Experimental Devices Versus Hand-Sewn Anastomosis of the Aorta: A Systematic Review and Meta-Analysis.

BACKGROUND: To minimize complications associated with the construction of the hand-sewn aortic anastomosis, alternative experimental methods have been pursued. This study aimed to evaluate the efficacy of experimental anastomotic devices in relation to time and point of rupture of the anastomosis in comparison to the conventional technique. MATERIALS AND METHODS: An electronic search was performed using MEDLINE, Scopus, Science Direct, and Cochrane Library databases by two independent authors. Our exclusion criteria referred to studies reporting results solely from end-to-side anastomosis, results on vessels other than the aorta, studies that did not involve animal experiments, and non-English publications. The last search date was January 1, 2020. RESULTS: The meta-analysis included 22 studies with 34 anastomosis samples and a total of 316 animals. The pooled mean automated anastomosis time was 10.38 min, and the mean point of rupture was 32.7 N. In the subgroup analysis of automated anastomosis time by device category, the anastomotic stenting technique reported significantly lower anastomosis time but also showed significantly lower point of rupture. Comparing the efficacy of experimental devices and the hand-sewn technique, our pooled analysis showed that automated devices significantly decrease the time needed to perform the anastomosis (weighted mean difference -7.24 min). On the other hand, the automated anastomosis is also associated with decreased tensile strength (weighted mean difference -20.68 N). CONCLUSIONS: Although experimental devices seem to offer a faster anastomosis, they lack endurance when compared with the hand-sewn technique. Further research is needed for the development of an "ideal" anastomotic technique.

Α systematic review and meta-analysis of the efficacy of aortic anastomotic devices.

OBJECTIVE: One of the factors contributing to complications related to open repair of the aorta is the construction of a hand-sewn anastomosis. Aortic anastomotic devices (AADs), such as the intraluminal ringed graft (IRG), and the anastomotic stenting technique have been developed to perform a sutureless and less complicated anastomosis. This study performed a systematic review and meta-analysis of the literature reporting clinical use of AADs and aimed to assess, primarily, the effect of each device on 30-day overall and operation-related mortality and aortic cross-clamping time and, secondarily, the rate of successful two-sided application of the IRG device and the operation-related morbidity for each device. METHODS: An electronic search was performed using MEDLINE, Scopus, ScienceDirect, and Cochrane Library by two independent authors. Our exclusion criteria included studies incorporating fewer than three patients and studies reporting results solely from animals or in vitro testing, results solely from end-to-side anastomosis, and results solely from endarterectomy procedures. The last search date was February 1, 2018. RESULTS: A total of 41 studies were identified that reported outcomes for the use of three different device types: IRG, anastomotic stenting technique, and surgical staplers. The last two types were classified together as the non-IRG group. The meta-analysis included 27 studies with 50 cohorts incorporating 1260 patients. The median age of the incorporated patients was 61.4 years (range, 51-73 years), and 68.9% were male. The operations were performed for the treatment of acute aortic dissection in 82.3%. The pooled overall 30-day mortality rate varied by device type; IRG devices had a mean rate of all-cause mortality of 9.71%, whereas non-IRG devices were associated with a significantly (I2 = 15.78%; P for Cochrane Q test < .19) lower rate of death (1.47%). The pooled mean aortic cross-clamping time was 35.83 minutes. Metaregression showed that the performance of two-sided anastomosis with the IRG device significantly decreased the aortic cross-clamping time. However, a successful two-sided ringed anastomosis was performed in approximately half of the cases. CONCLUSIONS: Taking into account that the majority of operations were performed for the treatment of acute aortic dissection, AADs had a relatively low rate of 30-day mortality. Despite the observed heterogeneity in study protocols and the small sample size in the non-IRG group, the non-IRG group presented with the lowest 30-day mortality rate. Specific device-related complications between the different device types need further investigation.

3D Bioprinting Methods and Techniques: Applications on Artificial Blood Vessel Fabrication.

Three-dimensional (3D) printing has rapidly evolved, with major applications in the field of medicine. One of the greatest advances leading to 3D bioprinting was the development of biomaterials, cells and supporting components for the fabrication of functional living tissues. Several different methods and techniques of 3D bioprinting are briefly described in this review article, and applications of 3D printing for the fabrication of artificial blood vessels and grafts are presented. Advances in additive manufacturing techniques, medical imaging modalities, biomaterials and cellular engineering will lead to further developments in the fabrication of patient-specific vascular tissue constructs. Future multidisciplinary research and innovations are expected to further transform the fields of tissue engineering and regenerative medicine.

Precision Medicine in Aortic Anastomosis: A Numerical and Experimental Study of a Novel Double-Sided Needle.

BACKGROUND: Hand-sewn anastomosis is a crucial part of aortic reconstruction surgery and significantly affects its outcome. The present study presents a novel, bidirectional surgical needle aimed to improve aortic anastomosis in terms of speed and ease of use. Our objective was to assess the efficacy of the new design in comparison with the conventional needle. METHODS: A series of simulations were conducted with COMSOL software in order to perform a fatigue comparative analysis between the new and the conventional needle design. Ease of penetration into a piece of polydimethylsiloxane was evaluated. Lastly, the prototype was tested under in-vitro conditions in comparison with the conventional needle. RESULTS: Based on fatigue analysis, the new needle design improves durability, provided the two tips are equally used. The polytetrafluoroethylene coating improves penetration into the tissue by 7% to 17%, while electropolishing improves penetration up to 19%. When using the novel needle design, the average anastomotic task completion time was significantly reduced by 22% and the overall distance of hand movements was significantly reduced by 20%. CONCLUSIONS: The proposed design exhibited a shorter anastomotic time and seems promising in relation to ease of use and simplicity of the anastomotic technique it introduces.

Blood Pressure Deviation from the Golden Ratio φ and All-cause Mortality: A Pythagorean View of the Arterial Pulse.

INTRODUCTION: There is one mathematical element with strong historical and philosophical background that exhibits remarkable properties and applications; the golden ratio (phi). Mathematically, the golden ratio equals approximately 1.61803. A rather provocative geometrical analysis of the arterial pulse according to the golden ratio was recently described, and herein, we aim to set out the hypothesis that individuals with blood pressure (BP) values that follow the golden ratio may have different prognosis than those whose BPs deviate from the divine proportions. MATERIALS AND METHODS: We used published data from the National Health and Nutrition Examination Survey during 1999-2010. RESULTS: We found that the deviation of the BP values from the golden ratio is independently associated with all-cause mortality. CONCLUSIONS: This observation stimulates further research of the potential utility of the golden ratio of BP values on the diagnosis and prediction of BP-related abnormalities and risk.