doi:10.1510/mmcts.2009.003939
Transapical transcatheter off-pump aortic valve implantation Jo¨rg Kempferta, Sven Lehmanna, Axel Linkeb, Ardawan Rastana, Arnaud Van Lindena, Johannes Blumensteina, Gerhard Schulerb, Friedrich W. Mohra, Thomas Walthera,* a
Department of Cardiac Surgery, Heartcenter University of Leipzig, Germany
b
Department of Cardiology, Heartcenter University of Leipzig, Germany Transapical aortic valve implantation (TA-AVI) is a new minimally invasive technique for beatingheart off-pump AVI in high-risk patients. The procedure involves antegrade AVI using an oversizing technique with direct access and accurate positioning of a stent based transcatheter xenograft. Procedural steps include placement of femoral arterial and venous access wires, anterolateral minithoracotomy, placement of an epicardial pacing wire and two apical purse-string sutures. Valve implantation is performed off-pump under fluoroscopic and echocardiographic guidance with rapid ventricular pacing. This new technology is a promising alternative for selected elderly high-risk patients and seems to be associated with good outcome and a minimal stroke risk.
Keywords: Aortic stenosis; Aortic valve; Minimally invasive; Transapical; Transcatheter Introduction Conventional aortic valve replacement (AVR) has evolved to a highly standardized technique resulting in excellent outcome (Table 1) w1–7x. However, due to the aging population, an increasing number of octogenarians now require surgical therapy for severe symptomatic aortic stenosis (AS). Patients with older age plus additional risk factors as indicated by high logistic EuroSCORE or STS-Score values may not be referred for conventional AVR w8, 9x despite a grave prognosis without intervention w10x. For this subgroup of high-risk patients a less invasive technique to treat AS might be beneficial.
with AS w11x. After initial enthusiasm it became quickly evident that this technique is associated with modest and short-lived clinical improvements only w12x. Thus, the technique of isolated BAV for high-risk patients was widely abandoned. The most disappointing problem of BAV, the recurrence of AS, was overcome by the development of valved-stents (Photo 1: Edwards SAPIEN prosthesis, Photo 2: Medtronic CoreValve prosthesis). In April 2002, the first transcatheter valve was implanted successfully in a high-risk patient with AS. At present three approaches are used to deliver these valvedstents: antegrade transapical, retrograde transfemoral and retrograde transsubclavian.
History During the mid-1980s balloon aortic valvuloplasty (BAV) was advocated for selected high-risk patients * Corresponding author. Universita¨t Leipzig, Herzzentrum, Klinik fu¨r Herzchirurgie, Stru¨mpellstr. 39, 04289 Leipzig, Germany. Tel.: q49 341 865 1424; fax: q49 341 865 1452. E-mail: [email protected] 2010 European Association for Cardio-thoracic Surgery
Surgical technique The optimal environment for transcatheter aortic valve implantation (TAVI) is a hybrid-OR (Photo 3) facilitating high-quality imaging (fixed fluoroscopy system) and providing all surgical equipment for a potential conversion to standard surgical techniques. 1
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939 Table 1. Outcome of octogenarians after conventional AVR w1–7x Author
Journal
City
n
Age
30-day mortality (%)
Roberts et al. w1x Melby et al. w2x Kolh et al. w3x Urso et al. w4x de Vincentiis et al. w5x Filsoufi et al. w6x Leontyev et al. w7x
Am J Cardiol 2007 Ann Thorac Surg 2007 Eur J Cardiothorac Surg 2007 J Heart Valve Dis 2007 Ann Thorac Surg 2008 J Am Geriatr Soc 2008 Ann Thorac Surg 2009
Dallas St. Louis Liege San Sebastian Milan New York Leipzig
196 245 220 100 345 231 282
83.0 83.6 82.8 82.1 82.0 83.0 82.0
10.0 9.0 9.0 8.0 7.5 5.2 9.2
Photo 1. SAPIEN valve: bovine pericardium (ThermaFix) within a balloon-expandable steel-stent.
Delineation of the aortic root geometry is essential before performing transapical aortic valve implantation (TA-AVI). Transesophageal echocardiography (TEE) is the most reliable tool to measure the diameter of the aortic annulus (Video 1, Photo 4) and to assess the pattern of native valve calcification (Video 2). Photo 2. CoreValve device: porcine pericardium within a selfexpanding nitinol frame.
In addition to preoperative TEE we usually perform a cardiac-CT (Photo 5) and an angio-CT (Video 3). The strength of the cardiac-CT is the ability to measure the distance between the left (Photo 6) and right coronary ostia (Photo 7) and the aortic annulus.
placed into the femoral vessel acting as a ‘safety-net’ (Video 4).
TA-AVI is usually performed under general anesthesia (short acting drugs) and guided by TEE and fluoroscopy. Prior to skin incision a percutaneous venous wire and a 6 F arterial sheath (that is needed anyhow for later root angiography over a pigtail catheter) are
A left anterolateral minithoracotomy is placed in the fifth or possibly sixth intercostal space (Schematic 1). After rib spreading some epicardial fatty tissue is excised and the pericardium is opened longitudinally. Then an epicardial pacing lead and the purse-strings
2
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
Video 2. TEE: short-axis view to assess the calcification pattern. Concentric calcification is ideal for TAVI whereas a fixed commissure may lead to a paravalvular leak.
Photo 3. Hybrid-OR at the Heartcenter University of Leipzig combining a high-quality fixed fluoroscopy system (as it is used in cathlabs) with sterility requirements and surgical equipment including a ‘pump’ on standby of a regular cardiac surgical OR.
Video 1. TEE: long-axis view demonstrating the anatomy of the LVOT and the aortic root and a mild mitral regurgitation.
(Prolene 2-0 with MH needle) are placed where care is needed to avoid the fatty tissue at the true apex (optimal area lies more to the antero-lateral aspect) and to take sufficiently deep bites (Video 5).
Photo 5. Cardiac-CT demonstrating the anatomy of the aortic root including the diameters of the aortic annulus, the bulbus and the sinutubular junction.
In the next step, angulation of the C-arm needs to be set in order to obtain a perpendicular view onto the aortic annulus (Video 6).
Video 3. Angio-CT: 3D-reconstruction of the aorta and the iliac arteries.
After the valve has been prepared (Video 7) the apex is punctured and a soft guidewire is placed into the ascending aorta (Schematic 2). Now a 14 F soft sheath is advanced over the stenotic aortic valve and a superstiff guidewire is anchored into the descending aorta (Video 8). Prior to sheath insertion TEE should exclude any interference of the wire with the mitral valve (Video 9).
Photo 4. Measurement of the diameter of the aortic annulus: including all cusp calcifications, at mid-systole from the insertion of the right coronary cusp at the junction between interventricular septum, aortic annulus and aortic root and the insertion of the left coronary cusp just opposite at the junction between the anterior mitral leaflet, aortic annulus and aortic root.
In the next step, balloon-valvuloplasty (Schematic 3, Video 10) is performed under rapid ventricular pacing (RVP) to temporarily reduce cardiac output. Now the 26 F-sheath is bluntly inserted, the dilator is retrieved and the valve delivery system is attached, and after carefully de-airing the system the prosthesis 3
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
Photo 6. Cardiac-CT: distance between the left coronary ostia and the aortic annulus.
Photo 7. Cardiac-CT: distance between the right coronary ostia and the aortic annulus.
is advanced to the level of the aortic annulus (Schematic 4, Video 11). By manipulating the stiff wire (slack/tension) the tilting of the valve within the aortic annulus is adjusted to obtain a coaxial position (Video 12). After carefully positioning the valve (target: one-third to one-half above the annulus) the prosthesis is deployed by active ballooning under RVP (Schematic 5, Video 13). After implantation the valve function is assed by angio (Video 14) and TEE (Video 15). Finally, the delivery system is retrieved and the apex is secured by the purse-strings (Video 16).
Results After the initial pioneering phase of TAVI results have now stabilized. Due to the lack of a sufficient scoring 4
Video 4. ‘Safety-net’. A percutaneous femoral wire is advanced into the right atrium under fluoroscopic or TEE guidance. In addition, a 6 F arterial sheath is placed into the femoral artery. The access side should be chosen according to potential calcifications or kinking seen on the angio-CT. This vascular access allows for rapid percutaneous cannulation in Seldinger technique and facilitates immediate conversion to the cardiopulmonary bypass if required.
system, results of different groups using different approaches and devices are hardly comparable. Furthermore, although not supported by any scientific data, most groups follow a ‘transfemoral first’ strategy that naturally leads to a higher risk profile in the trans-
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
Video 7. Preparation of the Edwards SAPIEN valve: crimping of the valve onto the delivery balloon, attachment of the pusher and the loader.
Schematic 1. Transapical access. An incision in the fifth or sixth intercostal space usually results in a good exposure of the left ventricular apex. In patients with small ventricles the incision should be placed in the mid-clavicular line, in case of enlarged ventricles more to the lateral aspect.
Video 5. Anterolateral minithoracotomy. Four pericardial staysutures allow for bilateral lung ventilation and enhance the exposure of the apex. Two purse-strings are placed using Prolene 2-0 with a large MH needle reinforced with five Teflon pledgets. Schematic 2. After apical puncture (into the direction of the patient’s right shoulder) a soft guidewire is advanced in an antegrade fashion across the stenotic aortic valve.
Video 6. Root angiography to check for a correct angulation of the fluoroscopic system (approximately LAO/cranial 108/108). All three valve cusps should be in one plane, the commissure between the left and right coronary cusp in the middle and the takeoff of the left coronary artery clearly visible.
apical group that has to be taken into account when comparing the results in regard to the access site. In accordance to the recommendations published by ESC and EACTS recently, patients are eligible for TAVI
Video 8. Using Seldinger technique a 14 F soft-tip sheath is advanced into the ascending aorta. Then, with the help of a right Judkins catheter, the superstiff guidewire is placed into the descending aorta with minimal manipulation around the aortic arch only.
in our institution if they are at higher age ()75 years) and presenting with additional risk factors: • STS-Score )10% or logEuroSCORE -20% • Re-do cases with patent LIMA to LAD 5
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
Video 9. TEE 3D-probe in X-plane mode confirming correct position of the guidewire in short-axis and simultaneously long-axis view.
Schematic 4. SAPIEN prosthesis within the aortic annulus.
Schematic 3. Balloon-valvuloplasty using a 20 mm balloon.
Video 11. Insertion of the 26 F-sheath and delivery of the valve to the aortic annulus.
Video 10. Balloon-valvuloplasty under rapid ventricular pacing (RVP: 180 beats/min).
• Porcelain aorta • History of chest radiation or mediastinitis • Degenerated aortic bioprosthesis (valve-in-a-valve) • Other factors (liver failure, severe immobility, hematological-, coagulation-disorders) At our center we do not believe in a ‘transfemoral first’ approach. Thus, all patients are individually discussed in an interdisciplinary team conference. Then optimal 6
Video 12. Tilting of the valve within the aortic annulus.
treatment strategy is selected for each individual patient. Nevertheless, there are factors to favor either one or the other approach. Transfemoral AVI without general anesthesia might be beneficial for patients presenting with severe respiratory dysfunction. On the other hand, in patients with small femoral vessels,
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
Video 14. Final result on angio: patent coronaries and a competent valve.
Video 15. TEE excluding any significant transvalvular or paravalvular leak.
Schematic 5. Valve implantation by active balloon inflation.
severe kinking or generally heavily calcified vessels, the transapical approach avoids potential vascular complications. At the time of writing, our personal experience included more than 200 high-risk elderly patients who underwent TA-AVI. Mean age was above 80 years with a mean STS-Score of 12"7% and a mean logEuroSCORE of 32"16%. All patients received an Edwards SAPIEN valve following an oversizing concept of at least 2 mm. Table 2 summarizes the outcome and the rate of perioperative complications.
Video 13. Valve deployment after a final angio control under RVP. A slow or stepwise balloon inflation allows for final adjustments if necessary.
Video 16. Retrieval of the delivery system, tying of the purse-strings and closure of the incision. Table 2. Outcome after TA-AVI (Leipzig results) Total ns240 30-day mortality Stroke Conversion to sternotomy Coronary problem Too low valve position Annular tear Valve embolization Rethoracotomy (bleeding) New onset of chronic dialysis Pacemaker implantation Wound infection Postoperative echo parameters: AV Pmean Mean regurgitation AV (grade) None (trace) 18 28
9.6% 1% 2% 2% 1% 1% – 2% 2% 4% 1% 6"3 (mmHg) 0.5"0.6 135 (56%) 90 (38%) 15 (6%)
7
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939 Table 3. Potential complications and ‘bail-out’ options Event
Possible solution
Valve deployed too low Valve deployed too high/coronary occlusion
Second valve-in-a-valve with a slightly higher position 1) If a guidewire can be placed, consider stent-implantation 2) If not, sternotomy and surgical bypass grafts beating-heart on-pump Re-ballooning might help 1) If one leaflet is not moving try mobilization by pigtail manipulation, wait until arterial pressure has fully recovered 2) If not successful consider second valve-in-valve implantation eventually slightly higher to avoid interference of the native aortic valve cusps 1) Low-dose epinephrine into the aortic root over the pigtail is often helpful 2) In case of persistent low-output convert to CPB using the ‘safety-net’ for reperfusion. Bridge with chest compressions.
Paravalvular leak ()grade 1q) Central leak ()grade 1q)
Hemodynamical instability
Potential intraoperative complications and ‘bail-out’ options Given the high-risk nature of this special patient subgroup any complication might occur anytime. To maximise patient safety, the procedure should be performed in a fully equipped hybrid-OR allowing for conversion to conventional surgery including all standard techniques. Placement of a femoral ‘safety-net’ w13x prior to skin incision ensures timely pump-support if required. In addition to all ‘hardware’ precautions, a good team coordination and communication is most important to professionally deal with any potential complications. Table 3 demonstrates typical intraoperative complications and ‘bail-out’ options.
Discussion TA-AVI has evolved as a standard and routine procedure to treat elderly patients with AS using a minimally invasive approach. Most groups advocate the percutaneous retrograde transfemoral approach as the first choice if feasible. At first glance this seems reasonable as this access is the least invasive but the rate of major vascular complications associated with a transfemoral technique is still substantial (;10%) and the complication rate associated with the apical approach in our experience is acceptably low (;1%). In addition, exact valve positioning is far more complicated when using a retrograde approach and seems to be associated with more manipulations around the (calcified) aortic arch. Hence, this might translate into a higher stroke rate. To date, there is no scientific evidence proving the superiority of one or the other of these approaches. Although current outcome of TAVI is acceptable given the risk profile of this high-risk subgroup of patients, we still lack a prospectively randomized trial proving 8
superiority of this new technique compared with the excellent outcome of conventional AVR. Thus, TAVI should be restricted to selected high-risk patients until there are more hard clinical data available.
Conclusion TA-AVI is an off-pump and minimally invasive procedure that has evolved to a promising alternative in selected elderly high-risk patients. The technique is feasible even in the presence of severe peripheral vascular disease, requires limited surgical trauma only and allows for exact antegrade valve positioning.
References w1x Roberts WC, Ko JM, Garner WL, Filardo G, Henry AC, Hebeler RF Jr, Matter GJ, Hamman BL. Valve structure and survival in octogenarians having aortic valve replacement for aortic stenosis (q/aortic regurgitation) with versus without coronary artery bypass grafting at a single US medical center (1993 to 2005). Am J Cardiol 2007;100: 489–495. w2x Melby SJ, Zierer A, Kaiser SP, Guthrie TJ, Keune JD, Schuessler RB, Pasque MK, Lawton JS, Moazami N, Moon MR, Damiano RJ. Aortic valve replacement in octogenarians: risk factors for early and late mortality. Ann Thorac Surg 2007; 83:1651–1656; discussion 1656–1657. w3x Kolh P, Kerzmann A, Honore C, Comte L, Limet R. Aortic valve surgery in octogenarians: predictive factors for operative and long-term results. Eur J Cardiothorac Surg 2007;31:600–606. w4x Urso S, Sadaba R, Greco E, Pulitani I, Alvarez L, Juaristi A, Goiti JJ. One hundred aortic valve replacements in octogenarians: outcomes and risk factors for early mortality. J Heart Valve Dis 2007;16:139–144. w5x de Vincentiis C, Kunkl AB, Trimarchi S,
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
w6x
w7x
w8x
w9x
Gagliardotto P, Frigiola A, Menicanti L, Di Donato M. Aortic valve replacement in octogenarians: is biologic valve the unique solution? Ann Thorac Surg 2008;85:1296–1301. Filsoufi F, Rahmanian PB, Castillo JG, Chikwe J, Silvay G, Adams DH. Excellent early and late outcomes of aortic valve replacement in people aged 80 and older. J Am Geriatr Soc 2008;56: 255–261. Leontyev S, Walther T, Borger MA, Lehmann S, Funkat AK, Rastan A, Kempfert J, Falk V, Mohr FW. Aortic valve replacement in octogenarians: utility of risk stratification with EuroSCORE. Ann Thorac Surg 2009;87:1440–1445. Iung B, Cachier A, Baron G, Messika-Zeitoun D, Delahaye F, Tornos P, Gohlke-Barwolf C, Boersma E, Ravaud P, Vahanian A. Decision-making in elderly patients with severe aortic stenosis: why are so many denied surgery? Eur Heart J 2005; 26:2714–2720. Pai RG, Kapoor N, Bansal RC, Varadarajan P.
w10x
w11x
w12x
w13x
Malignant natural history of asymptomatic severe aortic stenosis: benefit of aortic valve replacement. Ann Thorac Surg 2006;82:2116–2122. Varadarajan P, Kapoor N, Bansal RC, Pai RG. Clinical profile and natural history of 453 nonsurgically managed patients with severe aortic stenosis. Ann Thorac Surg 2006;82:2111–2115. Cribier A, Savin T, Saoudi N, Rocha P, Berland J, Letac B. Percutaneous transluminal valvuloplasty of acquired aortic stenosis in elderly patients: an alternative to valve replacement? Lancet 1986;1: 63–67. Bashore TM, Davidson CJ. Follow-up recatheterization after balloon aortic valvuloplasty. Mansfield Scientific Aortic Valvuloplasty Registry Investigators. J Am Coll Cardiol 1991;17:1188–1195. Kempfert J, Walther T, Borger MA, Lehmann S, Blumenstein J, Fassl J, Schuler G, Mohr FW. Minimally invasive off-pump aortic valve implantation: the surgical safety net. Ann Thorac Surg 2008;86:1665–1668.
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Transapical transcatheter off-pump aortic valve implantation Jo¨rg Kempferta, Sven Lehmanna, Axel Linkeb, Ardawan Rastana, Arnaud Van Lindena, Johannes Blumensteina, Gerhard Schulerb, Friedrich W. Mohra, Thomas Walthera,* a
Department of Cardiac Surgery, Heartcenter University of Leipzig, Germany
b
Department of Cardiology, Heartcenter University of Leipzig, Germany Transapical aortic valve implantation (TA-AVI) is a new minimally invasive technique for beatingheart off-pump AVI in high-risk patients. The procedure involves antegrade AVI using an oversizing technique with direct access and accurate positioning of a stent based transcatheter xenograft. Procedural steps include placement of femoral arterial and venous access wires, anterolateral minithoracotomy, placement of an epicardial pacing wire and two apical purse-string sutures. Valve implantation is performed off-pump under fluoroscopic and echocardiographic guidance with rapid ventricular pacing. This new technology is a promising alternative for selected elderly high-risk patients and seems to be associated with good outcome and a minimal stroke risk.
Keywords: Aortic stenosis; Aortic valve; Minimally invasive; Transapical; Transcatheter Introduction Conventional aortic valve replacement (AVR) has evolved to a highly standardized technique resulting in excellent outcome (Table 1) w1–7x. However, due to the aging population, an increasing number of octogenarians now require surgical therapy for severe symptomatic aortic stenosis (AS). Patients with older age plus additional risk factors as indicated by high logistic EuroSCORE or STS-Score values may not be referred for conventional AVR w8, 9x despite a grave prognosis without intervention w10x. For this subgroup of high-risk patients a less invasive technique to treat AS might be beneficial.
with AS w11x. After initial enthusiasm it became quickly evident that this technique is associated with modest and short-lived clinical improvements only w12x. Thus, the technique of isolated BAV for high-risk patients was widely abandoned. The most disappointing problem of BAV, the recurrence of AS, was overcome by the development of valved-stents (Photo 1: Edwards SAPIEN prosthesis, Photo 2: Medtronic CoreValve prosthesis). In April 2002, the first transcatheter valve was implanted successfully in a high-risk patient with AS. At present three approaches are used to deliver these valvedstents: antegrade transapical, retrograde transfemoral and retrograde transsubclavian.
History During the mid-1980s balloon aortic valvuloplasty (BAV) was advocated for selected high-risk patients * Corresponding author. Universita¨t Leipzig, Herzzentrum, Klinik fu¨r Herzchirurgie, Stru¨mpellstr. 39, 04289 Leipzig, Germany. Tel.: q49 341 865 1424; fax: q49 341 865 1452. E-mail: [email protected] 2010 European Association for Cardio-thoracic Surgery
Surgical technique The optimal environment for transcatheter aortic valve implantation (TAVI) is a hybrid-OR (Photo 3) facilitating high-quality imaging (fixed fluoroscopy system) and providing all surgical equipment for a potential conversion to standard surgical techniques. 1
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939 Table 1. Outcome of octogenarians after conventional AVR w1–7x Author
Journal
City
n
Age
30-day mortality (%)
Roberts et al. w1x Melby et al. w2x Kolh et al. w3x Urso et al. w4x de Vincentiis et al. w5x Filsoufi et al. w6x Leontyev et al. w7x
Am J Cardiol 2007 Ann Thorac Surg 2007 Eur J Cardiothorac Surg 2007 J Heart Valve Dis 2007 Ann Thorac Surg 2008 J Am Geriatr Soc 2008 Ann Thorac Surg 2009
Dallas St. Louis Liege San Sebastian Milan New York Leipzig
196 245 220 100 345 231 282
83.0 83.6 82.8 82.1 82.0 83.0 82.0
10.0 9.0 9.0 8.0 7.5 5.2 9.2
Photo 1. SAPIEN valve: bovine pericardium (ThermaFix) within a balloon-expandable steel-stent.
Delineation of the aortic root geometry is essential before performing transapical aortic valve implantation (TA-AVI). Transesophageal echocardiography (TEE) is the most reliable tool to measure the diameter of the aortic annulus (Video 1, Photo 4) and to assess the pattern of native valve calcification (Video 2). Photo 2. CoreValve device: porcine pericardium within a selfexpanding nitinol frame.
In addition to preoperative TEE we usually perform a cardiac-CT (Photo 5) and an angio-CT (Video 3). The strength of the cardiac-CT is the ability to measure the distance between the left (Photo 6) and right coronary ostia (Photo 7) and the aortic annulus.
placed into the femoral vessel acting as a ‘safety-net’ (Video 4).
TA-AVI is usually performed under general anesthesia (short acting drugs) and guided by TEE and fluoroscopy. Prior to skin incision a percutaneous venous wire and a 6 F arterial sheath (that is needed anyhow for later root angiography over a pigtail catheter) are
A left anterolateral minithoracotomy is placed in the fifth or possibly sixth intercostal space (Schematic 1). After rib spreading some epicardial fatty tissue is excised and the pericardium is opened longitudinally. Then an epicardial pacing lead and the purse-strings
2
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
Video 2. TEE: short-axis view to assess the calcification pattern. Concentric calcification is ideal for TAVI whereas a fixed commissure may lead to a paravalvular leak.
Photo 3. Hybrid-OR at the Heartcenter University of Leipzig combining a high-quality fixed fluoroscopy system (as it is used in cathlabs) with sterility requirements and surgical equipment including a ‘pump’ on standby of a regular cardiac surgical OR.
Video 1. TEE: long-axis view demonstrating the anatomy of the LVOT and the aortic root and a mild mitral regurgitation.
(Prolene 2-0 with MH needle) are placed where care is needed to avoid the fatty tissue at the true apex (optimal area lies more to the antero-lateral aspect) and to take sufficiently deep bites (Video 5).
Photo 5. Cardiac-CT demonstrating the anatomy of the aortic root including the diameters of the aortic annulus, the bulbus and the sinutubular junction.
In the next step, angulation of the C-arm needs to be set in order to obtain a perpendicular view onto the aortic annulus (Video 6).
Video 3. Angio-CT: 3D-reconstruction of the aorta and the iliac arteries.
After the valve has been prepared (Video 7) the apex is punctured and a soft guidewire is placed into the ascending aorta (Schematic 2). Now a 14 F soft sheath is advanced over the stenotic aortic valve and a superstiff guidewire is anchored into the descending aorta (Video 8). Prior to sheath insertion TEE should exclude any interference of the wire with the mitral valve (Video 9).
Photo 4. Measurement of the diameter of the aortic annulus: including all cusp calcifications, at mid-systole from the insertion of the right coronary cusp at the junction between interventricular septum, aortic annulus and aortic root and the insertion of the left coronary cusp just opposite at the junction between the anterior mitral leaflet, aortic annulus and aortic root.
In the next step, balloon-valvuloplasty (Schematic 3, Video 10) is performed under rapid ventricular pacing (RVP) to temporarily reduce cardiac output. Now the 26 F-sheath is bluntly inserted, the dilator is retrieved and the valve delivery system is attached, and after carefully de-airing the system the prosthesis 3
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
Photo 6. Cardiac-CT: distance between the left coronary ostia and the aortic annulus.
Photo 7. Cardiac-CT: distance between the right coronary ostia and the aortic annulus.
is advanced to the level of the aortic annulus (Schematic 4, Video 11). By manipulating the stiff wire (slack/tension) the tilting of the valve within the aortic annulus is adjusted to obtain a coaxial position (Video 12). After carefully positioning the valve (target: one-third to one-half above the annulus) the prosthesis is deployed by active ballooning under RVP (Schematic 5, Video 13). After implantation the valve function is assed by angio (Video 14) and TEE (Video 15). Finally, the delivery system is retrieved and the apex is secured by the purse-strings (Video 16).
Results After the initial pioneering phase of TAVI results have now stabilized. Due to the lack of a sufficient scoring 4
Video 4. ‘Safety-net’. A percutaneous femoral wire is advanced into the right atrium under fluoroscopic or TEE guidance. In addition, a 6 F arterial sheath is placed into the femoral artery. The access side should be chosen according to potential calcifications or kinking seen on the angio-CT. This vascular access allows for rapid percutaneous cannulation in Seldinger technique and facilitates immediate conversion to the cardiopulmonary bypass if required.
system, results of different groups using different approaches and devices are hardly comparable. Furthermore, although not supported by any scientific data, most groups follow a ‘transfemoral first’ strategy that naturally leads to a higher risk profile in the trans-
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
Video 7. Preparation of the Edwards SAPIEN valve: crimping of the valve onto the delivery balloon, attachment of the pusher and the loader.
Schematic 1. Transapical access. An incision in the fifth or sixth intercostal space usually results in a good exposure of the left ventricular apex. In patients with small ventricles the incision should be placed in the mid-clavicular line, in case of enlarged ventricles more to the lateral aspect.
Video 5. Anterolateral minithoracotomy. Four pericardial staysutures allow for bilateral lung ventilation and enhance the exposure of the apex. Two purse-strings are placed using Prolene 2-0 with a large MH needle reinforced with five Teflon pledgets. Schematic 2. After apical puncture (into the direction of the patient’s right shoulder) a soft guidewire is advanced in an antegrade fashion across the stenotic aortic valve.
Video 6. Root angiography to check for a correct angulation of the fluoroscopic system (approximately LAO/cranial 108/108). All three valve cusps should be in one plane, the commissure between the left and right coronary cusp in the middle and the takeoff of the left coronary artery clearly visible.
apical group that has to be taken into account when comparing the results in regard to the access site. In accordance to the recommendations published by ESC and EACTS recently, patients are eligible for TAVI
Video 8. Using Seldinger technique a 14 F soft-tip sheath is advanced into the ascending aorta. Then, with the help of a right Judkins catheter, the superstiff guidewire is placed into the descending aorta with minimal manipulation around the aortic arch only.
in our institution if they are at higher age ()75 years) and presenting with additional risk factors: • STS-Score )10% or logEuroSCORE -20% • Re-do cases with patent LIMA to LAD 5
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
Video 9. TEE 3D-probe in X-plane mode confirming correct position of the guidewire in short-axis and simultaneously long-axis view.
Schematic 4. SAPIEN prosthesis within the aortic annulus.
Schematic 3. Balloon-valvuloplasty using a 20 mm balloon.
Video 11. Insertion of the 26 F-sheath and delivery of the valve to the aortic annulus.
Video 10. Balloon-valvuloplasty under rapid ventricular pacing (RVP: 180 beats/min).
• Porcelain aorta • History of chest radiation or mediastinitis • Degenerated aortic bioprosthesis (valve-in-a-valve) • Other factors (liver failure, severe immobility, hematological-, coagulation-disorders) At our center we do not believe in a ‘transfemoral first’ approach. Thus, all patients are individually discussed in an interdisciplinary team conference. Then optimal 6
Video 12. Tilting of the valve within the aortic annulus.
treatment strategy is selected for each individual patient. Nevertheless, there are factors to favor either one or the other approach. Transfemoral AVI without general anesthesia might be beneficial for patients presenting with severe respiratory dysfunction. On the other hand, in patients with small femoral vessels,
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
Video 14. Final result on angio: patent coronaries and a competent valve.
Video 15. TEE excluding any significant transvalvular or paravalvular leak.
Schematic 5. Valve implantation by active balloon inflation.
severe kinking or generally heavily calcified vessels, the transapical approach avoids potential vascular complications. At the time of writing, our personal experience included more than 200 high-risk elderly patients who underwent TA-AVI. Mean age was above 80 years with a mean STS-Score of 12"7% and a mean logEuroSCORE of 32"16%. All patients received an Edwards SAPIEN valve following an oversizing concept of at least 2 mm. Table 2 summarizes the outcome and the rate of perioperative complications.
Video 13. Valve deployment after a final angio control under RVP. A slow or stepwise balloon inflation allows for final adjustments if necessary.
Video 16. Retrieval of the delivery system, tying of the purse-strings and closure of the incision. Table 2. Outcome after TA-AVI (Leipzig results) Total ns240 30-day mortality Stroke Conversion to sternotomy Coronary problem Too low valve position Annular tear Valve embolization Rethoracotomy (bleeding) New onset of chronic dialysis Pacemaker implantation Wound infection Postoperative echo parameters: AV Pmean Mean regurgitation AV (grade) None (trace) 18 28
9.6% 1% 2% 2% 1% 1% – 2% 2% 4% 1% 6"3 (mmHg) 0.5"0.6 135 (56%) 90 (38%) 15 (6%)
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J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939 Table 3. Potential complications and ‘bail-out’ options Event
Possible solution
Valve deployed too low Valve deployed too high/coronary occlusion
Second valve-in-a-valve with a slightly higher position 1) If a guidewire can be placed, consider stent-implantation 2) If not, sternotomy and surgical bypass grafts beating-heart on-pump Re-ballooning might help 1) If one leaflet is not moving try mobilization by pigtail manipulation, wait until arterial pressure has fully recovered 2) If not successful consider second valve-in-valve implantation eventually slightly higher to avoid interference of the native aortic valve cusps 1) Low-dose epinephrine into the aortic root over the pigtail is often helpful 2) In case of persistent low-output convert to CPB using the ‘safety-net’ for reperfusion. Bridge with chest compressions.
Paravalvular leak ()grade 1q) Central leak ()grade 1q)
Hemodynamical instability
Potential intraoperative complications and ‘bail-out’ options Given the high-risk nature of this special patient subgroup any complication might occur anytime. To maximise patient safety, the procedure should be performed in a fully equipped hybrid-OR allowing for conversion to conventional surgery including all standard techniques. Placement of a femoral ‘safety-net’ w13x prior to skin incision ensures timely pump-support if required. In addition to all ‘hardware’ precautions, a good team coordination and communication is most important to professionally deal with any potential complications. Table 3 demonstrates typical intraoperative complications and ‘bail-out’ options.
Discussion TA-AVI has evolved as a standard and routine procedure to treat elderly patients with AS using a minimally invasive approach. Most groups advocate the percutaneous retrograde transfemoral approach as the first choice if feasible. At first glance this seems reasonable as this access is the least invasive but the rate of major vascular complications associated with a transfemoral technique is still substantial (;10%) and the complication rate associated with the apical approach in our experience is acceptably low (;1%). In addition, exact valve positioning is far more complicated when using a retrograde approach and seems to be associated with more manipulations around the (calcified) aortic arch. Hence, this might translate into a higher stroke rate. To date, there is no scientific evidence proving the superiority of one or the other of these approaches. Although current outcome of TAVI is acceptable given the risk profile of this high-risk subgroup of patients, we still lack a prospectively randomized trial proving 8
superiority of this new technique compared with the excellent outcome of conventional AVR. Thus, TAVI should be restricted to selected high-risk patients until there are more hard clinical data available.
Conclusion TA-AVI is an off-pump and minimally invasive procedure that has evolved to a promising alternative in selected elderly high-risk patients. The technique is feasible even in the presence of severe peripheral vascular disease, requires limited surgical trauma only and allows for exact antegrade valve positioning.
References w1x Roberts WC, Ko JM, Garner WL, Filardo G, Henry AC, Hebeler RF Jr, Matter GJ, Hamman BL. Valve structure and survival in octogenarians having aortic valve replacement for aortic stenosis (q/aortic regurgitation) with versus without coronary artery bypass grafting at a single US medical center (1993 to 2005). Am J Cardiol 2007;100: 489–495. w2x Melby SJ, Zierer A, Kaiser SP, Guthrie TJ, Keune JD, Schuessler RB, Pasque MK, Lawton JS, Moazami N, Moon MR, Damiano RJ. Aortic valve replacement in octogenarians: risk factors for early and late mortality. Ann Thorac Surg 2007; 83:1651–1656; discussion 1656–1657. w3x Kolh P, Kerzmann A, Honore C, Comte L, Limet R. Aortic valve surgery in octogenarians: predictive factors for operative and long-term results. Eur J Cardiothorac Surg 2007;31:600–606. w4x Urso S, Sadaba R, Greco E, Pulitani I, Alvarez L, Juaristi A, Goiti JJ. One hundred aortic valve replacements in octogenarians: outcomes and risk factors for early mortality. J Heart Valve Dis 2007;16:139–144. w5x de Vincentiis C, Kunkl AB, Trimarchi S,
J. Kempfert et al. / Multimedia Manual of Cardiothoracic Surgery / doi:10.1510/mmcts.2009.003939
w6x
w7x
w8x
w9x
Gagliardotto P, Frigiola A, Menicanti L, Di Donato M. Aortic valve replacement in octogenarians: is biologic valve the unique solution? Ann Thorac Surg 2008;85:1296–1301. Filsoufi F, Rahmanian PB, Castillo JG, Chikwe J, Silvay G, Adams DH. Excellent early and late outcomes of aortic valve replacement in people aged 80 and older. J Am Geriatr Soc 2008;56: 255–261. Leontyev S, Walther T, Borger MA, Lehmann S, Funkat AK, Rastan A, Kempfert J, Falk V, Mohr FW. Aortic valve replacement in octogenarians: utility of risk stratification with EuroSCORE. Ann Thorac Surg 2009;87:1440–1445. Iung B, Cachier A, Baron G, Messika-Zeitoun D, Delahaye F, Tornos P, Gohlke-Barwolf C, Boersma E, Ravaud P, Vahanian A. Decision-making in elderly patients with severe aortic stenosis: why are so many denied surgery? Eur Heart J 2005; 26:2714–2720. Pai RG, Kapoor N, Bansal RC, Varadarajan P.
w10x
w11x
w12x
w13x
Malignant natural history of asymptomatic severe aortic stenosis: benefit of aortic valve replacement. Ann Thorac Surg 2006;82:2116–2122. Varadarajan P, Kapoor N, Bansal RC, Pai RG. Clinical profile and natural history of 453 nonsurgically managed patients with severe aortic stenosis. Ann Thorac Surg 2006;82:2111–2115. Cribier A, Savin T, Saoudi N, Rocha P, Berland J, Letac B. Percutaneous transluminal valvuloplasty of acquired aortic stenosis in elderly patients: an alternative to valve replacement? Lancet 1986;1: 63–67. Bashore TM, Davidson CJ. Follow-up recatheterization after balloon aortic valvuloplasty. Mansfield Scientific Aortic Valvuloplasty Registry Investigators. J Am Coll Cardiol 1991;17:1188–1195. Kempfert J, Walther T, Borger MA, Lehmann S, Blumenstein J, Fassl J, Schuler G, Mohr FW. Minimally invasive off-pump aortic valve implantation: the surgical safety net. Ann Thorac Surg 2008;86:1665–1668.
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