Sensei robotic catheter system

The Sensei X robotic catheter is a medical robot designed to enhance a physician’s ability to perform complex operations using a small flexible tube called a catheter. As open surgical procedures that require large incisions have given way to minimally invasive surgeries in which the surgeon gains access to the target organs through small incisions using specialized surgical tools. One important tool used in many of these procedures is a catheter used to deliver many of things a surgeon needs to do his work, to impact target tissue and deliver a variety of medicines or disinfecting agents to treat disease or infection.

Manufactured by Hansen Medical, Sensei X is a specialized robotic catheter system that is controlled by a physician and is designed for accurate positioning, manipulation and stable control of catheter and catheter-based technologies during cardiovascular procedures. The Sensei system obtained U.S. Food and Drug Administration (FDA) clearance in 2007, after which the Cleveland Clinic's electrophysiology program, then directed by Dr. Andrea Natale, received the first placement. The Sensei Robotic Catheter System and Artisan Extend Control Catheter allow physicians to navigate flexible catheters with greater stability and control during complex cardiac arrhythmia procedures. Hansen Medical has related co-development agreements with the following industry leaders: St. Jude Medical, GE Healthcare, Siemens Healthcare, and Philips Medical Systems.

Hansen Medical was founded by Dr. Frederic Moll, who had also co-founded Intuitive Surgical, manufacturer of the Da Vinci Surgical System, whose use has propelled medicinal robotics to the forefront of patient care. The Sensei system is indicated for use during the cardiac mapping phase of cardiac arrhythmia treatment in the US. Meanwhile, it has CE mark approval for facilitating the navigation of ablation catheters within the atria of the heart during complex arrhythmia procedures such as Atrial Fibrillation (AF).

In November 2010, Hansen Medical received unconditional Investigational Device Exemption (IDE) approval from the FDA initiating a clinical trial to investigate the use of the Sensei X Robotic Catheter System and the Artisan Control Catheter for treatment of AF, the most common cardiac arrhythmia. The Principal Investigator of the ARTISAN AF Trial is Dr. Andrea Natale, executive medical director for Texas Cardiac Arrhythmia Institute (TCAI). The first case in the trial was completed by Dr. Joseph Gallinghouse, an electrophysiologist, at the TCAI at St. David's Medical Center.^[1]

By the end of 2010, nearly 100 Sensei systems have been shipped worldwide since its 2007 release. The system has been used to perform almost 5,000 procedures.^[2] The Sensei system operates by guiding standard catheters through a manipulated robotically steerable sheath (hollow tube) in the patient's vasculature. The doctor performs the procedure at a control station with a technology called "IntelliSense" to proximally measure the forces applied along the shaft of the catheter as a result of catheter tissue contact. The Artisan catheter has two robotically controlled segments which provides six degrees of freedom and 270 degrees of bend articulation which can assist physicians in accessing hard-to-reach cardiac anatomy. The open lumen Artisan catheter accommodates 8F percutaneous EP catheters. Centers have reported acute and long term success rates consistent with manual procedures.^[3][4][5][6]

The Sensei Robotic System in clinical use

Although the Sensei system was initially tested in a range of ablation procedures including SVT and typical atrial flutter,^[7][8] there is most excitement about its role in complex ablation procedures such as for atrial fibrillation (AF), where the ability to manipulate catheters to precise locations within the heart and keep them stable in the desired position is crucial. Achieving adequate tissue contact, ideally with a small amount of pressure being applied by the catheter during ablation, is also essential to effectively destroy the heart tissue responsible for arrhythmia. The ability to titrate catheter contact force using the Sensei system’s built-in pressure sensor technology (called intellisense) may allow operators to maximise the chance of creating effective burns across the thickness of the atrial wall, whilst minimising the risk of complication.^[9] Intracardiac echocardiography has also demonstrated that greater catheter stability is achieved with robotic compared to manual catheter delivery.^[10] Consequently, there is evidence that robotic ablation causes more effective and more efficient burns.^[11]

Use of robotic navigation for catheter ablation was also designed to allow Electrophysiology to perform most of the procedure without being exposed to X-rays (or radiation). The radiation dose to the operator during a conventional manual ablation procedure is relatively small, although there is cumulative exposure that becomes an important consideration for operators performing procedures on a daily basis. By performing procedures a few metres away using a robotic system and seated in the leaded anteroom, the operator is shielded from X-rays and is less vulnerable to operator fatigue, which may affect operator performance in long complex cases. Use of robotic navigation has been shown to reduce fluoroscopy times in catheter ablation of AF, resulting in reduced X-ray exposure for patients and other health care professionals present in the catheter laboratory.^[12][13][14]

Early Experience with the Sensei Robotic System

The system has been the subject of several clinical trials in the USA and Europe, particularly for the catheter ablation of AF. There were early safety concerns after the ‘first-in-human’ studies suggested high complication rates. Wazni et al. reported experience with the first 71 catheter ablations for AF in their centre using the Hansen robotic navigation system starting from 2005.^[15]

These early studies have allowed others to incorporate changes to their technique,^[16] and hence recent work has produced complication rates for catheter ablation of AF comparable to procedures performed manually.^[17][18][19] The field of robotic ablation is growing and evolving rapidly, and randomised controlled trials comparing robotic to manual ablation are ongoing in Europe and the USA to see if these potential advantages will translate into better clinical outcomes.

Recent studies using the Sensei Robotic system

Since there are no completed randomised controlled trials comparing robotic ablation to manual ablation, comparing the modalities remains difficult. Techniques, complication rates and clinical results vary widely between centres for both manual and robotic procedures, making registry data difficult to compare. Typical ranges for procedures performed manually are: major complication rates of 3-5%, and success rates of approximately 80-90% for paroxysmal AF and 70-75% for persistent AF (depending on the length of follow-up).^[20][21] The following are recent reports in medical journals detailing experience of the Sensei system in the catheter ablation of AF, and demonstrate approximate success and complication rates at the time of writing:

Study	Parameter	Robotic ablation	Manual ablation
Prague[22] 2011	Number of subjects	100 total All paroxysmal	(No comparator group)
Pulmonary vein isolation achieved acutely	100%
Procedure time	3.7 ± 0.9 hours
Fluoroscopy time	11.9 ± 7.8 minutes
Clinical success (Freedom from AF )	63% at 15 ± (3-28) month, 86% after 21 patients had a repeat procedure
Safety	Total complications 0%
Texas Group[23] 2009	Number of subjects	193 total 135 paroxysmal 55 persistent 6 long-lasting persistent	197 total (registry cohort) 127 paroxysmal 55 persistent 11 long-lasting persistent
Pulmonary vein isolation achieved acutely	100%	100%
Procedure time	3.1 ± 0.8 hours	3.1 ± 0.8 hours
Fluoroscopy time	48.9 ± 24.6 minutes	58.4 ± 20.4 minutes
Clinical success (Freedom from AF )	Overall 85% at 14 ± 1 month Paroxysmal AF 90% Persistent AF 71% Long-lasting 100% (of only 6)	Overall 81% at 14 ± 1 month Paroxysmal AF 85% Persistent AF 73% Long lasting 67%
Safety	Total complications 1.5% 1% tamponade	Total complications 1.0% 0.5% tamponade
Hamburg[24] 2010	Number of subjects	64 total (all paroxysmal)	(No comparator group)
Pulmonary vein isolation achieved acutely	100%
Procedure time	3.0 (2.5- 3.8) 1.5 hours
Fluoroscopy time	24 (12-34) minutes
Clinical success (Freedom from AF)	81% at 12 months
Safety	Total complications 0%
Hamburg[25] 2009	Number of subjects	65 total Paroxysmal 43 Persistent 22
Pulmonary vein isolation achieved acutely	95% (remainder completed manually)
Procedure time	3.3 ± 0.7 hours
Fluoroscopy time	17 ± 7 minutes
Clinical success (Freedom from AF )	73% at 8 months 76% Paroxysmal 78% persistent
Safety	Total complications 5% Tamponade 1.5%
Prague[26] 2009	Number of subjects	22 total All paroxysmal	16 total (registry cohort) All paroxysmal
Pulmonary vein isolation achieved acutely	100%	100%
Procedure time	3.5 ± 0.5 hours	4.2 ± 1.0 hours
Fluoroscopy time	15 ± 5 minutes	27 ± 9 minutes
Clinical success (Freedom from AF )	91% at 5 ± 1 month	81% at 9 ± 3 month
Safety	Total complications 0%	Total complications 0%
Multicenter group (France, Germany, Italy, Prague, USA)[27] 2008	Number of subjects	40 total Paroxysmal 29 Persistent 11	(No compartor group)
Pulmonary vein isolation achieved acutely	100%
Procedure time	2.8 ± 1.5 hours
Fluoroscopy time	64 ± 33 minutes
Clinical success (Freedom from AF )	98% at 12 months
Safety	Total complications 5% Tamponade 5% (nil else)

References

1. "Use of the Hansen Medical System in Patients With Atrial Fibrillation". National Institutes of Health. 2010-12-17. Retrieved 2011-03-21.
2. "Hansen Medical Reports Fourth Quarter and Full Year 2010 Results" (Press release). Hansen Medical. 2011-02-23. Retrieved 2011-03-21.
3. Hlivak P, Mlcochova H, Peichl P, Cihak R, Wichterle D, Kautzner J (2010-11-23). "Robotic Navigation in Catheter Ablation for Paroxysmal Atrial Fibrillation: Midterm Efficacy and Predictors of Postablation Arrhythmia Recurrences". Journal of Cardiovascular Electrophysiology (Wiley-Blackwell) 22: 534–540. doi:10.1111/j.1540-8167.2010.01942.x. ISSN 1540-8167. OCLC 50157846.
4. Willems S, Steve D, Servatius H, Hoffman B, Drewitz I, Llerleile K, Ali Aydin M, Wegscheider K, Salukhe T, Meinertz T, Rostock T (June 2010). "Persistence of Pulmonary Vein Isolation After Robotic Remote-Navigated Ablation for Atrial Fibrillation and its Relation to Clinical Outcome". Journal of Cardiovascular Electrophysiology (Wiley-Blackwell) 21 (10): 1–6. doi:10.1111/j.1540-8167.2010.01773.x. ISSN 1540-8167. OCLC 50157846. PMID 20455974.
5. Duncan E, Liew R, Goromonzi F, Richmond L, Baker V, Thomas G, Tayebjee M, Finlay M, Abrams D, Dhinoja M, Earley M, Sporton S, Schilling R (2010). "A Randomized Controlled Trial of Catheter Ablation of AF Comparing Manual and Robotic Navigation". Heart Rhythm (Elsevier) 7 (5): 339. ISSN 1556-3871. OCLC 55803866.
6. Di Biase L, Wang Y, Horton R, Gallinghouse J, Mohanty P, Sanchez J, Patel D, Dare M, Canby R, Price L, Zagrodzky J, Bailey S, Burkhardt D, Natale A (December 2009). "Ablation of Atrial Fibrillation Utilizing Robotic Catheter Navigation in Comparison to Manual Navigation and Ablation: Single-Center Experience". Journal of Cardiovascular Electrophysiology (Wiley-Blackwell) 20: 1–8. doi:10.1111/j.1540-8167.2009.01570.x. ISSN 1540-8167. OCLC 50157846.
7. Kanagaratnam P, Koa-Wing M, Wallace DT, Goldenberg AS, Peters NS, Davies DW (2008). "Experience of robotic catheter ablation in humans using a novel remotely steerable catheter sheath". J Interv Card Electrophysiol 21: 19–26. doi:10.1007/s10840-007-9184-z. PMC 2262917. PMID 18202905.
8. Steven D, Rostock T, Servatius H, et al. (2008). "Robotic versus conventional ablation for common-type atrial flutter: a prospective randomized trial to evaluate the effectiveness of remote catheter navigation". Heart Rhythm 5: 1556–1560. doi:10.1016/j.hrthm.2008.08.028.
9. Di Biase L, Natale A, Barrett C, et al. (2009). "Relationship between catheter forces, lesion characteristics, "popping," and char formation: experience with robotic navigation system". J Cardiovasc Electrophysiol 20: 436–440. doi:10.1111/j.1540-8167.2008.01355.x.
10. Kautzner J, Peichl P, Cihak R, Wichterle D, Mlcochova H (2009). "Early experience with robotic navigation for catheter ablation of paroxysmal atrial fibrillation". Pacing Clin Electrophysiol 32 (Suppl 1): S163–S166. doi:10.1111/j.1540-8159.2008.02277.x.
11. Koa-Wing M, Kojodjojo P, Malcolme-Lawes LC, et al. (2009). "Robotically assisted ablation produces more rapid and greater signal attenuation than manual ablation". J Cardiovasc Electrophysiol 20: 1398–1404. doi:10.1111/j.1540-8167.2009.01590.x.
12. Steven D, Rostock T, Servatius H, et al. (2008). "Robotic versus conventional ablation for common-type atrial flutter: a prospective randomized trial to evaluate the effectiveness of remote catheter navigation". Heart Rhythm 5: 1556–1560. doi:10.1016/j.hrthm.2008.08.028.
13. Di Biase L, Wang Y, Horton R et al. Ablation of Atrial Fibrillation Utilizing Robotic Catheter Navigation in Comparison to Manual Navigation and Ablation: Single-Center Experience. J Cardiovasc Electrophysiol 2009.
14. Steven D, Servatius H, Rostock T et al. Reduced Fluoroscopy During Atrial Fibrillation Ablation: Benefits of Robotic Guided Navigation. J Cardiovasc Electrophysiol 2009.
15. Wazni OM, Barrett C, Martin DO et al. Experience with the Hansen Robotic System for Atrial Fibrillation Ablation-Lessons Learned and Techniques Modified: Hansen in the Real World. J Cardiovasc Electrophysiol 2009.
16. Wazni OM, Barrett C, Martin DO et al. Experience with the Hansen Robotic System for Atrial Fibrillation Ablation-Lessons Learned and Techniques Modified: Hansen in the Real World. J Cardiovasc Electrophysiol 2009.
17. Di BL, Wang Y, Horton R et al. Ablation of Atrial Fibrillation Utilizing Robotic Catheter Navigation in Comparison to Manual Navigation and Ablation: Single-Center Experience. J Cardiovasc Electrophysiol 2009.
18. Steven D, Servatius H, Rostock T et al. Reduced Fluoroscopy During Atrial Fibrillation Ablation: Benefits of Robotic Guided Navigation. J Cardiovasc Electrophysiol 2009.
19. Willems S, Steven D, Servatius H et al. Persistence of Pulmonary Vein Isolation After Robotic Remote-Navigated Ablation for Atrial Fibrillation and its Relation to Clinical Outcome. J Cardiovasc Electrophysiol 2010.
20. Bhargava M, Di Biase L, Mohanty P et al. Impact of type of atrial fibrillation and repeat catheter ablation on long-term freedom from atrial fibrillation: Results from a multicenter study. Heart Rhythm 2009.
21. Hunter RJ, Berriman T, Diab I, et al. (2010). "Long term efficacy of catheter ablation for AF: impact of additional targeting of fractionated electrograms". Heart 96: 1372–1378. doi:10.1136/hrt.2009.188128.
22. Hlivak P, Mlcochova H, Peichl P, Cihak R, Wichterle D, Kautzner J (2011). "Robotic navigation in catheter ablation for paroxysmal atrial fibrillation: midterm efficacy and predictors of postablation arrhythmia recurrences". J Cardiovasc Electrophysiol 22: 534–540. doi:10.1111/j.1540-8167.2010.01942.x.
23. Di Biase L, Wang Y, Horton R et al. Ablation of Atrial Fibrillation Utilizing Robotic Catheter Navigation in Comparison to Manual Navigation and Ablation: Single-Center Experience. J Cardiovasc Electrophysiol 2009.
24. Wazni OM, Barrett C, Martin DO et al. Experience with the Hansen Robotic System for Atrial Fibrillation Ablation-Lessons Learned and Techniques Modified: Hansen in the Real World. J Cardiovasc Electrophysiol 2009.
25. Schmidt B, Tilz RR, Neven K, Julian Chun KR, Furnkranz A, Ouyang F (2009). "Remote robotic navigation and electroanatomical mapping for ablation of atrial fibrillation: considerations for navigation and impact on procedural outcome". Circ Arrhythm Electrophysiol 2: 120–128. doi:10.1161/circep.108.818211.
26. Kautzner J, Peichl P, Cihak R, Wichterle D, Mlcochova H (2009). "Early experience with robotic navigation for catheter ablation of paroxysmal atrial fibrillation". Pacing Clin Electrophysiol 32 (Suppl 1): S163–S166. doi:10.1111/j.1540-8159.2008.02277.x.
27. Saliba W, Reddy VY, Wazni O, et al. (2008). "Atrial fibrillation ablation using a robotic catheter remote control system: initial human experience and long-term follow-up results". J Am Coll Cardiol 51: 2407–2411. doi:10.1016/j.jacc.2008.03.027.