The contributions of changes in primary systolic and diastolic properties, limitations of contractile reserve, and alterations in energy efficiency to the left ventricular dysfunction seen with chronic pacing tachycardia were investigated. Seven dogs (heart failure group) were ventricularly paced at 250 beats per minute for 26.3 ±2.9 days and compared with a separate control group (n =8). Studies were performed with isolated, metabolically supported hearts coupled to a computer-controlled loading system. Pressurevolume relations and myocardial oxygen consumption (MVo2) were measured to assess chamber systolic and diastolic properties and efficiency (relation between MVo2 and pressure-volume area [PVA] significantly larger (33.3±3.9 versus 21.9±7.6 ml,p<0.01). Inotropic response to increased heart rate and exogenous ,-adrenergic stimulation (dobutamine HCI) was significantly impaired in failure compared with control hearts. Most interestingly, failure hearts had a lowered slope of the MVo2-PVA relation (2.1±1.1 versus 2.9±1.4 ml 02 mm Hg-' * ml-l * 100 g left ventricle-', p<0.001), indicating increased effliciency of chemomechanical energy conversion. The y intercept of the MVo2-PVA relation, which reflects oxygen costs of basal metabolism and excitation-contraction coupling, was unchanged in the two groups despite decreased contractility of the heart failure hearts. These results demonstrate reduced chamber and myocardial contractility, dilatation without alteration of passive myocardial properties, impaired contractile reserve, and novel alterations in cardiac efficiency in this model of heart failure. (Circulation Research 1992;70:516- performance from chronic rapid pacing, the mechanisms underlying this dysfunction remain poorly characterized. There are several mechanisms definable at a chamber level that could contribute to reduced net pump function. These include 1) primary reductions in chamber and/or myocardial contractility, 2) abnormal diastolic chamber and/or myocardial stiffness, 3) reduced inotropic reserve caused by blunting of the positive force-frequency relation or decreased response to 83-adrenergic stimulation, and 4) a reduced ability to convert consumed oxygen to mechanical work (decreased metabolic efficiency). The purpose of the present study was to determine the contribution of each of these factors to the cardiac failure induced by chronic rapid pacing.To elucidate the role of each of these mechanisms, studies were performed using isolated, metabolically supported canine hearts coupled to a computer-simulated vascular loading system. This preparation offers the advantages of rigid control of chamber load, heart rate, and coronary perfusion and precise measurements of ventricular volume and myocardial oxygen consumption (MVo2). The results demonstrate reductions in chamber and myocardial contractility, ventricular dilaby guest on
BackgroundRobot-assisted radical cystectomy (RARC) with intracorporeal diversion has been shown to be feasible in a few centers of excellence worldwide, with promising functional and oncologic outcomes. However, it remains unknown whether the complexity of the procedure allows its duplication in other non-pioneer centers. We attempt to address this issue by presenting our cumulative experience with RARC and intracorporeal neobladder formation.MethodsWe retrospectively identified 62 RARCs in 50 men and 12 women (mean age 63.6 years) in two tertiary centers. Intracorporeal Studer neobladders were created, duplicating the steps of standard open surgery. Perioperative and postoperative variables and complications were analyzed using standardized tools. Functional and oncological results were assessed.ResultsThe mean operative time was 476.9 min (range, 310 to 690) and blood loss was 385 ml (200 to 800). The mean hospital stay was 16.7 (12 to 62) days with no open conversion. Perioperative complications were grade II in 15, grade III in 11, and grade IV in 5 patients. The mean nodal yield was 22.9 (8 to 46). Positive margins were found in in 6.4%. The 90- and 180-day mortality rates were 0% and 3.3%. The average follow-up was 37.3 months (3 to 52). Continence was achieved in 88% of patients. The cancer-specific survival rate and overall survival rate were 84% and 71%, respectively.ConclusionsA RARC with intracorporeal neobladder creation is safe and reproducible in ‘non-pioneer’ tertiary centers with robotic expertise with acceptable operative time and complications. Further standardization of RARC with intracorporeal diversion is a prerequisite for its widespread use.
CTCs with expression of breast cancer-associated transcripts are present in a considerable proportion of patients with BC. EMT and stem cell-specific transcripts of CTCs correlate with clinical stage and can be detected in patients negative for epithelial transcripts. The prognostic relevance of AdnaTest® results in BC patients and potential implications for therapy decisions remain to be determined in prospective studies.
BackgroundThe role of urine markers in the surveillance of patients with non-muscle invasive bladder cancer (NMIBC) is discussed extensively. In case of negative cystoscopy the additional prognostic value of these markers has not been clearly defined yet. The present study is the first systematic approach to directly compare the ability of a urine marker panel to predict the risk of recurrence and progression in bladder cancer (BC) patients with no evidence of relapse during surveillance for NMIBC.MethodsOne hundred fourteen patients who underwent urine marker testing during surveillance for NMIBC and who had no evidence of BC recurrence were included. For all patients cytology, Fluorescence-in-situ-hybridization (FISH), immunocytology (uCyt+) and Nuclear matrix protein 22 enzyme-linked immunosorbent assay (NMP22) were performed. All patients completed at least 24 months of endoscopic and clinical follow-up of after inclusion.ResultsWithin 24 months of follow-up, 38 (33.0%) patients experienced disease recurrence and 11 (9.8%) progression. Recurrence rates in patients with positive vs. negative cytology, FISH, uCyt+ and NMP22 were 52.6% vs. 21.9% (HR = 3.9; 95% CI 1.75-9.2; p < 0.001), 47.6% vs. 25.0% (HR 2.7; 1.2-6.2; p = 0.01), 43.8% vs. 22.4% (HR 3.3; 1.5-7.6; p = 0.003) and 43.8% vs. 16.7% (HR 4.2; 1.7-10.8; p = 0.001). In patients with negative cytology, a positive NMP22 test was associated with a shorter time to recurrence (p = 0.01), whereas FISH or uCyt+ were not predictive of recurrence in these patients. In the group of patients with negative cytology and negative NMP22, only 13.5% and 5.4% developed recurrence and progression after 24 months.ConclusionsPatients with positive urine markers at time of negative cystoscopy are at increased risk of recurrence and progression. In patients with negative cytology, only NMP22 is predictive for recurrence. Patients with negative marker combinations including NMP22 harbour a low risk of recurrence. Therefore, the endoscopic follow-up regimen may be attenuated in this group of patients.
In recent years, robot-assisted radical cystectomy (RARC) has shown similar oncologic outcomes compared with the gold standard open radical cystectomy with the added benefit of less blood loss and shorter hospital stay. Robot-assisted cystectomy with intracorporeal ileal neobladder is a complex surgical procedure and is usually performed in centers with experienced surgeons. We propose robot-assisted cystectomy with intracorporeal neobladder using the Y pouch previously described in open radical cystectomy. We think that the Y pouch is easier to perform than conventional spherical pouches without compromising functional outcomes. It may therefore be a good alternative for patients undergoing RARC with intracorporeal diversion.
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