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BackgroundCentral blood pressure (cBP) is a better indicator of cardiovascular morbidity and mortality than peripheral BP (pBP). However, direct cBP measurement requires invasive techniques and indirect cBP measurement is based on rigid and empirical transfer functions applied to pBP. Thus, development of a personalized and well-validated method for non-invasive derivation of cBP from pBP is necessary to facilitate the clinical routine. The purpose of the present study was to develop a novel blind source separation tool to separate a single recording of pBP into their pressure waveforms composing its dynamics, to identify the compounds that lead to pressure waveform distortion at the periphery, and to estimate the cBP. The approach is patient-specific and extracts the underlying blind pressure waveforms in pBP without additional brachial cuff calibration or any a priori assumption on the arterial model.MethodsThe intra-arterial femoral BPfe and intra-aortic pressure BPao were anonymized digital recordings from previous routine cardiac catheterizations of eight patients at the German Heart Centre Berlin. The underlying pressure waveforms in BPfe were extracted by the single-channel independent component analysis (SCICA). The accuracy of the SCICA model to estimate the whole cBP waveform was evaluated by the mean absolute error (MAE), the root mean square error (RMSE), the relative RMSE (RRMSE), and the intraclass correlation coefficient (ICC). The agreement between the intra-aortic and estimated parameters including systolic (SBP), diastolic (DBP), mean arterial pressure (MAP), and pulse pressure (PP) was evaluated by the regression and Bland–Altman analyses.ResultsThe SCICA tool estimated the cBP waveform non-invasively from the intra-arterial BPfe with an MAE of 0.159 ± 1.629, an RMSE of 5.153 ± 0.957 mmHg, an RRMSE of 5.424 ± 1.304%, and an ICC of 0.94, as well as two waveforms contributing to morphological distortion at the femoral artery. The regression analysis showed a strong linear trend between the estimated and intra-aortic SBP, DBP, MAP, and PP with high coefficient of determination R2 of 0.98, 0.99, 0.99, and 0.97 respectively. The Bland–Altman plots demonstrated good agreement between estimated and intra-aortic parameters with a mean error and a standard deviation of difference of −0.54 ± 2.42 mmHg [95% confidence interval (CI): −5.28 to 4.20] for SBP, −1.97 ± 1.62 mmHg (95% CI: −5.14 to 1.20) for DBP, −1.49 ± 1.40 mmHg (95% CI: −4.25 to 1.26) for MAP, and 1.43 ± 2.79 mmHg (95% CI: −4.03 to 6.90) for PP.ConclusionsThe SCICA approach is a powerful tool that identifies sources contributing to morphological distortion at peripheral arteries and estimates cBP.

IntroductionNeoadjuvant conventional chemoradiation (CRT) is the standard treatment for primary locally non-curatively resectable rectal cancer, as tumor downsizing may allow R0 resectability. Short-term neoadjuvant radiotherapy (5x5 Gy) followed by an interval before surgery (SRT- delay) is an alternative for multimorbid patients who cannot tolerate CRT. This study examined the extent of tumor downsizing achieved with the SRT-delay approach in a limited cohort that underwent complete re-staging before surgery.MethodsBetween March 2018 and July 2021, 26 patients with locally advanced primary adenocarcinoma (>uT3 or/and N+) of the rectum were treated with SRT-delay. 22 patients underwent initial staging and complete re-staging (CT, endoscopy, MRI). Tumor downsizing was assessed by staging and re-staging data and pathologic findings. Semiautomated measurement of tumor volume was performed using mint Lesion™ 1.8 software to evaluate tumor regression.ResultsThe mean tumor diameter determined on sagittal T2 MRI images decreased significantly from 54.1 (23–78) mm at initial staging to 37.9 (18–65) mm at re-staging before surgery (p

Introduction: The repair of subxiphoidal incisional hernia following median sternotomy is technically demanding due to the specific anatomic situation and the lateral distracting forces in this region. Published data are available from retrospective reports with limited number of patients only. The aim of this study was to evaluate the outcome of subxiphoidal hernia repair comparing laparoscopic and open surgical approach.Materials and Methods: This analysis of Herniamed registry data of patients with subxiphoidal incisional hernia following sternotomy for coronary bypass assesses the perioperative and 1 year follow-up outcome of laparoscopic and open repair. Demographic data and perioperative outcomes were stratified by surgical approach (laparoscopic vs. open) and compared as unadjusted analyses using Chi square and Students t-tests.Results: Of 208 patients identified for the analysis 69 patients (33.2%) underwent laparoscopic and 139 (66.8%) patients had open repair. Concerning demographic data (gender, age, BMI, ASA score), risk factors and hernia size there were no significant differences between laparoscopic and open repair group. For intraoperative, postoperative and general complications as well as complication related re-operations no significant differences were seen between the groups. No significant advantage could be stated for laparoscopic repair regarding duration of operation and hospital stay. The recurrence rate at 1 year follow-up was higher in the laparoscopic group (7.2 vs. 2.2%; p = 0.072). No significant differences were reported in the 1 year follow-up evaluation of pain at rest, pain on exertion and pain requiring treatment.Conclusion: The repair of subxiphoidal incisional hernia is safe in both open and laparoscopic technique. With regard to the lower recurrence rate preference can be given to open repair.