Atrioventricular block secondary to transient causes and long-term recurrence after an index event.

BACKGROUND: Atrioventricular block (AVB) secondary to transient causes can recover with its correction. However, studies assessing predictors of recovery and long-term recurrence are lacking. METHODS: Patients with advanced or complete AVB who had a reversible cause admitted in a single expert center were retrospectively studied. Patients with AVB secondary to acute coronary syndromes were excluded from analysis. RESULTS: In a population of 162 patients, the main factors associated with recovery of rhythm without a permanent pacemaker (PPM) implantation were the presence of chronic kidney disease (CKD) on dialysis (OR 7.6; CI 95% 1.2-47.5 (p = .03)); greater serum potassium levels (OR 2.3; CI 95% 1.28-4.0 (p < .01)), higher dosage of bradycardic drugs (OR 2.2; CI 95% 1.13-4.4 (p = .02)), the association between different bradycardic drugs (OR 9.0; CI 95% 2.02-40.3 (p < .01)) and between drug therapy and hyperkaliemia (OR 5.2; CI 95% 1.8-15.1 (p < .01)). There was an overall high burden of conductions abnormalities which did not correlate with recovery of rhythm (OR 0.5; CI 95% 0.19-1.5 (p = .23)). In 29 patients (17.9%) there was a correction of the AVB. During a maximum follow-up of 130 months, 24 patients (82.8%) had a recurrence which warranted a PPM. In the overall cohort only five patients (3%) had sustained recovery of rhythm. CONCLUSIONS: Recovery of AVB was mainly observed with higher doses of drug therapy, higher serum potassium levels or a combination of factors and regardless of baseline conduction abnormalities. The high rate of recurrence during follow-up warrants a close follow-up or PPM implantation at index admission.

Clinical outcome of a single procedure cryoballoon ablation for the treatment of atrial fibrillation: A real-world multicenter experience in Portugal.

BACKGROUND: Cryoballoon ablation (CBA) for pulmonary vein isolation (PVI) has been growing as an alternative technique, not only in patients with paroxysmal atrial fibrillation (PAF) but also in persistent atrial fibrillation (AF). Cryoballoon ablation has demonstrated encouraging acute and mid-term results. However, data on long-term follow-up of CB-based PVI are scarce. OBJECTIVE: We sought to examine efficacy, safety, and long-term outcomes of CBA in PAF and persistent AF in four Portuguese centers. METHODS: All patients that were treated with the cryoballoon catheter according to routine practices with a second-generation 28-mm CB in four centers were included. This was a retrospective, non-randomized analysis. Patients were followed-up for >12 months and freedom from atrial arrhythmias (AA) was evaluated at the end of follow-up. RESULTS: Four hundred and six patients (57.7±12.4 years, 66% men) participated. AF was paroxysmal in 326 patients (80.2%) and persistent in 80 (19.7%). The mean procedure time duration was 107.7±50.9 min, and the fluoroscopy time was 19.5±9.7 min. Procedural/periprocedural complications occurred in 30 cases (7.3%), being transient phrenic nerve palsy the most frequent incident (2 out of 3 complications). Anatomic variations of the PV were present in 16.1% of cases. At a mean follow-up of 22.0±15.0 months, 310 patients (76.3%) remained in stable sinus rhythm, with at least one AF episode recurrence documented in 98 cases (24.1%). The recurrence rate was 20.5% in the PAF group and 37.8% in the persistent AF group. CONCLUSION: In this multicenter experience, a single CBA procedure resulted in 75.9% freedom from AF at a 22-month follow-up. This technique was demonstrated to be a safe and effective option in experienced centers for the treatment of PAF and PersAF.

Sudden Cardiac Death: The Most Feared but Potentially Preventable Presentation of Wolff-Parkinson-White Syndrome.

Background. Wolff-Parkinson-White syndrome is an uncommon cardiac disorder characterized by the presence of one or more accessory pathways that predispose patients to frequent episodes of arrhythmias. The prognosis is usually good, but there is a lifetime risk of malignant arrhythmias and sudden cardiac death. Case Summary. A 25-year-old male presented a witnessed out-of-hospital cardiac arrest with ventricular fibrillation rhythm. Due to rapid initiation of prehospital advanced life support, return of spontaneous circulation was observed. During the transport to the hospital, an irregular wide complex tachycardia suggestive of preexcited atrial fibrillation with haemodynamic instability was also observed and a synchronized shock was applied. Baseline 12-lead electrocardiogram was compatible with sinus rhythm and ventricular preexcitation pattern. After clinical stabilization, an electrophysiological study was performed confirming the presence of a left anterolateral accessory pathway with a short antegrade effective refractory period. Successful radiofrequency catheter ablation was achieved. Discussion. The reported clinical case recalls fundamental features of the Wolff-Parkinson-White syndrome and outlines the increasing evidence and importance of the invasive risk stratification and even catheter ablation in asymptomatic patients who suffer from this uncommon disease that may have a dramatic and fatal initial clinical manifestation.

Upper Bounds on the Multiplicative Complexity of Symmetric Boolean Functions.

A special metric of interest about Boolean functions is multiplicative complexity (MC): the minimum number of AND gates sufficient to implement a function with a Boolean circuit over the basis {XOR, AND, NOT}. In this paper we study the MC of symmetric Boolean functions, whose output is invariant upon reordering of the input variables. Based on the Hamming weight method from Muller and Preparata (1975), we introduce new techniques that yield circuits with fewer AND gates than upper bounded by Boyar et al. in 2000 and by Boyar and Peralta in 2008. We generate circuits for all such functions with up to 25 variables. As a special focus, we report concrete upper bounds for the MC of elementary symmetric functions ∑ k n and counting functions ∑ k n with up to n = 25 input variables. In particular, this allows us to answer two questions posed in 2008: both the elementary symmetric ∑ 4 8 and the counting ∑ 4 8 functions have MC 6. Furthermore, we show upper bounds for the maximum MC in the class of n-variable symmetric Boolean functions, for each n up to 132.

Psst, Can You Keep a Secret?

The security of encrypted data depends not only on the theoretical properties of cryptographic primitives but also on the robustness of their implementations in software and hardware. Threshold cryptography introduces a computational paradigm that enables higher assurance for such implementations.

Cardiac resynchronization therapy: Femoral approach.

We describe the case of a 62-year-old female patient with bilateral subclavian vein occlusion, in whom a cardiac resynchronization system was implanted via a femoral vein.

Robot-assisted ureteral reconstruction using a tubularized peritoneal flap: a novel technique in a chronic porcine model.

OBJECTIVE: To evaluate the feasibility and functional outcomes in porcine models of a novel robotic surgical technique for the treatment of complex ureteral injuries and strictures. MATERIALS AND METHODS: Six pigs underwent robotic ureteral reconstruction using a long tabularized peritoneal flap and followed for 6-9 weeks after the surgery. Ureteral flap vascularity, intra-renal pressure, patency of the conduct, endoscopic aspect of the flap, renal function and histopathology were evaluated. RESULTS: All animals successfully underwent ureteral reconstruction using a tubularized peritoneal flap. Median operative time was 223 min (162-360). Flap tubularization suture took 31 min (19-47), and proximal anastomosis took 20 min (15-38). Bladder mobilization with psoas hitch and distal anastomosis took 9 min (7-12) and 23 min (13-46), respectively. On follow-up, significant shrinkage of the ureteral flap in both length and width was observed. Antegrade pyelograms confirmed dilation and tortuosity of the proximal ureter, dilation of the renal pelvis, and major and minor calyxes without any definitive strictures. Microscopically, focal urothelial lining was seen in the neoureter. Creatinine level was significantly higher at the end of the follow-up period (p = 0.003). CONCLUSIONS: Robot-assisted ureteral reconstruction using a tubularized peritoneum flap is technically feasible and reproducible. The flap sustained abundant vascular supply after different intervals of follow-up and the peritoneal mesenchymal cells differentiated into urothelium and myofibroblasts. Further studies are needed to address the issue of functional obstruction to improve long-term renal function outcomes.

Impact of novel techniques on minimally invasive adrenal surgery: trends and outcomes from a contemporary international large series in urology.

OBJECTIVE: To evaluate contemporary international trends in the implementation of minimally invasive adrenalectomy and to assess contemporary outcomes of different minimally invasive techniques performed at urologic centers worldwide. METHODS: A retrospective multinational multicenter study of patients who underwent minimally invasive adrenalectomy from 2008 to 2013 at 14 urology institutions worldwide was included in the analysis. Cases were categorized based on the minimally invasive adrenalectomy technique: conventional laparoscopy (CL), robot-assisted laparoscopy (RAL), laparoendoscopic single-site surgery (LESS), and mini-laparoscopy (ML). The rates of the four treatment modalities were determined according to the year of surgery, and a regression analysis was performed for trends in all surgical modalities. RESULTS: Overall, a total of 737 adrenalectomies were performed across participating institutions and included in this analysis: 337 CL (46 % of cases), 57 ML (8 %), 263 LESS (36 %), and 80 RA (11 %). Overall, 204 (28 %) operations were performed with a retroperitoneal approach. The overall number of adrenalectomies increased from 2008 to 2013 (p = 0.05). A transperitoneal approach was preferred in all but the ML group (p < 0.001). European centers mostly adopted CL and ML techniques, whereas those from Asia and South America reported the highest rate in LESS procedures, and RAL was adopted to larger extent in the USA. LESS had the fastest increase in utilization at 6 %/year. The rate of RAL procedures increased at slower rates (2.2 %/year), similar to ML (1.7 %/year). Limitations of this study are the retrospective design and the lack of a cost analysis. CONCLUSIONS: Several minimally invasive surgical techniques for the management of adrenal masses are successfully implemented in urology institutions worldwide. CL and LESS seem to represent the most commonly adopted techniques, whereas ML and RAL are growing at a slower rate. All the MIS techniques can be safely and effectively performed for a variety of adrenal disease.

The transrectal single port laparoscopic radical prostatectomy in a cadaver model.

OBJECTIVE: To explore the feasibility of laparoscopic trans-rectal Natural Orifice Transluminal Endoscopic Surgery (NOTES) radical prostatectomy in a cadaveric model and to define anatomical landmarks of this surgical route. MATERIALS AND METHODS: After the ethical clearance, the study was conducted in Turkish Council of Forensic Medicine. With the cadaver in an exaggerated lithotomy position, a full thickness incision was made on the anterior wall of the rectum. The anteriorly visible Denonvilliers' fascia was incised sharply, exposing the posterior surface of the prostate. A single-port device (GelPOINT(®)Path) was inserted transanally passing the incision on the anterior wall of the rectum, into the bluntly created space between rectum and prostate. Three, 10 mm ports were placed through the GelPOINT(®)Path, at 3, 6, and 9 o'clock positions. A 5 mm, 0° degree lens was introduced at 6 o'clock position; followed by laparoscopic scissors and laparoscopic grasper. Prostatic and periprostatic anatomy was defined as encountered during each step of the procedure. RESULTS: Exposure of the posterior surface of the prostate and seminal vesicles was easily achieved. No additional openings of the rectal wall were made. Surgical specimen was extracted keeping its integrity. CONCLUSION: Transrectal radical prostatectomy is technically feasible in the cadaver model, being facilitated by previous experience with perineal surgery. Anatomical observations during the present experimental study suggest that the transrectal NOTES route provides good exposure of the operative field and easy access to the posterior surface of prostate, Future experimental endeavors should focus on reproducibility of this approach and feasibility of lymph node dissection using trans-rectal route.

Laparoendoscopic single site surgery versus conventional laparoscopy for transperitoneal pyeloplasty: A systematic review and meta-analysis.

We aimed to review studies comparing the outcomes of the laparoendoscopic single site (LESS) pyeloplasty with those of conventional laparoscopic pyeloplasty (CLP). A systematic review of the literature was performed according to the PRISMA (preferred reporting items for systematic reviews and meta-analysis) criteria. The methodological quality of the studies was rated according validated scales. The level of evidence (LE) was reported as described by the Oxford criteria. Preoperative demographic parameters and perioperative outcomes between the two surgical techniques were assessed. A meta-analysis of the included studies was performed. A total of 5 studies were elected for the analysis, including 164 cases, 70 (42.6%) of them being LESS and 94 (57.4%) being CLP. Four studies were observational retrospective comparative studies (LE: 3a-4); one was a prospective randomized controlled trial (LE: 2b). There was no significant difference in age, body mass index, gender, side and presence of the crossing vessel, between the groups. There was no significant difference regarding the operative time (weight mean difference [WMD]: -7.02; 95% confidence interval [CI]: -71.82-57.79; P = 0.83) and length of hospital stay (WMD: 0.04; 95% CI: -0.11-0.20; P = 0.58), whereas the estimated blood loss was statistically lower for LESS (WMD: -16.83; 95% CI: -31.79--1.87; P = 0.03). The postoperative use of analgesic favored the LESS group but without reaching statistical significance (WMD: -7.52; 95% CI: -17.56-2.53; P = 0.14). In conclusion, LESS pyeloplasty offers comparable surgical and functional outcomes to CLP while providing the potential advantages of less blood loss and lower analgesic requirement. Thus, despite being more technically challenging, LESS pyeloplasty can be regarded as a minimally invasive approach for patients seeking fewer incisional scars.

Use of biological Glue (Bioglue®) in laparoscopic partial nephrectomy: a study in pigs.

INTRODUCTION: Partial nephrectomy is the standard of care for localized renal tumors. However, bleeding and warm ischemia time are still controversial when laparoscopic surgeries are carried out. Herein, we aim to compare the outcomes from laparoscopic partial nephrectomy with and without the use of biological glue with purified bovine albumin and glutaraldehyde (BioGlue ®). MATERIALS AND METHODS: Twenty-four kidneys of 12 pigs were used in this study. A pre-determined lower pole segment was resected (3 cm x 1 cm) and one of two different hemostatic techniques was performed. In one kidney, hemostatic ″ U suture ″ (poliglecaprone 3.0) was performed and in the contra-lateral kidney, only the biological glue was applied. Data recorded was comprised of warm ischemia time (seconds) and estimated blood loss (mL) for each procedure. In cases of bleeding after glue administration, a complementary suture was done. RESULTS: Mean warm ischemia time was 492.9 ± 113.1 (351-665) seconds and 746 ± 185.3 (409-1125) seconds for biological glue and suture groups, respectively. There was a positive significant difference in terms of warm ischemia favoring the biological glue group over the suture group (p<0.001). Mean blood loss was 39.4 (0-115) mL for the biological glue group and 39.1 (5-120) mL for the suture group (p=0.62). CONCLUSION: Biological glue is an important tool for laparoscopic partial nephrectomies. It is effective for hemostatic control in selected cases, and it can be used in combination with the traditional suture techniques.

Use of biological Glue (Bioglue®) in laparoscopic partial nephrectomy: a study in pigs

Introduction Partial nephrectomy is the standard of care for localized renal tumors. However, bleeding and warm ischemia time are still controversial when laparoscopic surgeries are carried out. Herein, we aim to compare the outcomes from laparoscopic partial nephrectomy with and without the use of biological glue with purified bovine albumin and glutaraldehyde (BioGlue®). Materials and Methods Twenty-four kidneys of 12 pigs were used in this study. A pre-determined lower pole segment was resected (3 cm x 1 cm) and one of two different hemostatic techniques was performed. In one kidney, hemostatic “U suture” (poliglecaprone 3.0) was performed and in the contra-lateral kidney, only the biological glue was applied. Data recorded was comprised of warm ischemia time (seconds) and estimated blood loss (mL) for each procedure. In cases of bleeding after glue administration, a complementary suture was done. Results Mean warm ischemia time was 492.9±113.1 (351-665) seconds and 746±185.3 (409-1125) seconds for biological glue and suture groups, respectively. There was a positive significant difference in terms of warm ischemia favoring the biological glue group over the suture group (p<0.001). Mean blood loss was 39.4 (0-115) mL for the biological glue group and 39.1 (5-120) mL for the suture group (p=0.62). Conclusion Biological glue is an important tool for laparoscopic partial nephrectomies. It is effective for hemostatic control in selected cases, and it can be used in combination with the traditional suture techniques. .

Possible Detrimental Effects of Clamping Main Versus Segmental Renal Arteries for the Achievement of Renal Global Ischemia During Robot-Assisted Partial Nephrectomy.

PURPOSE: To determine the impacts of clamping the main renal artery vs individually clamping presegmental or segmental arteries at the time of global renal ischemia on the surgical and functional outcomes of robot-assisted partial nephrectomy (RAPN). PATIENTS AND METHODS: Patients who underwent RAPN at our center from 2009 to September 2013 were assessed for details of intraoperative renal arterial anatomy. Cases were divided into two groups according to the type of global renal ischemia: Group 1 consisted of cases where one main renal artery (or hilum) was clamped; group 2 included cases where multiple arteries or multiple branches of arteries were individually clamped. Patient demographics, tumor characteristics, perioperative data, functional outcomes (as well as pathology findings) were assessed for both groups. Univariable and multivariable analyses were performed for identifying factors predicting early (at day 3) estimated glomerular filtration rate (eGFR) preservation postoperatively. RESULTS: Group 1 and group 2 included 468 and 111 patients, respectively. Estimated blood loss and warm ischemia time (WIT) were comparable between the two groups. A higher proportion of combined arterial and venous clamping was observed in group 1 (76.2% vs 52.3%; P=0.0001). On postoperative day 3, eGFR preservation was not significantly different between the two groups (P=0.87). On multivariable analysis, WIT and preoperative eGFR remained the only significant predictors of early eGFR preservation. The number of arterial vessels clamped during the procedure or simultaneous arterial/vein clamping were not predictors of early eGFR preservation. CONCLUSIONS: Perioperative outcomes of RAPN are not influenced by clamping the main renal artery compared with clamping multiple branches of the renal artery for achievement of global renal ischemia. WIT and baseline eGFR were confirmed to be significant predictors of postoperative renal function preservation after RAPN.

Robot-assisted laparoscopic partial nephrectomy in patients with previous abdominal surgery: single center experience.

BACKGROUND: The aim of this study is to report our single center experience with robotic partial nephrectomy (RPN) in patients with history of previous abdominal surgery (PAS). METHODS: Medical records of patients who underwent RPN for a single renal mass in our center from 2006 to 2013 were reviewed. Patients were divided in two groups: those who had history of PAS and those without history of PAS. Within the PAS group, four sub-groups were considered: (a) remote site of PAS in relation to RPN; (b) PAS in the proximity of RPN site; (c) previous umbilical hernia/abdominal hernia mesh repair; (d) major PAS. RESULTS: In total 627 patients were analyzed, and of these 321 patients had history of PAS (51.2%). On univariable and multivariable analyses, only Charlson Comorbidity Index, estimated blood loss, and tumor size were the significant predictors of complications. CONCLUSIONS: RPN can be safely performed in patients with history of PAS with surgical outcomes comparable with those obtained in patients without history of PAS.