A meta-analysis on the effect of proximal landing zone location on stroke and mortality in thoracic endovascular aortic repair.

BACKGROUND: Thoracic endovascular aortic repair (TEVAR) involving the aortic arch may increase the opportunity for stroke owing to disruption of cerebral circulation and embolization. In this study, a systematic meta-analysis was performed to examine the impact of proximal landing zone location on stroke and 30-day mortality after TEVAR. METHODS: MEDLINE and Cochrane Library were searched for all original studies of TEVAR reporting outcomes of stroke or 30-day mortality for at least two adjacent proximal landing zones, based on the Ishimaru classification scheme. Forest plots were created using relative risks (RR) with 95% confidence intervals (CI). An I2 of <40% was regarded as minimal heterogeneity. A P value of <.05 was considered significant. RESULTS: Of the 57 studies examined, a total of 22,244 patients (male 73.1%, aged 71.9 ± 11.5 years) were included in the meta-analysis, with 1693 undergoing TEVAR with proximal landing zone 0, 1931 with zone 1, 5839 with zone 2, and 3089 with zone 3 and beyond. The overall risk of clinically evident stroke was 2.7% for zones ≥3, 6.6% for zone 2, 7.7% for zone 1, and 14.2% for zone 0. More proximal landing zones were associated with higher risks of stroke compared with distal (zone 2 vs ≥3: RR, 2.14; 95% CI, 1.43-3.20; P = .0002; I2 = 56%; zone 1 vs 2: RR, 1.48; 95% CI, 1.20-1.82; P = .0002; I2 = 0%; zone 0 vs 1: RR, 1.85; 95% CI, 1.52-2.24; P < .00001; I2 = 0%). Mortality at 30 days was 2.9% for zones ≥3, 2.4% for zone 2, 3.7% for zone 1, and 9.3% for zone 0. Zone 0 was associated with higher mortality compared with zone 1 (RR, 2.30; 95% CI, 1.75-3.03; P < .00001; I2 = 0%). No significant differences were found in 30-day mortality between zones 1 and 2 (P = .13) and between zone 2 and zones ≥3 (P = .87). CONCLUSIONS: The risk of stroke from TEVAR is lowest in zone 3 and beyond, increasing significantly as the landing zone is moved proximally. Furthermore, perioperative mortality is increased with zone 0 compared with zone 1. Therefore, risk of stent grafting in the proximal arch should be weighed against alternative surgical or nonoperative options. It is anticipated that the risk of stroke will improve with further development of stent graft technology and implantation technique.

Interposition Technique for Pulmonary Valve Replacement.

BACKGROUND: Stented bioprosthesis implant at surgical pulmonary valve replacement (PVR) ideally should be 25 to 27 mm to facilitate future percutaneous PVR. This often requires accommodating 35 to 37 mm diameter sewing ring in the pulmonary position and requires anterior patch augmentation of the right ventricular outflow tract (RVOT). We present a novel "interposition" technique of PVR that allows upsizing the valve without RVOT patch augmentation. METHODS: Using standard cardiopulmonary bypass, the main pulmonary artery (MPA) is dissected and transected at an appropriate level. The remnants of pulmonary valve leaflets are excised. The valve stent posts are telescoped into distal MPA, the MPA continuity is restored by end-to-end anastomosis of the proximal and distal MPA, with the interposed prosthetic valve sewing ring in the suture line between the two edges of the MPA with the bulk of the sewing ring extravascular. RESULT: A total of seven patients (tetralogy of Fallot, three; congenital pulmonary stenosis, four; age range: 15-33 years) underwent the procedure. No patient required RVOT patch augmentation, all patients were extubated in the operating room and were fast-tracked to recovery. Our proposed technique of PVR has the following advantages: accommodate larger size valve, eliminates risk of a paravalvar leak, coronary compression, and anterior tilting of the prosthesis. CONCLUSION: The valve interposition technique avoids the need for RVOT patch, allows implantation of an adequate sized prosthetic valve, maintains native geometry of the pulmonary artery without the risk of tilting of the prosthesis, and eliminates the risk of paravalvular regurgitation and left coronary compression.

Modified Warden Operation With the Use of Femoral Vein Homograft for Repair of a Variant of Right-Sided Partial Anomalous Pulmonary Venous Connection.

Surgical repair of right-sided partial anomalous pulmonary venous return (PAPVR) involves baffling the pulmonary vein across a naturally occurring or surgically created atrial septal defect without causing pulmonary venous or superior vena cava obstruction. A nine-year-old male presented to us with an unusual anatomical variant of right-sided partial anomalous pulmonary venous connection. The pulmonary veins draining the right upper and middle lobes connected to the azygous vein that drained in the usual fashion into the superior vena cava. The Warden operation was modified, with the use of femoral vein homograft, to avoid pulmonary venous obstruction.

Human Neonatal Thymus Mesenchymal Stem/Stromal Cells and Chronic Right Ventricle Pressure Overload.

Right ventricle (RV) failure secondary to pressure overload is associated with a loss of myocardial capillary density and an increase in oxidative stress. We have previously found that human neonatal thymus mesenchymal stem cells (ntMSCs) promote neovascularization, but the ability of ntMSCs to express the antioxidant extracellular superoxide dismutase (SOD3) is unknown. We hypothesized that ntMSCs express and secrete SOD3 as well as improve survival in the setting of chronic pressure overload. To evaluate this hypothesis, we compared SOD3 expression in ntMSCs to donor-matched bone-derived MSCs and evaluated the effect of ntMSCs in a rat RV pressure overload model induced by pulmonary artery banding (PAB). The primary outcome was survival, and secondary measures were an echocardiographic assessment of RV size and function as well as histological studies of the RV. We found that ntMSCs expressed SOD3 to a greater degree as compared to bone-derived MSCs. In the PAB model, all ntMSC-treated animals survived to the study endpoint whereas control animals had significantly decreased survival. Treatment animals had significantly less RV fibrosis and increased RV capillary density as compared to controls. We conclude that human ntMSCs demonstrate a therapeutic effect in a model of chronic RV pressure overload, which may in part be due to their antioxidative, antifibrotic, and proangiogenic effects. Given their readily available source, human ntMSCs may be a candidate cell therapy for individuals with congenital heart disease and a pressure-overloaded RV.

Regenerative Medicine Strategies for Hypoplastic Left Heart Syndrome.

Hypoplastic left heart syndrome (HLHS), the most severe and common form of single ventricle congenital heart lesions, is characterized by hypoplasia of the mitral valve, left ventricle (LV), and all LV outflow structures. While advances in surgical technique and medical management have allowed survival into adulthood, HLHS patients have severe morbidities, decreased quality of life, and a shortened lifespan. The single right ventricle (RV) is especially prone to early failure because of its vulnerability to chronic pressure overload, a mode of failure distinct from ischemic cardiomyopathy encountered in acquired heart disease. As these patients enter early adulthood, an emerging epidemic of RV failure has become evident. Regenerative medicine strategies may help preserve or boost RV function in children and adults with HLHS by promoting angiogenesis and mitigating oxidative stress. Rescuing a RV in decompensated failure may also require the creation of new, functional myocardium. Although considerable hurdles remain before their clinical translation, stem cell therapy and cardiac tissue engineering possess revolutionary potential in the treatment of pediatric and adult patients with HLHS who currently have very limited long-term treatment options.

Intraabdominal partitioning of the laparoscopic sleeve gastrectomy remnant optimizes the specimen extraction ergonomics and postoperative pain and is an attractive technique in teenage patients.

INTRODUCTION: Laparoscopic sleeve gastrectomy (LSG) has become an increasingly popular bariatric procedure in the pediatric population worldwide. The fear of complications, postoperative pain, and recovery remain the reservations for wider application of surgery in morbidly obese children. We present a novel technique for LSG remnant retrieval. MATERIALS AND METHODS: The patient was a 16-year old girl with a body mass index of 55 kg/m(2) and significant comorbidities who underwent LSG and liver biopsy. In the extraction technique, a specimen containing the gastric body and fundus, approximately 80% of the stomach volume, was partitioned longitudinally and intracorporeally with endoshears; subsequently, it was retrieved in one fragment via the lumen of a 15-mm port. RESULTS: The procedure time was 65 minutes (specimen extraction time was 7 minutes). Her recovery was uneventful, and she was discharged home on the second postoperative day. At the 1-, 3-, and 6-month follow-up, she has shown all the benefits of weight loss and associated improvement in metabolic parameters and quality of life, without any complications. CONCLUSIONS: This technique for gastric remnant retrieval results in minimizing postoperative pain, reducing operative costs, and minimizing the likelihood of wound infection.

Impact of regional versus general anesthesia on the clinical outcomes of patients undergoing major lower extremity amputation.

BACKGROUND: Patients undergoing major lower extremity amputation (MLEA) for peripheral arterial disease are often elderly, debilitated, and fraught with medical comorbid conditions that place them at high risk for surgical intervention. Data from lower extremity revascularization surgeries are often extrapolated to determine which anesthetic modality to use for amputations, with preference given to regional anesthesia. However, there is little evidence to support the use of one mode of anesthesia over another. We conducted this study to determine the effect of anesthetic modality on the clinical outcomes of patients undergoing above- or below-knee amputations. METHODS: This study is a retrospective review of consecutive patients who underwent MLEA at a single center between 2002-2011. The study population was divided into 2 groups based on anesthetic modality (i.e., regional vs. general anesthesia). These groups were compared based on demographics and comorbidities. Major outcomes analyzed included death, myocardial infarction (MI), and pulmonary complications. Secondary outcome measures included cardiac arrhythmias, venous thromboembolism (VTE), and duration of stay in the intensive care unit and hospital. RESULTS: Four hundred sixty-three patients were identified; 56 patients were excluded for incomplete data, leaving 407 patients in the 2 groups combined. Of these, 259 patients underwent amputation under regional anesthesia; 148 underwent amputation under general anesthesia. Patients in the regional anesthesia group were older (76.6 vs. 71.6 years; P=0.001) and had a lower body mass index (25.2 vs. 26.9 kg/m2; P=0.013). They were also less likely to be on preoperative antiplatelet therapy (aspirin or clopidogrel) or anticoagulation (27% vs. 45%; P<0.001). Regional anesthesia was associated with a lower incidence of overall postoperative pulmonary complications (15% vs. 24%; P=0.02) and postoperative arrhythmia (14% vs. 25%; P=0.001). Duration of stay in the intensive care unit (1.92 vs. 3.85 days; P=0.001) and hospital (19.4 vs 23.1 days; P=0.037) were significantly longer in the group receiving general anesthesia. No significant differences in postoperative MI (12% vs. 9%; P=not significant [NS]), VTE (5% vs. 7%; P=NS) or mortality (10% vs. 13%; P=NS) was seen between groups. Controlling for procedure, above- versus below-knee amputation did not significantly alter these results. CONCLUSIONS: Regional anesthesia for patients undergoing MLEA is associated with a lower incidence of postoperative pulmonary complications and cardiac arrhythmias. It is also associated with lower resource use. As such, regional anesthesia should likely be the favored anesthetic modality for patients undergoing MLEA.

Malignant hyperthermia during laparoscopic adjustable gastric banding.

BACKGROUND: We report a rare case of malignant hyperthermia during laparoscopic adjustable gastric banding. CASE DESCRIPTION: A 32-y-old female with no previous history of adverse reaction to general anesthesia underwent laparoscopic adjustable gastric banding. Intraoperative monitoring revealed a sharp increase in end-tidal carbon dioxide, autonomic instability, and metabolic and respiratory acidosis, along with other metabolic and biochemical derangements. She was diagnosed with malignant hyperthermia. Desflurane, the anesthetic agent was discontinued, and the patient was started on intravenous dantrolene. RESULTS: The surgery was completed, and the patient was brought to the surgical intensive care unit for continued postoperative care. She developed muscle weakness and phlebitis that resolved prior to discharge. CONCLUSION: Prompt diagnosis and treatment of malignant hyperthermia leads to favorable clinical outcome. This clinical entity can occur in the bariatric population with the widely used desflurane. Bariatric surgeons and anesthesiologists alike must be aware of the early clinical signs of this rare, yet potentially fatal, complication.

Lactobacillus fermentum, a pathogen in documented cholecystitis.

INTRODUCTION: Lactobacillus species are probiotics proven to exhibit various preventative as well as therapeutic properties. While lactobacillus species have been implicated in the formation of dental caries, endocarditis and bacteremia, their role as pathogens in cholecystitis has not been reported. We present a rare case of Lactobacillus fermentum working as a pathogen in cholecystitis. PRESENTATION OF CASE: An 81-year old male was admitted with right upper quadrant abdominal pain. His signs, symptoms, laboratory values and imaging were consistent with a diagnosis of cholecystitis with ascending cholangitis. In view of his co-morbidity and severe sepsis, the patient was treated non-operatively with antibiotics and cholecystostomy. L. fermentum, which was vancomycin resistant, was identified from the cholecystostomy aspirate and from anaerobic blood culture. The patient went into septic shock, developed multi-organ dysfunction syndrome and eventually died. DISCUSSION: Commensal bacteria such as L. fermentum are known to modulate immunity, reduce the pathogenicity of gastrointestinal organisms and play a therapeutic role in various disease processes. We isolated L. fermentum as a pathogen in a documented case of cholecystitis with ascending cholangitis. CONCLUSION: While the routine use lactobacillus species as a probiotic is supported in the literature, understanding its potential role as a pathogen may allow more judicious use of these bacteria and encourage research to elucidate the pathogenicity of lactobacillus species.