TAVI - Transcatheter Aortic Valve Implantation

An extensive presentation on the upcoming catheter based aortic valve implantation including a future perspective of TAVI

1. Transcatheter Aortic Valve Implantation (TAVI) Dr. K. Srikanth DNB (Cardiothoracic Surgery) Resident – 3 rd year Narayana Hrudayalaya , Bangalore 31.12.2019

2. Outline of presentation History Anatomy (TAVI specific) Indications & Contra-indications Valve options Technique Complications NH experience Future direction

3. Why should you know about TAVI? Structural Heart Interventions are coming up in a big way Surgeons of the future need to be ‘interventional surgeons’ In the west, a good number of TAVIs are performed by surgeons, so you might be performing TAVI one day! To deal with the complications of such procedures

4. History of TAVI First balloon aortic valvotomy – 1988 by Dr. Alain Cribier Recurrence of symptoms due to restenosis in 6-8 months 1993 – Alain Cribier demonstrated in cadaveric hearts that a stent across the aortic valve was well anchored within the aortic annulus, there was no recoil and the coronary ostia were unobstructed

5. First drawing by Cribier in 1994 conceptualising TAVI

6. First human implantation – 2002 On April 16, 2002 , at the Charles Nicolle University Hospital in Rouen, France, the Interventional Cardiologist, Professor Alain Cribier performed the first transcatheter aortic valve implantation procedure in the world. He used a  Percutaneous Valve Technology  ( PVT ) percutaneous heart valve.

7. A 57-year old man in cardiogenic shock secondary to severe aortic stenosis received the transcatheter heart valve on compassionate basis Because of hemodynamic instability and multiple co-morbidities, surgeons refused to operate. Severe peripheral arterial disease forced the team to implant the valve using an antegrade approach with transvenous and transseptal puncture First-in-human transcatheter aortic valve implantation using a 24Fr catheter delivery system that housed a 23-mm bovine pericardial stent valve After valve implantation, the transvalvular aortic gradient was less than 10 mmHg and the aortic valve area increased to 1.7 cm 2 . These excellent results were never before observed with balloon aortic valvuloplasty .

8. This patient had a stormy post-procedure period ( pulm embolism, sepsis, limb ischemia) and a satisfactory follow up period with good hemodynamic & echo parameters until he succumbed to sepsis 17 weeks later secondary to mid thigh amputation stump infection due to pre-existing PVD Thereafter in Rouen on compassionate basis, the first series of 40 patients underwent implantation of a modified model heart valve, the Cribier -Edwards valve (equine pericardium), using an antegrade transseptal approach Antegrade transcatheter aortic valve implantation was technically challenging and caused hemodynamic instability from mitral valve tethering and injury made the procedure too risky . As a result since 2004, retrograde transcatheter aortic valve implantation via the femoral artery ( transfemoral ) and apex of the heart ( transapical ) proved to be more reproducible and safer

9. Indications of TAVI - What do the latest international guidelines recommend?

10. Management algorithm for Severe AS – ESC/EACTS (2017) guidelines

11. ESC/EACTS (2017) TAVR guidelines

12. ESC/ EACTS (2017) guidelines (TAVR vs SAVR)

13. AHA (2017) TAVR guidelines

14. Contraindications to TAVI

15. Anatomy for TAVI

16. The relationship of the left ventricular outflow tract to the aortic root differs between elderly and younger patients with a more acute angle (90-120 degrees) being encountered in the elderly group For the purposes of transcatheter aortic valve implantation (TAVI), the “aortic valve annulus” corresponds to a virtual ring formed by joining the basal attachment points of the leaflets within the left ventricle The aortic valve plane represents the inlet from the left ventricular outflow tract into the aortic root

17. Pre-procedure investigations Transthoracic echocardiography (TTE ) T ransesophageal echocardiography (TEE ) – earlier used for TAVI but underestimated the annulus size causing paravalvular leak (PVL) Multi-Slice ECG-gated Computed Tomography (MSCT ) - most informative and gold standard Contrast aortography Magnetic R esonance I maging (MRI)

18. What to look for in MDCT? Atherosclerotic burden [A ] Vessel tortuosity or ‘bending’ [B ] Calcification [ C] D iameter [D]

19. ‘Skin to valve’ analysis using MDCT for TAVI planning

20. Access route decision

21. Coronary ostial height from annular plane Ideal fluoro projection for valve deployment

22. Aortic annulus concept – Natural aortic annulus is oval in shape which becomes circular after deployment of a valve

23. Aortic annulus measurement

24. Comprehensive CT analysis for TAVI – Key to a successful outcome What are the elements of a TAVI CT study?

25. Valve ‘ over’sizing In general balloon-expandable prostheses are oversized 10-20 % relative to the aortic annulus This ‘planned’ oversizing helps to anchor the prosthesis which is sutureless . In addition, they assume a circular shape irrespective of the native annulus, in contrast to self-expanding platforms which ‘mould’ to the native annulus anatomy.

26. Summary of TAVI decision-making Risk criteria (based on STS/ EuroSCORE ) – at present, TAVI is recommended only for high risk patients (both AHA & ESC guidelines) Anatomical criteria – as discussed earlier Patient criteria - Co-morbidities are frequent in the typical population being considered for TAVI. A multidisciplinary assessment of the patient in the light of these factors is essential for the appropriate selection and safe conduct of a TAVI program Heart Team - cardiac surgery, cardiac anaesthesia, interventional and general cardiologists, imaging specialists (from cardiology and/or radiology), geriatricians and any other relevant area (e.g. nephrology, neurology)

27. Fraility index -   The appearance of frailty can be perceived by experienced clinicians. Objectively defining this physiological state, however, remains challenging.  In practice a combination of subjective evaluation and objective parameters such as the Katz score or Charlson comorbidity index, grip strength ( assessed with a dynamometer), validated walking test and albumin are used. Futility index - Patients at extreme risk who have a limited life expectancy (arbitrarily considered to be <1 year) or who are unlikely to gain any meaningful symptomatic relief due to significant comorbidity, should not undergo this procedure due to futility.  Operator and institutional criteria - Operator learning curves for SAPIEN from the PARTNER trial suggest an average of 26 cases for transfemoral TAVI and between 30 and 45 cases for trans-apical TAVI were needed to achieve a plateau in adverse events

28. TAVI Hardware B ioprosthetic valve prosthesis (mechanical valves can’t be used because of the inability to ‘crimp’ it) D elivery catheter L oading system Deployment mechanisms - self-expansion , balloon expansion and inflatable platforms Ancillary device facilitators – sheaths, guidewires , balloons

29. Balloon Vs self-expandable valves

30. Sheaths - These have progressively reduced in size from 24-26 Fr (8.0-8.7mm) to 14-16Fr for balloon-expandable prostheses and 18Fr (6.0mm) for self-expanding prostheses Guidewires - All the wires for TAVI are of exchange length (260cm+) and consist of a solid proximal core with a distal atraumatic soft tip (to prevent LV perforation) Balloons - These have a length of 4-5cm so as to provide an anchor and eliminate movement during inflation which is typically performed at 4-6atm. Newer designs incorporate a waist to enhance anchoring further.

31. Devices available Currently there are 12 percutaneous prosthetic aortic valve systems (8 for transfemoral use, 4 for trans-apical use) that have  Conformité Européenne  (CE) approval and 2 that have Federal Drug Administration (FDA) approval for use in Europe and the North America respectively . There are two generations of TAVI valves as of today - Medtronic CoreValve , Edwards SAPIEN THV and Edwards SAPIEN XT were considered early first generation devices, whereas Edwards SAPIEN 3 (Edwards Lifesciences ), LOTUS valve system (Boston Scientific, Natwick , Massachusetts, USA) and Medtronic Evolut R (Medtronic) were considered newer second generation devices. R3 concept - re-sheathable, re- positionable , and retrievable devices are considered to be ideal

32. SAPIEN 3 Valve (Edwards Lifesciences ) Bovine pericardium Balloon expandable Lowest profile D edicated outer skirt to minimise PVL R ow of large cells to allow easier coronary access Approved for femoral and apical access

33. Medtronic Corevalve Self-expanding valve Useful for small annuli (18-20mm), 23mm valve can be deployed as it is supra-annular

34. St. Jude medical Portico valve

35. Jena valve Direct Flow valve Balloon-expandable valve Out of market Trans-femoral and apical routes Only CE approved valve for pure AR as it has nitinol hooks which anchor to the native leaflets

36. LOTUS Edge valve Trans-femoral and trans-aortic routes 14 Fr delivery sheath – 2 nd generation 21mm-29mm valve sizes Rapid pacing not required Fully repositionable, retrievable

37. Medtronic Engager Only for trans-apical use

38. Steps of Trans-femoral TAVI

39. Anesthesia Increasingly procedures are being performed under local anesthesia with or without sedation General anaesthesia and intubation is thus not mandatory for all cases and is typically reserved for non-femoral approaches or anticipated complex femoral procedures Currently half of all transcatheter procedures are performed under general anesthesia worldwide Routine pre-procedural antibiotic prophylaxis is administered

40. Contra-lateral access The majority of practitioners use a right-sided transfemoral approach for the TAVI sheath and delivery system with secondary access from the left femoral artery for a pigtail catheter to be used for supra-aortic angiography or, vice-versa due to arterial quality and lack of tortuosity . Alternative secondary access from the radial artery is performed by some practitioners.

41. Puncture Heparin is administered to target an ACT of 250-300sec for the procedure This should always be image-assisted to ensure the puncture point is in common femoral artery segment over the femoral head and avoiding the femoral bifurcation. Fluoroscopy and antegrade contrast acquisition from a catheter, typically an internal mammary catheter, placed at the distal aortic bifurcation is performed. Alternative or supplementary techniques such as digital subtraction angiography or ultrasound can also be used. 

42. Pre-closure This can be performed with a variety of dedicated devices such as ProGlide (Abbott Vascular, Redwood City, CA), Perclose or ProStar (Abbott Vascular Inc , Santa Clara, CA), all of which can be placed either as a single device or as a pair to give a cruciform configuration.  Preclose demo video

43. Sheath insertion Insertion of a stiff guidewire allows for insertion of the TAVI delivery sheath by providing support and straightening any iliofemoral tortuosity For challenging anatomy due to peripheral arterial disease a balloon-expandable sheath may be necessary

44. Prosthesis preparation The majority of prostheses require on-table preparation which involves crimping the prosthesis onto the delivery system Care is required to ensure the prosthesis loaded in the correct configuration to avoid an inverted valve being deployed in error. Newer generations of devices may come pre-packaged on delivery systems. Valve crimping video

45. Temporary pacemaker implantation Temporary pacing is required for pre-dilation, post-dilation, or prosthesis deployment under rapid pacing to prevent device ejection by systolic contraction In addition, it serves as protection against the potential development of bradyarrhythmia following TAVI. The right internal jugular vein or femoral vein is used typically. The temporary pacing wire is retained following the procedure for varying periods of time with self-expanding valve prostheses Rapid pacing has also been used to reduce ventricular tearing and haemorrhage during sheath removal for trans-apical Pacing rates must be high enough to cause a fall in systolic BP and this typically occurs >160-220bpm.

46. Valve crossing The calcified aortic valve can be a challenge to cross. The most frequently used technique involves probing the aortic valve in a systematic clockwise or anti-clockwise fashion using a standard straight-tipped wire through an Amplatz catheter in the LAO projection Alternative catheters such as an internal mammary or Judkins right (JR) can be used dependent on the horizontal lie of the aortic root A pigtail catheter is placed in the non-coronary sinus of Valsalva and aortic root angiography is used to determine the position of equipment relative to the coronary cusps . The aortic annular plane (the nadirs of the non, right and left coronary cusp leaflets) should be perpendicular to the valve device and co-axially aligned. Rotational angiography to find a projection with all three aortic valve leaflets superimposed equally helps to ensure optimal deployment precision .

47. Pre-dilation Systematic pre-implant dilation to prepare the aortic landing zone for TAVI is performed in patients with severe calcification. If performed this involves right ventricular pacing at rates 160-180bpm for up to 20 seconds in order to reduce left ventricular stroke volume and allow several seconds of balloon inflation. Importantly the size of the balloon should not exceed the minimum aortic annulus diameter from the CT scan.

48. Positioning Correct implantation depth is a critical feature of a successful implant . Accurate placement of the prosthesis requires visualization of both the aortic annulus plane and that of the device delivery catheter overlap perpendicularly. Co- axiality of the prosthesis/delivery system and the center of the aortic valve is important. Aortic root-LVOT angulation > 90 or <45 degrees can make prosthesis deployment uneven . Traditionally there are two methods used to determine that the device is coaxial with the annulus: the line of perpendicularity method and the centerline method. 

49. A more accurate system has been developed which can be applied to all TAVI systems and involves the use of a fusion of fluoro and CT to create a ‘ double S curve ’. In essence this is where the annulus and delivery system ‘ perpendicularity ’ curves intersect. This will frequently be in the RAO caudal projection as opposed to the more traditional LAO cranial projection

50. Post-valve deployment assessment An assessment of the presence of PVL should be made with echo and/or angiography. In addition, the AR index can be calculated ([DBP-LVEDP]/SBPx100, values <25 imply a good prognosis with a mortality at 1 year of 16.7% vs 46% for values > 25 at 1 year p<0.001)

51. Post-dilation Post-dilatation may be needed in about 25 % of cases in order to achieve optimal prosthesis frame expansion and reduce residual PVL. It is successful in roughly half of cases is also associated with an increased risk of peri -procedural stroke. If unsuccessful, a TAV-in-TAV may need to be performed

52. Haemostasis and vessel closure This can be via elective open surgical repair or by fashioning knots with percutaneous pre-closure suture-based device Although these percutaneous devices weren’t originally designed for TAVI they now have CE approval and are able to close arteriotomies up to 24Fr in diameter.  TAVI video

53. Anticoagulation post-TAVI

54. Alternative access sites for TAVI

55. SUBCLAVIAN/TRANSAXILLARY This the most frequent non-femoral access point used. Typically performed via a surgical cut-down when in the subclavian portion. If transaxillary it can also be performed percutaneously with pre-closure sutures most frequently into the proximal third of the axillary artery. The short distance is an advantage but the acute angulation induced by the subclavian -aortic junction makes the sheath prone to kinking Dissection and bleeding can be challenging to control even with open surgical access. A left-sided approach is selected in >95% of cases due to this offering a more favourable alignment of the prosthesis with the native valve. The presence of a patent LIMA graft is considered a relative contra-indication.

56. TRANS-AORTIC A right anterior mini-thoracotomy is used for patients with a right sided ascending aorta or patent coronary bypass grafts and a mini-J sternotomy for middle or left-sided ascending aortas and a deep anatomical location or pre-existing lung disease The aorta is inspected to avoid areas of calcification. Using a purse-string suture, needle puncture and access with a haemostatic sheath is obtained . The puncture is made with a minimum of 6cm for CoreValve and 8cm for SAPIEN platforms. The valve is then deployed in the same way as via the transfemoral approach Compared to the transapical route advantages include faster mobilization and avoidance of an LV apical scar which can sometimes result in a pseudoaneurysm . Compared to the axillary route advantages include avoidance of significant peripheral vascular disease and potential for occlusion of the vertebral and, in those with CABG, the internal mammary artery . ( Video)

57. TRANS-CAROTID This is performed under local anaesthesia with cerebral oximetry monitoring. Satisfactory vessel size and vessel quality are critical determinants for efficacy and safety as is an anatomically complete Circle of Willis. The short distance and provision of a direct coaxial approach to the aortic valve is an advantage. Stroke is the main disadvantage.

58. TRANS-APICAL This is performed via a left anterolateral thoracotomy followed by needle puncture of the apex through a pledgeted purse-string suture A dedicated haemostatic sheath is applied and the valve deployed in a similar fashion to the transfemoral approach thereafter. The advantages of this route are the short distance to the aortic valve and antegrade delivery allowing for more precise control, disadvantages include haemorrhage, tamponade and left ventricular pseudoaneurysm .  Contra-indications include the presence of left ventricular thrombus and/or a ventricular aneurysm. Dedicated apical closure devices have been developed and are beginning to enter clinical use (Video)

59. TRANS-CAVAL This percutaneous route has been used in those who lack conventional access options. It is technically challenging and there is a significant ‘learning curve’. The procedure consists of femoral vein access and puncture across the inferior vena cava into the abdominal aorta using a coronary guidewire to apply electrocautery energy and create a caval -aortic fistula. The remaining steps up to deployment are conducted in the conventional way and then the fistula is closed with a percutaneous device such as an Amplatz PDA occluder

60. TRANS-SEPTAL The original method of access during the pioneering days it involves femoral venous access , trans-septal puncture and an anterograde approach to the aortic valve. Although of historical interest, due to the potential for entanglement within the mitral valve apparatus this method has been abandoned.

61. Complications of TAVI Cardiovascular complications Non-cardiovascular complications

62. Cardiovascular complications - Paravalvular Leak (PVL) The potential mechanisms for PVL includes heavy calcification, malpositioning (too low resulting in PVL over the pericardial skirt or too high leading to PVL by inadequate annulus sealing) , dysfunction of one of the leaflets, a very ellipitical annulus, a small valve relative to annulus ( referred to as the cover index) and an under-expanded valve While first generation prosthetic valves together with a reliance on echocardiographic sizing of the aortic annulus in the early days was associated with a broad frequency of at least moderate severity of 10-30%; nowadays the use of CT imaging and prosthesis designs to improve annular sealing through conformability and radial force have reduced this to broadly under 10%

63. If the mechanism is valve malposition then a second valve-in-valve procedure is warranted. If the leak is due to under-expansion then post-dilatation is warranted. Prevention of paravalvular regurgitation requires the prosthesis to be conformable, have accurate annular dimensions, and sufficient radial force. However, sealing occurs at more than just the annulus and future improvements may be contingent on 3D modelling programmes that predict the ‘seal’ based on the valve type, individual aortic root anatomy together with the extent and distribution of calcium. Second generation TAVI valve designs have helped to mitigate against moderate/severe regurgitation compared to first generation valves 

64. Stroke The mechanism for this much-feared peri -procedural complication is embolism (either from atheromatous and calcific material or thrombus either related to atrial fibrillation or endovascular manipulation during the procedure ) Diffusion-weighted brain MRI imaging, particularly with 3-Tesla machines, detects perfusion deficits in the vast majority of patients undergoing TAVI whether via the femoral or transapical approach. These are not associated with any clinically-measurable neurological deficit and the long-term meaning of this imaging finding although concerning is uncertain currently. Nevertheless, cerebral protection devices have also demonstrated macroscopic debris (consisting of valve tissue, thrombus, collagenous tissue, and calcium) in the vast majority of procedures.

65. The challenge thus posed has fuelled the development of cerebral protection devices that either deflect debris away from the head and neck vessels or capture material in toto . Commercially available devices include Embrella, TriGuard , Embol -X devices Triguard video Embrella video

66. Conduction abnormalities Atrial fibrillation - one-third of patients with increasing left atrial size and a transapical approach being independent predictors T emporary and permanent conduction abnormalities particularly left bundle branch block due to the proximity of the LVOT portion of the device to the left bundle branch LBBB alone (i.e. if no permanent pacemaker is implanted) is not associated, in the majority of observational studies, with procedural mortality The frequency of new LBBB after TAVI is 35-35% with CoreValve and 10-30% with SAPIEN.

67. Predictors of the need for permanent pacemaker implantation include pre-existing LBBB and left axis deviation, right bundle branch block, the thickness of the non-coronary leaflet, depth of device implantation from the non and left coronary leaflets, and septal thickness The depth of implantation is the only modifiable factor and reducing the depth of implant to less than 5mm also reduced the incidence of new conduction abnormalities and pacemaker implantation. The permanent pacemaker implantation rate for CoreValve is 13-39% and 4-10% with SAPIEN.

68. VASCULAR INJURY This is related to sheath size and can include arterial dissection, perforation, failed percutaneous closure, and arterial avulsion. A meta-analysis of 16 published trials gave a range of 5-23 % of vascular access site complications Temporary control of iliofemoral vascular tear or rupture during sheath insertion or removal may be obtained by temporary balloon occlusion from the contralateral femoral artery  until open surgical managemen t is perfomed

69. Coronary obstruction/ occlusion Coronary obstruction is a critical complication caused by native leaflets and device skirt overlapping the coronary ostia . The heights of the ostia are variable and pre-procedural planning is the key element in maintaining safe clearance. Obstruction occurs most frequently with the left coronary and a height of <12mm and/or sinus of Valsalva <30mm. It seems to occur particularly if a valve-in-valve procedure is performed The left main ostium is the most frequently reported coronary vessel to be obstructed , and when recognised can be rescued with immediate PCI. Importantly , unexplained hypotension (as opposed to ECG signs of ischemia) may be the only clinical sign.

70. PERICARDIAL EFFUSION AND TAMPONADE This complication is due to cardiac chamber or aortic annulus perforation and most frequently related to temporary pacing wire perforation of the right ventricle or guidewire or catheter perforation of the left ventricle, particularly with stiff equipment. Most events occur within 24hrs. Mortality is mainly associated with left-sided perforation (annular or ventricular) and tamponade . Frequently, this requires emergency sternotomy

71. AORTIC ANNULAR OR ROOT RUPTURE Rupture due to the radial force of the prosthesis or balloon dilation can occur at the annulus/root or LVOT. Rarely encountered, if it occurs it is frequently catastrophic on the operating table. It is associated with area oversizing >20% and/or asymmetric calcium extending into the LVOT particularly below the right coronary leaflet. Balloon-expandable prostheses are typically involved rather than self-expanding platforms Surgical intervention is inevitable although rare reports of TAV-in-TAV have been performed

72. Other less frequent complications Valve malpositioning / embolization Valve dysfunction Valve thrombosis/ endocarditis Delayed embolisation

73. Non-cardiovascular complications Acute kidney injury – due to contrast and embolic calcium shower Hemolysis (secondary to patient-prosthesis mismatch) Acquired von- Willibrand disease – due to shear stress of vWF on the valve Sepsis Radiation injury

74. Where does TAVR stand today? PARTNER 3 trial results (published in September 2019) Among low-risk patients with aortic stenosis, TAVR was superior to SAVR at preventing death, stroke, or rehospitalization at 1 year. TAVR was also associated with a lower incidence of stroke and atrial fibrillation, and a shorter hospital length of stay compared with SAVR. TAVR was also associated with a larger improvement in quality of life compared with SAVR. There was a numerical increase in the need for new permanent pacemaker within 30 days in the TAVR group (6.5% with TAVR vs. 4.0% with SAVR); however, this difference was not statistically significant. Mild paravalvular aortic regurgitation occurred at a higher incidence in the TAVR group. The incidence of moderate to severe aortic regurgitation was rare (<1%) and similar between treatment groups.

75. SAPIEN Vs CoreValve (CHOICE study) The Comparison of Transcatheter Heart Valves in High Risk Patients With Severe Aortic Stenosis (CHOICE) trial is the only head-to-head comparison of CoreValve with SAPIEN XT (n=241). Using a composite endpoint for device success (successful vascular access, delivery, deployment and retrieval of delivery system, correct positioning of the device, intended performance according to echo [aortic valve area >1.2cm 2 , and mean aortic valve gradient <20mmHg or peak velocity<3m/s], and only one valve implanted in the proper anatomical location) the result showed that the balloon-expandable SAPIEN XT had a higher frequency of success 

76. Newer advances in TAVI

77. TAV-in-SAV The first clinical case of TAVI for a degenerate surgical bioprosthesis was performed with a CoreValve in 2007 Currently this procedure is restricted to those for whom re-do surgery poses a high risk as judged by the multidisciplinary Heart team. Although leaflet deterioration leading to stenosis or regurgitation represent the mechanisms for surgical valve dysfunction it is important to know the precise mode of surgical valve failure. Thrombosis and endocarditis are contraindications to TAVI and stenosis (as opposed to regurgitation) is associated with worse procedural outcomes. Key aspects include ascertaining the true inner diameter of the base ring in stented valves (as this is a rigid non- expansile portion of the valve), the degree and location of any calcification, and the potential risk of coronary ostial occlusion Pre-dilatation is not recommended but the remaining aspects of the percutaneous procedure are similar to a conventional TAVI procedure with good results from cumulative series of both SAPIEN and CoreValve platforms . Video

78. TAV-in-SAV for degenerated mitral bioprosthesis

79. A transcatheter valve inside a pre-existing TAV (TAV-in-TAV) is also possible in case of device malpositioning / degeneration TAVI for bicuspid aortic valve is considered a relative contraindication due to a preponderance of asymmetrical calcium, low coronary ostia and concurrent aortopathy affecting the ascending aorta (in which case TAVI is contraindicated). TAVI is being performed in such cases as well but the results are awaited

80. TAVI for isolated pure aortic regurgitation Percutaneous treatment of pure native aortic regurgitation is problematic because the pathologies that afflict the aortic valve also frequently involve the aortic root and ascending aorta mandating open surgical management . Furthermore , the absence of calcium in native regurgitation means that conventional balloon-expandable and self-expanding platforms are less able to anchor themselves securely within the aortic complex and the anchor points themselves may not be within the annulus. To date only limited numbers of patients have undergone TAVI and a large minority have had some degree of calcification in the aortic valvar complex

81. To overcome these obstacles two pigtails can be used to identify the annulus via the left and non-coronary sinuses (and thus more contrast is typically used than in aortic stenosis procedures). If the anchor points are not within the annulus the valve may shorten and lie within a supra-annular position. Excessive valve mobility is typically seen and can be countered during deployment by rapid pacing. Despite this precaution there is a higher incidence of valve-in-valve procedures (20 %) compared to TAVI in aortic stenosis. Careful anatomical planning is required particularly measurement of the ascending aorta as this may act as a fixation point. The JenaValve is a percutaneous prosthesis design via the transapical approach that has been approved specifically for native aortic regurgitation and had encouraging early results

82. Devices in the pipeline Centera (trans-femoral) Trinity  (motorised releasing device for accurate positioning) Colibri (pre-loaded device) Innovare (trans-apical) Optimum (minimal sutures, so larger EOA) Syntheon (fully automated release system) Biovalve (360 degree flexible delivery system) Edwards Helio -Dock – for pure AR

83. TAVI at NH First TAVI performed in September 2013 ( CoreValve was used) Total TAVIs performed upto date – 73 TAVIs in 2019 - 26 Spectrum of valves used at NH Valve used No. of cases Corevalve 37 Sapien 3 16 Portico 12 Meril Myval 7 Hydra 1

84. What does the future hold? Won- Keun Kim, Christian W. Hamm, The Future of TAVI,  European Heart Journal , Volume 38, Issue 36, 21 September 2017, Pages 2704–2707

85. Predicted indication for TAVI in 2025

86. References PCR-EAPCI Textbook www.pcronline.com chapter on TAVI Technical aspects of transcatheter aortic valve implantation ( TAVI) - An article from the E-journal of Cardiology Practice Vol . 14, N° 5 - 08 Mar 2016 YouTube videos Google images Individual company catalogues for valve information

87. Thank you