Medical Care |

Medical Care



Chaque forme pharmaceutique présente ses propres avantages et inconvénients acheter du diflucan.

mais n'ont pas d'effets néfastes pour l'organisme dans son ensemble.

Percutaneous aortic valve replacement: overview and suggestions for anesthestic management

Journal of Clinical Anesthesia (2010) 22, 373–378 Percutaneous aortic valve replacement: overview andsuggestions for anesthestic management☆ Hermann Heinze MD (Assistant Professor)a,⁎, Holger Sier MD, (Staff Cardiac Surgeon)b,Ulrich Schäfer MD (Senior Cardiologist)c, Matthias Heringlake MD, PhD (Professor)a aDepartment of Anesthesiology, University of Lübeck, 23538 Lübeck, GermanybDepartment of Cardiothoracic Surgery, University of Lübeck, 23538 Lübeck, GermanycDepartment of Cardiology, Asklepios Klinik St. Georg, 20099 Hamburg, Germany Received 29 December 2008; revised 22 April 2010; accepted 16 May 2010 Abstract Transcutaneous aortic valve replacement (AVR) is increasingly used for high-risk patients with severe aortic stenosis, who have high operative mortality for surgical placement during cardiopulmonary bypass (CPB). Retrograde transfemoral AVR is usually performed during sedation, Aortic valve replacement; whereas antegrade transapical AVR is done with general anesthesia. Both procedures can be carried out without CPB. Extended hemodynamic monitoring, including pulmonary artery catheterization and Atrioventricular block transesophageal echocardiography, may be useful. Transfemoral AVR requires placement of atransvenous right ventricular pacing lead. Typical complications include local bleeding, obstruction ofthe coronary ostia, and neurological insult due to embolization of sclerotic material. Aortic regurgitationdue to paravalvular leakage or inadequate device expansion also may occur. Renal function maydeteriorate on excessive application of contrast medium. Atrioventricular blocks may occur later ratherthan after conventional AVR which tend to occur immediately.
2010 Elsevier Inc. All rights reserved.
stenosis increasingly are elderly with significant comorbid-ities. As a result, AVR using conventional open-heart Aortic valve replacement (AVR) is the treatment of surgery with median sternotomy and cardiopulmonary choice for patients with severe degenerative aortic stenosis, bypass (CPB) may be associated with unacceptably high offering both symptomatic relief and a potential for mortality and morbidity in certain patients.
improved long-term survival. Patients presenting with aortic Although most patients are treated for symptomatic and critical aortic stenosis, less invasive procedures would bebeneficial. Intervention could be extended to patients for whom the risk of surgical intervention is currently Financial disclosure: Dr. U. Schäfer does consulting work and receives honoraria from CRS™, CoreValve Inc, Irvine, CA, USA. Dr.
prohibitive . Possible steps to minimize perioperative M. Heringlake receives scientific support and honoraria from Edwards risk are to avoid sternotomy, CPB, and mechanical Lifescience, Irvine, CA, USA and Covidien Healthcare, Mansfield, ventilation. Therefore, alternative modes of valve replace- ment strategies have been developed. After studies in ⁎ Corresponding author. Tel.: +49 (0) 451 500 4057; fax: +49 (0)451 animals in 2002 Cribier et al. were the first to implant E-mail address: (H. Heinze).
a transcutaneous, catheter-mounted aortic valve using the 0952-8180/$ – see front matter 2010 Elsevier Inc. All rights reserved.
H. Heinze et al.
Mortality and morbidity rates reported for octogenarians undergoing isolated conventional transfemoral or transapical aortic valve replacement (AVR) Conventional isolated AVR (For more information on the cause of the mortality and morbidity, the reader is referred to the specific literature.)MACE = Perioperative major adverse cardiovascular and cerebral events, including death from any cause, major arrhythmia, myocardial infarction,cardiac tamponade, stroke, urgent or emergent conversion to surgery, emergent percutaneous coronary intervention, cardiogenic shock, endocarditis, oraortic dissection.
antegrade transfemoral venous route . This approach is AVR. Excellent results have been achieved with conven- very challenging ; the retrograde arterial approach tional isolated AVR in the last few years, with operative then was introduced (ie, transfemoral-AVR and transa- mortality rates of 5% to 10% noted in octogenarians pical AVR ).
Mortality risk may increase excessively in the presence of Initial results show at least comparable mid-term additional factors. A strong link between operative mortality morbidity and mortality rates to those with conventional and the following predictive factors has been seen : isolated AVR Accordingly, as numbers advanced heart failure with severe left ventricular (LV) increase , cardiac anesthesiologists will be confronted dysfunction; comorbidities, eg, respiratory dysfunction, with this patient group with increasing frequency. For renal dysfunction, and peripheral or coronary arterial both procedures, no CPB per se is needed; one may atherosclerosis; and need for urgent surgery.
speculate that in the near future anesthesiologists with no Beside "technical" inclusion criteria such as certain aortic experience in cardiac anesthesia may be caring for annulus and ascending aorta diameter a combina- these patients.
tion of risk factors or scoring systems also have been usedas inclusion criteria. There are no published guidelines forpatient selection, and percutaneous AVR remains investiga- 2. Technical aspects tional . Therefore, patients presenting for percutaneousTF-AVR or TA-AVR are high-risk patients with highoperative mortality, and usually they have been refused for Transcatheter AVR, especially transapical AVR, requires standard AVR.
a special operating room (OR). The so-called "hybrid OR" Exclusion criteria include sepsis or acute endocarditis; is a standard OR with an additional fluoroscopic excessive femoral, iliac, or aortic atherosclerosis; calcifica- angiography system equal to any standard catheterization tion or tortuosity (for transfemoral AVR); aortic aneurysm; laboratory. It combines all aspects of sterility needed for bleeding diathesis or coagulopathy; recent myocardial conventional surgery with the imaging techniques of a infarction (MI) or cerebrovascular accident; mitral or catheterization laboratory. Exellent imaging is required for tricuspid valvular insufficiency (N grade II); LV or atrial exact positioning of the valve. In the event of emergency thrombus; uncontrolled atrial fibrillation; and previous aortic conversion to conventional surgery, CPB should be readily valve replacement. In addition, patients with echocardio- available. Transfemoral AVR procedures are typically graphic aortic valve annulus diameter b 20 mm or N 27 mm performed in the catheterization laboratory. In the majority and ascending aorta diameter N 45 mm were excluded of cases, the anesthesiologist is confronted with limited space . Some of these contraindications have been in an unfamiliar surrounding.
abandoned For example, after evalution of thefeasibility of transapical valve-in-a-valve implantation inanimals , the first human case was reported There is ongoing discussion as to whether certain valve malforma-tions such as biscupid aortic stenosis could be an exclusion Aortic stenosis is the most common valvular heart disease criterion, as stent deployment may be impaired .
and its prevalence is increasing with age . Approximately During preoperative assessment, the anesthesiologist 2% to 5% of elderly individuals aged N75 years present with should be especially aware of signs of severly reduced signs of severe aortic stenosis and are scheduled for elective LV systolic function, pulmonary arterial (PA) hypertension, Anesthesia for percutaneous aortic valve replacement respiratory dysfunction, especially chronic obstructive 6. Transfemoral aortic valve replacement pulmonary disease, renal dysfunction or failure, and historyof neurological insult. In addition, many patients have In the beginning, transfemoral AVR was commonly had previous cardiac surgery and may be at increased risk performed during general anesthesia . Since no CPB is of bleeding.
required, deep sedation is sufficient A combinationof propofol (0.3-1.5 to 3 mg/kg/hr) and remifentanil (1 to6 μg/kg/hr) works well. Currently there are no data available comparing general anesthesia and deep sedation. Anindividualized approach is recommended.
Beside standard monitoring, invasive arterial and central Premedication consists of aspirin, clopidogrel, and venous blood pressures, no clear recommendations for antibiotics for procedural prophylaxis. Aspirin (100 mg) hemodynamic monitoring have been published. A PA and clopidogrel (75 mg) are recommended for 6 months, catheter for measuring PA pressure and mixed venous with lifelong aspirin (100-300 mg) Placement of an oxygen saturation may be used to detect ventricular intravenous (IV) right ventricular pacing lead is mandatory dysfunction and provide valuable data on global oxygen and functionality should be tested before the procedure. A balance As with conventional AVR, the decision to transthoracic pacemaker is not recommended. Two methods insert a PA catheter should be based on the comorbidities of of transfemoral AVR have been published, but as antegrade the individual patient.
transfemoral venous access carries the risk of injury to the Transesophageal echocardiography (TEE) is extremely mitral valve, retrograde transfemoral AVR is used nearly helpful in determining acute changes in myocardial perfor- exclusively. Vascular access is obtained either with or mance during the procedure, to determine the position without standard surgical cut-down of the subclavian artery, and correct function of the prosthetic valve, and – most external iliac artery, or common femoral artery. A stiff important – to rule out residual aortic regurgitation and guidewire is placed in retrograde fashion into the LV. Using paravalvular leakages During transapical AVR per- fluoroscopic guidance and rapid pacing (150-200 bpm) to formed with general anesthesia, TEE should be included minimize ventricular outflow, balloon dilatation of the . Unfortunately, in patients undergoing transfemoral stenotic valve is performed. After the balloon catheter is AVR without general anesthesia, use of TEE during the withdrawn again, the device is advanced and positioned procedure is limited. In cases where TEE may not be used, within the native valve. The CoreValve revalving system is a intraoperative and postoperative transthoracic echocardiog- self-expanding device and needs only additional balloon raphy may help determine the etiology of hemodynamic dilatation for modelling into the aortic root, while the instability. As there is no access to the ascending aorta for Edwards-Sapien valve has to be expanded actively during epicardial echocardiography during both procedures, this rapid pacing. After expansion correct positioning and technique, which is helpful during conventional aortic function is verified with fluoroscopic angiography and/or surgery cannot be used as an alternative.
7. Transapical aortic valve replacement(TA-AVR) Currently, more than 30 companies work in the development of stent-fixed valves. Two devices have been The TA-AVR is performed during general anesthesia.
introduced into clinical practice for sutureless transcatheter Initially one-lung ventilation was instituted using a double- AVR, ie, the CoreValve Revalving System (CRS™; lumen tube, but this approach has been abandoned. A left CoreValve, Inc., Irvine, CA, USA) and the Edwards-Sapien anterolateral intercostal incision is used to expose the LV valve (Edwards Lifesciences, Inc., Irvine, CA, USA).
apex and the pericardium is incised and retained. In The CoreValve aortic valve prosthesis consists of a addition, temporary epicardial ventricular pacing wires are trileaflet bioprosthetic porcine pericardial tissue valve placed. With the heart continuously beating, the apex is mounted and sutured in a self-expanding nitinol stent.
punctured and the aortic valve passed in antegrade fashion Nitinol, a nickel-titanium alloy, is a shape memory metal.
using a soft guidewire. A superstiff guidewire is inserted The balloon expandable Edwards-Sapien valve is con- and positioned across the aortic arch and anchored in the structed from a tubular slotted stainless steel stent with an descending aorta. A balloon valvuloplasty catheter is attached bovine pericardial trileaflet valve.
positioned using fluoroscopic and/or TEE guidance. A Both valves have received CE mark approval (consumer valvuloplasty is performed to optimize the valve area safety certification of the European Union) for transfemoral for device placement. The balloon catheter is withdrawn implantation, while for the transapical approach only the and a 33-French transapical delivery sheath is inserted Edwards Sapien valve has been approved.
followed by the valve. After de-airing and proper

H. Heinze et al.
A. Schematic drawing of the transfemoral and transapical approach for aortic valve replacement and retrograde positioning of the catheter-mounted valve. B. Dilatation of the device dilatation with a balloon. C. Correct positioning at the end of the procedure. D. Devicepositioning and dilatation using an antegrade transapical approach with an introducer through the left ventricular apex. (Reproduced withpermission of Edwards Lifesciences, Inc., Irvine, CA, USA).
positioning, the valve is implanted during ventricular rapid positioning and function have been verified, the myocar- pacing (D). Sometimes repeated dilatations are dium is closed using sutures placed at the outset and the necessary to minimize paravalvular leakage. After correct thorax is closed.
Anesthesia for percutaneous aortic valve replacement Fluoroscopy time is usually less than 20 minutes, with AVR may increase bleeding problems and may be life- procedure time around 180 minutes .
threatening in the event that conversion to conventional on- The transapical technique is considered safer in patients pump AVR is indicated.
with severe peripheral vascular disease or increased risk of Postprocedural care in patients after TF-AVR or TA-AVR stroke as fewer aortic manipulations are necessary.
differs from care given after conventional surgical AVR.
During both procedures, the anesthesiologist monitors While postoperative patients undergoing AVR with CPB are hemodynamics, especially during balloon valvuloplasty and often hypovolemic and show a typical post-CPB inflamma- device deployment, as they might not recover immediately tory response with decreased systemic vascular resistance, after cessation of rapid pacing. New or increased aortic leading to the need for relatively high amounts of fluids and regurgitation might complicate the situation. In addition, vasopressor therapy, patients after percutaneous AVR are at ventricular fibrillation is possible and immediate electrical risk of hypervolemia, especially if residual aortic regurgita- defibrillation and cardiopulmonary resuscitation is necessary.
tion is present. Thus, adequate hemodynamic monitoring anddetailed hemodynamic care is necessary. Special attention torenal function is required, especially in patients with 8. Perioperative and postprocedural care preoperatively reduced kidney function, as the nephrotoxiceffects of the contrast medium may aggravate the situation.
More than 1,200 transfemoral AVR for both CoreValve For patients at risk, preventive strategies to reduce the and Edwards-Sapien valves and about 450 transapical AVR likelihood of contrast medium-induced nephropathy include have been performed. As greater numbers of patients are preprocedural and periprocedural IV hydration therapy and treated, the number of complications presumably will use of the lowest dose possible of low-osmolarity contrast decrease. The physician responsible for periprocedural care medium. The use of nephroprotective agents such as N- should be aware of certain risks.
acetylcysteine or theophylline is controversial, but may be During implantation, embolization of atherosclerotic considered in certain patients Loop diuretics plaques is possible due to pre-dilation and detachment or increase renal injury after application of radiocontrast dye fragmentation. Migration of the valve stent into the these drugs should be used cautiously.
ascending aorta or the aortic arch is possible, with the need Atrioventricular conduction blocks are a well-known of conversion to standard surgery. Studies have reported a complication of aortic valve surgery. It is noteworthy that mortality rate of up to 15%, stroke at 0.4% to 4.6%, MI at after transfemoral AVR and transapical AVR, blocks may 0.2% to 6.5%, and cardiac perforation at 0.3% to 1.8% after develop up to one week post-procedure, necessitating balloon valvuloplasty . Published short-term and mid- permanent pacemaker insertion .
term results of percutaneous AVR and isolated conventionalAVR are summarized in .
During antegrade transfemoral AVR, where a transseptal puncture is performed and the mitral valve is crossed using aballoon flotation catheter, there is a risk of tethering or trauma-tizing the anterior leaflet of the mitral valve. This situation Transcutaneous AVR, whether using the transfemoral or may lead to acute severe mitral regurgitation . The retro- the transapical route, is an innovative approach. Anesthe- grade approach avoids potential mitral leaflet complications.
siologists caring for these patients either during or after the A severe complication shared by all three approaches is procedure should have sound knowledge of the procedure the obstruction of the coronary ostia with subsequent MI and its risks and complications. As different specialties and A special problem may be aortic regurgitation due to personnel, including cardiac surgeons, cardiologists, paravalvular leakages or inadequate device expansion.
anesthesiologists, OR nurses, and technicians have to work Minor regurgitation immediately after insertion of the together in unfamiliar surroundings, cooperation, collabora- valve may be acceptable in patients with preserved tion, and experience are of paramount interest for success.
ventricular function and it typically disappears after several Before transcutaneous AVR may be recommended for a hours. Moderate and high-grade regurgitation normally is wider patient group, properly designed, prospective, ran- treated with additional device dilatation. In case of severely domized clinical trials comparing transfemoral AVR, depressed LV function, TEE may underestimate the true transapical AVR, and conventional surgical AVR are severity of the situation and special emphasis regarding necessary to determine long-term outcome.
systemic cardiopulmonary function is essential to rule outacute heart failure.
During transapical AVR, there is a constant risk of systemic air embolism with catastrophic clinical conse-quences. Local bleeding problems at the catheter insertion [1] Stuge O, Liddicoat J. Emerging opportunities for cardiac surgeons site may require surgical repair. Anticoagulant loading within structural heart disease. J Thorac Cardiovasc Surg 2006;132: therapy with clopidogrel and aspirin during transfemoral H. Heinze et al.
[2] Andersen HR, Knudsen LL, Hasenkam JM. Transluminal implantation [15] Walther T, Kempfert J, Borger MA, et al. Human minimally invasive of artificial heart valves. Description of a new expandable aortic valve off-pump valve-in-a-valve implantation. Ann Thorac Surg 2008;85: and initial results with implantation by catheter technique in closed chest pigs. Eur Heart J 1992;13:704-8.
[16] Zegdi R, Sleilaty G, Lafont A, Fabiani JN. Percutaneous aortic valve [3] Bonhoeffer P, Boudjemline Y, Saliba Z, et al. Transcatheter replacement with the CoreValve prosthesis [Letter]. J Am Coll Cardiol implantation of a bovine valve in pulmonary position: a lamb study.
[17] Heringlake M, Heinze H, Misfeld M, Klaus S, Bechtel M. Goal- [4] Cribier A, Eltchaninoff H, Bash A, et al. Percutaneous transcatheter directed hemodynamic optimization in high-risk cardiac surgery implantation of an aortic valve prosthesis for calcific aortic stenosis: patients: a tale from the past or a future obligation? Minerva Anestesiol first human case description. Circulation 2002;106:3006-8.
[5] Cribier A, Eltchaninoff H, Tron C, et al. Treatment of calcific aortic [18] Eltzschig HK, Rosenberger P, Löffler M, Fox JA, Aranki SF, Shernan stenosis with the percutaneous heart valve: mid-term follow-up from SK. Impact of intraoperative transesophageal echocardiography on the initial feasibility studies: the French experience. J Am Coll Cardiol surgical decisions in 12,566 patients undergoing cardiac surgery. Ann Thorac Surg 2008;85:845-52.
[6] Grube E, Schuler G, Buellesfeld L, et al. Percutaneous aortic valve [19] Fassl J, Walther T, Birnbaum J, Mohr FW, Ender J. Transesophageal replacement for severe aortic stenosis in high-risk patients using the echocardiographic monitoring during transapical aortic valve implan- second-and current third-generation self-expanding CoreValve pros- tation. Appl Cardiopulm Pathophysiol 2006;10:27-31.
thesis: device success and 30-day clinical outcome. J Am Coll Cardiol [20] Hilberath JN, Shernan SK, Segal S, Smith B, Eltzschig HK. The feasibility of epicardial echocardiography for measuring aortic valve [7] Lichtenstein SV, Cheung A, Ye J, et al. Transapical transcatheter aortic area by the continuity equation. Anesth Analg 2009;108:17-22.
valve implantation in humans: initial clinical experience. Circulation [21] Rosenberger P, Shernan SK, Löffler M, et al. The influence of epiaortic ultrasonography on intraoperative surgical management in [8] Walther T, Chu MW, Mohr FW. Transcatheter aortic valve 6051 cardiac surgical patients. Ann Thorac Surg 2008;85:548-53.
implantation: time to expand? Curr Opin Cardiol 2008;23:111-6.
[22] Figulla HR, Cremer J, Walther T, et al. Position paper on catheter- [9] Iung B. Management of the elderly patient with aortic stenosis. Heart based aortic valve surgery. Der Kardiologe 2009;3:199-206.
[23] Sauren B, Zickmann B, Gerckens U, Grube E, Felderhoff T, Iversen S.
[10] Kolh P, Kerzmann A, Honore C, Comte L, Limet R. Aortic valve TOE support for percutaneous transluminal implantation of a self- surgery in octogenarians: predictive factors for operative and long- expanding valve prothesis for interventional treatment of aortic valve term results. Eur J Cardiothorac Surg 2007;31:600-6.
stenosis. Appl Cardiopulm Pathophysiol 2006;10:24-6.
[11] Grube E, Laborde JC, Gerckens U, et al. Percutaneous implantation of [24] Zierer A, Wimmer-Greinecker G, Martens S, Moritz A, Doss M. The the CoreValve self-expanding valve prosthesis in high-risk patients transapical approach for aortic valve implantation. J Thorac Cardio- with aortic valve disease: the Siegburg first-in-man study. Circulation vasc Surg 2008;136:948-53.
[25] Lieberman EB, Bashore TM, Hermiller JB, et al. Balloon aortic [12] Walther T, Falk V, Kempfert J, et al. Transapical minimally invasive valvuloplasty in adults: failure of procedure to improve long-term aortic valve implantation: the initial 50 patients. Eur J Cardiothorac survival. J Am Coll Cardiol 1995;26:1522-8.
Surg 2008;33:983-8.
[26] Hanzel GS, O'Neill WW. Complications of percutaneous aortic valve [13] Rosengart TK, Feldman T, Borger MA, et al; American Heart replacement: experience with the Cribier-Edwards percutaneous heart Association Council on Cardiovascular Surgery and Anesthesia; valve. Eurointervention Suppl 2006;1(Suppl A):A3-8.
American Heart Association Council on Clinical Cardiology; [27] Flecher EM, Curry JW, Joudinaud TM, Kegel CL, Weber PA, Duran Functional Genomics and Translational Biology Interdisciplinary CM. Coronary flow obstruction in percutaneous aortic valve Working Group; Quality of Care and Outcomes Research Interdisci- replacement. An in vitro study. Eur J Cardiothorac Surg 2007;32: plinary Working Group. Percutaneous and minimally invasive valve procedures: a scientific statement from the American Heart Associ- [28] Gonzales DA, Norsworthy KJ, Kern SJ, et al. A meta-analysis of ation Council on Cardiovascular Surgery and Anesthesia, Council on N-acetylcysteine in contrast-induced nephrotoxicity: unsupervised Clinical Cardiology, Functional Genomics and Translational Biology clustering to resolve heterogeneity. BMC Med 2007;5:32.
Interdisciplinary Working Group, and Quality of Care and Outcomes [29] Kelly AM, Dwamena B, Cronin P, Bernstein SJ, Carlos RC. Meta- Research Interdisciplinary Working Group. Circulation 2008;117: analysis: effectiveness of drugs for preventing contrast-induced nephropathy. Ann Intern Med 2008;148:284-94.
[14] Walther T, Falk V, Dewey T, et al. Valve-in-a-valve concept for [30] Solomon R, Werner C, Mann D, D'Elia J, Silva P. Effects of saline, transcatheter minimally invasive repeat xenograft implantation. J Am mannitol, and furosemide to prevent acute decreases in renal function Coll Cardiol 2007;50:56-60.
induced by radiocontrast agents. N Engl J Med 1994;331:1416-20.


Vitamin e supplementation and lifespan in model organisms

Contents lists available at Ageing Research Reviews Vitamin E supplementation and lifespan in model organisms I.M.A. Ernst , K. Pallauf , J.K. Bendall , L. Paulsen , S. Nikolai , P. Huebbe , T. Roeder , G. Rimbach a Institute of Human Nutrition and Food Science, Christian-Albrechts-University Kiel, Hermann-Rodewald-Straße 6-8, D-24118 Kiel, Germany b Zoological Institute, Zoophysiology II, Christian-Albrechts-University Kiel, Olshausenstraße 40, D-24098 Kiel, Germany

Schweizerische Vereinigung für Offizielles Mitteilungsblatt der Schweizerischen Vereinigung für Parapsychologie 7. Jg / Nr. 37 – Juli/August 2007 Parapsychologie, Brückfeldstr. 19, Tel. 031 302 00 33, Fax 031 302 00 50 Ich bin eine Seele Internet: E-Mail: Liebe Leserinnen, liebe Leser, Ich habe einen Körper