101
|
Ripamonti M, Viganò A, Moriggi M, Milano G, von Segesser LK, Samaja M, Gelfi C. Cytochrome c oxidase expression in chronic and intermittent hypoxia rat gastrocnemius muscle quantitated by CE. Electrophoresis 2007; 27:3897-903. [PMID: 16972301 DOI: 10.1002/elps.200600104] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We investigated the effects of hypoxia and intermittent hypoxia in rat muscle by quantitating the expression of genes encoding cytochrome c oxidase (CytOx) subunits I, II and IV, and ribosomal 12S RNA. The quantitative assessment was made by CE in a polymer network, laser being used to facilitate the detection of induced fluorescence. Constant and intermittent hypoxia influence gene expression and ribosomal activity to different degrees. We found constant hypoxia to be accompanied by an increment in the mitochondrial CytOx subunit transcripts II and I and 12S ribosomal subunit, whereas the nuclear subunit (IV) remained unchanged. No changes were observed in intermittent hypoxic rats. Despite the increment in messenger expression, the decrease in enzyme activity was accompanied by a decrease in citrate synthase activity, a marker of mitochondrial function. The increment in CytOx mitochondrial subunits messengers and ribosomal 12S RNA under prolonged chronic hypoxia could be a consequence of reduced protein synthesis that leads to messenger accumulation.
Collapse
|
102
|
von Segesser LK. Perfusion techniques during surgery of the thoracic and thoraco-abdominal aorta: the veno-arterial bypass. Multimed Man Cardiothorac Surg 2007; 2007:mmcts.2006.002535. [PMID: 24414322 DOI: 10.1510/mmcts.2006.002535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Open repair of the descending thoracic aorta and the thoraco-abdominal aorta remains a challenging procedure. On the proximal side, pressure overload in the supra-aortic territories and pump failure are just two examples for undesirable effects of descending thoracic aortic cross-clamping which may end with a disaster. On the distal side, potential problems include among others, paraplegia, renal failure, visceral and peripheral ischemia. Finally, there are per-procedural issues like hypoxia due to single lung ventilation, uncontrollable inflow or backflow, excessive blood loss, unrealistic time constraints for systematic revascularization of intercostals arteries etc. Partial (femoro-femoral) cardiopulmonary bypass provides answers to many of the issues raised above. In addition, perfusion with heparin coated equipment allowing for significant reduction of anticoagulation has been shown to be useful for maintaining the hemostatic potential of the patient and limiting blood loss. Our current approach to perfusion for descending thoracic and thoraco-abdominal aneurysm repair has evolved into a versatile cardiopulmonary bypass strategy allowing for rapid conversion from partial cardiopulmonary bypass with peripheral cannulation to full, and if necessary, central, cardiopulmonary bypass, and all sorts of combinations including deep hypothermic circulatory arrest.
Collapse
|
103
|
Tozzi P, Pawelec-Wojtalic M, Bukowska D, Argitis V, von Segesser LK. Endoscopic off-pump aortic valve replacement: does the pericardial cuff improve the sutureless closure of left ventricular access? Eur J Cardiothorac Surg 2007; 31:22-5. [PMID: 16952457 DOI: 10.1016/j.ejcts.2006.07.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2006] [Revised: 06/25/2006] [Accepted: 07/04/2006] [Indexed: 11/29/2022] Open
Abstract
OBJECTIVE Off-pump trans left ventricular approach provides more precise deployment of stented aortic valve of any size with respect to the endovascular replacement. One of the key steps of this procedure is the ventricle repair after catheter withdrawing. We designed an animal study to compare the consistency of a sutureless repair of the left ventricle access using nitinol occluder with and without pericardial cuff on the ventricular side. METHODS Material description: The Amplatz-nitinol occluder consists of two square heads squeezing ventricle wall in between them, sealing the defect. To improve its sealing property, a pericardial patch was sutured to the ventricular head of the occluder. Animal study setup: In adult pigs, a 30F sheath was inserted into the epigastric area through the cardiac apex, up to the left ventricle, simulating the approach for off-pump aortic valve replacement. The sheath was then removed and the ventricle closed with standard occluder in half of the animals, and cuffed occluder in the other half. Animals were followed-up for 3h, collecting haemodynamics data and pericardial bleeding. RESULTS Device was successfully deployed in 12 animals in less than 1min. In the group where the standard occluder was used, bleeding during the deployment was 80+/-20ml and after the deployment was 800+/-20ml over 3h. In the group where the cuffed occluder was used, bleeding during the deployment was 85+/-20ml and after the deployment was 100+/-5ml over 3h. In the cuffed group, bleeding was significantly lower than the standard group, p-value being <0.001. CONCLUSIONS The occluder is easy to use and the pericardial cuff dramatically increases its efficacy as demonstrated by a significant reduction of blood loss. The cuffed occluder opens the way for endoscopic, off-pump, transventricular aortic valve replacement.
Collapse
|
104
|
Jegger D, Mallik AS, Nasratullah M, Jeanrenaud X, da Silva R, Tevaearai H, von Segesser LK, Stergiopulos N. The effect of a myocardial infarction on the normalized time-varying elastance curve. J Appl Physiol (1985) 2006; 102:1123-9. [PMID: 17158245 DOI: 10.1152/japplphysiol.00976.2006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It has been suggested that the shape of the normalized time-varying elastance curve [E(n)(t(n))] is conserved in different cardiac pathologies. We hypothesize, however, that the E(n)(t(n)) differs quantitatively after myocardial infarction (MI). Sprague-Dawley rats (n = 9) were anesthetized, and the left anterior descending coronary artery was ligated to provoke the MI. A sham-operated control group (CTRL) (n = 10) was treated without the MI. Two months later, a conductance catheter was inserted into the left ventricle (LV). The LV pressure and volume were measured and the E(n)(t(n)) derived. Slopes of E(n)(t(n)) during the preejection period (alpha(PEP)), ejection period (alpha(EP)), and their ratio (beta = alpha(EP)/alpha(PEP)) were calculated, together with the characteristic decay time during isovolumic relaxation (tau) and the normalized elastance at end diastole (E(min)(n)). MI provoked significant LV chamber dilatation, thus a loss in cardiac output (-33%), ejection fraction (-40%), and stroke volume (-30%) (P < 0.05). Also, it caused significant calcium increase (17-fold), fibrosis (2-fold), and LV hypertrophy. End-systolic elastance dropped from 0.66 +/- 0.31 mmHg/microl (CTRL) to 0.34 +/- 0.11 mmHg/microl (MI) (P < 0.05). Normalized elastance was significantly reduced in the MI group during the preejection, ejection, and diastolic periods (P < 0.05). The slope of E(n)(t(n)) during the alpha(PEP) and beta were significantly altered after MI (P < 0.05). Furthermore, tau and end-diastolic E(min)(n) were both significantly augmented in the MI group. We conclude that the E(n)(t(n)) differs quantitatively in all phases of the heart cycle, between normal and hearts post-MI. This should be considered when utilizing the single-beat concept.
Collapse
|
105
|
Künzli A, Zingg PO, Zünd G, Leskosek B, von Segesser LK. Does retrograde cerebral perfusion via superior vena cava cannulation protect the brain? Eur J Cardiothorac Surg 2006; 30:906-9. [PMID: 17071098 DOI: 10.1016/j.ejcts.2006.08.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2006] [Revised: 07/11/2006] [Accepted: 08/09/2006] [Indexed: 10/24/2022] Open
Abstract
OBJECTIVE The retrograde cerebral perfusion via cannulation of the superior vena cava is a widespread method for optimising protection of the brain during hypothermic circulatory arrest. METHODS In 14 cadavers (8 females, 6 males) of the local department of pathology, an examination was performed to check the competence of the valves of the internal jugular veins. After a complete preparation of the superior vena cava, the innominate vein and both internal jugular veins, ligating all side branches, a retrograde perfusion on 7 cadavers was installed, documenting flow and pressure of each internal jugular vein (IJV) in vitro. Afterwards, the veins were opened and their valves inspected. RESULTS In all 14 cadavers, anatomically and functionally competent valves on the right proximal IJV were found. Only 1/14 cadaver had no valve in the left proximal IJV. Additional rudimentary and incompetent valves could be identified in 1/14 cadaver on the distal right IJV, and in 2/14 cadavers on the left IJV. Retrograde flow measurement of 7/14 cadavers revealed 0 ml/min in 4/7 cadavers, 6 ml/min in 1/7, 340 ml/min in 1/7 and 2500 ml/min in 1/7 cadaver. CONCLUSIONS As a rule, anatomically and functionally competent valves in the proximal IJV are present. In human beings, they obstruct the direct retrograde inlet to the intracranial venous system, which suggests an unbalanced and unreliable perfusion of the brain. Therefore, retrograde cerebral perfusion by cannulating the superior vena cava may help flushing out embolism and supporting 'the cold jacket' of the brain. However, its effect of retrograde backflow cannot be a sign of adequate cerebral perfusion.
Collapse
|
106
|
Tozzi P, Borghi E, Haesler E, Siniscalchi G, Motti A, Hayoz D, von Segesser LK. Progress in cardiovascular anastomoses: will the vascular join replace Carrel's technique? Eur J Cardiothorac Surg 2006; 30:425-30. [PMID: 16859919 DOI: 10.1016/j.ejcts.2006.05.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Revised: 04/29/2006] [Accepted: 05/15/2006] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Vascular reconstructions are becoming challenging due to the comorbidity of the aging population and since the introduction of minimally invasive approaches. Many sutureless anastomosis devices have been designed to facilitate the cardiovascular surgeon's work and the vascular join (VJ) is one of these. We designed an animal study to assess its reliability and long-term efficacy. METHODS VJ allows the construction of end-to-end and end-to-side anastomoses. It consists of two metallic crowns fixed to the extremity of the two conduits so that vessel edges are joined layer by layer. There is no foreign material exposed to blood. In adult sheep both carotid arteries were prepared and severed. End-to-end anastomoses were performed using the VJ device on one side and the classical running suture technique on the other side. Animals were followed-up with Duplex-scan every 3 months and sacrificed after 12 months. Histopathological analysis was carried out. RESULTS In 20 animals all 22 sutureless anastomoses were successfully completed in less than 2 min versus 6 +/- 3 min for running suture. Duplex showed the occlusion of three controls and one sutureless anastomosis. Two controls and one sutureless had stenosis >50%. Histology showed very thin layer of myointimal hyperplasia (50 +/- 10 microm) in the sutureless group versus 300 +/- 27 microm in the control. No significant inflammatory reaction was detected. CONCLUSIONS VJ provides edge-to-edge vascular repair that can be considered the most physiological way to restore vessel continuity. For the first time, in healthy sheep, an anastomotic device provided better results than suture technique.
Collapse
|
107
|
von Segesser LK. Closure devices: the solution for repair of direct access apertures after valved stent implantation? Eur J Cardiothorac Surg 2006; 30:2-3. [PMID: 16730191 DOI: 10.1016/j.ejcts.2006.04.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2006] [Revised: 04/07/2006] [Accepted: 04/07/2006] [Indexed: 11/16/2022] Open
|
108
|
Sekarski N, Di Bernardo S, Mivelaz Y, Meijboom E, von Segesser LK. [Univentricular hearts: long-term follow-up, complications and criteria for reintervention]. REVUE MEDICALE SUISSE 2006; 2:1385-6, 1388-90, 1392. [PMID: 16786954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Univentricular hearts are complex and heterogeneous congenital heart defects. Treatment is surgical and comprises several palliative operations to permit long term survival in these patients. Late complications are frequent and need intensive treatments. This review article focuses on the main surgical interventions, complications, follow-up and reintervention criteria in patients with univentricular hearts.
Collapse
|
109
|
Kappenberger L, Sigwart U, von Segesser LK, Sekarski N. [Congenital heart disease in adults: necessity of specialized long-term follow-up]. REVUE MEDICALE SUISSE 2006; 2:1371-2. [PMID: 16786951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
|
110
|
Bouchardy J, Huber C, Meijboom EJ, von Segesser LK, Sekarski N. [Tetralogy of Fallot: after the successful surgical correction...]. REVUE MEDICALE SUISSE 2006; 2:1376-9. [PMID: 16786952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Tetralogy of Fallot is the most frequent cyanotic congenital heart disease (1/10000 births). The first complete corrections have been done in the fifties, and we now have long-term follow-up studies, revealing the most frequent arrhythmias and anatomic substrates compromising the long-term survival of these patients. The purpose of this article is to review some of the long-term complications of these patients, who, even if they have been completely corrected, will never be cured.
Collapse
|
111
|
Morel S, Milano G, Ludunge KM, Corno AF, Samaja M, Fleury S, Bonny C, Kappenberger L, von Segesser LK, Vassalli G. Brief reoxygenation episodes during chronic hypoxia enhance posthypoxic recovery of LV function. Basic Res Cardiol 2006; 101:336-45. [PMID: 16705469 DOI: 10.1007/s00395-006-0596-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2005] [Accepted: 03/14/2006] [Indexed: 11/30/2022]
Abstract
Children with congenital cyanotic heart defects have worse outcomes after surgical repair of their heart defects compared with noncyanotic ones. Institution of extracorporeal circulation in these children exposes the cyanotic heart to reoxygenation injury. Mitogen-activated protein kinase (MAPK) signaling cascades are major regulators of cardiomyocyte function in acute hypoxia and reoxygenation. However, their roles in chronic hypoxia are incompletely understood. We determined myocardial activation of the three major MAPKs, c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase-1/2 (ERK1/2), and p38-MAPK in adult rats exposed to hypoxia (FIO2=0.10) for varying periods of time. Myocardial function was analyzed in isolated perfused hearts. Acute hypoxia stimulated JNK and p38-MAPK activation. Chronic hypoxia (2 weeks) was associated with increased p38-MAPK (but not JNK) activation, increased apoptosis, and impaired posthypoxic recovery of LV function. Brief normoxic episodes (1 h/day) during chronic hypoxia abolished p38-MAPK activation, stimulated MEK-ERK1/2 activation modestly, and restored posthypoxic LV function. In vivo p38-MAPK inhibition by SB203580 or SB202190 in chronically hypoxic rats restored posthypoxic LV function. These results indicate that sustained hypoxemia maintains p38-MAPK in a chronically activated state that predisposes to myocardial impairment upon reoxygenation. Brief normoxic episodes during chronic hypoxia prevent p38-MAPK activation and restore posthypoxic recovery of myocardial function.
Collapse
|
112
|
Jegger D, da Silva R, Jeanrenaud X, Nasratullah M, Tevaearai H, von Segesser LK, Segers P, Gaillard V, Atkinson J, Lartaud I, Stergiopulo N. Ventricular-arterial coupling in a rat model of reduced arterial compliance provoked by hypervitaminosis D and nicotine. Am J Physiol Heart Circ Physiol 2006; 291:H1942-51. [PMID: 16699077 DOI: 10.1152/ajpheart.00091.2006] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The vitamin D(3) and nicotine (VDN) model is one of isolated systolic hypertension (ISH) in which arterial calcification raises arterial stiffness and vascular impedance. The effects of VDN treatment on arterial and cardiac hemodynamics have been investigated; however, a complete analysis of ventricular-arterial interaction is lacking. Wistar rats were treated with VDN (VDN group, n = 9), and a control group (n = 10) was included without the VDN. At week 8, invasive indexes of cardiac function were obtained using a conductance catheter. Simultaneously, aortic pressure and flow were measured to derive vascular impedance and characterize ventricular-vascular interaction. VDN caused significant increases in systolic (138 +/- 6 vs. 116 +/- 13 mmHg, P < 0.01) and pulse (42 +/- 10 vs. 26 +/- 4 mmHg, P < 0.01) pressures with respect to control. Total arterial compliance decreased (0.12 +/- 0.08 vs. 0.21 +/- 0.04 ml/mmHg in control, P < 0.05), and pulse wave velocity increased significantly (8.8 +/- 2.5 vs. 5.1 +/- 2.0 m/s in control, P < 0.05). The arterial elastance and end-systolic elastance rose significantly in the VDN group (P < 0.05). Wave reflection was augmented in the VDN group, as reflected by the increase in the wave reflection coefficient (0.63 +/- 0.06 vs. 0.52 +/- 0.05 in control, P < 0.05) and the amplitude of the reflected pressure wave (13.3 +/- 3.1 vs. 8.4 +/- 1.0 mmHg in control, P < 0.05). We studied ventricular-arterial coupling in a VDN-induced rat model of reduced arterial compliance. The VDN treatment led to development of ISH and provoked alterations in cardiac function, arterial impedance, arterial function, and ventricular-arterial interaction, which in many aspects are similar to effects of an aged and stiffened arterial tree.
Collapse
|
113
|
Corno AF, Pozzi M, von Segesser LK. FloWatch and pseudoaneurysm: Complication versus coincidence. J Thorac Cardiovasc Surg 2006; 131:928-9; author reply 929. [PMID: 16580464 DOI: 10.1016/j.jtcvs.2005.11.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2005] [Revised: 11/02/2005] [Accepted: 11/08/2005] [Indexed: 11/19/2022]
|
114
|
Li J, Simeoni E, Fleury S, Dudler J, Fiorini E, Kappenberger L, von Segesser LK, Vassalli G. Gene transfer of soluble interleukin-17 receptor prolongs cardiac allograft survival in a rat model. Eur J Cardiothorac Surg 2006; 29:779-83. [PMID: 16520057 DOI: 10.1016/j.ejcts.2006.01.052] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2005] [Revised: 01/16/2006] [Accepted: 01/17/2006] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Interleukin-17 (IL-17), a potent proinflammatory cytokine, has been implicated in allograft rejection. We analyzed the efficacy of an adenoviral vector expressing an IL-17 inhibitor in delaying acute allograft rejection in a rat model of heart transplantation, and the biological mechanisms underlying the protective effect. METHODS We constructed an adenoviral vector expressing a soluble IL-17 receptor-immunoglobulin (IL-17R-Ig) fusion protein. IL-17R-Ig activity was assessed by inhibition of IL-17-induced IL-6 release in HeLa cells preincubated with the vector. Intracoronary vector administration was performed in F344 donor hearts that were placed as vascularized grafts into Lewis hosts. Inflammatory cells infiltrating the graft were analyzed by immunohistology. Cytokine transcripts in the graft were determined by real-time RT-PCR. RESULTS IL-17R-Ig gene transfer resulted in prolonged allograft survival (16.1+/-3.1 days vs 10.3+/-2.5 days with control virus and 10.1+/-2.1 days with virus dilution buffer alone; p<0.001). IL-17R-Ig gene transfer reduced inflammatory cell infiltrates, especially monocytes/macrophages and CD4+ T cells (p<0.05). It also reduced intragraft cytokine transcripts for interferon-gamma and transforming growth factor-beta (p<0.05) and, to a lesser extent, IL-1beta and tumor necrosis factor-alpha (p=0.083). CONCLUSIONS Local expression of soluble IL-17 receptor-immunoglobulin attenuates T helper type 1 (Th1) cytokine responses and leukocyte infiltration in rat cardiac allografts, thereby mediating prolonged graft survival. Intragraft IL-17 inhibition may be useful as an adjuvant therapy to systemic immunosuppression in heart transplantation.
Collapse
|
115
|
Huber CH, von Segesser LK. Direct Access Valve Replacement (DAVR) — are we entering a new era in cardiac surgery?☆. Eur J Cardiothorac Surg 2006; 29:380-5. [PMID: 16426856 DOI: 10.1016/j.ejcts.2005.12.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2005] [Revised: 12/04/2005] [Accepted: 12/06/2005] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE This study validates the off-pump antegrade trans-ventricular route for ultrasound-guided direct access aortic valve replacement. Direct access aortic valve replacement using a transthoracic and valved stent-based approach offers numerous advantages over the remote access percutaneous approach and may one day provide an alternative treatment modality for aortic valve disease. METHODS Valved stents were implanted off-pump in 17 pigs (72.10+/-8.4 kg) via the direct access transapical approach using a left-sided mini-thoracotomy and continuous ultrasonic and fluoroscopic guidance. Acute valved stent function was studied with intravascular and two-dimensional intracardiac ultrasound. The invasive valve gradient was assessed with pull-back pressure catheter. All valved stents were tested in vitro before insertion. Macroscopic analysis was performed at necropsy. RESULTS In 11 of the 17 pigs, valved stents were delivered to the target site over the native aortic valve leaflets without interference of coronary blood flow and with good acute valve function. Three valved stents were deployed supra-annularly, two of those occluded the right coronary orifice and one the left coronary orifice, leading to fatal outcomes. Three valved stents dislodged into the left ventricle, one because of size-mismatch and two because of failure to unfold correctly. In 11 properly sized and deployed valved stents, two showed a moderate and one a severe paravalvular leak. CONCLUSIONS Seventeen pigs underwent direct access valve replacement of the aortic valve with deployment of a valved stent into the native aorta. Eleven valves observed for an average 5-h period showed satisfactory, postimplantation valve function.
Collapse
|
116
|
Jegger D, Chassot PG, Bernath MA, Horisberger J, Gersbach P, Tozzi P, Delay D, von Segesser LK. A novel technique using echocardiography to evaluate venous cannula performance perioperatively in CPB cardiac surgery. Eur J Cardiothorac Surg 2006; 29:525-9. [PMID: 16476552 DOI: 10.1016/j.ejcts.2005.12.050] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Revised: 11/06/2005] [Accepted: 12/21/2005] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE Transthoracic echocardiography (TTE) has been used clinically to disobstruct venous drainage cannula and to optimise placement of venous cannulae in the vena cava but it has never been used to evaluate performance capabilities. Also, little progress has been made in venous cannula design in order to optimise venous return to the heart lung machine. We designed a self-expandable Smartcanula (SC) and analysed its performance capability using echocardiography. METHODS An epicardial echocardiography probe was placed over the SC or control cannula (CTRL) and a Doppler image was obtained. Mean (V(m)) and maximum (V(max)) velocities, flow and diameter were obtained. Also, pressure drop (DeltaP(CPB)) was obtained between the central venous pressure and inlet to venous reservoir. LDH and Free Hb were also compared in 30 patients. Comparison was made between the two groups using the student's t-test with statistical significance established when p<0.05. RESULTS Age for the SC and CC groups were 61.6+/-17.6 years and 64.6+/-13.1 years, respectively. Weight was 70.3+/-11.6 kg and 72.8+/-14.4 kg, respectively. BSA was 1.80+/-0.2 m(2) and 1.82+/-0.2 m(2), respectively. CPB times were 114+/-53 min and 108+/-44 min, respectively. Cross-clamp time was 59+/-15 min and 76+/-29 min, respectively (p=NS). Free-Hb was 568+/-142 U/l versus 549+/-271 U/l post-CPB for the SC and CC, respectively (p=NS). LDH was 335+/-73 mg/l versus 354+/-116 mg/l for the SC and CC, respectively (p=NS). V(m) was 89+/-10 cm/s (SC) versus 63+/-3 cm/s (CC), V(max) was 139+/-23 cm/s (SC) versus 93+/-11 cm/s (CC) (both p<0.01). DeltaP(CPB) was 30+/-10 mmHg (SC) versus 43+/-13 mmHg (CC) (p<0.05). A Bland-Altman test showed good agreement between the two devices used concerning flow rate calculations between CPB and TTE (bias 300 ml+/-700 ml standard deviation). CONCLUSIONS This novel Smartcanula design, due to its self-expanding principle, provides superior flow characteristics compared to classic two stage venous cannula used for adult CPB surgery. No detrimental effects were observed concerning blood damage. Echocardiography was effective in analysing venous cannula performance and velocity patterns.
Collapse
|
117
|
Simeoni E, Vassalli G, Seydoux C, Ramsay D, Noll G, von Segesser LK, Fleury S. CCR5, RANTES and CX3CR1 polymorphisms: possible genetic links with acute heart rejection. Transplantation 2006; 80:1309-15. [PMID: 16314800 DOI: 10.1097/01.tp.0000178378.53616.ca] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The inflammation response is modulated by the elaborated chemokine-chemokine receptor system, which also plays an important role in the development of acute rejection (AR). In this study, we hypothesized that functional genetic variants of some of these modulatory proteins might influence the outcome of AR. METHODS In a retrospective analysis of a cohort of heart transplanted patients (n=158), we examined eight polymorphisms in four genes implicated in this inflammatory process: RANTES, CCR5, CCR2 and CX3CR1. On the basis of timing occurrence, AR episodes (grade>or= 3A) were classified in "early" (0-3 months posttransplantation; EAR) or "late" outcomes (4-12 months posttransplantation; LAR). RESULTS The incidences of EAR and LAR were 57.6% and 41%, respectively. Number of LAR episodes was significantly higher in subjects that have already experienced one or more EAR episodes, as compared to subjects that had no EAR (median [25%-75%]: 4 () vs. 1 [1-2.5] respectively; P<0.0001). Statistical univariate analysis showed that none of the mentioned polymorphisms were correlated with EAR or LAR. However, allele-allele association analysis showed that subjects carrying both the CX3CR1 249I allele and CCR5 No-E haplotypes were significantly at lower risk of experiencing EAR (OR=0.2 [95%-CI=0.1-0.5], P=0.001). In contrast subjects carrying both the CCR5 E haplotype and the RANTES -403A allele were significantly at higher risk to develop LAR (OR=8.1 [95%-CI=2.3-28.7], P=0.002). CONCLUSIONS This exploratory study in heart transplantation suggests that the outcomes of EAR and LAR episodes may be influenced by genetic variant interactions such as "CX3CR1 249I*CCR5 No-E" and "CCR5 E*RANTES -403A."
Collapse
|
118
|
Corno AF, Prosi M, Fridez P, Zunino P, Quarteroni A, von Segesser LK. The non-circular shape of FloWatch®-PAB prevents the need for pulmonary artery reconstruction after banding.Computational fluid dynamics and clinical correlations. Eur J Cardiothorac Surg 2006; 29:93-9. [PMID: 16337404 DOI: 10.1016/j.ejcts.2005.10.029] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2005] [Revised: 09/16/2005] [Accepted: 10/17/2005] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVE To evaluate the differences between non-circular shape of FloWatch-PAB and conventional pulmonary artery (PA) banding. METHODS Geometrical analysis. Conventional banding and FloWatch-PAB perimeters were plotted against cross-sections. Computational fluid dynamics (CFD) model. CFD compared non-circular FloWatch-PAB cross-sections with conventional banding regarding pressure gradients. Clinical data. Seven children, median age 2 months (7 days to 3 years), median weight 4.2 kg (3.2-9.8 kg), with complex congenital heart defects underwent PA banding with FloWatch-PAB implantation. RESULTS Geometrical analysis. Conventional banding: progressive reduction of cross-sections was accompanied by progressive reduction of PA perimeters. FloWatch-PAB: with equal reduction of cross-sections the PA perimeter remained constant. CFD model. Non-circular and circular banding provided same trans-banding pressure gradients for same cross-sections at any given flow. Clinical data. Mean PA internal diameter at banding was 13.3+/-4.5 mm. After a mean interval of 5.9+/-3.7 months, all children underwent intra-cardiac repair and simple FloWatch-PAB removal without PA reconstruction. Mean PA internal diameter with FloWatch-PAB removal increased from 3.0+/-0.8 to 12.4+/-4.5 mm (normal mean internal diameter for the age=9.9+/-1.6). No residual pressure gradient was recorded in correspondence of the site of the previous FloWatch-PAB implantation in 6/7 patients, 10 mmHg peak and 5 mmHg mean gradient in 1/7. CONCLUSIONS The non-circular shape of FloWatch-PAB can replace conventional circular banding with the following advantages: (a) the pressure gradient will remain essentially the same as for conventional circular banding for any given cross-section, but with significantly smaller reduction of PA perimeter; and (b) PA reconstruction at the time of de-banding for intra-cardiac repair can be avoided.
Collapse
|
119
|
von Segesser LK. More CME — is this for me? Eur J Cardiothorac Surg 2005. [DOI: 10.1016/j.ejcts.2005.10.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
120
|
Jegger D, Jeanrenaud X, Nasratullah M, Chassot PG, Mallik A, Tevaearai H, von Segesser LK, Segers P, Stergiopulos N. Noninvasive Doppler-derived myocardial performance index in rats with myocardial infarction: validation and correlation by conductance catheter. Am J Physiol Heart Circ Physiol 2005; 290:H1540-8. [PMID: 16299257 DOI: 10.1152/ajpheart.00935.2005] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The rodent model of myocardial infarction (MI) is extensively used in heart failure studies. However, long-term follow-up of echocardiographic left ventricular (LV) function parameters such as the myocardial performance index (MPI) and its ratio with the fractional shortening (LVFS/MPI) has not been validated in conjunction with invasive indexes, such as those derived from the conductance catheter (CC). Sprague-Dawley rats with left anterior descending coronary artery ligation (MI group, n = 9) were compared with a sham-operated control group (n = 10) without MI. Transthoracic echocardiography (TTE) was performed every 2 wk over an 8-wk period, after which classic TTE parameters, especially MPI and LVFS/MPI, were compared with invasive indexes obtained by using a CC. Serial TTE data showed significant alterations in the majority of the noninvasive functional and structural parameters (classic and novel) studied in the presence of MI. Both MPI and LVFS/MPI significantly (P < 0.05 for all reported values) correlated with body weight (r = -0.58 and 0.76 for MPI and LVFS/MPI, respectively), preload recruitable stroke work (r = -0.61 and 0.63), LV end-diastolic pressure (LVEDP) (r = 0.82 and -0.80), end-diastolic volume (r = 0.61 and -0.58), and end-systolic volume (r = 0.46 and -0.48). Forward stepwise linear regression analysis revealed that, of all variables tested, LVEDP was the only independent determinant of MPI (r = 0.84) and LVFS/MPI (r = 0.83). We conclude that MPI and LVFS/MPI correlate strongly and better than the classic noninvasive TTE parameters with established, invasively assessed indexes of contractility, preload, and volumetry. These findings support the use of these two new noninvasive indexes for long-term analysis of the post-MI LV remodeling.
Collapse
|
121
|
Delay D, Lardi C, Jaussi A, von Segesser LK. Hepato-atrial anastomosis, the "other Senning operation" for treatment of Budd-Chiari syndrome. Swiss Med Wkly 2005; 135:235-7. [PMID: 15971116 DOI: 2005/15/smw-11002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
A now 36-year-old woman developed a suprahepatic inferior vena cava stenosis, 9 years after liver transplantation for extensive liver echinococcosis. The lesion was treated by percutaneous angioplasty and stenting. Five years later, recurrence of echinococosis with intrastent stenosis together with clinical symptoms, prompted surgical treatment. Hepato-atrial anastomosis was performed under cardiopulmonary bypass with good result.
Collapse
|
122
|
Ma L, Tozzi P, Huber CH, Taub S, Gerelle G, von Segesser LK. Double-crowned valved stents for off-pump mitral valve replacement☆. Eur J Cardiothorac Surg 2005; 28:194-8; discussion 198-9. [PMID: 15950482 DOI: 10.1016/j.ejcts.2004.12.068] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2004] [Revised: 12/11/2004] [Accepted: 12/17/2004] [Indexed: 10/25/2022] Open
Abstract
OBJECTIVE An animal model has been designed to assess the feasibility of off-pump mitral valve replacement using valved stents. METHODS Glutaraldehyde-preserved homograft was sutured inside a prosthetic tube (Dacron). Then, two self-expandable nitinol Z-stents were sutured on the external surface of the prosthesis in such a way to create two self-expanding crowns for fixation. In adult pigs and under general anesthesia, the left atrium was exposed through a left thoracotomy and atrio-ventricular roadmapping was performed with intravascular ultrasound (IVUS) and fluoroscopy. The double-crowned valved stents were loaded into a delivery sheath. The sheath was then introduced into the left atrium and the valved stents was deployed in mitral position in such a way that the part in between the two stents was at the level of the mitral annulus. Intracardiac Unltrasound (ICUS) was used to assess the valve function. Hemodynamic parameters were gathered as well. Animal survived for no more than 3h after the valve deployment and gross anatomy examination of the left heart was carried out. RESULTS The mean height of the valved stents was 29.4+/-0.2 mm, with an internal diameter of 20.4+/-1.0mm, and an external diameter of 25.5+/-0.8 mm. The procedure was successfully carried out in eight animals. In vivo evaluation showed a native mitral annulus diameter of 24.9+/-0.6 mm, and a mean mitral valve area of 421.4+/-17.5 mm2. ICUS showed a mild mitral regurgitation in three out of eight animals. Mean pressure gradient across the valved stents was 2.6+/-3.1 mmHg. Mean pressure gradient across the left ventricular outflow tract (LVOT) was 6.6+/-5.2 mmHg. The mean survival time was 97.5+/-56.3 min (survival time range was 40-180 min). One animal died due to the occlusion of the LVOT because of valved stents displacement. Postmortem evaluation confirmed correct positioning of the valved stent in the mitral position in seven out of eight animals. No atrial or ventricular lesions due to the valved stents were found. CONCLUSIONS Off-pump implantation of a self-expandable valved stent in the mitral position is technically feasible. Further studies will assess if this procedure is also feasible in humans.
Collapse
|
123
|
Huber CH, Cohn LH, von Segesser LK. Direct-Access Valve Replacement. J Am Coll Cardiol 2005; 46:366-70. [PMID: 16022969 DOI: 10.1016/j.jacc.2005.04.028] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2004] [Revised: 03/25/2005] [Accepted: 04/05/2005] [Indexed: 10/25/2022]
Abstract
OBJECTIVES This study validates the off-pump antegrade transventricular route for ultrasound-guided direct-access aortic valved stent implantation. BACKGROUND Direct-access aortic valved stent implantation offers numerous advantages over the remote-access percutaneous approach and may one day provide an alternative to surgical aortic valve replacement. METHODS Valved stents were implanted off-pump in 12 pigs (68.5.0 +/- 7.3 kg) via direct-access transapical approach using a left-sided mini-thoracotomy and continuous ultrasonic and fluoroscopic guidance. Acute valved stent function was studied with intravascular and intracardiac ultrasound. All valved stents were tested in vitro before insertion. Macroscopic analysis was performed at necropsy. RESULTS In 8 of 12 pigs, valved stents were delivered to the target site over the native aortic valve leaflets without interference of coronary blood flow and with good acute valve function. Two valved stents were deployed and supra-annularly occluded the coronary orifice, leading to fatal outcome. Two valved stents dislodged into the left ventricle, one because of size mismatch and one that failed to unfold correctly. CONCLUSIONS Twelve pigs underwent deployment of a valved stent in the aortic position. Six valves observed for an average 4.5-h period showed satisfactory postimplantation valve function.
Collapse
|
124
|
|
125
|
Delay D, Lardi C, Jaussi A, von Segesser LK. Hepato-atrial anastomosis, the "other Senning operation" for treatment of Budd-Chiari syndrome. Swiss Med Wkly 2005; 135:235-7. [PMID: 15971116 DOI: 10.4414/smw.2005.11002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
A now 36-year-old woman developed a suprahepatic inferior vena cava stenosis, 9 years after liver transplantation for extensive liver echinococcosis. The lesion was treated by percutaneous angioplasty and stenting. Five years later, recurrence of echinococosis with intrastent stenosis together with clinical symptoms, prompted surgical treatment. Hepato-atrial anastomosis was performed under cardiopulmonary bypass with good result.
Collapse
|