. The catheter was replaced with a brand new duplicate catheter. This resolved the issue. No patient harm was involved due to this issue.
Biosense Webster/NaviStar ThermoCool Catalog # N175TCFH; Lot # 13276491The ECG signal displayed inappropriate noise. All connections were checked and the catheter handle replaced with another handle. This did not resolve the issue. Finally the catheter was then exchanged for another brand-new catheter and this resolved the issue.
Biosense Webster/NaviStar ThermoCool Catalog # N175TCFHThe Carto was not recognizing the catheter. Replaced with a new catheter and problem was solved.
Biosense Webster/NaviStar ThermoCool Catalog # N175TCDH; Lot # 13451381The patient was to receive an RF ablation for atrial fibrillation. The right superior pulmonary vein was accessed without difficulty or resistance. However, the ablation catheter could not be withdrawn beyond the os of the vein. Despite manipulation of the catheter with and without the aid of the trans-septal sheath, the tip of the catheter was affixed to the pulmonary vein. Using intra-cardiac echo and fluoroscopy, the position of the catheter was verified to be in the pulmonary vein. There was no evidence of pericardial effusion at that time. Despite at least moderate traction, the tip could not be freed. The patient ultimately had to be transferred to surgery so that a sternotomy could be performed. The ablation catheter was then able to be removed and a full left atrial maze procedure was done. The post-op course was uneventful and the patient was discharged home on post-op day 3.
Biosense Webster/NaviStar ThermoCool Catalog # N175TCFHThere was no connection with the catheter and the power interface (PI) unit. The handle was changed and then the catheter was changed which finally resolved the problem. No harm came to the patient.
Biosense Webster/NaviStar ThermoCool Catalog # N175TCDH; Lot # 14018966The catheter would not properly deflect.
Biosense Webster/NaviStar ThermoCool Catalog # N175TCFH; Lot # 14027989The catheter would not properly deflect.
Biosense Webster/NaviStar ThermoCool Catalog # N175TCFH; Lot # 14041759The catheter would not straighten. No harm came to the patient.
Biosense Webster/NaviStar ThermoCool Catalog # N175TCFH; Lot # 14025914 The catheter would not flush properly. No harm came to the patient.
Biosense Webster/NaviStar ThermoCool Catalog # N175TCFH; Lot # 14034362The catheter would not deflect. No harm came to patient.
Biosense Webster/NaviStar ThermoCool Catalog # NI75TCFH; Lot # 13354189The catheter displayed noise on the electrocardiogram channel. No warning icon was displayed via NaviStar Carto system. The staff exchanged catheter handle and there was no improvement. The staff exchanged connecting wires of Carto system and again no improvement. Last, staff exchanged the catheter for another brand new catheter and this resolved the issue. There was no harm caused to the patient through this entire issue.
Biosense Webster/NaviStar ThermoCool Catalog # NI75TCFH; Lot # 13383420The error message 202M appeared on the Carto system. All connections were checked. Finally, the catheter was exchanged for a duplicate catheter and this resolved the issue.
Biosense Webster/NaviStar ThermoCool Catalog # NI75TCFH; Lot # 13391891The temperature readings for the ablation catheter were too high. The catheter handle was exchanged for a duplicate handle and this did not resolve the issue. Then the catheter was exchanged for a duplicate catheter and this resolved the issue. There was not any patient harm involved due to this incident.
Biosense Webster/NaviStar ThermoCool Catalog # NI75TCFH; Lot # 13375742 An error message appeared on the Carto system stating, "check mapping catheter connection." This prevented the procedure from continuing. A new catheter handle was used and did not fix the problem. The catheter was replaced with a duplicate, brand-new catheter. This fixed the problem. There was not any patient harm involved due to this issue.
Biosense Webster/NaviStar ThermoCool Catalog # NI75TCFH; Lot # 13276491Electrocardiogram signal on the NaviStar ThermoCool irrigated tip ablation catheter displayed inappropriate noise. All connections were checked and the catheter handle was replaced with another handle. This did not resolve the issue, and finally the catheter was then exchanged for a new catheter, which resolved the issue.
Biosense Webster/QwikStar Catalog # QS7TCF4M; Lot # 13266194After correctly connecting the catheter and catheter handle to the Carto system, the intra-cardiac ECG did not display. All connections were checked. The catheter was then exchanged for another brand-new catheter and this corrected the issue.
Boston Scientific/Blazer II Model # M0045031TL; Lot # 11395455No patient was identified. The catheter torque ability became defective during the procedure. Catheter was exchanged for another catheter. There was no harm caused to the patient from this incident.
Boston Scientific/Blazer II Model # M0045031TK20; Lot # 9506623The doctor was using the device when it was noticed that it had an improper curve. The device was removed from use and replaced with a new catheter.
Boston Scientific/Blazer II Model # 5031TL; Lot # 9435914When the catheter was taken from the packaging, it was found to be bent at the distal end. A new catheter was opened to proceed.
Boston Scientific/Blazer II Model # M0045031TL; Lot # 12034733Non-correctable electrical interference noted from catheter. There was a lot of noise on intracardiac channel. No harm came to the patient.
Boston Scientific/Blazer II Model # 5031T; Lot # 10575002The doctor reports that the ablation catheter was used for 19 ablations when the catheter stopped working. The catheter was removed and replaced with a new device. The patient was not harmed.
Boston Scientific/Chilli II Model # M00490310; Lot # 9777695The patient was undergoing an ablation for atrial flutter. The physician placed an 8 FR sheath in the right groin for ablation purposes. The sheath was easily placed and the ablation catheter was inserted without difficulty. However, when the physician tried to remove the sheath, the ablation catheter became "stuck." The physician was unable to turn the sheath. No extra force was applied. Eventually, the catheter was able to be removed. The physician used another catheter to complete the procedure. There was no patient harm in this event. The manufacturer rep came to the risk management department a few days after the event to see the device, and will have the manufacturer send a mailing label to return the device for evaluation. Per the manufacturer rep, they have experienced this kind of problem before, and are recommending that physicians use a larger size sheath. The physicians were notified and have already changed their practice to increase sheath size from an 8 FR to an 8.5 FR. To date, no other problems with the device have been reported by either the physicians or the cath lab staff.
Boston Scientific/Chilli II Model # M00490310; Lot # 9788662The physician inserted the cooled ablation catheter and was getting it into position. Once there, the physician was unable to get the directional control to work and said it appeared that the catheter was in a "fixed mode." The physician was unable to get the directional control to work and had to remove the catheter. Another catheter from the same company was used--same size--and worked as expected. There were no visual defects seen on the device that did not work. There was no patient harm.
St. Jude Medical/Livewire Model # 402149Patient undergoing cardiac cath and electrophysiology studies of the heart (to check conductivity) were done due to the patient's atrial fibrillation. An ablation catheter was utilized. As the catheter was being advanced towards the tricuspid valve, the catheter broke and ensnared in the tricuspid valve. The catheter could not be removed. Patient was taken to the operating room, chest was opened and patient was placed on bypass so that wire could be removed from tricuspid valve.



Additional Information:

Recall Number: Z-1703-2008 and Z-1704-2008. See FDA weekly enforcement report for more details about the recall, online available:
http://www.fda.gov/Safety/Recalls/EnforcementReports/ucm161725.htm

New Device Approval: NaviStar ThermoCool and EZ Steer ThermoCool Nav Irrigated Deflectable Diagnostic/Ablation Catheter for Treatment of Paroxysmal Atrial Fibrillation February 6, 2009.
http://www.fda.gov/MedicalDevices/ProductsandMedicalProcedures/DeviceApprovalsandClearances/Recently-ApprovedDevices/ucm125525.htm


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