Estimating Surgical Urethral Length on Intraoperative Robot-Assisted Prostatectomy Images Using Artificial Intelligence Anatomy Recognition.

Objective: To construct a convolutional neural network (CNN) model that can recognize and delineate anatomic structures on intraoperative video frames of robot-assisted radical prostatectomy (RARP) and to use these annotations to predict the surgical urethral length (SUL). Background: Urethral dissection during RARP impacts patient urinary incontinence (UI) outcomes, and requires extensive training. Large differences exist between incontinence outcomes of different urologists and hospitals. Also, surgeon experience and education are critical toward optimal outcomes. Therefore, new approaches are warranted. SUL is associated with UI. Artificial intelligence (AI) surgical image segmentation using a CNN could automate SUL estimation and contribute toward future AI-assisted RARP and surgeon guidance. Methods: Eighty-eight intraoperative RARP videos between June 2009 and September 2014 were collected from a single center. Two hundred sixty-four frames were annotated according to prostate, urethra, ligated plexus, and catheter. Thirty annotated images from different RARP videos were used as a test data set. The dice (similarity) coefficient (DSC) and 95th percentile Hausdorff distance (Hd95) were used to determine model performance. SUL was calculated using the catheter as a reference. Results: The DSC of the best performing model were 0.735 and 0.755 for the catheter and urethra classes, respectively, with a Hd95 of 29.27 and 72.62, respectively. The model performed moderately on the ligated plexus and prostate. The predicted SUL showed a mean difference of 0.64 to 1.86 mm difference vs human annotators, but with significant deviation (standard deviation = 3.28-3.56). Conclusion: This study shows that an AI image segmentation model can predict vital structures during RARP urethral dissection with moderate to fair accuracy. SUL estimation derived from it showed large deviations and outliers when compared with human annotators, but with a small mean difference (<2 mm). This is a promising development for further research on AI-assisted RARP.

Hemodynamical Evaluation of a New Surgically Implanted Pulsatile Right Ventricular Assist Device Driven by a Conventional Intra-Aortic Balloon Pump Console.

Severe right heart failure, often overlooked and challenging to manage, has prompted a growing interest in innovative approaches to provide functional support. This study uses experimentation in large porcine models to introduce a novel prototype of a pulsatile mechanical circulatory support device and document its effects when deployed as a right ventricular assist device (RVAD). The pulsatile ventricular assist platform (pVAP), featuring a membrane pump driven by an intra-aortic balloon pump console, actively generates pulsatile flow to propel right ventricular blood into the pulmonary artery. This novel prototype demonstrates promising potential in addressing the challenges of right heart failure management. After preliminary in vitro assessments, the pVAP was tested on seven porcine models in a healthy state and after the induction of right ventricular failure. During the procedure, a set of standard (ie, standard-of-care) hemodynamic measurements was obtained. Additionally, invasive pressure-volume loop analysis was employed to examine left ventricular hemodynamics. Results indicated that activation of the pVAP during right ventricular failure significantly improved systemic hemodynamics and enhanced left ventricular function. This study sheds light on the potential of the pVAP in managing right heart failure.

Effect of the Lymphocyte Activation Gene 3 Polymorphism rs951818 on Mortality and Disease Progression in Patients with Sepsis-A Prospective Genetic Association Study.

(1) Background: Sepsis is a leading cause of death and a global public health problem. Accordingly, deciphering the underlying molecular mechanisms of this disease and the determinants of its morbidity and mortality is pivotal. This study examined the effect of the rs951818 SNP of the negative costimulatory lymphocyte-activation gene 3 (LAG-3) on sepsis mortality and disease severity. (2) Methods: 707 consecutive patients with sepsis were prospectively enrolled into the present study from three surgical ICUs at University Medical Center Goettingen. Both 28- and 90-day mortality were analyzed as the primary outcome, while parameters of disease severity served as secondary endpoints. (3) Results: In the Kaplan-Meier analysis LAG-3 rs951818 AA-homozygote patients showed a significantly lower 28-day mortality (17.3%) compared to carriers of the C-allele (23.7%, p = 0.0476). In addition, these patients more often received invasive mechanical ventilation (96%) during the course of disease than C-allele carriers (92%, p = 0.0466). (4) Conclusions: Genetic profiling of LAG-3 genetic variants alone or in combination with other genetic biomarkers may represent a promising approach for risk stratification of patients with sepsis. Patient-individual therapeutic targeting of immune checkpoints, such as LAG-3, may be a future component of sepsis therapy. Further detailed investigations in clinically relevant sepsis models are necessary.

TIM-3 Genetic Variants Are Associated with Altered Clinical Outcome and Susceptibility to Gram-Positive Infections in Patients with Sepsis.

Background: Previous studies have reported the fundamental role of immunoregulatory proteins in the clinical phenotype and outcome of sepsis. This study investigated two functional single nucleotide polymorphisms (SNPs) of T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), which has a negative stimulatory function in the T cell immune response. Methods: Patients with sepsis (n = 712) were prospectively enrolled from three intensive care units (ICUs) at the University Medical Center Goettingen since 2012. All patients were genotyped for the TIM-3 SNPs rs1036199 and rs10515746. The primary outcome was 28-day mortality. Disease severity and microbiological findings were secondary endpoints. Results: Kaplan-Meier survival analysis demonstrated a significantly lower 28-day mortality for TIM-3 rs1036199 AA homozygous patients compared to C-allele carriers (18% vs. 27%, p = 0.0099) and TIM-3 rs10515746 CC homozygous patients compared to A-allele carriers (18% vs. 26%, p = 0.0202). The TIM-3 rs1036199 AA genotype and rs10515746 CC genotype remained significant predictors for 28-day mortality in the multivariate Cox regression analysis after adjustment for relevant confounders (adjusted hazard ratios: 0.67 and 0.70). Additionally, patients carrying the rs1036199 AA genotype presented more Gram-positive and Staphylococcus epidermidis infections, and rs10515746 CC homozygotes presented more Staphylococcus epidermidis infections. Conclusion: The studied TIM-3 genetic variants are associated with altered 28-day mortality and susceptibility to Gram-positive infections in sepsis.

Prognostic relevance of hemodialysis for short-term survival in patients after LVAD implantation.

End-stage heart failure (HF) is associated with renal failure (RF). This study aimed to determine the prognostic influence of RF and post-operative hemodialysis on short-term survival following left ventricular assist device (LVAD) implantation. This retrospective study includes 68 patients undergoing LVAD treatment. Kidney function was recorded prior to LVAD implantation, immediately afterwards and after 30 days, noting the need for hemodialysis. Median pre-operative Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) classification was 3.47 ± 1.08. 30 days after implantation there was a significant improvement of estimated glomerular filtration rate (eGFR) and reduction of blood urea nitrogen (BUN). Of pre-operative RF parameters, BUN was associated with increased mortality and need for early post-operative hemodialysis. Post-operative hemodialysis was associated with significantly lower short-term survival, while pre-operative hemodialysis did not impact mortality. Post-operative acute kidney injury (AKI) requiring hemodialysis can be regarded as a strong negative prognostic marker for short-term survival. The absence of a clear correlation between most routine RF parameters and survival or the need for early post-operative hemodialysis calls into question the predictive value of pre-operative RF. The negative association of only post-operative hemodialysis on short-term survival emphasises the impact of the occurrence of AKI.

Short-term ventricular assist device as a bridge to decision in cardiogenic shock: is it a justified strategy?

PURPOSE: Low cardiac output syndrome is associated with significant mortality. In patients with refractory low cardiac output left ventricular assist devices (VAD) are used to re-establish cardiac output and to prevent death. However, long-term LVAD implantation in these is complicated by a high rate of right heart failure and mortality. Therefore, our strategy is to implant a short-term VAD (left or biventricular) as a bridge to decission. METHODS: We retrospectively analysed data from 66 patients who received a short-term LVAD support prior to implantation of a long-term LVAD or HTx between 2003 and 2014. We performed short-term LVAD (CentriMag; Thoratec) implantation via median sternotomy with percutaneous cannulas. Patients were included regardless of perioperative status and severity of heart failure. Patients suffering postcardiotomy cardiogenic shock, receiving isolated RVAD as well as posttransplant patients were excluded from this study. RESULTS: Mean duration of support in the survivor group was 35 ± 25 days versus 25 ± 25 days in the nonsurvivor group (n.s.), range from 1 to 109 days. The overall survival on support was 40 (60%) patients. In the survivor group 12 patients could be successfully weaned from the system, 12 patients received a heart transplant and in 16 a long-term VAD was implanted. In the nonsurvivor group the rate of preoperative extracorporeal life support, the rate of postoperative renal failure and multiorgan failure was significantly higher. CONCLUSIONS: Thanks to its capacity for full ventricular support, short-term univentricular or biventricular LevotronixCentriMag VAD currently represents an ideal solution for bridge-to-decision.

Influence of isoflurane on the diastolic pressure-flow relationship and critical occlusion pressure during arterial CABG surgery: a randomized controlled trial.

The effects of isoflurane on the determinants of blood flow during Coronary Artery Bypass Graft (CABG) surgery are not completely understood. This study characterized the influence of isoflurane on the diastolic Pressure-Flow (P-F) relationship and Critical Occlusion Pressure (COP) during CABG surgery. Twenty patients undergoing CABG surgery were studied. Patients were assigned to an isoflurane or control group. Hemodynamic and flow measurements during CABG surgery were performed twice (15 minutes after the discontinuation of extracorporeal circulation (T15) and again 15 minutes later (T30)). The zero flow pressure intercept (a measure of COP) was extrapolated from a linear regression analysis of the instantaneous diastolic P-F relationship. In the isoflurane group, the application of isoflurane significantly increased the slope of the diastolic P-F relationship by 215% indicating a mean reduction of Coronary Vascular Resistance (CVR) by 46%. Simultaneously, the Mean Diastolic Aortic Pressure (MDAP) decreased by 19% mainly due to a decrease in the systemic vascular resistance index by 21%. The COP, cardiac index, heart rate, Left Ventricular End-Diastolic Pressure (LVEDP) and Coronary Sinus Pressure (CSP) did not change significantly. In the control group, the parameters remained unchanged. In both groups, COP significantly exceeded the CSP and LVEDP at both time points. We conclude that short-term application of isoflurane at a sedative concentration markedly increases the slope of the instantaneous diastolic P-F relationship during CABG surgery implying a distinct decrease with CVR in patients undergoing CABG surgery.

Use of PTFE patch for pericardial closure after minimal invasive LVAD implantation.

The left ventricular assist device (LVAD) is now a routine therapy for advanced heart failure. The thoracotomy approach for LVAD implantation, in which the left ventricle is approached through a pericardial rent, is becoming popular. We demonstrate closure of the pericardial rent with a polytetrafluoroethylene (PTFE) patch and its advantages.

Modified technique using Novalung as bridge to transplant in pulmonary hypertension.

Patients with idiopathic pulmonary artery hypertension in refractory right ventricular failure may decompensate acutely and die while on the lung transplantation waiting list. We describe such a patient bridged to lung transplantation with a modified surgical technique for left pulmonary artery-to-left atrium bypass using Novalung, a low-resistance diffusion membrane device.

Left ventricular assist device implantation with concomitant left ventricular reconstruction without patchplasty.

In this case report, we describe a 66-year-old patient with a massive LV aneurism which resulted after myocardial infarction. Due to severe LV function impairment, it was decided to perform left ventricular reconstruction surgery and, at the same time, left ventricular assist device implantation as a bridge to transplantation. The entire procedure was completed without using any patch material. The patient had an uneventful recovery and was discharged home after 18 days. After 1-year follow-up no adverse events were observed.

De novo aortic regurgitation after continuous-flow left ventricular assist device implantation.

BACKGROUND: Significant aortic regurgitation (AR) after continuous-flow left ventricular assist device (cf-LVAD) placement affects device performance and patient outcomes. This study examined the development of AR and long-term results after implantation of cf-LVADs. METHODS: The study included all patients with no or less than mild AR who underwent HeartMate II (58 [62%]; Thoratec Corp, Pleasanton, CA) or HeartWare (35 [38%]; HeartWare International, Framingham, MA) implantation at our institute from July 2006 to July 2012. Serial echocardiograms were obtained preoperatively, at 1, 3 and 6 months postoperatively, and then at a minimum of 4-month intervals in patients with longer-term support. Kaplan-Meier estimates for freedom from moderate or greater AR were generated. Logistic regression analysis was used to define independent predictors of AR after cf-LVAD implantation. RESULTS: Median duration of LVAD support was 527 days (25(th), 75(th): 289, 907; range, 60 to 2,433 days). Mild AR developed in 48 patients (51.6%) over a median duration of 126 days, with progression to moderate AR in 13 (14%) over 493 days and to severe AR in 2 (2.1%) over 1,231 days. The incidence of mild or greater AR was 43.1% in HeartMate II vs 65.7% in HeartWare recipients (p = 0.035). Overall freedom from moderate or greater AR was 94.7% ± 2.6% at 1 year, 86.9% ± 4.5% at 2 years, 82.8% ± 5.9% at 3 years, and 31% ± 16.9% at 4 years. Independent predictors of AR were duration of support (odds ratio, 1.002; 95% confidence interval, 1.000 to 1.004; p = 0.017) and a persistently closed aortic valve (odds ratio, 0.193; 95% confidence interval, 0.097 to 0.382; p < 0.001). CONCLUSIONS: AR is associated with longer cf-LVAD support duration and persistent aortic valve closure. Incidence of moderate or greater AR after cf-LVAD implantation increases significantly after 3 years. The clinical implications of these data may warrant consideration of prophylactic aortic valve replacement at the time of cf-LVAD implantation, particularly with expected longer duration of support and in patients with preexisting AR that is more than mild.

Lung transplantation from donors outside standard acceptability criteria--are they really marginal?

Lung transplantation (LTx) from "extended donor criteria" donors may reduce significantly organ shortage. However, its influence on results remains unclear. In this study, we evaluate retrospectively the results of LTx from donors outside standard criteria: PaO2/FiO2 ratio < 300 mmHg, age over 55 years, and history of smoking > 20 pack-years. Two hundred and forty-eight patients underwent first time LTx in our institution between January 2007 and January 2013. Seventy-nine patients (Group I) received organs from "extended donor criteria" and 169 patients (Group II) from "standard donor criteria." Recipients' and donors' demographics, perioperative variables, and outcome were compared. Donors from Group I were significantly older [median (interquartile range)]: 52.5 (44;58) vs. 42 (28.5;48.5) years (P < 0.001) with lower PaO2/FiO2 ratio: 366 ± 116.1 455 ± 80.5 mmHg (P < 0.001), higher incidence of smoking history: 57.7% vs. 41.8% (P = 0.013), and more extensive smoking history: 24(15;30) vs. 10(3.75;14) pack-years (P < 0.001). Other parameters were comparable. Recipients' gender, diagnosis, percentage of patients operated on pump and receiving double LTx were also comparable. Recipients from Group I were significantly older: 50 (42;57) vs. 44 (29.5;53.5) years (P = 001). There were no differences observed in recipients' prevalence of primary graft dysfunction (PGD) grade 3 over first three postoperative days, duration of mechanical ventilation, intensive care and hospital length of stay, prevalence of rejection, and bronchiolitis obliterans syndrome (BOS). 90-day, 1-year, and 5-year survival (Group I vs. II) were also similar: 88.6% vs. 91.7%, 83.2% vs. 84.6%, and 59% vs. 68.2% (log rank P = 0.367). Carefully selected donor lungs from outside the standard acceptability criteria may expand existing donor pool with no detrimental effect on LTx outcome.

Use of Foley catheter for insertion of ventricular assist device inflow cannula.

Ventricular assist devices are fast becoming an accepted alternative to treat end-stage heart failure, and are being implemented as a bridge to myocardial recovery, a bridge to heart transplantation, or as destination therapy. Positioning of the inflow cannula into the apex of the ventricle is a crucial step due to the risk of sucking in air. We describe an improved method of preparing the insertion site for the ventricular assist device inflow cannula, to minimize the chances of air embolism and blood spillage, which we applied in a 34-year-old man, as a bridge to transplantation.

Short-term ventricular assist device in post-cardiotomy cardiogenic shock: factors influencing survival.

Post-cardiotomy cardiogenic shock (PCCS) results in substantial morbidity and mortality, whereas refractory cases require mechanical circulatory support. The aim of this study was to evaluate factors influencing survival during short-term ventricular assist support in PCCS. In total, 154 CentriMag(®) (Thoratec; CA, USA) devices were implanted for cardiogenic shock between 2004 and 2011 out of which 31 were for PCCS. A retrospective review was performed in 31 PCCS patients who required the CentriMag short-term VAD as a bridge to decision. Survivors and non-survivors were compared with respect to pre- and intra-operative characteristics as well as duration of short-term VAD support. Mean duration of support was 11.7 ± 15.4 days (range 1-65 days). Seventeen (54.83 %) patients died on support, 14 (45.16 %) were weaned off or upgraded to long-term device, while 11 (35.5 %) were discharged home. The overall survival to myocardial recovery and device explantation, or upgrade to a long-term VAD, was 41.9 % (n = 13) at the study cutoff. EuroSCORE II was significantly higher in non-survivors as compared to survivors (p = 0.047). The duration of short-term VAD support was significantly longer in survivors (p < 0.001). The CentriMag is a versatile, safe and effective short-term circulatory support for patients with PCCS as a bridge to decision which enables longer support and better recovery of both heart and end-organ function and thus may improve the survival of PCCS patients. Lower EuroSCORE may be essential for myocardial recovery in PCCS.

The regulatory toll-like receptor 4 genetic polymorphism rs11536889 is associated with renal, coagulation and hepatic organ failure in sepsis patients.

BACKGROUND: Toll-like receptor 4 (TLR4), a lipopolysaccharide (LPS) receptor complex signal-transducing molecule, plays a crucial role in sensing LPS from gram-negative bacteria. TLR4 signaling pathway activation by LPS plays a major role in sepsis pathogenesis. A single nucleotide polymorphism, rs11536889, in the 3'-untranslated region of the TLR4 gene is thought to affect TLR4 translation. This study aimed to investigate whether organ failure in sepsis patients is related to the TLR4 rs11536889 genotype. METHODS: Adult Caucasian patients with sepsis from the intensive care unit of a university medical center were followed up for 90 days, and organ failure was recorded as the primary outcome variable. Blood samples were collected at enrollment for TLR4 rs11536889 genotyping. Sepsis-related organ failure assessment (SOFA) scores were quantified at sepsis onset and throughout the observational period to monitor organ failure. RESULTS: A total of 210 critically ill patients with sepsis were enrolled into this study. Wild-type GG was compared to GC/CC. During their stay in the intensive care unit, GG patients presented significantly higher SOFA scores than did C allele carriers (7.9 ± 4.5 and 6.8 ± 4.2, respectively; p = 0.0005). Analysis of organ-specific SOFA sub-scores revealed significant differences in three organ systems: renal, coagulation and hepatic (p = 0.0005, p = 0.0245 and p < 0.0001, respectively). Additionally, the rs11536889 polymorphism was associated with a higher incidence of gram-negative infections. CONCLUSIONS: These results offer the first evidence that TLR4 rs11536889 is a useful marker of organ failure in patients with sepsis.

Distal limb perfusion: Achilles' heel in peripheral venoarterial extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation (ECMO) is a temporary mechanical circulatory assist method that offers circulatory as well as respiratory support efficiently via peripheral access; however, it is liable to complications. Limb ischemia is one of the notorious complications of ECMO but can be avoided utilizing a proper distal limb perfusion method. A retrospective study of patients undergoing peripheral venoarterial (VA) ECMO for various reasons between June 2010 and December 2012 was performed. All patients were evaluated by our multidisciplinary team for suitability as candidates for ECMO. A peripheral VA-ECMO circuit was implanted via groin: inflow cannula in the femoral vein, an outflow cannula and distal-perfusion cannula, or an introducer sheath in the femoral artery. During the study period, 83 patients underwent various types of ECMO; 45 received peripheral VA-ECMO. Distal limb perfusion was achieved with an introducer sheath (6-8 Fr) in 13 cases and with a distal-perfusion cannula (10-12 Fr) in 32 cases. Nine (20%) patients developed signs of ischemia; five (11.2%) were treated conservatively, while four (8.8%) required surgical intervention. One patient required a below-knee amputation. The incidences of limb ischemia and limb ischemia requiring surgical intervention were significantly higher for the introducer sheath compared with the cannula (30.6 vs. 15.6% and 15.4 vs. 6.25%, respectively). Moreover, the patients supported on ECMO with a distal-perfusion cannula spent a significantly longer time on ECMO compared with the ones in whom an introducer sheath was used (11.9 ± 9.1 vs. 7.7 ± 4.3 days). The mean cannula size was significantly greater than the mean introducer sheath size (11.1 ± 1.3 vs. 7.0 ± 1.1 Fr). Use of a distal-perfusion cannula is a most reliable method of limb perfusion in peripheral VA-ECMO. The cannula can ensure adequate and smooth perfusion of the limb owing to its large caliber, its less turbulent flow, the ability it provides to monitor the flow, and the option to attach a side port.