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Osinski V, Yellamilli A, Firulyova MM, Zhang MJ, Peck A, Auger JL, Faragher JL, Marath A, Voeller RK, O’Connell TD, Zaitsev K, Binstadt BA. Profibrotic VEGFR3-Dependent Lymphatic Vessel Growth in Autoimmune Valvular Carditis. Arterioscler Thromb Vasc Biol 2024; 44:807-821. [PMID: 38269589 PMCID: PMC10978259 DOI: 10.1161/atvbaha.123.320326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 01/11/2024] [Indexed: 01/26/2024]
Abstract
BACKGROUND Rheumatic heart disease is the major cause of valvular heart disease in developing nations. Endothelial cells (ECs) are considered crucial contributors to rheumatic heart disease, but greater insight into their roles in disease progression is needed. METHODS We used a Cdh5-driven EC lineage-tracing approach to identify and track ECs in the K/B.g7 model of autoimmune valvular carditis. Single-cell RNA sequencing was used to characterize the EC populations in control and inflamed mitral valves. Immunostaining and conventional histology were used to evaluate lineage tracing and validate single-cell RNA-sequencing findings. The effects of VEGFR3 (vascular endothelial growth factor receptor 3) and VEGF-C (vascular endothelial growth factor C) inhibitors were tested in vivo. The functional impact of mitral valve disease in the K/B.g7 mouse was evaluated using echocardiography. Finally, to translate our findings, we analyzed valves from human patients with rheumatic heart disease undergoing mitral valve replacements. RESULTS Lineage tracing in K/B.g7 mice revealed new capillary lymphatic vessels arising from valve surface ECs during the progression of disease in K/B.g7 mice. Unsupervised clustering of mitral valve single-cell RNA-sequencing data revealed novel lymphatic valve ECs that express a transcriptional profile distinct from other valve EC populations including the recently identified PROX1 (Prospero homeobox protein 1)+ lymphatic valve ECs. During disease progression, these newly identified lymphatic valve ECs expand and upregulate a profibrotic transcriptional profile. Inhibiting VEGFR3 through multiple approaches prevented expansion of this mitral valve lymphatic network. Echocardiography demonstrated that K/B.g7 mice have left ventricular dysfunction and mitral valve stenosis. Valve lymphatic density increased with age in K/B.g7 mice and correlated with worsened ventricular dysfunction. Importantly, human rheumatic valves contained similar lymphatics in greater numbers than nonrheumatic controls. CONCLUSIONS These studies reveal a novel mode of inflammation-associated, VEGFR3-dependent postnatal lymphangiogenesis in murine autoimmune valvular carditis, with similarities to human rheumatic heart disease.
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Affiliation(s)
- Victoria Osinski
- Department of Pediatrics and Center for Immunology, University of Minnesota, Minneapolis, MN
| | - Amritha Yellamilli
- Department of Pediatrics, Stanford School of Medicine, Palo Alto, CA
- Medical Scientist Training Program, University of Minnesota, Minneapolis, MN
| | - Maria M. Firulyova
- Almazov National Medical Research Centre, Saint-Petersburg, Russia
- Computer Technologies Laboratory, ITMO University, Saint Petersburg, Russia
| | - Michael J. Zhang
- Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis, MN
- Cardiovascular Division, Department of Medicine, University of Minnesota, Minneapolis, MN
| | - Alyssa Peck
- Department of Pediatrics and Center for Immunology, University of Minnesota, Minneapolis, MN
| | - Jennifer L. Auger
- Department of Pediatrics and Center for Immunology, University of Minnesota, Minneapolis, MN
| | - Jessica L. Faragher
- Department of Pediatrics and Center for Immunology, University of Minnesota, Minneapolis, MN
| | | | | | - Timothy D. O’Connell
- Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis, MN
| | - Konstantin Zaitsev
- Computer Technologies Laboratory, ITMO University, Saint Petersburg, Russia
| | - Bryce A. Binstadt
- Department of Pediatrics and Center for Immunology, University of Minnesota, Minneapolis, MN
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Aggarwal R, Siems C, Potel KN, Hingtgen A, Wang Q, Nijjar PS, Huddleston SJ, John R, Kelly RF, Voeller RK. New-onset postoperative atrial fibrillation after mitral valve surgery: Determinants and the effect on survival. JTCVS Open 2023; 16:305-320. [PMID: 38204696 PMCID: PMC10775066 DOI: 10.1016/j.xjon.2023.08.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 07/29/2023] [Accepted: 08/28/2023] [Indexed: 01/12/2024]
Abstract
Objective Mitral valve surgery (MVS) carries substantial risk of postoperative atrial fibrillation (PAF). Identifying patients who benefit from prophylactic left atrial appendage amputation (LAAA) or maze is ill-defined. To guide such interventions, we determined preoperative predictors of PAF and investigated 3-year survival of patients with PAF. Methods We performed a retrospective analysis of patients undergoing isolated MVS (N = 670) between 2011 and 2021. Patients with preoperative atrial fibrillation, LAAA or pulmonary vein isolation were excluded. Patient characteristics were compared between those without PAF and those who developed transient or prolonged PAF. Predictors of any PAF and prolonged PAF were identified using multivariable regression analysis. Results In total, 504 patients without preoperative atrial fibrillation underwent isolated MVS. Of them, 303 patients (60.2%) developed PAF; 138 (27.3%) developed transient and 165 (32.7%) developed prolonged (beyond 30 days) PAF. Patients with PAF were older (65.7 vs 54.3 years, P < .001), with larger left atria (4.8 vs 4.3 cm, P < .001), greater prevalence of hypertension (60% vs 47.8%, P < .05), and were New York Heart Association class III/IV (36% vs 8.5%, P < .001). Independent predictors of PAF included left atria volume index (odds ratio [OR], 1.02; P < .003), older age (OR, 1.04; P < .001), heart failure (OR, 6.73; P < .001), and sternotomy (OR, 2.19; P < .002). Age, heart failure, and sternotomy were independent predictors of prolonged PAF. Patients with PAF had greater mortality at 3 years compared with those without PAF (5.3% vs 0.5%, P < .005). On multivariable analysis, PAF was associated with increased mortality (hazard ratio, 7.81; P < .046). Conclusions PAF is common after MVS and associated with late mortality. Older age, advanced heart failure, and sternotomy are associated with prolonged PAF. These factors may identify patients who would benefit from prophylactic LAAA or ablation during MVS.
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Affiliation(s)
- Rishav Aggarwal
- Division of Cardiothoracic Surgery, Department of Surgery, University of Minnesota Medical School, Minneapolis, Minn
| | - Chesney Siems
- Division of Cardiothoracic Surgery, Department of Surgery, University of Minnesota Medical School, Minneapolis, Minn
| | - Koray N. Potel
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom
| | | | - Qi Wang
- Biostatistical Design and Analysis Center, Clinical and Translational Science Institute, University of Minnesota, Minneapolis, Minn
| | - Prabhjot S. Nijjar
- Cardiovascular Division, Department of Medicine, University of Minnesota Medical School, Minneapolis, Minn
| | - Stephen J. Huddleston
- Division of Cardiothoracic Surgery, Department of Surgery, University of Minnesota Medical School, Minneapolis, Minn
| | - Ranjit John
- Division of Cardiothoracic Surgery, Department of Surgery, University of Minnesota Medical School, Minneapolis, Minn
| | - Rosemary F. Kelly
- Division of Cardiothoracic Surgery, Department of Surgery, University of Minnesota Medical School, Minneapolis, Minn
| | - Rochus K. Voeller
- Division of Cardiothoracic Surgery, Department of Surgery, University of Minnesota Medical School, Minneapolis, Minn
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Wiputra H, Matsumoto S, Wagenseil JE, Braverman AC, Voeller RK, Barocas VH. Statistical shape representation of the thoracic aorta: accounting for major branches of the aortic arch. Comput Methods Biomech Biomed Engin 2023; 26:1557-1571. [PMID: 36165506 PMCID: PMC10040462 DOI: 10.1080/10255842.2022.2128672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 08/24/2022] [Accepted: 09/11/2022] [Indexed: 11/03/2022]
Abstract
Statistical shape modeling (SSM) is an emerging tool for risk assessment of thoracic aortic aneurysm. However, the head branches of the aortic arch are often excluded in SSM. We introduced an SSM strategy based on principal component analysis that accounts for aortic branches and applied it to a set of patient scans. Computational fluid dynamics were performed on the reconstructed geometries to identify the extent to which branch model accuracy affects the calculated wall shear stress (WSS) and pressure. Surface-averaged and location-specific values of pressure did not change significantly, but local WSS error was high near branches when inaccurately modeled.
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Affiliation(s)
- Hadi Wiputra
- Department of Biomedical Engineering, University of Minnesota
| | - Shion Matsumoto
- Department of Biomedical Engineering, University of Michigan
| | | | - Alan C. Braverman
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine
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Geirsson A, Owen CH, Binford RS, Voeller RK, Burke CR, McNeil JD, Wei LM, Badhwar V, Rankin JS. Aortic valve repair for isolated right coronary leaflet prolapse. JTCVS Tech 2022; 13:26-30. [PMID: 35711222 PMCID: PMC9196763 DOI: 10.1016/j.xjtc.2022.02.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 02/23/2022] [Indexed: 11/18/2022] Open
Abstract
Objectives Isolated right coronary leaflet prolapse is a common cause of nonaneurysmal aortic insufficiency, but can rarely occur in patients with proximal aortic aneurysms. Standardized techniques for routine autologous repair of this disorder are presented. Methods Most aortic valve leaflet prolapse is isolated to the right coronary leaflet, with hypertension and annular dilatation being contributory. Echocardiographically, a posteriorly eccentric aortic insufficiency jet together with "fracture" of the right leaflet tip are diagnostic. Primary repair includes internal geometric ring annuloplasty to downsize and reshape the annulus, together with central plication of the prolapsing leaflet. Thickened, scarred, or retracted noduli are released using an ultrasonic aspirator. The goal is to achieve equivalent coaptation heights of ≥8 mm for all 3 leaflets. Results Three videos of 6 cases are provided to illustrate these techniques. In the first, 3 patients are shown with classic isolated right leaflet prolapse. In the second and third videos, alternative pathologies are presented for contrast. Applying the reconstructive approaches of geometric ring annuloplasty, leaflet plication, and ultrasonic nodular release, excellent early and late repair outcomes are obtainable in most patients. Conclusions The combination of aortic ring annuloplasty, central leaflet plication, and ultrasonic nodular release allows routine and standardized repair of right coronary leaflet prolapse, either isolated or concomitant with aneurysm surgery.
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Affiliation(s)
- Arnar Geirsson
- Department of Cardiac Surgery, Yale University School of Medicine, New Haven, Conn
| | | | | | - Rochus K. Voeller
- Department of Cardiothoracic Surgery, University of Minnesota, Minneapolis, Minn
| | | | | | - Lawrence M. Wei
- Department of Cardiovascular and Thoracic Surgery, West Virginia University, Morgantown, WVa
| | - Vinay Badhwar
- Department of Cardiovascular and Thoracic Surgery, West Virginia University, Morgantown, WVa
| | - J. Scott Rankin
- Department of Cardiovascular and Thoracic Surgery, West Virginia University, Morgantown, WVa
- Address for reprints: J. Scott Rankin, MD, 1 Medical Center Drive, Morgantown, WV 26506.
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Castillo-Sang M, Nguyen TC, Voeller RK. Commentary: Ischemic mitral regurgitation: From annular restriction to papillary approximation, is it time to reconsider the lost technique? J Thorac Cardiovasc Surg 2020; 164:863-864. [PMID: 33218759 DOI: 10.1016/j.jtcvs.2020.10.056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 10/13/2020] [Accepted: 10/15/2020] [Indexed: 10/23/2022]
Affiliation(s)
- Mario Castillo-Sang
- Department of Cardiothoracic Surgery, Saint Elizabeth Healthcare, Edgewood, Ky.
| | - Tom C Nguyen
- Department of Cardiothoracic and Vascular Surgery, McGovern Medical School, University of Texas Health Science Houston, Houston, Tex
| | - Rochus K Voeller
- Division of Cardiothoracic Surgery, Department of Surgery, University of Minnesota Medical School, Minneapolis, Minn
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Castillo-Sang M, Bartone C, Palmer C, Truong VT, Kelly B, Voeller RK, Griffin J, Smith T, Raidt H, Answini GA. Fifty Percent Reduction in Narcotic Use After Minimally Invasive Cardiac Surgery Using Liposomal Bupivacaine. Innovations�(Phila) 2019; 14:512-518. [DOI: 10.1177/1556984519874030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objective Minimally invasive cardiac surgery via a right minithoracotomy (RMT) is a common approach to different valve pathologies, tumor resection, and atrial septal defect (ASD) closure. We studied intraoperative field block using liposomal bupivacaine (LB) in these operations. Methods Consecutive 171 minimally invasive RMTs (fourth intercostal space) were studied, and patients in cardiogenic or septic shock, intravenous drug abuse, and those re-explored were excluded ( n = 12). An early cohort was treated with standard postoperative analgesia while another underwent intraoperative field block with LB immediately after incision. We compared postoperative pain level, narcotic utilization (morphine milligram equivalent), and intensive care unit (ICU) and hospital length of stay. Results The procedures included 48 isolated mitral valve replacements (MVR); 2 MVR with other procedures; 93 mitral valve repairs (MVRr); 9 MVRr with other procedures; 4 isolated tricuspid valve repairs; 2 myxoma resections; 1 ASD closure. There were 13 patients in the non-LB group and 146 patients in the LB group. Use of LB decreased mean postoperative narcotic utilization by 50% ( P = 0.003). The LB group had lower pain levels on postoperative day 1 ( P = 0.039), which continued through postoperative day 5 ( P = 0.030). We found no difference in ICU or hospital length of stay between groups. There were no complications from LB field block. Conclusions LB field block decreases postoperative pain and narcotic utilization after cardiac surgery via a RMT, but it does not reduce length of stay. The technique is safe and should be considered in all patients undergoing RMT cardiac surgery.
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Affiliation(s)
| | | | | | - Vien T. Truong
- The Christ Hospital of Cincinnati, OH, USA
- The Linder Research Center, Cincinnati, OH, USA
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Voeller RK, Kelly R. Postcardiotomy shock: Which patients benefit from extracorporeal membrane oxygenation? J Thorac Cardiovasc Surg 2018; 156:1883-1884. [DOI: 10.1016/j.jtcvs.2018.06.084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 06/28/2018] [Indexed: 10/28/2022]
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Lee AM, Miller JR, Voeller RK, Zierer A, Lall SC, Schuessler RB, Damiano RJ, Melby SJ. A Simple Porcine Model of Inducible Sustained Atrial Fibrillation. Innovations 2016. [DOI: 10.1177/155698451601100115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Anson M. Lee
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO USA
| | - Jacob R. Miller
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO USA
| | - Rochus K. Voeller
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO USA
| | - Andreas Zierer
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO USA
| | - Shelly C. Lall
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO USA
| | - Richard B. Schuessler
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO USA
| | - Ralph J. Damiano
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO USA
| | - Spencer J. Melby
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO USA
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Robertson JO, Lee AM, Voeller RK, Damiano MS, Schuessler RB, Damiano RJ. Quantification of the functional consequences of atrial fibrillation and surgical ablation on the left atrium using cardiac magnetic resonance imaging. Eur J Cardiothorac Surg 2014; 46:720-8. [PMID: 24523494 DOI: 10.1093/ejcts/ezt656] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES The effect of atrial fibrillation (AF) on left atrial (LA) function has not been well defined and has been largely based on limited echocardiographic evaluation. This study examined the effect of AF and a subsequent Cox-Maze IV (CMIV) procedure on atrial function. METHODS Cardiac magnetic resonance imaging (cMRI) was performed in 20 healthy volunteers, 8 patients with paroxysmal atrial fibrillation (PAF) and 7 patients with persistent or long-standing persistent atrial fibrillation (LSP AF). Six of the PAF patients underwent surgical ablation with the CMIV procedure and 5 underwent both pre- and postoperative cMRIs. The persistent or LSP AF patients underwent only postoperative cMRIs because all scans were performed with patients in normal sinus rhythm. Volume-time curves throughout the cardiac cycle and regional wall shortening were evaluated using the cine images and compared across groups. RESULTS Compared with normal volunteers, patients with PAF had significantly decreased reservoir contribution to left ventricular (LV) filling (P = 0.0010), an increased conduit function contribution (P = 0.04) and preserved booster pump function (P = 0.14). Following the CMIV procedure, significant reductions were noted with respect to reservoir and booster pump function, with corresponding increases in conduit function. These differences were more drastic in patients with persistent/LSP AF. Regional wall motion was significantly reduced by PAF in all wall segments (P < 0.05), but was not further reduced by the CMIV. Despite changes in LA function, LV function was preserved following surgery. CONCLUSIONS PAF significantly altered LA function and has a detrimental effect on regional wall motion. Surgical intervention further altered LA function, but the reasons for this are likely multifactorial and not entirely related to the lesion set itself.
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Affiliation(s)
- Jason O Robertson
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St Louis, MO, USA
| | - Anson M Lee
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St Louis, MO, USA
| | - Rochus K Voeller
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St Louis, MO, USA
| | - Marci S Damiano
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St Louis, MO, USA
| | - Richard B Schuessler
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St Louis, MO, USA
| | - Ralph J Damiano
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St Louis, MO, USA
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Voeller RK, Epstein DJ, Guthrie TJ, Gandhi SK, Canter CE, Huddleston CB. Trends in the Indications and Survival in Pediatric Heart Transplants: A 24-year Single-Center Experience in 307 Patients. Ann Thorac Surg 2012; 94:807-15; discussion 815-6. [DOI: 10.1016/j.athoracsur.2012.02.052] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 02/05/2012] [Accepted: 02/08/2012] [Indexed: 11/30/2022]
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Abstract
The Cox maze procedure is an effective treatment of atrial fibrillation, with a long-term freedom from recurrence greater than 90%. The original procedure was highly invasive and required cardiopulmonary bypass. Modifications of the procedure that eliminate the need for cardiopulmonary bypass have been proposed, including use of alternative energy sources to replace cut-and-sew lesions with lines of ablation made from the epicardium on the beating heart. This has been challenging because atrial wall muscle thickness is extremely variable, and the muscle can be covered with an epicardial layer of fat. Moreover, the circulating intracavitary blood acts as a potential heat sink, making transmural lesions difficult to obtain. In this report, we summarize the use of nine different unidirectional devices (four radiofrequency, two microwave, two lasers, one cryothermic) for creating continuous transmural lines of ablation from the atrial epicardium in a porcine model. We define a unidirectional device as one in which all the energy is applied by a single transducer on a single heart surface. The maximum penetration of any device was 8.3 mm. All devices except one, the AtriCure Isolator pen, failed to penetrate 2 mm in some nontransmural sections. Future development of unidirectional energy sources should be directed at increasing the maximum depth and the consistency of penetration.
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Affiliation(s)
- Richard B Schuessler
- Barnes Jewish Hospital and Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA.
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Voeller RK, Aziz A, Maniar HS, Ufere NN, Taggar AK, Bernabe NJ, Cupps BP, Moon MR. Differential modulation of right ventricular strain and right atrial mechanics in mild vs. severe pressure overload. Am J Physiol Heart Circ Physiol 2011; 301:H2362-71. [PMID: 21926343 PMCID: PMC3233814 DOI: 10.1152/ajpheart.00138.2011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Accepted: 08/24/2011] [Indexed: 11/22/2022]
Abstract
Increased right atrial (RA) and ventricular (RV) chamber volumes are a late maladaptive response to chronic pulmonary hypertension. The purpose of the current investigation was to characterize the early compensatory changes that occur in the right heart during chronic RV pressure overload before the development of chamber dilation. Magnetic resonance imaging with radiofrequency tissue tagging was performed on dogs at baseline and after 10 wk of pulmonary artery banding to yield either mild RV pressure overload (36% rise in RV pressure; n = 5) or severe overload (250% rise in RV pressure; n = 4). The RV free wall was divided into three segments within a midventricular plane, and circumferential myocardial strain was calculated for each segment, the septum, and the left ventricle. Chamber volumes were calculated from stacked MRI images, and RA mechanics were characterized by calculating the RA reservoir, conduit, and pump contribution to RV filling. With mild RV overload, there were no changes in RV strain or RA function. With severe RV overload, RV circumferential strain diminished by 62% anterior (P = 0.04), 42% inferior (P = 0.03), and 50% in the septum (P = 0.02), with no change in the left ventricle (P = 0.12). RV filling became more dependent on RA conduit function, which increased from 30 ± 9 to 43 ± 13% (P = 0.01), than on RA reservoir function, which decreased from 47 ± 6 to 33 ± 4% (P = 0.04), with no change in RA pump function (P = 0.94). RA and RV volumes and RV ejection fraction were unchanged from baseline during either mild (P > 0.10) or severe RV pressure overload (P > 0.53). In response to severe RV pressure overload, RV myocardial strain is segmentally diminished and RV filling becomes more dependent on RA conduit rather than reservoir function. These compensatory mechanisms of the right heart occur early in chronic RV pressure overload before chamber dilation develops.
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MESH Headings
- Adaptation, Physiological
- Animals
- Atrial Function, Right
- Biomechanical Phenomena
- Blood Pressure
- Constriction
- Disease Models, Animal
- Dogs
- Familial Primary Pulmonary Hypertension
- Hypertension, Pulmonary/complications
- Hypertension, Pulmonary/physiopathology
- Hypertrophy, Right Ventricular/etiology
- Hypertrophy, Right Ventricular/physiopathology
- Magnetic Resonance Imaging
- Pulmonary Artery/physiopathology
- Pulmonary Artery/surgery
- Severity of Illness Index
- Stress, Mechanical
- Stroke Volume
- Time Factors
- Ventricular Dysfunction, Right/etiology
- Ventricular Dysfunction, Right/physiopathology
- Ventricular Function, Right
- Ventricular Pressure
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Affiliation(s)
- Rochus K Voeller
- Division of Cardiothoracic Surgery, Washington University School of Medicine, Saint Louis, Missouri, USA
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Voeller RK, Zierer A, Schuessler RB, Damiano RJ. Performance of a Novel Dual-Electrode Bipolar Radiofrequency Ablation Device a Chronic Porcine Study. Innovations 2011. [DOI: 10.1177/155698451100600104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Rochus K. Voeller
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St Louis, MO USA
| | - Andreas Zierer
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St Louis, MO USA
| | - Richard B. Schuessler
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St Louis, MO USA
| | - Ralph J. Damiano
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St Louis, MO USA
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Voeller RK, Melby SJ, Grizzell BE, Moazami N. Novel use of plasmapheresis in a patient with heparin-induced thrombocytopenia requiring urgent insertion of a left ventricular assist device under cardiopulmonary bypass. J Thorac Cardiovasc Surg 2010; 140:e56-8. [DOI: 10.1016/j.jtcvs.2010.06.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2009] [Revised: 02/24/2010] [Accepted: 06/09/2010] [Indexed: 01/25/2023]
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Voeller RK, Zierer A, Lall SC, Sakamoto SI, Schuessler RB, Damiano RJ. Efficacy of a novel bipolar radiofrequency ablation device on the beating heart for atrial fibrillation ablation: a long-term porcine study. J Thorac Cardiovasc Surg 2010; 140:203-8. [PMID: 20122702 DOI: 10.1016/j.jtcvs.2009.06.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 05/16/2009] [Accepted: 06/08/2009] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Over recent years, a variety of energy sources have been used to replace the traditional incisions of the Cox maze procedure for the surgical treatment of atrial fibrillation. This study evaluated the safety and efficacy of a new bipolar radiofrequency ablation device for atrial ablation in a long-term porcine model. METHODS Six pigs underwent a Cox maze IV procedure on a beating heart off cardiopulmonary bypass using the AtriCure Isolator II bipolar ablation device (AtriCure, Inc, Cincinnati, Ohio). In addition, 6 pigs underwent median sternotomy and pericardiotomy alone to serve as a control group. All animals were allowed to survive for 30 days. Each pig underwent induction of atrial fibrillation and was then humanely killed to remove the heart en bloc for histologic assessment. Magnetic resonance imaging scans were also obtained preoperatively and postoperatively to assess atrial and ventricular function, pulmonary vein anatomy, valve function, and coronary artery patency. RESULTS All animals survived the operation. Electrical isolation of the left atrial appendage and the pulmonary veins was documented by pacing acutely and at 30 days in all animals. No animal that underwent the Cox maze IV procedure was able to be induced into atrial fibrillation at 30 days postoperatively, compared with all the sham animals. All 257 ablations examined were discrete, linear, and transmural, with a mean lesion width of 2.2 +/- 1.1 mm and a mean lesion depth of 5.3 +/- 3.0 mm. CONCLUSIONS The AtriCure Isolator II device was able to create reliable long-term transmural lesions of the modified Cox maze procedure on a beating heart without cardiopulmonary bypass 100% of the time. There were no discernible effects on ventricular or valvular function.
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Affiliation(s)
- Rochus K Voeller
- Division of Cardiothoracic Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St Louis, MO 63110, USA
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Zierer A, Melby SJ, Voeller RK, Moon MR. Interatrial shunt for chronic pulmonary hypertension: differential impact of low-flow vs. high-flow shunting. Am J Physiol Heart Circ Physiol 2009; 296:H639-44. [PMID: 19136607 DOI: 10.1152/ajpheart.00496.2008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purpose of the present study was to determine for the first time the qualitative and quantitative impact of varying degrees of interatrial shunting on right heart dynamics and systemic perfusion in subjects with chronic pulmonary hypertension (CPH). Eight dogs underwent 3 mo of progressive pulmonary artery banding, following which right atrial and ventricular end-systolic and end-diastolic pressure-volume relations were calculated using conductance catheters. An 8-mm shunt prosthesis was inserted between the superior vena cava and left atrium, yielding a controlled model of atrial septostomy. Data were obtained 1) preshunt or "CPH"; 2) "Low-Flow" shunt; and 3) "High-Flow" shunt (occluding superior vena cava forcing all flow through the shunt). With progressive shunting, right ventricular pressure fell from 72 +/- 19 mmHg (CPH) to 54 +/- 17 mmHg (Low-Flow) and 47 +/- 17 mmHg (High-Flow) (P < 0.001). Cardiac output increased from 1.5 +/- 0.3 l/min at CPH to 1.8 +/- 0.4 l/min at Low-Flow (286 +/- 105 ml/min, 15% of cardiac output; P < 0.001), but returned to 1.6 +/- 0.3 l/min at High-Flow (466 +/- 172 ml/min, 29% of cardiac output; P = 0.008 vs. Low-Flow, P = 0.21 vs. CPH). There was a modest rise in systemic oxygen delivery from 252 +/- 46 ml/min at CPH to 276 +/- 50 ml/min at Low-Flow (P = 0.07), but substantial fall to 222 +/- 50 ml/min at High-Flow (P = 0.005 vs. CPH, P < 0.001 vs. Low-Flow). With progressive shunting, bichamber contractility did not change (P = 0.98), but the slope of the right atrial end-diastolic pressure volume relation decreased (P < 0.04), consistent with improved compliance. This study demonstrated that Low-Flow interatrial shunting consistently improved right atrial mechanics and systemic perfusion in subjects with CPH, while High-Flow exceeded an "ideal shunt fraction".
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Affiliation(s)
- Andreas Zierer
- Division of Cardiothoracic Surgery, Washington Univ. School of Medicine, 3108 Queeny Tower, #1 Barnes-Jewish Plaza, St. Louis, Missouri 63110-1013, USA
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Sakamoto SI, Voeller RK, Melby SJ, Lall SC, Chang NL, Schuessler RB, Damiano RJ. Surgical ablation for atrial fibrillation: the efficacy of a novel bipolar pen device in the cardioplegically arrested and beating heart. J Thorac Cardiovasc Surg 2008; 136:1295-301. [PMID: 19026819 DOI: 10.1016/j.jtcvs.2008.04.030] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Revised: 03/18/2008] [Accepted: 04/03/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVE The introduction of ablation technology has simplified surgical intervention for atrial fibrillation. However, most ablation devices cannot create focal transmural lesions on the beating heart and have difficulty ablating specific regions of the atria, such as the atrioventricular isthmus, coronary sinus, and ganglionated plexus. The purpose of this study was to examine the efficacy of a pen-type bipolar radiofrequency ablation device on both arrested and beating hearts. METHODS Endocardial and epicardial atrial tissues in the free wall, left atrial roof, atrioventricular annuli, and coronary sinus were ablated for varying time intervals (2.5-15 seconds) in porcine cardioplegically arrested (n = 6) and beating (n = 9) hearts. The hearts were stained with 1% 2,3,5-triphenyl-tetrazolium chloride solution and sectioned to determine lesion depth and width. In 5 animals epicardial fat pads containing ganglionated plexus were stimulated and ablated. RESULTS Lesion depth increased with ablation time similarly in both arrested and beating hearts. Transmurality was fully achieved in the thin atrial tissue (<4 mm) at 10 seconds in the beating and arrested hearts. The device had a maximal penetration depth of 6.1 mm. Epicardial ablation of the coronary sinus showed complete penetration through the left posterior atrium only in the arrested heart. Seven of 17 fat pads demonstrated a vagal response. All vagal responses were eliminated after ablation. CONCLUSION The bipolar pen effectively ablated atrial tissue in both arrested and beating hearts. This device might allow the surgeon to ablate tissue in regions not accessible to other devices during atrial fibrillation surgery.
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Affiliation(s)
- Shun-ichiro Sakamoto
- Division of Cardiothoracic Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, MO 63110, USA
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Voeller RK, Zierer A, Lall SC, Sakamoto SI, Chang NL, Schuessler RB, Moon MR, Damiano RJ. The effects of the Cox maze procedure on atrial function. J Thorac Cardiovasc Surg 2008; 136:1257-64, 1264.e1-3. [PMID: 19026812 DOI: 10.1016/j.jtcvs.2008.01.053] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2007] [Accepted: 01/24/2008] [Indexed: 11/28/2022]
Abstract
OBJECTIVE The effects of the Cox maze procedure on atrial function remain poorly defined. The purpose of this study was to investigate the effects of a modified Cox maze procedure on left and right atrial function in a porcine model. METHODS After cardiac magnetic resonance imaging, 6 pigs underwent pericardiotomy (sham group), and 6 pigs underwent a modified Cox maze procedure (maze group) with bipolar radiofrequency ablation. The maze group had preablation and immediate postablation left and right atrial pressure-volume relations measured with conductance catheters. All pigs survived for 30 days. Magnetic resonance imaging was then repeated for both groups, and conductance catheter measurements were repeated for the right atrium in the maze group. RESULTS Both groups had significantly higher left atrial volumes postoperatively. Magnetic resonance imaging-derived reservoir and booster pump functional parameters were reduced postoperatively for both groups, but there was no difference in these parameters between the groups. The maze group had significantly higher reduction in the medial and lateral left atrial wall contraction postoperatively. There was no change in immediate left atrial elastance or in the early and 30-day right atrial elastance after the Cox maze procedure. Although the initial left atrial stiffness increased after ablation, right atrial diastolic stiffness did not change initially or at 30 days. CONCLUSIONS Performing a pericardiotomy alone had a significant effect on atrial function that can be quantified by means of magnetic resonance imaging. The effects of the Cox maze procedure on left atrial function could only be detected by analyzing segmental wall motion. Understanding the precise physiologic effects of the Cox maze procedure on atrial function will help in developing less-damaging lesion sets for the surgical treatment of atrial fibrillation.
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Affiliation(s)
- Rochus K Voeller
- Division of Cardiothoracic Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St Louis, MO 63110, USA
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Voeller RK, Bailey MS, Zierer A, Lall SC, Sakamoto SI, Aubuchon K, Lawton JS, Moazami N, Huddleston CB, Munfakh NA, Moon MR, Schuessler RB, Damiano RJ. Isolating the entire posterior left atrium improves surgical outcomes after the Cox maze procedure. J Thorac Cardiovasc Surg 2008; 135:870-7. [DOI: 10.1016/j.jtcvs.2007.10.063] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Revised: 09/12/2007] [Accepted: 10/26/2007] [Indexed: 11/30/2022]
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Lall SC, Foyil KV, Sakamoto SI, Voeller RK, Boineau JP, Damiano RJ, Schuessler RB. Pulmonary vein isolation and the Cox maze procedure only partially denervate the atrium. J Thorac Cardiovasc Surg 2008; 135:894-900. [PMID: 18374777 DOI: 10.1016/j.jtcvs.2007.11.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2007] [Revised: 09/20/2007] [Accepted: 11/26/2007] [Indexed: 10/22/2022]
Abstract
OBJECTIVES The effects of ablation lines on myocardial innervation and response to autonomic stimuli are unclear. This study examined the effects of radiofrequency ablation on atrial autonomic innervation and compared pulmonary vein isolation and the biatrial Cox maze procedure. METHODS In 12 acute canines right and left vagosympathetic trunks and right and left stellate ganglia were isolated. Each nerve was stimulated before bipolar ablation, after pulmonary vein isolation, and after the Cox maze procedure. Nadolol (n = 6) and atropine (n = 6) were administered to block sympathetic and parasympathetic responses, respectively. Changes in heart rate and atrioventricular interval were compared. Changes in QRST area relative to an isoelectric baseline (index of local innervation) were calculated. RESULTS Sympathetic stimulation of each nerve and parasympathetic stimulation of the vagosympathetic trunks caused significant changes in heart rate and atrioventricular interval. After pulmonary vein isolation, the effect of 33% of the nerves on heart rate changes was eliminated. The Cox maze procedure eliminated right stellate sympathetic effects on heart rate. Fifty percent of the nerves caused heart rate changes after the Cox maze procedure. There was no significant effect of either lesion set on atrioventricular interval changes. Stimulation of 50% of nerves after pulmonary vein isolation produced local area changes significantly different from control area. After the Cox maze procedure, a different 50% of the nerves produced local changes different from those seen after pulmonary vein isolation. CONCLUSIONS Surgical ablation procedures disrupted innervation, affecting heart rate but not atrioventricular interval. Autonomic innervation affecting the atria was changed by pulmonary vein isolation and additionally by the Cox maze procedure. Residual autonomic effects were present even after the complete Cox maze procedure.
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Affiliation(s)
- Shelly C Lall
- Division of Cardiothoracic Surgery, Washington University School of Medicine, Saint Louis, MO 63110, USA
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Zierer A, Melby SJ, Voeller RK, Steendijk P, Moon MR. INTERATRIAL SHUNT FOR CHRONIC PULMONARY HYPERTENSION: DIFFERENTIAL IMPACT OF LOW-FLOW VS HIGH-FLOW SHUNTING. Chest 2007. [DOI: 10.1378/chest.132.4_meetingabstracts.487b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Al-Dadah AS, Voeller RK, Schuessler RB, Damiano RJ, Lawton JS. Maintenance of myocyte volume homeostasis during stress by diazoxide is cardioprotective. Ann Thorac Surg 2007; 84:857-62. [PMID: 17720390 DOI: 10.1016/j.athoracsur.2007.04.103] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2007] [Revised: 04/20/2007] [Accepted: 04/24/2007] [Indexed: 11/16/2022]
Abstract
BACKGROUND We previously demonstrated that myocyte swelling and reduced contractility secondary to hyperkalemic cardioplegia and hyposmotic stress are attenuated by the addition of diazoxide, an adenosine triphosphate-sensitive potassium channel (K(ATP)) opener. The goal of this study was to investigate the effect of diazoxide on myocyte swelling and reduced contractility after metabolic inhibition and to attempt to summarize the potential mechanisms involved. METHODS Isolated rabbit myocytes were perfused with Tyrode's control solution for 20 minutes, followed by test solution for 20 minutes. Test solutions included (1) Tyrode's control, (2) a metabolic inhibition solution containing sodium cyanide and 2-deoxyglucose, (3) metabolic inhibition plus diazoxide, (4) metabolic inhibition plus diazoxide plus HMR1098 (a sarcolemmal K(ATP)-channel blocker), or (5) metabolic inhibition plus diazoxide plus 5-hydroxydeconoate (a mitochondrial K(ATP)-channel blocker). Myocytes were then reexposed to Tyrode's solution for 20 minutes. Volume measurements were taken every 5 minutes. Contractility was recorded using edge-detection software at baseline and at 10 and 20 minutes of reexposure to Tyrode's solution. RESULTS Simulated ischemia (metabolic inhibition) caused significant myocyte swelling and associated reduced contractility. The addition of diazoxide abolished myocyte swelling and attenuated the associated reduced contractility. Observations with diazoxide were unchanged by the addition of HMR 1098 or 5-hydroxydeconoate. CONCLUSIONS Diazoxide, with or without either K(ATP)-channel blocker, attenuated the significant myocyte swelling and reduced contractility secondary to metabolic inhibition. These data suggest a role for diazoxide, independent of the K(ATP) channel, in myocyte volume homeostasis. In addition, the prevention of myocyte swelling resulted in improved contractility, consistent with previous data and the hypothesis that myocyte swelling may participate in the phenomenon of myocardial stunning.
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Affiliation(s)
- Ashraf S Al-Dadah
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Zierer A, Melby SJ, Voeller RK, Guthrie TJ, Ewald GA, Shelton K, Pasque MK, Moon MR, Damiano RJ, Moazami N. Late-Onset Driveline Infections: The Achilles’ Heel of Prolonged Left Ventricular Assist Device Support. Ann Thorac Surg 2007; 84:515-20. [PMID: 17643627 DOI: 10.1016/j.athoracsur.2007.03.085] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Revised: 03/24/2007] [Accepted: 03/27/2007] [Indexed: 10/23/2022]
Abstract
BACKGROUND A successful left ventricular assist device (LVAD) long-term support in an outpatient setting demands that device-related complications are reduced to a minimum. We hypothesized that late onset driveline infections have serious implications on the anticipated application of LVAD as permanent therapy. METHODS Between 1996 and 2005, 73 patients were implanted with the Novacor (World Heart Corp, Ottawa, Ontario, Canada; n = 35) or the HeartMate (Thoratec Corp, Pleasanton, CA; n = 38) as either bridge to transplantation (n = 44) or destination therapy (n = 29). Our analysis focused on patients with late-onset infection (> or = 30 days) of the driveline exit site with prior clinical healing of all incisions. RESULTS Late driveline infections developed in 17 patients (23%) at a median of 158 days (intraquartile range [IQR]: 68 to 213 days) after implantation. The median duration of support in this subgroup was 400 days (IQR, 283 to 849 days). Despite an aggressive treatment algorithm, repeat surgical revision was needed in 12 patients, up to six times in 2 individuals. In 6 patients, the infection progressed to pump pocket infections that led to urgent heart transplantation (n = 4) or explantation (n = 2). The individual risk that a driveline infection would develop dramatically increased with the duration of support, reaching 94% at 1 year. Multivariate analysis identified duration of support (p < 0.001) and documented trauma at the driveline exit site (p < 0.001) as independent predictors of infection. Number and duration of readmissions to the hospital significantly increased (p < 0.001), and long-term follow-up for survival (4.4 +/- 2.2 years, 100% complete) showed a trend towards impaired outcome after driveline infection (5-year survival: 41% versus 70%, p = 0.10). CONCLUSIONS Long-term LVAD support in the current series was jeopardized by late-onset driveline infections, which occurred in all patients with support duration longer than 1 year. Once driveline infections developed, they were difficult to control and significantly increased morbidity.
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Affiliation(s)
- Andreas Zierer
- Division of Cardiothoracic Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri 62236, USA
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Zierer A, Voeller RK, Hill KE, Kouchoukos NT, Damiano RJ, Moon MR. Aortic Enlargement and Late Reoperation After Repair of Acute Type A Aortic Dissection. Ann Thorac Surg 2007; 84:479-86; discussion 486-7. [PMID: 17643619 DOI: 10.1016/j.athoracsur.2007.03.084] [Citation(s) in RCA: 200] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Revised: 03/26/2007] [Accepted: 03/27/2007] [Indexed: 10/23/2022]
Abstract
BACKGROUND The natural history of the residual aorta after repair of acute type A aortic dissection is incompletely understood. METHODS During a 22-year period, 201 patients underwent repair of acute type A dissection by 25 surgeons. For 168 operative survivors, mean late follow-up for reoperation or death was 6.5 +/- 5.5 years and was 100% complete. Late blood pressure and medication history were available for 136 patients. Overall, 412 computed tomography scans were analyzed for segmental diameter and false lumen patency from 69 patients who underwent multiple follow-up imaging studies at our institution. RESULTS Freedom from reoperation at 10 years (range, 1 to 170 months) was 74% +/- 5% (28 reoperations in 26 patients). A nonresected primary tear (p = 0.05), Marfan syndrome (p < 0. 001), elevated systolic blood pressure at follow-up (p = 0.008), and absence of beta-blocker therapy (p = 0.02) were independent predictors of late reoperation. Aortic growth between consecutive imaging studies was detected in 18% of intervals (62/343) affecting 49% patients (34/69), with mean yearly growth rate of 5.3 +/- 4.5 mm. Onset of enlargement was unpredictable and occurred 59 +/- 45 months postoperatively (range, 1 to 167 months). Risk factors for growth included aortic diameter (p < 0. 001), elevated systolic blood pressure (p = 0.04), and presence of a patent false lumen (p = 0.05). Maximum aortic diameter of less than 35 mm predicted growth in 11% of intervals, 35 to 49 mm in 22%, and more than 49 mm in 37% (p < 0.001). Different proximal or distal surgical strategies did not affect aortic growth or need for reoperation (p > 0.17). CONCLUSIONS Optimal long-term outcome of patients with acute type A dissection demands rigorous antihypertensive therapy and lifelong radiographic follow-up because aortic enlargement can begin more than a decade postoperatively.
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Affiliation(s)
- Andreas Zierer
- Division of Cardiothoracic Surgery, The Center for Diseases of the Thoracic Aorta, Washington University School of Medicine, Barnes Jewish Hospital, St. Louis, Missouri 63110-1013, USA
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Zierer A, Melby SJ, Voeller RK, Guthrie TJ, Al-Dadah AS, Meyers BF, Pasque MK, Ewald GA, Moon MR, Moazami N. Significance of Neurologic Complications in the Modern Era of Cardiac Transplantation. Ann Thorac Surg 2007; 83:1684-90. [PMID: 17462379 DOI: 10.1016/j.athoracsur.2006.12.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2006] [Revised: 12/06/2006] [Accepted: 12/11/2006] [Indexed: 10/23/2022]
Abstract
BACKGROUND Severe neurologic complications after cardiac transplantation are devastating outcomes of this life-saving procedure. Incidence, risk factors, and morbidity of neurologic events in the modern era of cardiac transplantation are yet to be defined. METHODS Between 1996 and 2005, 200 patients (64% men; mean age, 49 +/- 12 years) underwent heart transplantation at our institution. Overall, 46 patients (23%) showed a wide spectra of early neurologic complications. RESULTS Cause of ischemic complications was stroke in 11 patients (7 had concomitant epileptic seizures) and transient ischemic attack (TIA) in 7. Encephalopathy (n = 10), epileptic seizures unrelated to focal cerebral lesions (n = 7), severe headache (n = 6), cerebral infection (n = 3), and peripheral nervous system injuries (n = 2) completed the spectra of adverse neurologic outcomes. Multivariate analysis identified advanced age (p = 0.03), preoperative left ventricular assist device support (p = 0.02), preoperative intraaortic balloon pump support (p < 0.001), prolonged cardiopulmonary bypass time (p < 0.001), and postoperative hepatic failure (p = 0.04) as independent predictors of early neurologic complications. Postoperative morbidities associated with neurologic complications included longer ventilation time (p < 0.001), longer stay in the intensive care unit (p < 0.001), and higher incidence of pneumonia (p < 0.001) and sepsis (p = 0.01) compared with patients without neurologic events. There was a trend toward higher in-hospital mortality (15% versus 6%, p = 0.07), but there was no difference in long-term survival (65% versus 78%, p = 0.15). CONCLUSIONS Despite rigorous pretransplantation screening, neurologic complications were common after cardiac transplantation. Most frequently, these complications were not the actual cause of death, but they significantly contributed to increased morbidity. Preoperative mechanical circulatory support requirement was the strongest predictor for adverse neurologic outcome.
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Affiliation(s)
- Andreas Zierer
- Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, Missouri 62236, USA
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Zierer A, Voeller RK, Melby SJ, Kawa CB, Guthrie TJ, Baumgartner M, Pasque MK, Moon MR, Moazami N. Potential renal protective benefits of intra-operative BNP infusion during cardiac transplantation. Transplant Proc 2007; 38:3680-4. [PMID: 17175366 DOI: 10.1016/j.transproceed.2006.10.177] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2006] [Indexed: 11/19/2022]
Abstract
BACKGROUND Recombinant BNP (nesiritide) is known to reduce endothelin levels, cause afferent arteriole vasodilation, and increase natriuresis and diuresis. We hypothesized that intraoperative infusion of BNP may benefit renal function in cardiac transplant patients. METHODS From June 2003 to September 2005, 22 consecutive heart transplant patients received BNP at a dose of 0.01 microg/kg/min before initiation of cardiopulmonary bypass (group A). BNP infusion was continued for a mean of 3.3 +/- 1.9 days. Hemodynamics, urine output, and serum creatinine levels were prospectively collected and compared with 22 consecutive patients who underwent heart transplantation between May 2002 and June 2003 following the identical transplant protocol, but without BNP infusion (group B). RESULTS At 24 hours postoperatively, mean blood pressure was comparable between groups (87 +/- 11 mm Hg vs 89 +/- 17 mm Hg, P = .7), but pulmonary artery pressure (18 +/- 5 mm Hg vs 24 +/- 5 mm Hg, P = .001) and central venous pressure (12 +/- 5 mm Hg vs 16 +/- 4 mm Hg, P = .01) were lower with BNP infusion, whereas cardiac index was augmented (2.8 +/- 0.5 vs 2.4 +/- 0.6, P = .03). Requirement of low-dose inotropic and vasopressor support was equally distributed between groups (P > or = .72). Postoperative urine output for the initial 24 hours was higher in group A (84 +/- 15 vs 55 +/- 36 mL/h, P = .01). None of the patients with BNP infusion required additional diuretics or renal replacement therapy during the first week after transplantation. Mean postoperative serum creatinine levels as compared with preoperative values remained unchanged within group A (P = .12), but increased significantly in group B (P < .001). CONCLUSIONS Intraoperative BNP infusion in heart transplant recipients was associated with favorable postoperative hemodynamics, significantly improved urine output, and stable serum creatinine levels. A prospective, randomized, multicenter trial is warranted to evaluate the potential renal protective benefits of intraoperative BNP infusion in this patient population.
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Affiliation(s)
- A Zierer
- Division of Cardiovascular Surgery, Washington University School of Medicine, Barnes Jewish Hospital, Saint Louis, Missouri 62236, USA
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Abstract
The surgical treatment of atrial fibrillation began in 1987, when Dr. James Cox introduced the maze procedure. This operation proved to be extremely effective in curing atrial fibrillation and preventing its most dreaded complication, stroke. However, many surgeons found the operation to be too difficult and invasive. Over the last 5 to 10 years, various groups have tried to develop less invasive approaches using a number of different energy sources to create linear lines of ablation to replace the surgical incisions. This has led to a plethora of new operations for this arrhythmia. There is significant confusion in the literature at the present time as to what is the best lesion pattern and what is the best energy source. It is our feeling that a great deal of this confusion is due to our lack of understanding of the mechanisms of atrial fibrillation and the effect of ablation technology on atrial hemodynamics and electrophysiology. Future progress will require a better understanding of this arrhythmia and continued research into the safety and efficacy of ablation devices.
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Affiliation(s)
- Ralph J Damiano
- Department of Surgery, Barnes-Jewish Hospital, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
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Melby SJ, Zierer A, Voeller RK, Lall SC, Bailey MS, Moon MR, Schuessler RB, Damiano RJ. Wide Variations in Energy Delivery Using an Impedance-Controlled Algorithm in Bipolar Radiofrequency Ablation: Evidence against Fixed Time Ablation. Innovations 2007. [DOI: 10.1177/155698450700200204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Spencer J. Melby
- Washington University School of Medicine and Barnes-Jewish Hospital, Division of Cardiothoracic Surgery, Department of Surgery, St. Louis, MO
| | - Andreas Zierer
- Washington University School of Medicine and Barnes-Jewish Hospital, Division of Cardiothoracic Surgery, Department of Surgery, St. Louis, MO
| | - Rochus K. Voeller
- Washington University School of Medicine and Barnes-Jewish Hospital, Division of Cardiothoracic Surgery, Department of Surgery, St. Louis, MO
| | - Shelly C. Lall
- Washington University School of Medicine and Barnes-Jewish Hospital, Division of Cardiothoracic Surgery, Department of Surgery, St. Louis, MO
| | - Marci S. Bailey
- Washington University School of Medicine and Barnes-Jewish Hospital, Division of Cardiothoracic Surgery, Department of Surgery, St. Louis, MO
| | - Marc R. Moon
- Washington University School of Medicine and Barnes-Jewish Hospital, Division of Cardiothoracic Surgery, Department of Surgery, St. Louis, MO
| | - Richard B. Schuessler
- Washington University School of Medicine and Barnes-Jewish Hospital, Division of Cardiothoracic Surgery, Department of Surgery, St. Louis, MO
| | - Ralph J. Damiano
- Washington University School of Medicine and Barnes-Jewish Hospital, Division of Cardiothoracic Surgery, Department of Surgery, St. Louis, MO
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Lall SC, Melby SJ, Voeller RK, Zierer A, Bailey MS, Guthrie TJ, Moon MR, Moazami N, Lawton JS, Damiano RJ. The effect of ablation technology on surgical outcomes after the Cox-maze procedure: A propensity analysis. J Thorac Cardiovasc Surg 2007; 133:389-96. [PMID: 17258570 DOI: 10.1016/j.jtcvs.2006.10.009] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2006] [Revised: 09/22/2006] [Accepted: 10/09/2006] [Indexed: 11/20/2022]
Abstract
OBJECTIVES Since its introduction in 1987, the Cox-maze procedure has been the gold standard for the surgical treatment of atrial fibrillation. At our institution, this procedure has evolved from the cut-and-sew technique (Cox-maze III procedure) to one using bipolar radiofrequency energy and cryoablation as ablative sources to replace most incisions (Cox-maze IV procedure). This study compared surgical outcomes of patients undergoing the Cox-maze III procedure versus those of patients undergoing the Cox-maze IV procedure by using propensity analysis. METHODS From April 1992 through July 2005, 242 patients underwent the Cox-maze procedure for atrial fibrillation. Of these, 154 patients had the Cox-maze III procedure, and 88 had the Cox-maze IV procedure. Logistic regression analysis was used to identify covariates among 7 baseline patient variables. Using the significant regression coefficients, each patient's propensity score was calculated, allowing selectively matched subgroups of 58 patients each. Operative outcomes were analyzed for differences. Late follow-up was available for 112 (97%) patients. Freedom from atrial fibrillation recurrence and survival was calculated at 1 year by using Kaplan-Meier analysis. RESULTS The Cox-maze III procedure had significantly longer crossclamp times. There was no significant difference in intensive care unit and hospital stay, 30-day mortality, permanent pacemaker placement, early atrial tachyarrhythmias, late stroke, and survival. Freedom from atrial fibrillation recurrence was greater than 90% in both groups at 1 year. CONCLUSIONS The use of bipolar radiofrequency ablation has simplified the Cox-maze procedure, making it applicable to virtually all patients with atrial fibrillation undergoing concomitant cardiac surgery. The Cox-maze IV procedure produces similar surgical outcomes to the Cox-maze III procedure at 1 year of follow-up.
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Affiliation(s)
- Shelly C Lall
- Division of Cardiothoracic Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, Saint Louis, Mo 63110, USA
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Al-Dadah AS, Voeller RK, Rahgozar P, Lawton JS, Moon MR, Pasque MK, Damiano RJ, Moazami N. Implantable cardioverter-defibrillators improve survival after coronary artery bypass grafting in patients with severely impaired left ventricular function. J Cardiothorac Surg 2007; 2:6. [PMID: 17222353 PMCID: PMC1785373 DOI: 10.1186/1749-8090-2-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2006] [Accepted: 01/12/2007] [Indexed: 12/02/2022] Open
Abstract
Objective Patients with severe left ventricular (LV) dysfunction have a poor long term survival despite complete surgical revascularization. Recent data suggests that the use of Implantable Cardioverter-Defibrillator (ICD) improves survival in patients with severe LV dysfunction. We compared the survival impact of ICD implantation in patients with severe LV dysfunction who underwent CABG. Methods Between January 1996 and August 2004, 305 patients with LV ejection fraction (EF) ≤25% had CABG surgery at our institution. Demographics of patients who had received an ICD (ICD+) in the post -operative period was compared to those without ICD (ICD-). Survival was evaluated by the Kaplan-Meier method. Results Of the entire group, 35 (11.5%) patients received an ICD with a median of 2 (+/-2) years after CABG. Indication for ICD implantation was clinical evidence of non sustained ventricular tachycardia (NSVT). There were no differences between the 2 groups with respect to age, gender, NYHA classification, number of bypasses, or other co-morbidities. Survival at 1, 3 and 5 years was 88%, 79%, and 67% for the ICD- group compared to 94%, 89% and 83% for the ICD+ group, respectively (figure, p < 0.05). Conclusion Implantation of ICD after CABG confers improved short and long term survival benefit to patients with severe LV dysfunction. Prophylactic ICD implantation in the setting of severe LV dysfunction and CABG surgery should be considered.
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Affiliation(s)
- Ashraf S Al-Dadah
- Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine in St Louis, St Louis, USA
| | - Rochus K Voeller
- Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine in St Louis, St Louis, USA
| | - Paymon Rahgozar
- Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine in St Louis, St Louis, USA
| | - Jennifer S Lawton
- Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine in St Louis, St Louis, USA
| | - Marc R Moon
- Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine in St Louis, St Louis, USA
| | - Michael K Pasque
- Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine in St Louis, St Louis, USA
| | - Ralph J Damiano
- Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine in St Louis, St Louis, USA
| | - Nader Moazami
- Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine in St Louis, St Louis, USA
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Damiano Jr RJ, Schuessler RB, Voeller RK. Future Directions in Atrial Fibrillation Surgery. J Arrhythm 2007. [DOI: 10.4020/jhrs.23.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Damiano RJ, Schuessler RB, Voeller RK. Future Directions in Atrial Fibrillation Surgery. J Arrhythm 2007. [DOI: 10.1016/s1880-4276(07)80011-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Melby SJ, Kaiser SP, Bailey MS, Zierer A, Voeller RK, Lall SC, Munfakh N, Moon MR, Damiano RJ. Surgical treatment of atrial fibrillation with bipolar radiofrequency ablation: mid-term results in one hundred consecutive patients. J Cardiovasc Surg (Torino) 2006; 47:705-10. [PMID: 17043619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
AIM The Cox-Maze procedure was introduced nearly two decades ago for the surgical treatment of atrial fibrillation (AF). Recently, our group has replaced most of the incisions of the Cox-Maze procedure with bipolar radiofrequency (RF) ablations (Cox-Maze IV procedure). The purpose of this study was to examine our midterm results with the Cox-Maze procedure using bipolar RF ablation. METHODS From January 2002 to October 2005, 100 consecutive patients underwent a modified Cox-Maze procedure with bipolar RF ablation for AF; 32 were lone operations, and 68 were concomitant procedures. Follow-up was performed at 1, 3, 6, and 12 months, and then annually thereafter. Heart rhythm was confirmed by electrocardiography. RESULTS The mean age of patients was 62+/-13 years; 57% were male. Duration of AF was 6.3+/-7.6 years (0.1 to 40 years), 59% had paroxysmal AF, and 34% had permanent AF. Follow-up was complete for all patients with a mean follow-up of 13+/-10 months. At 12-month follow-up, 91% (49/54) of patients were free of AF. Cross-clamp time in the lone Cox-Maze IV procedure patients was 42+/-15 minutes, while it was 101+/-29 minutes for the Cox-Maze IV with a concomitant procedure (compared to 93+/-34 minutes and 122+/-37 minutes for the traditional procedure, P<0.05). There were four operative deaths. CONCLUSIONS The Cox-Maze IV procedure had good mid-term efficacy. The use of bipolar RF energy significantly decreased operative time and simplified the procedure compared to the traditional Cox-Maze procedure, potentially increasing utilization of the procedure among cardiac surgeons.
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Affiliation(s)
- S J Melby
- Washington University School of Medicine/Barnes Jewish Hospital, St. Louis, MO 63110, USA
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Abstract
The Cox-Maze procedure, first introduced in 1987, has been the gold standard for the surgical treatment of atrial fibrillation. At 10 years, over 90% of patients remain free from atrial fibrillation. The procedure has been shown to be effective at eliminating the incidence of late stroke in this high-risk population. The development of new ablation technologies has greatly simplified and shortened the Cox-Maze procedure without sacrificing efficacy. These technologies have spurred interest in the development of new, simpler operations for the surgical treatment of atrial fibrillation that can be performed through minimal access and, in some instances, off of cardiopulmonary bypass. The early results with these more limited procedures on the whole have not been as good as with the Cox-Maze procedure, but they are promising. There are many problems with the development of a truly minimally invasive procedure with high efficacy. When patients are referred for surgery, there is no information available regarding the mechanisms of their atrial fibrillation. Thus, it is impossible to tailor the ablation to the individual patient. Future progress will require better understanding of the mechanisms of atrial fibrillation, and the development and refinement of clinical diagnostic technology that will allow for better preoperative diagnosis.
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Affiliation(s)
- Ralph J Damiano
- Cardiothoracic Surgery, Washington University School of Medicine, Campus Box 8234, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
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Peterson AJ, Mallin DR, Francis NJ, Ketel CS, Stamm J, Voeller RK, Kingston RE, Simon JA. Requirement for sex comb on midleg protein interactions in Drosophila polycomb group repression. Genetics 2005; 167:1225-39. [PMID: 15280237 PMCID: PMC1470928 DOI: 10.1534/genetics.104.027474] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Drosophila Sex Comb on Midleg (SCM) protein is a transcriptional repressor of the Polycomb group (PcG). Although genetic studies establish SCM as a crucial PcG member, its molecular role is not known. To investigate how SCM might link to PcG complexes, we analyzed the in vivo role of a conserved protein interaction module, the SPM domain. This domain is found in SCM and in another PcG protein, Polyhomeotic (PH), which is a core component of Polycomb repressive complex 1 (PRC1). SCM-PH interactions in vitro are mediated by their respective SPM domains. Yeast two-hybrid and in vitro binding assays were used to isolate and characterize >30 missense mutations in the SPM domain of SCM. Genetic rescue assays showed that SCM repressor function in vivo is disrupted by mutations that impair SPM domain interactions in vitro. Furthermore, overexpression of an isolated, wild-type SPM domain produced PcG loss-of-function phenotypes in flies. Coassembly of SCM with a reconstituted PRC1 core complex shows that SCM can partner with PRC1. However, gel filtration chromatography showed that the bulk of SCM is biochemically separable from PH in embryo nuclear extracts. These results suggest that SCM, although not a core component of PRC1, interacts and functions with PRC1 in gene silencing.
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Affiliation(s)
- Aidan J Peterson
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Abstract
RATIONALE There are increasing reports of sex differences in the etiology of drug abuse in humans. A nonhuman primate model is useful for examining sex as a variable in drug abuse. OBJECTIVES To determine whether there are sex differences in the acquisition of oral phencyclidine (PCP) self-administration and to compare the effect of altered feeding conditions on drug self-administration in male and female monkeys. METHODS Acquisition of orally delivered PCP was studied using 7 female and 11 male adult rhesus monkeys. Initially, the monkeys were not food restricted, and they were given access to water under concurrent fixed-ratio (FR) 1 schedules during daily 3-h sessions. Each lip-contact response on a drinking spout resulted in a 0.3 ml liquid delivery. After baseline levels of water intake were obtained for 5 days, water was replaced with PCP (0.125 mg/ml) at both drinking spouts. Body weights were then reduced to 85% of free-feeding weights, and the monkeys were fed 30 min before the session began. The FR value was increased from 1 to 2, 4, and 8, at both drinking spouts. As a final step in the procedure, water and PCP were concurrently available at the two spouts under FR 8 schedules. Acquisition of PCP-reinforced behavior was considered to have occurred if PCP intake was consistently greater than water intake. RESULTS Lip-contact responses and liquid deliveries were not significantly different between the females and males throughout the acquisition period, but there was a significant increase in responding and decrease in liquid intake as FR increased, and a significant increase in PCP consumption due to food restriction that did not differ in males and females. On a milligram per kilogram basis, female monkeys consumed nearly twice as much PCP as the males; however, this effect was not significant. The females showed significantly higher PCP than water intake while the males consumed approximately equal amounts of PCP and water. Of the seven females, 100% met the acquisition criterion of significantly greater PCP than water intake, while only 36.4% of the males met the criterion. CONCLUSION These results concur with previous rat studies and indicate that female monkeys are more likely than males to acquire drug-reinforced behavior.
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Affiliation(s)
- M E Carroll
- Department of Psychiatry, University of Minnesota Medical School, Minneapolis 55455-0392, USA
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