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1.
IntroductionAlthough free flaps have been used predominantly in past decades for the soft tissue reconstruction of head and neck malignancies, Pectoralis major myocutaneous flap (PMMF) is still a reliable workhorse for patients with co-existing co-morbidities or low economic status where free flaps are not feasible.Patients and methodsIt was a retrospective study done on 36 patients of head and neck malignancies over the period of 5 years in which PMMF was used as a method of reconstruction in our hospital. Patients were followed up for a period of one year and outcome of PMMF was evaluated.ResultsOut of 36 patients 31 were of oral cancer and 5 were of carcinoma hypopharynx. Incidence of total flap necrosis was nil and partial flap necrosis was 16.6%. Orocutaneous fistula was found in 16.6%, wound dehiscence was in 19.4% and infection was found in 13.5% of patients. Non-flap related complications were found in 13.8% of patients. 35 out of 36 patients (97.2%) eventually achieved satisfactory surgical outcome of PMMF reconstruction.ConclusionPMMF is a reliable method of reconstruction for head and neck malignancies especially in basic healthcare settings. With minimal expertise and groundwork, it is still a cost-effective workhorse flap for head and neck reconstruction.  相似文献   
2.

Introduction and objectives

Current therapeutic options for severe aortic stenosis (AS) include transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR). Our aim was to describe the prognosis of patients with severe AS after the decision to perform an intervention, to study the variables influencing their prognosis, and to describe the determinants of waiting time > 2 months.

Methods

Subanalysis of the IDEAS (Influence of the Severe Aortic Stenosis Diagnosis) registry in patients indicated for TAVI or SAVR.

Results

Of 726 patients with severe AS diagnosed in January 2014, the decision to perform an intervention was made in 300, who were included in the present study. The mean age was 74.0 ± 9.7 years. A total of 258 (86.0%) underwent an intervention: 59 TAVI and 199 SAVR. At the end of the year, 42 patients (14.0%) with an indication for an intervention did not receive it, either because they remained on the waiting list (34 patients) or died while waiting for the procedure (8 patients). Of the patients who died while on the waiting list, half did so in the first 100 days. The mean waiting time was 2.9 ± 1.6 for TAVI and 3.5 ± 0.2 months for SAVR (P = .03). The independent predictors of mortality were male sex (HR, 2.6; 95%CI, 1.1-6.0), moderate-severe mitral regurgitation (HR, 2.6; 95%CI, 1.5-4.5), reduced mobility (HR, 4.6; 95%CI, 1.7-12.6), and nonintervention (HR, 2.3; 95%CI, 1.02-5.03).

Conclusions

Patients with severe aortic stenosis awaiting therapeutic procedures have a high mortality risk. Some clinical indicators predict a worse prognosis and suggest the need for early intervention.  相似文献   
3.
Introduction and objectivesThis study aimed to determine the safety and efficacy of modifying the classic implantation technique for aortic transcatheter heart valve (THV) implantation to a cusp-overlap-projection (COP) technique to achieve a higher implantation depth and to reduce the burden of new permanent pacemaker implantation (PPMI) at 30 days. Aortic self-expanding THV carries an elevated risk for PPMI. A higher implantation depth minimizes the damage in the conduction system and may reduce PPMI rates.MethodsFrom March 2017, 226 patients were consecutively included: 113 patients were treated using the COP implantation technique compared with the previous 113 consecutive patients treated using the classic technique. In all patients, implantation depth was assessed by 3 methods (noncoronary cusp to the THV, mean of the noncoronary cusp and the left coronary cusp to the THV, and the deepest edge from the left coronary cusp and the noncoronary cusp to the THV).ResultsThe COP group had a lower implantation depth than the group treated with the classic technique (4.8 mm ± 2.2 vs 5.7 mm ± 3.1; P = .011; 5.8 mm ± 3.1 vs 6.5 mm ± 2.4; P = .095; 7.1 mm ± 2.8 vs 7.4 mm ± 3.2; P = .392). Forty patients (17.7%) required a new PPMI after the 30-day follow-up but this requirement was significantly lower in the COP group (12.4% vs 23%, P = .036). The COP implantation technique consistently protected against the main event (OR, 0.45; 95%CI, 0.21-0.97; P = .043), with similar procedural success rates and complications.ConclusionsThe COP implantation technique is a simple modification of the implantation protocol and provides a higher implantation depth of self-expanding-THV with lower conduction disturbances and PPMI rates.  相似文献   
4.
ObjectivesThis study sought to evaluate the impact of the ACURATE neo (NEO) (Boston Scientific, Marlborough, Massachusetts) versus SAPIEN 3 (S3) (Edwards Lifesciences, Irvine, California) on permanent pacemaker implantation (PPI) in patients with pre-existing right bundle branch block (RBBB) after transcatheter aortic valve replacement.BackgroundPre-existing RBBB is the strongest patient-related predictor for PPI after transcatheter aortic valve replacement. No comparison of newer-generation transcatheter heart valves with regard to PPI in these patients exists.MethodsThis multicenter registry includes 4,305 patients; 296 (6.9%) had pre-existent RBBB and no pacemaker at baseline and formed the study population. The primary endpoint was new PPI at 30 days. The association of NEO versus S3 with PPI was assessed using binary logistic regression analyses and inverse probability treatment weighting in a propensity-matched population.ResultsThe 30-day PPI rate was 39.2%. The S3 and NEO were used in 66.9% and 33.1%, respectively. The NEO was associated with lower rates of PPI compared with the S3 (29.6% vs. 43.9%; p = 0.025; odds ratio [OR]: 0.54; 95% confidence interval [CI]: 0.32 to 0.89; p = 0.018), after multivariable adjustment (OR: 0.48; 95% CI: 0.26 to 0.86; p = 0.014), and in the inverse probability treatment weighting analysis (OR: 0.37; 95% CI: 0.25 to 0.55; p < 0.001). There was no difference in device failure (8.2% vs. 6.6%; p = 0.792) or in-hospital course. In the propensity-matched population, PPI rate was also lower in the NEO versus S3 (23.1% vs. 44.6%; p = 0.016; OR: 0.37; 95% CI: 0.17 to 0.78; p = 0.010), with no difference in device failure (9.2% vs. 6.2%; p = 0.742).ConclusionsIn patients with RBBB, risk of PPI was significantly lower with the NEO compared with the S3, suggesting the possibility of a patient tailored transcatheter heart valve therapy.  相似文献   
5.
Predicting response to neo‐adjuvant chemotherapy (NAC) and survival in locally advanced breast cancer (LABC) is important. This study investigated the prognostic value of tumor heterogeneity evaluated with textural analysis through F‐18 fluorodeoxyglucose (FDG) positron emission tomography (PET) and diffusion‐weighted imaging (DWI). We enrolled 83 patients with LABC who had completed NAC and curative surgery. Tumor texture indices from pretreatment FDG PET and DWI were extracted from histogram analysis and 7 different parent matrices: co‐occurrence matrix, the voxel‐alignment matrix, neighborhood intensity difference matrix, intensity size‐zone matrix (ISZM), normalized gray‐level co‐occurrence matrix (NGLCM), neighboring gray‐level dependence matrix (NGLDM), and texture spectrum matrix. The predictive values of textural features were tested regarding both pathologic NAC response and progression‐free survival. Among 83 patients, 46 were pathologic responders, while 37 were nonresponders. The PET texture indices from 7 parent matrices, DWI texture indices from histogram, and 1 parent matrix (NGLCM) showed significant differences according to NAC response. On multivariable analysis, number nonuniformity of PET extracted from the NGLDM was an independent predictor of pathologic response (P = .009). During a median follow‐up period of 17.3 months, 14 patients experienced recurrence. High‐intensity zone emphasis (HIZE) and high‐intensity short‐zone emphasis (HISZE) from PET extracted from ISZM were significant textural predictors (P = .011 and P = .033). On Cox regression analysis, only HIZE was a significant predictor of recurrence (P = .027), while HISZE showed borderline significance (P = .107). Tumor texture indices are useful for NAC response prediction in LABC. Moreover, PET texture indices can help to predict disease recurrence.  相似文献   
6.
Teeth are richly supported by blood vessels and peripheral nerves. The aim of this study was to describe in detail the developmental time‐course and localization of blood vessels during early tooth formation and to compare that to innervation, as well as to address the putative role of vascular endothelial growth factor (VEGF), which is an essential regulator of vasculature development, in this process. The localization of blood vessels and neurites was compared using double immunofluorescence staining on sections at consecutive stages of the embryonic (E) and postnatal (PN) mandibular first molar tooth germ (E11‐PN7). Cellular mRNA expression domains of VEGF and its signaling receptor VEGFR2 were studied using sectional radioactive in situ hybridization. Expression of VEGF mRNA and the encoded protein were studied by RT‐PCR and western blot analysis, respectively, in the cap and early bell stage tooth germs, respectively. VEGFR2 was immunolocalized on tooth tissue sections. Smooth muscle cells were investigated by anti‐alpha smooth muscle actin (αSMA) antibodies. VEGF showed developmentally regulated epithelial and mesenchymal mRNA expression domains including the enamel knot signaling centers that correlated with the growth and navigation of the blood vessels expressing Vegfr2 and VEGFR2 to the dental papilla and enamel organ. Developing blood vessels were present in the jaw mesenchyme including the presumptive dental mesenchyme before the appearance of the epithelial dental placode and dental neurites. Similarly, formation of a blood vessel plexus around the bud stage tooth germ and ingrowth of vessels into dental papilla at E14 preceded ingrowth of neurites. Subsequently, pioneer blood vessels in the dental papilla started to receive smooth muscle coverage at the early embryonic bell stage. Establishment and patterning of the blood vessels and nerves during tooth formation are developmentally regulated, stepwise processes that likely involve differential patterning mechanisms. Development of tooth vascular supply is proposed to be regulated by local, tooth‐specific regulation by epithelial–mesenchymal tissue interactions and involving tooth target expressed VEGF signaling. Further investigations on tooth vascular development by local VEGF signaling, as well as how tooth innervation and development of blood vessels are integrated with advancing tooth organ formation by local signaling mechanisms, are warranted.  相似文献   
7.
8.
ObjectiveThe aim of this study is to describe in depth the precise anatomy of the vascular supply of the submandibular gland, trying to determine the existence of patterns of glandular vascularization. Knowledge of these patterns could facilitate surgical management of the gland and the submandibular gland flap.Material and methodsNeck dissections of formaldehyde preserved human cadavers were performed. Submandibular and transmandibular approaches were used during the dissections. All the vascular branches found were registered and classified into 2groups: main or accessory branches. The anatomical data analyzed was: The diameter and length of the main and accessory branches, as well as the most important measurements of the submandibular gland flap pedicle.Results33 glands were dissected to study the arterial supply of the submandibular gland (17 right, 16 left; 17 males, 16 females) and 29 were dissected to study the venous supply (15 left, 14 right; 15 males,14 females). A total of 123 arterial branches were found reaching the 33 submandibular glands (47 main and 76 accessories) and 116 venous branches were found draining the 29 submandibular glands (47 main branches and 69 accessory branches). A constant main venous branch that ran parallel to the Wharton duct and drained in the sublingual vein was found in all of cases (Concomitant Wharton Duct Vein or CWDV).ConclusionThe CWDV is a constant venous branch for the drainage of the gland and should be considered as venous pedicle during the dissection of submandibular gland flaps.  相似文献   
9.
BackgroundThe implications and potential challenges of coronary access after redo transcatheter aortic valve replacement (TAVR) are unknown.ObjectivesThe authors sought to evaluate the impact of different transcatheter heart valve (THV) designs, neoskirt height, implant technique, and cell misalignment on coronary access after redo TAVR.MethodsDifferent THV designs (Sapien 3 [Edwards Lifesciences LLC], Evolut Pro [Medtronic], ACURATE neo [Boston Scientific Corporation], and Portico [Abbott Structural Heart]) and sizes were implanted inside Sapien XT (Edwards Lifesciences LLC) and Evolut R (Medtronic) THVs, which were modeled as the “failed” THVs, at different implant depths. Valve combinations underwent micro–computed tomography to determine the neoskirt height and dimensions of the lowest accessible cell for potential coronary access. This was compared with dimensions of 6-F/7-F/8-F coronary guiding catheters.ResultsRedo TAVR combinations resulted in a wide range of neoskirt heights (15.4-31.6 mm) and a variable diameter of the lowest accessible cell (1.9-21.8 mm). An ACURATE neo implanted in a Sapien XT resulted in the largest accessible cells, whereas a Portico implanted in a Sapien XT resulted in the lowest neoskirt heights. The smallest accessible cell was observed in the Evolut Pro–in–Evolut R configuration with higher neoskirt heights. Redo TAVR in a tall frame valve with supra-annular leaflets caused a taller neoskirt height. In Evolut-in-Evolut combinations, misalignment of the cells of the 2 THVs reduced the cell area by 30% to 50% compared with an aligned configuration.ConclusionsThis study demonstrates that different redo TAVR combinations are not equivalent in terms of future coronary access. Redo TAVR using a tall frame valve in a failed tall frame valve and misaligned cells may lead to potentially challenging coronary access.  相似文献   
10.
目的:使用内皮祖细胞再内皮化胰腺脱细胞支架,并初步评价其在宿主体内生成血管的能力。方法:采用灌注法制备结构完整的全胰腺脱细胞支架;并提取大鼠骨髓单个核细胞,诱导分化为内皮祖细胞,进行原代培养;将培养完成的内皮种植于支架内,并行体内移植。结果:在移植后第10天,实验组中包含红细胞的血管管腔数为(43±6)cm2,而对照组为(8±3)cm2;在移植后第20天,实验组中包含红细胞的血管管腔数为(62±9)cm2,而对照组为(16±5)cm2,此结果具有统计学意义(P<0.05,n=6)。种植内皮祖细胞后,支架在体内能更快更多的生成新生血管,与对照组比较差异有统计学意义(P<0.05)。结论:再血管化的支架在体内移植后,与对照组相比,可以更快的与宿主循环系统形成吻合。  相似文献   
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