RESUMO
Current treatments of aortic aneurysm include surgical or endovascular, respectively, anatomical or functional, substitution of the aneurysm tract; however, with these methods, perfusion of at least some collateral branches cannot be fully restored, leading to the risk of paraplegia. We present a novel endovascular "net" prosthesis to strengthen the aortic wall while preserving perfusion of collateral branches. This consists of a polyester mesh "net"-layered conduit in a variable cylindrical shape, which is personalized based on patient computed tomography scan images, and is defined by circular crossing spirals of a thin nitinol wire. The prosthetic conduit, shrunk by compressing the nitinol spirals, can be inserted into the vascular lumen and expanded in situ. Then, the insertion control device can be fully removed. Thus, the, "net" prosthesis, positioned inside the aorta in stable contact with the intimal wall for 2 to 5 months, is colonized by neointima and spontaneously moved deeper into the aortic wall in contact with the media, thus being ideally able to stabilize aortic diameter without interference with collateral branch blood perfusion. This new, (ideally) paraplegia-free procedure is aimed at curing the aortic wall structural defect, thus arresting the aneurysm from further progression. This contrasts with current treatments, indicated by aneurysm dimensions for their implied complication risk, which are actually for prophylaxis of impending rupture or dissection rather than fortification of the natural aorta. Moreover, this new approach can be used alongside open surgical procedures (personalized external aortic root support) as well as a frozen "net" elephant trunk technique, for full aortic stabilization.
RESUMO
Paraplegia in aortic surgery is due to its impact on spinal cord perfusion whose hemodynamic patterns (SCPHP) are not clearly defined. Detailed morphological analysis of vascular network and collateral network modifications within Monro-Kellie postulate due to the fixed theca confines was performed to identify SCPHP. SCPHP may begin with intraspinal "backflow" (I-BF), that is, hemorrhage from anterior and posterior spinal arteries, backward via the connected anterior and posterior radicular medullary arteries, through the increasing diameter and decreasing resistance of segmental arteries (SAs), off their aortic orifices outside vascular network at 0 operative field pressure. The I-BF blood bypasses both intra- and extraspinal capillary networks and causes depressurization (0 diastolic pressure) and full ischemia of dependent spinal cord. When the occlusion of those SAs orifices arrests I-BF, the hemodynamic pattern of intraspinal "steal" (I-S) may take place. The formerly I-BF blood, in fact, is now variably shared between the fraction maintained in its physiological intraspinal network and that keeping flowing as I-S through the extraspinal capillary network. I-S is, however, counteracted by the extraspinal "steal" from the connected mammary/paraspinous-independent extraspinal feeders, all physically competing for the same room left by the missed physiological SA direct aortic blood inflow. Steal phenomenon evolves within the 120-hour time frame of CNm, whose intraspinal anatomical changes may offer the physical basis within the Monro-Kelly postulate, respectively of the intraoperative and postoperative paraplegia. The current procedures could not prevent the unphysiological SCPHP but awareness of details of their various features may offer the basis for improvements tailored, to the adopted intra- and postoperative procedures.
Assuntos
Aneurisma Aórtico/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Desenho Assistido por Computador , Síndrome de Marfan/cirurgia , Aneurisma Aórtico/etiologia , Aneurisma Aórtico/patologia , Implante de Prótese Vascular/efeitos adversos , Humanos , Síndrome de Marfan/complicações , Síndrome de Marfan/patologia , Desenho de Prótese , Telas Cirúrgicas , Fatores de Tempo , Resultado do TratamentoAssuntos
Cordas Tendinosas/cirurgia , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral/cirurgia , Ponte Cardiopulmonar , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Índice de Gravidade de Doença , Estresse Mecânico , Técnicas de Sutura , Fatores de Tempo , Resultado do TratamentoRESUMO
In past years, we developed expandable devices (type I and II) for sutureless aortic anastomosis. We have now further modified the device (type III) incorporating a second expandable ring, external to the main one, which can be operated contrariwise in such a way that the aortic wall (i.e. the dissection layers) is compressed between the two expandable rings, providing full control on both the layers compression pressure and the anastomosis final diameter. The device was evaluated in ex vivo experimental models of swine aortic arch fresh samples; air-tight sealing at increasing endovascular pressures was also evaluated and compared with sealing achieved by standard suturing. Ex vivo data suggest that the present version of the device can be used easily and quickly also in elliptical, asymmetric 'oblique' anastomosis as when concavity arch is involved. Perfect air-tight sealing of the anastomosis was verified at endovascular pressures up to 150 mmHg, while standard suture cannot withstand even minimal endovascular air pressure. Compared to the previous versions, the present device is less bulky and softer, can be used also for concavity arch resection and provides full and standardizable control on dissection layers stable and sealed approximation.
Assuntos
Aorta/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Anastomose Cirúrgica , Animais , Técnicas In Vitro , Teste de Materiais , Modelos Animais , Pressão , Desenho de Prótese , Técnicas de Sutura , SuínosAssuntos
Implante de Prótese Vascular/efeitos adversos , Hipotensão/etiologia , Síndrome da Veia Cava Superior/cirurgia , Neoplasias Vasculares/cirurgia , Idoso , Constrição , Feminino , Humanos , Hipotensão/epidemiologia , Hipotensão/terapia , Incidência , Complicações Intraoperatórias , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Síndrome da Veia Cava Superior/etiologia , Neoplasias Vasculares/complicações , Veia Cava Superior/patologia , Veia Cava Superior/cirurgiaRESUMO
We report a case of primary synovial sarcoma of the lung. The patient was a 32-year-old male who presented with a mass in the right hemithorax invading the peritoneal cavity. The neoplasm was resected through a thoracic-abdominal approach. The patient is doing well 21 months after surgery. Within the last decade thoracic localizations of synovial sarcoma are an emerging histopathological entity thanks to the molecular analysis of the SYT-SSX fusion gene transcript.
Assuntos
Neoplasias Pulmonares/cirurgia , Sarcoma Sinovial/cirurgia , Adulto , Humanos , Laparotomia/métodos , Neoplasias Pulmonares/patologia , Masculino , Nervo Frênico/cirurgia , Sarcoma Sinovial/patologia , Toracotomia/métodosRESUMO
To reduce the time needed for clamping or circulatory arrest (or both) during substitution of a prosthesis for the thoracic aorta, we developed an expandable device that can be used with any commercially available prosthetic graft to enable sutureless aortic anastomosis. Improvements upon a previous version of the device include the use of nickel-titanium alloy (Nitinol) instead of stainless steel. This, together with an improved wire-looping design, now enables continuous control of diameter, even when the device is in contact with blood. A further improvement consists of 4 metallic hooks on the outer surface, which enable firm fixation to the aortic stump. In March 2001, a 47-year-old man was admitted to our institution for evaluation of left upper-lobe bronchogenic adenocarcinoma that had infiltrated the distal aortic arch and upper descending aorta. Re-staging of the neoplasm ruled out distant metastasis. We resected the infiltrated aortic wall en bloc with the upper lobe. The expandable device enabled the distal anastomosis of the aortic prosthesis to be performed easily, in less than 3 minutes. The main advantages of this device are an easier, quicker anastomosis and the absolute prevention of suture-line hemorrhage (no suture line). The expandable device overcomes the drawbacks of the intraluminal ringed prosthesis used in the past.