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Książek AA, Mitchell KJ, Morax L, Schwarzwald CC, Hoerstrup SP, Weber B. Hemodynamic Assessment of a Murine Heterotopic Biventricularly Loaded Cardiac Transplant in vivo Model. Eur Surg Res 2016; 57:171-185. [PMID: 27434273 DOI: 10.1159/000446515] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 05/01/2016] [Indexed: 11/19/2022]
Abstract
BACKGROUND Heterotopic heart transplantation (HHT) in rodent animal models represents an important technique enabling studies on organ transplantation immunology and pharmaceutical development. Recent investigations used nonworking HHT designs, with the left ventricle (LV) bypassed in the anastomosis system. In spite of their principal success, the lack of orthogonal ventricular filling leads to myocardial atrophy. However, when focusing on the cellular and molecular mechanisms involved in the in vivo remodeling of the myocardium or cell-based cardiovascular implants, a nonworking model is suboptimal as it lacks the native-analogous hemodynamic and metabolic situation. Here we present the hemodynamic and electrical assessment of a biventricularly loaded murine HHT method without the need for a combined heart-lung transplantation approach. METHODS Heterotopic transplantations (n = 13) were performed on C57BL/6J-(H-2b) inbred mice (n = 13 donors, n = 13 recipients) by creating end-to-side anastomoses between the donors' cranial vena cava (CrVC) and the recipients' abdominal caudal vena cava (CVC), between the donors' ascending aorta and the recipients' abdominal aorta (aAo), and between the grafts' pulmonary trunk and the left atrium. After transplantation, a hemodynamic assessment using echocardiography (including 2D speckle tracking analysis) and electrocardiography was performed. RESULTS The loaded HHT procedure in the mice was performed with an overall success rate of 61%. In 3 of the remaining 5 cases, only atrial function was restored. The median duration of the entire surgical procedure for the recipient animal was 190 (IQR 180-250) min. The mean heart rate in the loaded HHT group was 355 ± 6 bpm in comparison to the control group with an in situ heart rate of 418 ± 61 bpm. A native-like closing and opening pattern of the aortic and mitral valves (visible on both 2D and M-mode images) was observed, confirming a native-analogous loading of the LV. Pulsed-wave Doppler provided visualization of the flow across the region of anastomoses between the pulmonary trunk and the left atrium, reaching a mean maximum velocity of 382 ± 12 mm/s. Exemplary 2D speckle tracking analysis of the LV free wall and interventricular septum revealed some differences in vector directions in one animal when compared to the orthotopic native heart, indicating an asynchronous movement of the LV. CONCLUSIONS These results demonstrate the technical (micro)surgical feasibility of a fully loaded HHT procedure in the murine model without using a combined heart-lung transplantation approach. The acute hemodynamic performance of the HHT grafts approximated the native orthotopic situation. This model may open up new options for the investigation of cellular and molecular questions in the murine cardiovascular in vivo system in the near future.
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Affiliation(s)
- Agnieszka A Książek
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
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Kearns MJ, Wang Y, Boyd JH. Rat Heterotopic Abdominal Heart/Single-lung Transplantation in a Volume-loaded Configuration. J Vis Exp 2015:e52418. [PMID: 26068372 DOI: 10.3791/52418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Herein, we describe a novel technique for heterotopic abdominal heart-lung transplantation (HAHLT) in rats. The configuration of the transplant graft involves anastomosis of donor inferior vena cava (IVC) to recipient IVC, and donor ascending aorta (Ao) to recipient abdominal Ao. The right upper and middle lung lobes are preserved and function as conduits for blood flow from right heart to left heart. There are several advantages to using this technique, and it lends itself to a broad range of applications. Because the graft is transplanted in a configuration that allows for dyamic volume-loading, cardiac function may be directly assessed in vivo. The use of pressure-volume conductance catheters permits characterization of load-dependent and load-independent hemodynamic parameters. The graft may be converted to a loaded configuration by applying a clamp to the recipient's infra-hepatic IVC. We describe modified surgical techniques for both donor and recipient operations, and an ideal myocardial protection strategy. Depending on the experimental aim, this model may be adapted for use in both acute and chronic studies of graft function, immunologic status, and variable ventricular loading conditions. The conducting airways to the transplanted lung are preserved, and allow for acute lung re-ventilation. This facilitates analysis of the effects of the mixed venous and arterial blood providing coronary perfusion to the graft. A limitation of this model is its technical complexity. There is a significant learning curve for new operators, who should ideally be mentored in the technique. A surgical training background is advantageous for those wishing to apply this model. Despite its complexity, we aim to present the model in a clear and easily applicable format. Because of the physiologic similarity of this model to orthotopic transplantation, and its broad range of study applications, the effort invested in learning the technique is likely to be worthwhile.
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Affiliation(s)
- Mark J Kearns
- Cardiovascular Surgery, UBC James Hogg Research Center, St. Paul's Hospital;
| | - Yingjin Wang
- UBC James Hogg Research Center, St. Paul's Hospital
| | - John H Boyd
- Respiratory and Critical Care Medicine, UBC James Hogg Research Center, St. Paul's Hospital
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Lu W, Zheng J, Pan XD, Li B, Zhang JW, Wang LF, Sun LZ. A new simplified volume-loaded heterotopic rabbit heart transplant model with improved techniques and a standard operating procedure. J Thorac Dis 2015; 7:653-61. [PMID: 25973231 DOI: 10.3978/j.issn.2072-1439.2015.03.05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 02/28/2015] [Indexed: 11/14/2022]
Abstract
BACKGROUND The classic non-working (NW) heterotopic heart transplant (HTX) model in rodents had been widely used for researches related to immunology, graft rejection, evaluation of immunosuppressive therapies and organ preservation. But unloaded models are considered not suitable for some researches. Accordingly, We have constructed a volume-loaded (VL) model by a new and simple technique. METHODS Thirty male New Zealand White rabbits were randomly divided into two groups, group NW with 14 rabbits and group VL with 16 rabbits, which served as donors and recipients. We created a large and nonrestrictive shunt to provide left heart a sufficient preload. The donor superior vena cave and ascending aorta (AO) were anastomosed to the recipient abdominal aorta (AAO) and inferior vena cava (IVC), respectively. RESULTS No animals suffered from paralysis, pneumonia and lethal bleeding. Recipients' mortality and morbidity were 6.7% (1/15) and 13.3% (2/15), respectively. The cold ischemia time in group VL is slight longer than that in group NW. The maximal aortic velocity (MAV) of donor heart was approximately equivalent to half that of native heart in group VL. Moreover, the similar result was achieved in the parameter of late diastolic mitral inflow velocity between donor heart and native heart in group VL. The echocardiography (ECHO) showed a bidirectional flow in donor SVC of VL model, inflow during diastole and outflow during systole. PET-CT imaging showed the standard uptake value (SUV) of allograft was equal to that of native heart in both groups on the postoperative day 3. CONCLUSIONS We have developed a new VL model in rabbits, which imitates a native heart hemodynamically while only requiring a minor additional procedure. Surgical technique is simple compared with currently used HTX models. We also developed a standard operating procedure that significantly improved graft and recipient survival rate. This study may be useful for investigations in transplantation in which a working model is required.
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Affiliation(s)
- Wei Lu
- 1 Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China ; 2 Department of Pediatric Heart center, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Jun Zheng
- 1 Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China ; 2 Department of Pediatric Heart center, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Xu-Dong Pan
- 1 Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China ; 2 Department of Pediatric Heart center, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Bing Li
- 1 Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China ; 2 Department of Pediatric Heart center, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Jin-Wei Zhang
- 1 Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China ; 2 Department of Pediatric Heart center, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Long-Fei Wang
- 1 Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China ; 2 Department of Pediatric Heart center, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Li-Zhong Sun
- 1 Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing 100029, China ; 2 Department of Pediatric Heart center, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
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