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71.
Kevin Hodges Carlos Godoy Rivas José Aguilera Robert Borden Alaa Alashi Eugene H. Blackstone Milind Y. Desai Nicholas G. Smedira 《The Journal of thoracic and cardiovascular surgery》2019,157(6):2289-2299
ObjectivesThis study evaluates operative approach and contemporary surgical outcomes in the management of left ventricular outflow tract obstruction by a single surgeon at a high-volume, specialized hypertrophic cardiomyopathy center.MethodsThis is a retrospective review of 1559 consecutive operations for left ventricular outflow tract obstruction from 2005 to 2015. Demographic profiles, echocardiogram-derived ventricular morphology and hemodynamics, operative data, and in-hospital outcomes were analyzed.ResultsOf the 1559 operations, 586 were isolated septal myectomies, 522 were myectomies with mitral valve or subvalvular apparatus intervention, 422 were myectomies with another concomitant procedure, and 29 were isolated mitral valve interventions without myectomy. Common mitral valve interventions included anterior leaflet shortening (16%), chordae tendineae resection (9.8%), papillary muscle resection (7.2%), and papillary muscle reorientation (7.5%). Ninety-two patients underwent mitral valve replacement, 42 for left ventricular outflow tract obstruction and 50 for intrinsic mitral valve pathology. Patients undergoing mitral interventions had thinner septums (18 ± 0.4 mm vs 22 ± 0.5 mm, P < .001) and less myocardium removed (6.2 ± 3.5 g vs 8.8 ± 3.8 g, P < .001) than patients without a mitral intervention. Prevalence of in-hospital permanent pacemaker insertion was 4.2% (n = 1334) for complete heart block and 1.1% (n = 464) for isolated septal myectomy with normal preoperative conduction. Overall, there were 2 postoperative ventricular septal defects (0.13%) and none for isolated myectomies. Operative mortality was 0.38%.ConclusionsSeptal myectomy can be performed safely with excellent outcomes when the procedure is performed by a highly experienced surgeon in a high-volume, specialized center. A mitral valve intervention is a useful adjunct in patients with moderate hypertrophy. 相似文献
72.
Ketai LH; Williamson MR; Telepak RJ; Levy H; Koster FT; Nolte KB; Allen SE 《Radiology》1994,191(3):665
73.
74.
The relative importance of thrombin inhibition and factor Xa inhibition to the antithrombotic effects of heparin 总被引:4,自引:1,他引:4
The relative importance of antithrombin and anti-factor Xa activities of heparin fractions required to achieve optimal antithrombotic effects is unknown. To study this, we measured the effects of standard heparin, an octasaccharide heparin fraction (anti-factor Xa activity only), and dermatan sulfate (antithrombin activity only) on the prevention of thrombosis and related this to their anticoagulant effects in vivo in rabbits. Thrombosis was measured as the incorporation of 125I- fibrinogen into tissue thromboplastin-induced thrombi using a Wessler- type model. Ex vivo changes in thrombin clotting time (TCT) were used as an index of antithrombin activity, and a chromogenic anti-factor Xa assay was used to measure anti-factor Xa activity. In addition, the ability of the three sulfated polysaccharides to simultaneously inhibit the generation of thrombin activity and to enhance the inactivation of the factor Xa added to initiate thrombin generation in plasma was determined. Standard heparin, in a dose of 10 anti-factor Xa U/kg, inhibited thrombus formation by 90%, prolonged the TCT by two seconds, and resulted in an anti-factor Xa level of 0.32 U/mL. The octasaccharide heparin fraction, in a dose of 10 anti-factor Xa U/kg, inhibited thrombus formation by 41%, had no effect on the TCT, and resulted in an anti-factor Xa level of 0.28 U/mL. Higher doses of the octasaccharide resulted in a further increase in the anti-factor Xa levels but had no further effect on thrombus formation. Dermatan sulfate, in a dose of 500 micrograms/kg, inhibited thrombus formation by 95%, but had no affect on the TCT. These results indicate that the antithrombotic effect achieved by inhibiting factor Xa is limited and that better antithrombotic effects are achieved by heparin or heparin- like substances capable of influencing the inactivation and/or the generation of thrombin. 相似文献
75.
Ng CK Gill IS Patil MB Hung AJ Berger AK de Castro Abreu AL Nakamoto M Eisenberg MS Ukimura O Thangathurai D Aron M Desai MM 《European urology》2012,61(1):67-74
Background
Robot-assisted and laparoscopic partial nephrectomies (PNs) for medial tumors are technically challenging even with the hilum clamped and, until now, were impossible to perform with the hilum unclamped.Objective
Evaluate whether targeted vascular microdissection (VMD) of renal artery branches allows zero-ischemia PN to be performed even for challenging medial tumors.Design, setting, and participants
A prospective cohort evaluation of 44 patients with renal masses who underwent robot-assisted or laparoscopic zero-ischemia PN either with anatomic VMD (group 1; n = 22) or without anatomic VMD (group 2; n = 22) performed by a single surgeon from April 2010 to January 2011.Intervention
Zero-ischemia PN with VMD incorporates four maneuvers: (1) preoperative computed tomographic reconstruction of renal arterial branch anatomy, (2) anatomic dissection of targeted, tumor-specific tertiary or higher-order renal arterial branches, (3) neurosurgical aneurysm microsurgical bulldog clamp(s) for superselective tumor devascularization, and (4) transient, controlled reduction of blood pressure, if necessary.Measurements
Baseline, perioperative, and postoperative data were collected prospectively.Results and limitations
Group 1 tumors were larger (4.3 vs 2.6 cm; p = 0.011), were more often hilar (41% vs 9%; p = 0.09), were medial (59% and 23%; p = 0.017), were closer to the hilum (1.46 vs 3.26 cm; p = 0.0002), and had a lower C index score (2.1 vs 3.9; p = 0.004) and higher RENAL nephrometry scores (7.7 vs 6.2; p = 0.013). Despite greater complexity, no group 1 tumor required hilar clamping, and perioperative outcomes were similar to those of group 2: operating room time (4.7 and 4.1 h), median blood loss (200 and 100 ml), surgical margins for cancer (all negative), major complications (0% and 9%), and minor complications (18% and 14%). The median serum creatinine level was similar 2 mo postoperatively (1.2 and 1.3 mg/dl). The study was limited by the relatively small sample size.Conclusions
Anatomic targeted dissection and superselective control of tumor-specific renal arterial branches facilitate zero-ischemia PN. Even challenging medial and hilar tumors can be excised without hilar clamping. Global surgical renal ischemia has been eliminated for most patients undergoing PN at our institution. 相似文献76.
PURPOSE: Venous involvement develops in 5% to 10% of patients with renal cell carcinoma and is generally considered a relative contraindication to laparoscopic radical nephrectomy. To our knowledge we report the initial clinical series of laparoscopic radical nephrectomy for renal cell carcinoma associated with level I renal vein thrombus. MATERIALS AND METHODS: At our 2 institutions 8 patients each underwent laparoscopic radical nephrectomy for level I microscopic renal vein thrombus (group 1) and level I gross thrombus (group 2). In all 8 group 2 patients the level I thrombus was preoperatively diagnosed by computerized tomography. Mean renal tumor size in groups 1 and 2 was 7.8 and 12.4 cm., respectively. After controlling the renal artery the renal vein was secured by firing an endoscopic gastrointestinal anastomosis stapler on its collapsed, uninvolved proximal part adjacent to the vena cava. Intraoperative, postoperative and pathological parameters were assessed in the 2 groups. RESULTS: In group 1 laparoscopic radical nephrectomy was technically successful in all 8 patients. Mean operative time was 3.1 hours, mean estimated blood loss was 382 cc and mean hospital stay was 1.9 days. In 1 patient each a soft tissue and a vascular margin was positive for cancer. At a mean follow up of 19.5 months (range 2 to 36) metastatic disease occurred in 3 cases (38%). In group 2 laparoscopic radical nephrectomy was technically successful in 7 cases with open conversion in 1. Mean operative time was 3.3 hours, mean estimated blood loss was 354 cc and mean hospital stay was 2.3 days. Surgical soft tissue and the renal vein vascular margin of the transected vein were negative for cancer in all 8 cases. At a mean followup of 9.4 months (range 5 to 16) pulmonary metastasis developed in 1 patient (13%). CONCLUSIONS: Although it is an advanced procedure, laparoscopic radical nephrectomy in patients with level I renal vein thrombus is feasible, safe and follows established oncological principles. 相似文献
77.
Desai MM Gill IS Carvalhal EF Kaouk JH Banks K Raju R Raja SS Meraney AM Sung GT Sauer J 《Journal of endourology / Endourological Society》2002,16(7):431-443
BACKGROUND AND PURPOSE: Despite a 10% to 15% failure rate, endopyelotomy remains the treatment of choice for most patients with ureteropelvic junction (UPJ) obstruction. We present a novel technique of percutaneous endopyeloplasty, wherein a precise, full-thickness approximation of a standard longitudinal endopyelotomy incision is performed in a horizontal Heineke-Mikulicz fashion through the conventional solitary percutaneous tract via a nephroscope. We assess the feasibility and efficacy of percutaneous endopyeloplasty in a chronic porcine bilateral UPJ obstruction model and compare outcome data with those#10; of conventional endopyelotomy and laparoscopic pyeloplasty. MATERIALS AND METHODS: Partial UPJ obstruction was created in 20 kidneys (11 pigs) by laparoscopic ligation of the upper ureter over a 5F ureteral catheter. After development of hydronephrosis over a period of 4 to 6 weeks, percutaneous endopyeloplasty (N = 10), conventional percutaneous endopyelotomy (N = 5), or laparoscopic pyeloplasty (N = 5) was performed. The essential steps of percutaneous endopyeloplasty include retrograde ureteral catheterization, standard percutaneous endopyelotomy incision, mobilization of the distal ureteral lip, horizontal suturing of the endopyelotomy incision through the nephroscope, and nephrostomy drainage and ureteral stenting. Suturing was performed using a modified 5-mm laparoscopic device (Sew Right 5 SR; LSI Solutions, Rochester, NY), which was passed through the nephroscope. RESULTS: Percutaneous endopyeloplasty was technically successful in all 10 kidneys with a mean total operative time of 81.4 minutes (range 51-117 minutes). The mean endopyeloplasty suturing time was 29.4 minutes (range 20-64 minutes). Three kidneys required two sutures, while seven kidneys required three sutures to complete the endopyeloplasty. The solitary complication was a lower-pole infundibular stenosis. Over a mean follow-up of 7.7 weeks, all renal units showed relief of obstruction, as evidenced by regression of hydronephrosis,#10; improvement in T(1/2) and glomerular filtration rate on renogram, and a low intrapelvic pressure on Whitaker test. At autopsy, the endopyeloplasty site showed a fine, well-healed transverse scar with no evidence of residual suture on the mucosal surface. The mean caliber of the UPJ following endopyeloplasty (13.8F +/- 2.2F) was significantly greater (P = 0.01) than that following endopyelotomy (7.5F +/- 1.9F). Intraoperative extravasation on completion of endopyeloplasty was absent (N = 6) or mild (N = 4) compared with that seen in all five kidneys following endopyelotomy. CONCLUSION: Percutaneous endopyeloplasty is feasible, simple, reproducible, and effective. Its advantages over conventional endopyelotomy include transrenal performance of a Fenger-plasty, wider caliber of the UPJ, absence of extravasation, and shorter duration of ureteral stenting. 相似文献
78.
MR Danzig RA Ghandour P Chang AA Wagner PM Pierorazio ME Allaf JM McKiernan 《Urologic oncology》2017,35(3):116
Purpose
We compared renal function outcomes among patients in the surveillance and intervention arms of the DISSRM registry.Materials and methods
Patients were grouped into chronic kidney disease stages by estimated glomerular filtration rate range. Cases were considered up staged if a more advanced chronic kidney disease stage was entered during followup. Chronic kidney disease up staging-free survival was compared among groups using Kaplan-Meier analysis and paired comparisons log rank tests. Multivariate Cox regression identified independent predictors of chronic kidney disease up staging-free survival.Results
A total of 162 patients met the study inclusion criteria, with 68 in the surveillance arm, 65 undergoing partial nephrectomy, 15 undergoing radical nephrectomy, and 14 undergoing cryoablation. Median tumor size was 2.2 cm. Mean estimated glomerular filtration rate change was significantly larger for radical nephrectomy vs. surveillance (?9.2 vs. ?0.5 ml/min/1.73 m2) and for radical vs. partial nephrectomy (?9.2 vs. ?1.9 ml/min/1.73 m2) (P = 0.001). No other groups differed significantly. On Kaplan-Meier analysis, patients undergoing radical nephrectomy had significantly worse chronic kidney disease up staging-free survival vs. those treated with partial nephrectomy (P = 0.029), surveillance (P = 0.007), and cryoablation (P = 0.019). No other groups differed significantly. On multivariate analysis, radical nephrectomy independently predicted poor chronic kidney disease up staging-free survival (odds ratio vs. surveillance 30.6, P = 0.001). Neither partial nephrectomy (P = 0.985) nor cryoablation (P = 0.976) predicted poor chronic kidney disease up staging-free survival relative to surveillance.Conclusions
Patients in the surveillance arm had superior estimated glomerular filtration rate preservation compared to those in the radical nephrectomy but not the partial nephrectomy arm. In certain patients with small renal masses, surveillance and partial nephrectomy may offer comparable renal functional outcomes. This could be partly attributable to a modest estimated glomerular filtration rate decrease associated with surveillance itself. A thorough understanding of the renal functional impacts of treatment modalities is critical in the management of small renal masses. 相似文献79.
Proshad N. Efune Matthew J. Hoyt Rita Saynhalath Chul Ahn Matthew F. Pearsall Umar H. Khan Thomas Feehan Dev M. Desai Peter Szmuk 《Paediatric anaesthesia》2023,33(9):754-764
Introduction
Fluid administration is an important aspect of the management of children undergoing liver transplantation and may impact postoperative outcomes. Our aim was to evaluate the association between volume of intraoperative fluid administration and our primary outcome, the duration of postoperative mechanical ventilation following pediatric liver transplantation. Secondary outcomes included intensive care unit length of stay and hospital length of stay.Methods
We conducted a multicenter, retrospective cohort study using electronic data from three major pediatric liver transplant centers. Intraoperative fluid administration was indexed to weight and duration of anesthesia. Univariate and stepwise linear regression analyses were conducted.Results
Among 286 successful pediatric liver transplants, the median duration of postoperative mechanical ventilation was 10.8 h (IQR 0.0, 35.4), the median intensive care unit length of stay was 4.3 days (IQR 2.7, 6.8), and the median hospital length of stay was 13.6 days (9.8, 21.1). Univariate linear regression showed a weak correlation between intraoperative fluids and duration of ventilation (r2 = .037, p = .001). Following stepwise linear regression, intraoperative fluid administration remained weakly correlated (r2 = .161, p = .04) with duration of postoperative ventilation. The following variables were also independently correlated with duration of ventilation: center (Riley Children's Health versus Children's Health Dallas, p = .001), and open abdominal incision after transplant (p = .001).Discussion
The amount of intraoperative fluid administration is correlated with duration of postoperative mechanical ventilation in children undergoing liver transplantation, however, it does not seem to be a strong factor.Conclusions
Other modifiable factors should be sought which may lead to improved postoperative outcomes in this highly vulnerable patient population. 相似文献80.
K. Venkat M. Desai M. M. Arora P. Singh M. I. Khatkhatay 《Osteoporosis international》2009,20(6):955-962
Summary Age-related changes in sex steroid levels and its contribution to variations in rate of bone loss among men is unclear. Although,
Bio-T and Bio-E2 levels declined with age and depicted an association with BMD in healthy Indian men, Bio-E2 was found to be an independent predictor of BMD.
Introduction Ethnicity influences sex steroid levels, therefore, their role in pathogenesis of low bone mass needs to be established in
various populations. We assessed the extent of changes in sex steroid levels with age and related these to bone mineral density
(BMD) in healthy Indian men.
Methods Total testosterone (TT), estradiol (E2), sex hormone-binding globulin (SHBG), PTH, osteocalcin (OC), and c-terminal telopeptide (CTX) were measured in 330 men aged
20–55 years and correlated with BMD measured by DXA.
Results Both Bio-T (1% per year) and Bio-E2 (0.8% per year) levels decreased significantly in ageing men, whereas TT (0.4% per year) and E2 (0.3% per year) levels decreased only marginally with age. In contrast, SHBG (1.4% per year) and PTH (1% per year) levels
increased significantly with age. Serum TT (r = 0.19, p = 0.01) and Bio-T (r = 0.2, p = 0.01) levels were associated positively with BMD at spine, whereas E2 and Bio-E2 levels were associated with BMD at spine [E
2 (r = 0.31, p < 0.0001); Bio-E2
r = 0.37, p < 0.0001] and femur (E2
r = 0.26, p = 0.001; Bio-E2
r = 0.27, p = 0.001). Men in the lowest quartile of Bio-E2 were associated with lower BMD and higher bone turnover.
Conclusions Age-related decrease in bioavailable sex steroid levels is associated with BMD in healthy Indian men. Bio-E2 was found to be an independent predictor of BMD. 相似文献