ATS
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to Personal Folders
Right arrow Download to citation manager
Right arrow Author home page(s):
Juliane Kilo
Herwig Antretter
Right arrow Permission Requests
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hoefer, D.
Right arrow Articles by Antretter, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hoefer, D.
Right arrow Articles by Antretter, H.
Related Collections
Right arrow Mechanical Circulatory Assistance

Ann Thorac Surg 2006;82:28-33
© 2006 The Society of Thoracic Surgeons

Original article: Cardiovascular

Outcome Evaluation of the Bridge to Bridge Concept in Patients With Cardiogenic Shock

Daniel Hoefer, MD a , * , Elfriede Ruttmann, MD a , Gerhard Poelzl, MD b , Juliane Kilo, MD a , Christoph Hoermann, MD c , Raimund Margreiter, MD d , Guenther Laufer, MD a , Herwig Antretter, MD a

a Department of Cardiac Surgery, Innsbruck Medical University, Innsbruck, Austria
b Department of Cardiology, Innsbruck Medical University, Innsbruck, Austria
c Department of Anesthesiology and Intensive Care Medicine, Innsbruck Medical University, Innsbruck, Austria
d Department of General and Transplantation Surgery, Innsbruck Medical University, Innsbruck, Austria

Accepted for publication February 27, 2006.

* Address correspondence to Dr Hoefer, Department of Cardiac Surgery, Innsbruck Medical University, Anichstrasse 35, A-6020 Innsbruck, Austria; (Email: daniel.hoefer{at}uibk.ac.at).


   Abstract
Top
 Abstract
Introduction
 Patients and Methods
 Results
 Comment
 References
 
BACKGROUND: Patients with cardiogenic shock can be stabilized by percutaneous implantation of extracorporeal membrane oxygenation (ECMO). If weaning from ECMO is impossible, the implantation of a ventricular assist device (VAD) is required. Patients either go for recovery of myocardial function (bridge to recovery) or for heart transplantation (bridge to transplant).

METHODS: One hundred thirty-one patients were supported with ECMO between March 1995 and November 2005. Reasons for ECMO implantation were acute heart failure, acute or chronic heart failure, and postcardiotomy heart failure. In 28 patients, subsequent VAD implantation was necessary (bridge to bridge concept).

RESULTS: Fourteen bridge to bridge patients (50%) became long-time survivors with a mean follow-up of 39 months. Risk factors for mortality were status post–cardiopulmonary resuscitation and elevated lactate and bilirubin levels before VAD implantation. Complications after ECMO and VAD implantation were bleeding and thromboembolic events. The most common cause of death was multiorgan failure.

CONCLUSIONS: Bridge to bridge is a successful concept for selected patients with cardiogenic shock. During ECMO support, patients can be evaluated for comorbidities. For patients with a combination of risk factors (status post–cardiopulmonary resuscitation, elevated lactate levels, and impaired liver function), VAD implantation should be considered very carefully.


   Introduction
Top
 Abstract
 Introduction
Patients and Methods
 Results
 Comment
 References
 
Extracorporeal membrane oxygenation (ECMO) is used for the resuscitation of patients in cardiogenic shock or after cardiopulmonary resuscitation (CPR) [1–6]. Several investigators have demonstrated that patients who present with both postcardiotomy or intrinsic cardiogenic shock can be supported successfully with ECMO [1–6]. Extracorporeal membrane oxygenation offers several advantages: (1) the percutaneous insertion of the cannulas into the femoral vessels is simple and can be performed even during CPR; (2) it provides both cardiac and pulmonary support for hypoxic patients; (3) it avoids a sternotomy incision; (4) it applies to patients in cardiac arrest; (5) it provides time to assess potential transplant candidates; and (6) it is less costly than other forms of mechanical circulatory support [2, 3, 7].

Despite these advantages, ECMO support has several disadvantages that limit its applicability as a long-term support for a bridge to heart transplant: hemolysis, impossibility of patient mobilization, bleeding, stroke, infection, and limited ability to adequately decompress the left ventricle in poorly functioning hearts are the major problems associated with ECMO support. In addition, ECMO increases left ventricular afterload and wall stress [1–4, 8–11].

With the increasingly successful application of long-term implantable ventricular assist devices (VAD), the limitations of ECMO could be overcome by bridging patients to a long-term implantable VAD after initial ECMO resuscitation (bridge to bridge) [1, 2, 7]. In some patients suffering from myocarditis or postcardiotomy cardiogenic shock, weaning from VAD is possible (bridge to recovery). In all other patients, heart transplantation remains the only viable option (bridge to transplant).

The objective of this study is to evaluate the outcome of the bridge to bridge concept and to identify risk factors indicating adverse outcome.


   Patients and Methods
Top
 Abstract
 Introduction
 Patients and Methods
Results
 Comment
 References
 
These data represent a retrospective review of our ECMO and VAD database from 1995 to November 2005. The study was approved by the Institutional Review Board.

One hundred and thirty-one patients were stabilized with ECMO during this period at our center. Etiologies for conservatively intractable cardiogenic shock were acute heart failure (including acute coronary ischemia, myocarditis, and near drowning), acute on chronic heart failure (known ischemic or dilative cardiomyopathy), and postcardiotomy heart failure (inability to wean from cadiopulmonary bypass after cardiac surgery or postoperative acute heart failure; Table 1).


View this table:
[in this window]
[in a new window]
  		Table 1. Demography and Outcome of all ECMO Patients (n = 131)
 
Cannulation was attempted percutaneously in all patients using a modified Seldinger technique. After vessel puncture and guidewire placement under transoesophageal echocardiography (TEE) control, a 15F to 19F arterial cannula and a 17F to 23F venous cannula were inserted into the femoral vessels. We routinely inserted an additional percutaneous 5F cannula distally into the femoral artery to avoid deleterious leg ischemia. If repeated efforts at percutaneous cannulation failed, a surgical exposure of the femoral vessels was performed, and cannulas were inserted under direct vision. Before cannulation, patients received a heparin bolus (40 to 80 units/kg); during ECMO, heparin was administered continuously to maintain activated clotting time between 200 s and 250 s.

Maintainance of adequate systemic blood flow was monitored by mean arterial pressure, blood lactate concentrations, central or mixed venous oxygen saturation, and urine output. Mean arterial pressure was maintained between 50 and 80 mm Hg with vasopressor or vasodilator administration. A pulsatile arterial pressure tracing indicated residual left ventricular myocardial contractility facilitating left ventricular drainage, while being supported with a right atrial to aortic extracorporeal system. Maintaining residual left ventricular ejection was also expected to reduce the risk of intracardiac clot formation. Whenever pulsations disappeared, volume expansion or inotropic support were immediately started until pulsatile systemic blood flow reappeared.

After ECMO implantation, early assessment of neurologic status was initiated with serial neurologic examination and computed tomography of the brain to assess for hypoxic injury or relevant cerebral hemorrhage. In patients who demonstrated sufficient cerebral, hepatic, renal, and pulmonary function, major contraindications for heart transplantation were excluded by serology for HIV and hepatitis C virus and total body computed tomography scan to exclude malignancy.

After an initial stabilization (minimum 24 hours), weaning attempts from ECMO were monitored by means of transesophageal echocardiography and measurement of central venous pressure, wedge pressure, arterial blood pressure, and mixed venous oxygen saturation. If weaning from ECMO support was not possible, another attempt was performed 12 to 24 hours later. In case of weaning failure, VAD implantation was usually considered after 72 hours.

Contraindications for VAD implantation were absolute contraindications to heart transplantation (malignancies, HIV infection), severe neurologic dysfunction (stroke, cerebral hemorrhage, diffuse hypoxic lesions after CPR), multiorgan failure, and sepsis.

In all patients receiving VAD support, a paracorporeal pulsatile VAD was implanted (Thoratec Corp, Pleasanton, CA, or Berlin Heart, Berlin, Germany). Left heart support was achieved by cannulating the apex of the left ventricle and the ascending aorta; for right heart support, the right atrium and the pulmonary artery were cannulated. Postoperative anticoagulation consisted of coumarins together with a platelet aggregation inhibitor at low dosage.

After stabilization, patients either went for recovery of myocardial function and weaning from VAD support (bridge to recovery) or for heart transplantation (bridge to transplant).

Data Analysis
Data analysis was performed with SPSS for Windows. Comparison of means was performed using the independent sample t test and Mann-Whitney test for nonparametric data. Categorical variables were analyzed with the {chi}2 test or Fisher's exact test. Multivariate analysis was performed using the Cox regression model. Survival curves were compared by the log-rank test. Statistical significance was defined as p value less than 0.05.


   Results
Top
 Abstract
 Introduction
 Patients and Methods
 Results
Comment
 References
 
Extracorporeal membrane oxygenation was used in 131 patients for conservatively intractable cardiogenic shock, with a mean ECMO support of 2.9 days (Table 1).

Fifty-two patients (40%) died during ECMO support (mean ECMO support, 2.44 days), in most cases owing to multiorgan failure or sepsis. Forty-six patients (35%) were successfully weaned (acute heart failure 22.4%; acute on chronic heart failure 0%; postcardiotomy heart failure 53.2%), 5 patients (4%) were successfully transplanted during ECMO support, and in 28 patients (21%) a VAD was implanted (bridge to bridge). There was no significant difference in ECMO duration for these four groups.

Complications after ECMO implantation were uncontrollable bleeding after perforation of the femoral artery with subsequent death (n = 2), local bleeding requiring surgical revision (n = 8), intrathoracal bleeding requiring surgical revision (n = 5), retrograde aortic dissection with subsequent stent implantation (n = 2), leg ischemia due to thrombosis requiring surgical revision (n = 2), formation of an atrial thrombus left untreated (n = 1), and necessity of multiple oxygenator changes due to clot formation (n = 5).

In 28 patients, weaning from ECMO was not possible for hemodynamic reasons. As they fulfilled our criteria for either recovery or heart transplantation, a VAD was implanted; mean assist time was 49.9 days (Table 2).


View this table:
[in this window]
[in a new window]
  		Table 2. Demography and Outcome of All Bridge to Bridge Patients (n = 28)
 
Five patients received an isolated right ventricular assist device, a left ventricular assist device was used in 4 patients, and the remaining 19 patients needed biventricular support.

Fourteen patients (50%) died during VAD support. In 12 cases, multiorgan failure together with sepsis was the cause of death; 1 patient died from intracranial bleeding, and one from bleeding during VAD explantation and attempted heart transplantation. Fourteen patients (50%) became long-term survivors with a mean follow-up of 39 months. Eleven patients underwent heart transplantation (bridge to transplant), and in 3 patients weaning from VAD was possible (bridge to recovery). Twelve survivors have no impairments in daily life (New York Heart Association [NYHA] class I); 2 patients are in NYHA class II. One patient recovered after myocarditis, and she recently became a mother 3 years after weaning.

Complications after VAD implantation involved bleeding requiring surgical revision in 10 patients. Two patients died from bleeding complications, one of intracerebral hemorrhage, and 1 from uncontrollable bleeding during explantation of VAD and heart transplantation. One patient survived an intracranial bleeding, and 1 patient experienced a thrombembolic insult; both of them recovered without sequelae and were succefully transplanted. In 1 patient, multiple changings of VAD ventricles were necessary owing to clot formation, after which the patient was transplanted without any further problems.

Outcome analysis was performed using clinical data and laboratory values before ECMO implantation and VAD implantation (Table 3). Significant differences between survivors and nonsurvivors were found for status post-CPR, bilirubin level before ECMO, cardiac output before ECMO, bilirubin level before VAD implantation, and lactate level before VAD implantation. All other clinical variables and laboratory values, as well as the etiology of heart failure (Fig 1), did not show significant influence on survival.


View this table:
[in this window]
[in a new window]
  		Table 3. Outcome Analysis for Bridge to Bridge Patients (n = 28)
 

Figure 1
View larger version (17K):
[in this window]
[in a new window]
  		Fig 1. Survival according to etiology of heart failure (HF). (Mo = month.)

 
Multivariate analysis (Cox regression) revealed status post-CPR and lactate levels as independent risk factors (Table 4).


View this table:
[in this window]
[in a new window]
  		Table 4. Outcome Analysis for Bridge to Bridge Patients (Multivariate Analysis)
 

   Comment
Top
 Abstract
 Introduction
 Patients and Methods
 Results
 Comment
References
 
Extracorporeal membrane oxygenation support is a well-established technology that provides circulatory support with the possibility to recover from organ injury in patients who present with cardiac arrest or severe hemodynamic instability associated with multiorgan failure [12–15, 17]. The feasibility of "on-site" or emergent percutaneous cannulation may facilitate survival by avoiding ischemic neurologic damage while providing essential cardiac and end-organ perfusion [6]. Evaluation of patients for possible heart transplantation (total body computed tomography, neurologic examination, repeated echocardiography, serologic examination) is possible before VAD implantation [2, 3]. In patients with severe multiorgan failure not resolving after a few days of ECMO support, VAD implantation should not be done. In addition, in some cases presenting with postcardiotomy cardiogenic shock, weaning from ECMO is possible within hours or a few days; thus invasive and expensive VAD implantation can be avoided in these patients [12].

However, the use of ECMO for cardiac failure has its limitations. One major concern is the limited duration of support and the poor outcome associated with long-term support in adults. Patients cannot be mobilized with cannulas implanted in femoral vessels. Furthermore, patients with these devices in place have a risk for complications such as bleeding, infection and sepsis, severe neurologic injury, limb ischemia, and technical problems (pump failure) [1–6]. Left ventricular decompression may be inadequate, thus requiring catecholamine therapy to prevent pulmonary hypertension, edema, and hemorrhage [1, 3, 4, 6]. In addition, ECMO increased left ventricular afterload, thus negatively affecting myocardial recovery in several animal studies [8–11]. To overcome this special problem, additional use of an intra-aortic balloon pump is discussed for decreasing left ventricular afterload and therefore reducing wall stress, especially during the critical initial period [9]. The combined use of ECMO and intra-aortic balloon pump under clinical conditions resulted in weaning rates from 56.7% to 69% in patients with postcardiotomy heart failure [16, 17].

In our patients, ECMO and intra-aortic balloon pump were not used together. Weaning rates were satisfactory, especially in the postcardiotomy heart failure group. It can be speculated that the additional use of intra-aortic balloon pump might have further improved ventricular function and might have led to a higher weaning rate.

In the literature, the bridge to bridge concept is still controversially discussed. Magliato and associates [1] report on not acceptable survival rates in the bridge to bridge population and favor primary VAD implantation. Other authors prefer primary ECMO support and favor the bridge to bridge concept [2–4, 7, 13–15, 18–20]. In detail, the immediate transfer to VAD would allocate resources to patients who would not have survived or been good candidates for transplantation. In addition, direct transfer to VAD would have prolonged time to reestablishment of sufficient cardiac output and thus may have affected perfusion of all vital organs in these critically ill patients.

The aim of this study was to evaluate the outcome of bridge to bridge patients and to evaluate clinical variables and laboratory tests for their impact on outcome.At our center, all patients presenting with otherwise intractable cardiogenic shock are stabilized with ECMO support, as we do not use primary VAD implantation for these patients, for the reasons discussed above.

Duration of ECMO support had no influence on outcome after ECMO implantation (weaning, subsequent VAD implantation, heart transplantation, or death) and outcome after VAD implantation. At least two weaning attempts were performed before implanting a VAD: hemodynamic monitoring in these patients showed no or only little improvement despite ECMO support. Therefore, early VAD implantation was attempted to avoid complications associated with prolonged ECMO support when no improvement in cardiac function was observed.

Data analysis of our patients revealed successful immediate circulatory support: blood lactate levels were lower before VAD implantation than before ECMO support. However, as a sign of advanced cardiogenic shock in nonsurvivors, not only lactate blood levels but also liver function tests were elevated in comparison with survivors; multivariate analysis revealed status post-CPR and lactate levels as independent risk factors. This was true for the time before ECMO implantation as well as before VAD implantation. Red and white blood cell count as well as renal function parameters showed no difference between survivors and nonsurvivors, as blood products were substituted as required, and in case of renal failure continuous hemofiltration was initiated.

Overall survival was 50%, which is satisfactory in comparison with other series [1–4, 21].

From our experience, we would recommend that initial stabilization with ECMO support should be attempted for all patients presenting with severe cardiac failure or cardiogenic shock. Extracorporeal membrane oxygenation implantation is less expensive than other forms of mechanical circulatory support and can be performed without major complications in the majority of patients and provides immediate sufficient organ perfusion. If implanted in an early state of refractory heart failure, it may prevent deleterious multiorgan failure. Additional use of intra-aortic balloon pump can be beneficial; experimental as well as clinical studies have revealed positive impact due to reduction of afterload.

Before VAD implantation, patients should be screened exactly for possible risk factors. In this study, clinical variables could be identified that were associated with a poor outcome: the mortality rate was high if blood lactate levels and liver function tests were still significantly elevated after ECMO support as a sign of advanced organ malperfusion and already severely affected liver function. In addition, patients after CPR had a significant higher mortality rate.

The combination of these risk factors might be detrimental as the general condition of such patients seems to be too poor, so that they do not tolerate VAD implantation anymore. At our center, we have refused VAD implantation recently for a patient whose liver function did not recover after ECMO support, because of the poor prognosis.

In summary, our results show that ECMO support can immediately stabilize circulation and provide organ perfusion in patients presenting with intractable cardiogenic shock. However, the mortality rate is extremely high among patients with persisting lactic acidosis and severely impaired liver function despite VAD support. Therefore, VAD implantation for patients after CPR together with elevated lactate and bilirubin levels despite ECMO support should be considered very carefully.


   References
Top
 Abstract
 Introduction
 Patients and Methods
 Results
 Comment
 References
 

  1. Magliato KE, Kleisli T, Soukiasian HJ, et al. Biventricular support in patients with profound cardiogenic shocka single center experience. ASAIO J 2003;49:475-479.[Medline]
  2. Bowen FW, Carboni AF, O'Hara ML, et al. Application of "double bridge mechanical" resuscitation for profound cardiogenic shock leading to transplantation Ann Thorac Surg 2001;72:86-90.[Abstract/Free Full Text]
  3. Pagani FD, Lynch W, Swaniker F, et al. Extracorporeal life support to left ventricular assist device bridge to heart transplant—a strategy to optimize survival and resource utilization Circulation 1999;100(Suppl 2):206-210.
  4. Pagani FD, Aaronson KD, Swaniker F, Bartlett RH. The use of extracorporeal life support in adult patients with primary cardiac failure as a bridge to implantable left ventricular assist device Ann Thorac Surg 2001;71(Suppl):77-81.
  5. Hoy FBY, Mueller DK, Geiss DM, et al. Bridge to recovery for postcardiotomy failureis there still a role for centrifugal pumps?. Ann Thorac Surg 2000;70:1259-1263.[Abstract/Free Full Text]
  6. Schwarz B, Mair P, Margreiter J, et al. Experience with percutaneous venoarterial cardiopulmonary bypass for emergency circulatory support Crit Care Med 2003;31:758-764.[Medline]
  7. Wang SS, Wen-Je K, Chen YS, Hsu RB, Chou NK, Chu SH. Mechanical bridge with extracorporeal membrane oxygenation and ventricular assist device to heart transplantation Artific Organs 2001;25:599-602.
  8. Bavaria JE, Ratcliffe MB, Gupta KB, Wenger RK, Bogen DK, Edmunds LH. Changes in left ventricular systolic wall stress during biventricular circulatory assistance Ann Thorac Surg 1988;45:526-532.[Abstract]
  9. Bavaria JE, Furukawa S, Kreiner G, Gupta KB, Streicher J, Edmunds LH. Effect of circulatory assist devices on stunned myocardium Ann Thorac Surg 1990;49:123-128.[Abstract]
  10. Ratcliffe MB, Bavaria JE, Wenger RK, Bogen DK, Edmunds LH. Left ventricular mechanics of ejecting, postischemic hearts during left ventricularcirculatory assistance J Thorac Cardiovasc Surg 1991;101:245-255.[Abstract]
  11. Seo T, Ito T, Iio K, Kato J, Takagi H. Experimental study on the hemodynamic effects of veno-arterial extracorporeal membrane oxygenation with an automatically driven blood pump on puppies Artific Organs 1991;15:402-407.
  12. Doll N, Kiaii B, Borger M, et al. Five-year results of 219 consecutive patients treated with extracorporeal membrane oxygenation for refractory postoperative cardiogenic shock Ann Thorac Surg 2004;77:151-157.[Abstract/Free Full Text]
  13. Chen YS, Ko WJ, Lin FY, et al. Preliminary result of an algorithm to select proper ventricular assist devices for high risk patients with extracorporeal membrane oxygenation support J Heart Lung Transplant 2001;20:850-857.[Medline]
  14. Levi D, Marelli D, Plunkett M, et al. Use of assist devices and ECMO to bridge pediatric patients with cardiomyopathy to transplantation J Heart Lung Transplant 2002;21:760-770.[Medline]
  15. Kihara S, Kawai A, Endo M, Koyangi H, Kurosawa H. Extracorporeal membrane oxygenation and left ventricular assist devicea case of double mechanical bridge. Heart Vessels 2002;16:164-166.[Medline]
  16. Hata M, Shiono M, Orime Y, et al. Strategy of circulatory support with percutaneous cardiopulmonary support Artific Organs 2000;24:636-639.
  17. Murashita T, Eya K, Miyatake T, et al. Outcome of the perioperative use of percutaneous cardiopulmonary support for adult cardiac surgeryfactors affecting hospital mortality. Artific Organs 2004;28:189-195.
  18. McBride LR, Naunheim KS, Fiore AC, et al. Risk analysis in patients bridged to transplantation Ann Thorac Surg 2001;71:1839-1844.[Abstract/Free Full Text]
  19. Pagani FD, Aaronson KD, Dyke DB, Wright S, Swaniker F, Bartlett RH. Assessment of an extracorporeal life support to LVAD bridge to heart transplantation strategy Ann Thorac Surg 2000;70:1977-1985.[Abstract/Free Full Text]
  20. Razzouk AJ, Cecere R, Gundry SR, Wang N, Bailey LL. Emergency implantation of a left ventricular assist device in adolescents with biventricular failure ASAIO J 2000;46:573-575.[Medline]
  21. Loebe M, Koerner MM, Lafuente JA, Noon GP. Patient selection for assist devicesbridge to transplant. Curr Opin Cardiol 2003;18:141-146.[Medline]



This article has been cited by other articles:


Home page
 Eur. J. Cardiothorac. Surg.Home page
M. Tajik and M. G. Cardarelli
Extracorporeal membrane oxygenation after cardiac arrest in children: what do we know?
Eur. J. Cardiothorac. Surg., March 1, 2008; 33(3): 409 - 417.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
H. R. Reynolds and J. S. Hochman
Cardiogenic Shock: Current Concepts and Improving Outcomes
Circulation, February 5, 2008; 117(5): 686 - 697.
[Full Text] [PDF]

Home page
 J. Thorac. Cardiovasc. Surg.Home page
E. Ruttmann, A. Weissenbacher, H. Ulmer, L. Muller, D. Hofer, J. Kilo, W. Rabl, B. Schwarz, G. Laufer, H. Antretter, et al.
Prolonged extracorporeal membrane oxygenation-assisted support provides improved survival in hypothermic patients with cardiocirculatory arrest
J. Thorac. Cardiovasc. Surg., September 1, 2007; 134(3): 594 - 600.
[Abstract] [Full Text] [PDF]

Home page
 J. Thorac. Cardiovasc. Surg.Home page
R. John, K. Liao, K. Lietz, F. Kamdar, M. Colvin-Adams, A. Boyle, L. Miller, and L. Joyce
Experience with the Levitronix CentriMag circulatory support system as a bridge to decision in patients with refractory acute cardiogenic shock and multisystem organ failure
J. Thorac. Cardiovasc. Surg., August 1, 2007; 134(2): 351 - 358.
[Abstract] [Full Text] [PDF]

Home page
 Ann. Thorac. Surg.Home page
J. Copeland
Invited commentary.
Ann. Thorac. Surg., July 1, 2006; 82(1): 33 - 34.
[Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to Personal Folders
Right arrow Download to citation manager
Right arrow Author home page(s):
Juliane Kilo
Herwig Antretter
Right arrow Permission Requests
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hoefer, D.
Right arrow Articles by Antretter, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hoefer, D.
Right arrow Articles by Antretter, H.
Related Collections
Right arrow Mechanical Circulatory Assistance

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
ANN THORAC SURG ASIAN CARDIOVASC THORAC ANN EUR J CARDIOTHORAC SURG
J THORAC CARDIOVASC SURG ICVTS ALL CTSNet JOURNALS