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3307 citation(s) found for "Vu, Alexander".

Internal Fixation of Unstable Osteochondritis Dissecans in the Skeletally Mature Knee with Metal Screws
Barrett, Ian J. , King, Alexander H. , Riester, Scott M. , Wijnen, André J. van , Levy, Bruce A. , Krych, Aaron J. , Barrett, Ian, Riester, Scott, van Wijnen, Andre, Stuart, Michael J. , van Wijnen, Andre J , Krych, Aaron J

CARTILAGE | December 30, 2015 | Volume: 7 | Issue: 2 | Pages: 157-162

10.1177/1947603515622662 | PMID 27047638 Get It

Purpose Several bioabsorbable and metal options are available for internal fixation of an unstable osteochondritis dissecans (OCD) lesion, but currently there are little data on outcomes with metal headless compression screws in the adult knee. The purpose of this study was to determine (1) the radiographic healing rates, (2) midterm clinical outcomes, and (3) comparison between healed and unhealed OCD fragments after use of headless metal compression screws for the treatment of unstable OCD lesions in the knees of skeletally mature patients. Methods Retrospective chart review for all skeletally mature patients who presented with unstable femoral condyle OCD lesions of the knee was conducted. All patients underwent open or arthroscopic reduction and internal fixation using headless metal compression screws. Preoperative and postoperative radiographs were reviewed with healing defined as radiographic evidence of union of the OCD progeny fragment with the condyle. Clinical outcome data were collected retrospectively using 3 validated outcome scores: International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Outcome Score (KOOS), and Marx. Results Twenty-two knees in 22 patients with a mean age of 21 years (range= 14-37 years) were followed for an average of 8.7 years (range = 2-22 years). Metal, headless, cannulated compression screws were used in all 22 cases. At a mean of 31 months postoperatively (range = 2-262), fragment union was observed in 18 knees (82%). The remaining 4 knees (18%) required loose fragment excision and hardware removal at a mean of 9 months (range = 2-16 months) postoperatively. Mean postoperative Marx score was 7 (range = 0-16), the mean postoperative IKDC score was 85 (range = 62-100), and mean KOOS scores included KOOS Pain (93; range = 69-100), KOOS Symptoms (86; range = 71-100), KOOS ADL (98; range = 90-100), KOOS Sports (82; range = 50-100), and KOOS QOL (76; range = 50-100). Conclusion Headless metal compression screws provide a satisfactory union rate for treatment of unstable OCD lesions of the femoral condyles in skeletally mature patients. Patients achieving union have good knee function, maintain satisfactory activity levels, and have superior knee outcomes compared with those that failed to heal after fixation at mid to long-term follow-up.
Open Anatomic Reconstruction of the Medial Collateral Ligament and Posteromedial Corner
Prince, Matthew, Blackman, Andrew J. , King, Alexander H. , Levy, Bruce A. , Prince, Matthew R, Stuart, Michael J.

Arthroscopy Techniques | December 28, 2015 | Volume: 4 | Issue: 6 | Pages: No page available

10.1016/j.eats.2015.08.013 | PMID 27284529 Get It

Abstract Injuries to the medial collateral ligament (MCL) and posteromedial corner can occur in isolation or in the setting of multiligamentous knee injuries. Reconstruction of the MCL and posteromedial corner is indicated in the setting of a multiligamentous knee injury. Isolated cases failing nonoperative treatment may also undergo surgical treatment. Our preferred technique for anatomic medial‐sided knee reconstruction is an open anatomic MCL reconstruction using an Achilles tendon allograft along with direct repair of all associated medial and posteromedial structures. Technique Video video See video under supplementary data.
Survival and outcomes of patients with unoperated single ventricle
Poterucha, Joseph T., Anavekar, Nandan S., Egbe, Alexander C. , Julsrud, Paul R., Connolly, Heidi M. , Ammash, Naser M., Warnes, Carole A.

Heart | December 23, 2015 | Volume: 102 | Issue: 3 | Pages: 216-222

10.1136/heartjnl-2015-308440 | PMID 26701967 Get It

Objective Patients with unoperated single ventricle (SV) rarely survive into adulthood with good functional status and may develop Eisenmenger's syndrome (ES). We report outcomes of a 30-year cohort of such patients. Methods Adult patients with unoperated SV were identified by searching the Mayo Clinic medical record from 1984 to 2014. Clinical data were collected and compared between patients with pulmonary stenosis (PS) and ES. Results 24 patients were identified (median peak-age 56 (31–77) years (11 ES, 13 PS); 22 had left ventricular morphology. 50-year transplant-free survival was 65% (95% CI 43 to 81). Median age at death was 55 years (31–77 years); 15 deaths (62%) occurred before oral pulmonary vasodilators were commercially available. Two-thirds of the cohort demonstrated preserved New York Heart Association functional class and median EF was 60% (49% to 62%). The majority of patients to survive into the fifth decade exhibited anatomy of double-inlet LV (DILV) with PS. Conclusion Selected patients with unoperated SV with PS and ES can survive with good functional class up to the eighth decade with good medical management. DILV/PS appears to be the ideal phenotype for advanced survival. Our outcomes may be considered when such patients with SV having ‘balanced’ physiology are evaluated for Fontan palliation. However, additional prospective study will be necessary to verify this assertion.
P1‐223: Characterizing cognitive processes affected by Alzheimer's disease using markov models
Alexander, Gregory E. , Batchelder, William H. , Shankle, William R. , Petersen, Ronald C.

Alzheimer's & Dementia | December 15, 2015 | Volume: 11 | Issue: 7S_Part_9 | Pages: No page available

10.1016/j.jalz.2015.06.423 Get It

Treatment Planning Studies in Patient Data With Scanned Carbon Ion Beams for Catheter‐Free Ablation of Atrial Fibrillation
Constantinescu, A., Packer, Douglas L. , Bert, Christoph , Durante, Marco , Graeff, Christian , Lehmann, H. Immo , Bert, Christoph , Durante, Marco , Graeff, Christian

Journal of Cardiovascular Electrophysiology | December 8, 2015 | Volume: 27 | Issue: 3 | Pages: 335-344

10.1111/jce.12888 | PMID 26638826 Get It

Noninvasive AF Ablation With Carbon IonsIntroductionCatheter ablation with isolation of the pulmonary veins is a common treatment option for atrial fibrillation but still has insufficient success rates and carries several interventional risks. These treatment planning studies assessed if high‐dose single fraction treatment with scanned carbon ions (12C) can be reliably delivered for AF ablation, while sparing risk structures and considering respiratory and contractile target motion.Methods and ResultsTime resolved CT scans of complete respiratory and cardiac cycles of 9 and 5 patients, respectively, were obtained. Ablation lesions and organs at risk for beam delivery were contoured. Single fraction intensity‐modulated particle therapy with target doses of 25 and 40 Gy were studied and motion influences on these deliveries mitigated. Respiration had a large influence on lesion displacement (≤ 2 cm). End expiration could be exploited as a stable gating window. Smaller, but less predictable, heartbeat displacements (< 6 mm) remained to be mitigated because cardiac contraction resulted in insufficient dose coverage (V95 < 90 %) if uncompensated. Repeated irradiation (12C beam rescanning) during breath hold was used to accommodate contractile motion, resulting in good dose coverage. Dose depositions to all organs at risk were carefully examined and did not exceed values for X‐ray cancer treatment.ConclusionTreatment planning of 12C with delivery of physical ionizing radiation doses that have been described to induce complete block is feasible for AF ablation, considering human anatomy, dose constraints, and encasing underlying motion patterns from respiration and cardiac contraction at the LA–PV junction into treatment planning.
Blood Pressure Control and Risk of Stroke or Systemic Embolism in Patients With Atrial Fibrillation: Results From the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) Trial
Rao, Meena P., Halvorsen, Sigrun , Wojdyla, Daniel , Thomas, Laine , Alexander, John H. , Hanna, Michael , Caterina, Raffaele De , Erol, Çetin , Goto, Shinya , Laņas, Fernando , Lewis, Basil S. , Wallentin, Lars , Granger, Christopher B. , Hanna, Michael G. , Hylek, Elaine M. , Bahit, Maria Cecilia , Lópes, Renato D. , Husted, Steen , Gersh, Bernard J. , Granger, Christopher B , Lanas, Fernando

Journal of the American Heart Association | December 1, 2015 | Volume: 4 | Issue: 12 | Pages: No page available

10.1161/jaha.115.002015 | PMID 26627878 Get It

Background Patients with atrial fibrillation ( AF ) and hypertension are at high risk for stroke. Previous studies have shown elevated risk of stroke in patients with AF who have a history of hypertension (regardless of blood pressure [ BP ] control) and in patients with elevated BP . We assessed the association of hypertension and BP control on clinical outcomes. Methods and Results In ARISTOTLE (n=18 201), BP was evaluated as history of hypertension requiring treatment and elevated BP (systolic ≥140 and/or diastolic ≥90 mm Hg) at study entry and any point during the trial. Hazard ratios ( HR s) were derived from Cox proportional hazards models including BP as a time‐dependent covariate. A total of 15 916 (87.5%) patients had a history of hypertension requiring treatment. In patients with elevated BP measurement at any point during the trial, the rate of stroke or systemic embolism was significantly higher ( HR , 1.53; 95% confidence interval [ CI ], 1.25–1.86), as was hemorrhagic stroke ( HR 1.85; 95% CI , 1.26–2.72) and ischemic stroke ( HR , 1.50; 95% CI , 1.18–1.90). Rates of major bleeding were lower in patients with a history of hypertension ( HR , 0.80; 95% CI , 0.66–0.98) and nonsignificantly lower in patients with elevated BP at study entry ( HR , 0.89; 95% CI , 0.77–1.03). The benefit of apixaban versus warfarin on preventing stroke or systemic embolism was consistent among patients with and without a history of hypertension ( P interaction=0.27), BP control at baseline ( P interaction=0.43), and BP control during the trial ( P interaction=0.97). Conclusions High BP measurement at any point during the trial was independently associated with a substantially higher risk of stroke or systemic embolism. These results strongly support efforts to treat elevated BP as an important strategy to optimally lower risk of stroke in patients with AF . Clinical Trial Registration URL : https://ClinicalTrials.gov/ . Unique identifier: NCT 00412984.
Complementary and Integrative Medicine at Mayo Clinic
Pang, Ran , Wang, Shihan , Tian, Lin , Lee, Mark C. , Do, Alexander , Cutshall, Susanne M. , Li, Guangxi , Bauer, Brent A. , Thomley, Barbara S. , Chon, Tony Y. , Li, Guangxi

The American Journal of Chinese Medicine | December 1, 2015 | Volume: 43 | Issue: 08 | Pages: 1503-1513

10.1142/s0192415x15500858 | PMID 26621439 Get It

Complementary and alternative medicine (CAM) has gained acceptance throughout the industrialized world. The present study was performed to provide information about the use of CAM at Mayo Clinic, an academic medical center in Northern Midwest of the US. We retrospectively reviewed the electronic medical records of 2680 patients visiting the CAM program at Mayo Clinic, Rochester, between 1 July 2006 and 31 March 2011. Services provided included acupuncture, massage, integrative medical consultations and executive stress management training. Data including age, gender, race, diagnosis and the number of treatment/consultation sessions were collected to describe the use of CAM in our institute over the last several years. It was found that the mean (standard deviation) age of patient was 52.6 (15.5) years. Of those, 73.1% were female and 26.9% were male. Most patients were white. The number of patients referred to CAM increased significantly from 2007 to 2010. The three most common diagnostic categories were back pain (12.9%), psychological disorders (11.8%), and joint pain (9.6%). Back pain was the most common diagnosis for patients receiving acupuncture, and fibromyalgia was the most common for patients receiving massage therapy. Psychological disorders (i.e., stress) were the major diagnosis referred to both integrative medical consults and executive stress management training. These results suggest that the diseases related to pain and psychological disorders are the main fields of CAM use. It also shows the increasing trend of the use of CAM at an academic medical center in the US.
Is Subchondral Acetabular Edema or Cystic Change on MRI a Contraindication for Hip Arthroscopy in Patients With Femoroacetabular Impingement?
Krych, Aaron J. , King, Alexander H. , Berardelli, Rebecca L., Sousa, Paul L., Levy, Bruce A. , Krych, Aaron J

The American Journal of Sports Medicine | November 30, 2015 | Volume: 44 | Issue: 2 | Pages: 454-459

10.1177/0363546515612448 | PMID 26620297 Get It

Background: The outcome for arthroscopic treatment of femoroacetabular impingement (FAI) can worsen with increasing arthritis. However, there remains a subset of hips with relatively maintained joint space but with acetabular subchondral edema and cystic change with unknown outcome on magnetic resonance imaging (MRI). Purpose: (1) To correlate MRI findings of subchondral acetabular edema/cystic change with arthroscopy grading of articular cartilage and (2) to determine whether postoperative outcome was worse for patients with subchondral edema/cystic change compared with a matched control group. Study Design: Cohort study; Level of evidence, 3. Methods: The records of all patients who underwent arthroscopic hip surgery for FAI at a single institution between 2007 and 2013 were reviewed for subchondral edema/cyst on preoperative MRI. Lesions were characterized by grade using an established classification system and were correlated with arthroscopic articular cartilage changes. A matched cohort of patients without evidence of subchondral edema or cyst was identified. Minimum 2-year outcomes were compared using prospectively collected Hip Outcome Score (HOS) activities of daily living and sport subscales as well as the modified Harris Hip Score (mHHS). Results: Overall, 104 patients were included. Thirty-six patients (18 men, 18 women) with a mean age of 41 years (range, 19-67 years) had subchondral edema, with or without the presence of cystic acetabular changes, at minimum 2-year follow-up (range, 24-60 months). Two patients who underwent total hip replacement were excluded in the outcome score comparison. Thirty-one of 34 patients (91%) had a grade 4 full-thickness cartilage lesion at the time of diagnostic arthroscopy. The mean mHHS was inferior for all patients with subchondral edema/cystic change (79.9 ± 18.7 vs 86.6 ± 12.5; P = .03), and the HOS was also lower (69.1 ± 27.0 vs 79.5 ± 21.4; P = .02). The overall success rate was 67% for all patients with subchondral edema/cystic change compared with 85% in the control group ( P = .04). Conclusion: The presence of a subchondral edema with an acetabular cyst on MRI is indicative of a full-thickness cartilage lesion at the time of arthroscopy. These patients have inferior outcomes for arthroscopic treatment of FAI compared with patients with similar age and activity level without MRI subchondral cystic changes.
Pre‐clinical heterotopic intrathoracic heart xenotransplantation: a possibly useful clinical technique
Abicht, Jan‐Michael , Mayr, Tanja, Reichart, Bruno , Buchholz, Stefan, Werner, Fabian, Lutzmann, Isabelle, Schmoeckel, Michael , Thormann, Michael , Langenmayer, Martin C. , Herbach, Nadja , Pohla, Heike , Herzog, Rudolf, McGregor, Christopher G.A. , Ayares, David , Wolf, Eckhard , Klymiuk, Nikolai , Baehr, Andrea , Kind, Alexander, Hagl, Christian, Ganswindt, Ute , Belka, Claus , Guethoff, Sonja , Brenner, Paolo , Bauer, Andreas , Herzog, Rudolf

Xenotransplantation | November 25, 2015 | Volume: 22 | Issue: 6 | Pages: 427-442

10.1111/xen.12213 | PMID 26602740 Get It

AbstractBackgroundAs a step towards clinical cardiac xenotransplantation, our experimental heterotopic intrathoracic xenotransplantation model offers a beating and ejecting donor heart while retaining the recipient′s native organ as a backup in case of graft failure. Clinically applicable immunosuppressive regimens (IS) were investigated first, then treatments known to be effective in hypersensitized patients or those with recalcitrant rejection reactions.MethodsConsecutive experiments were carried out between 2009 and 2013. Twenty‐one genetically modified pigs (GGTA1‐knockout/hCD46/± thrombomodulin, in one caseHLA‐E instead) were used as donors. In all experiments, two cycles of immunoabsorption reduced preformed antibodies. Recipient baboons were divided into two groups according toISregimen:In group one (n = 10), pre‐treatment started either one (anti‐CD20) or four weeks (anti‐CD20 plus the proteasome inhibitor bortezomib) prior to transplantation. The extended conventional (as for allotransplantation) immunosuppressive maintenance regimen included anti‐thymocyte globuline, tacrolimus, mycophenolate mofetil, methylprednisolone and weekly anti‐CD20.In group two (n = 11), myeloablative pre‐treatment as in multiple myeloma patients (long and short regimens) was added to extended conventionalIS; postoperative total thoracic and abdominal lymphoid irradiation (TLI; single dose of 600cGY) was used to further reduce antibody‐producing cells.ResultsIn the perioperative course, the surgical technique was safely applied: 19 baboons were weaned off extracorporeal circulation and 17 extubated. Nine animals were lost in the early postoperative course due to causes unrelated to surgical technique orISregimen.Excluding these early failures, median graft survival times of group 1 and 2 were 18.5 (12–50) days and 16 (7–35) days. Necropsy examination of group 1 donor organs revealed hypertrophy of the left ventricular wall in the six longer‐lasting grafts; myocardial histology confirmed pre‐clinical suspicion of humoral rejection, which was not inhibited by the extended conventional IS including intensified treatments, and signs of thrombotic microangiopathy.Grafts of group 2 presented with only mild‐to‐moderate features of humoral rejection and thrombotic microangiopathy, except in one case of delayed rejection on day 17. The other experiments in this group were terminated because of untreatable pulmonary oedema, recurring ventricular fibrillation, Aspergillus sepsis, as well as a combination of a large donor organ and late toxic side effects due toTLI.ConclusionsLonger‐term results were difficult to achieve in this model due to theISregimens used. However, we conclude that heterotopic intrathoracic heart transplantation may be an option for clinical xenotransplantation.
Subcutaneous infusion of kisspeptin‐54 stimulates gonadotrophin release in women and the response correlates with basal oestradiol levels
Narayanaswamy, Shakunthala, Jayasena, Channa , Ng, Noel , Ratnasabapathy, Risheka , Prague, Julia , Papadopoulou, Deborah , Abbara, Ali , Comninos, Alexander , Bassett, Paul , Bloom, Stephen R. , Veldhuis, Johannes D. , Dhillo, Waljit S. , Jayasena, Channa N

Clinical Endocrinology | November 17, 2015 | Volume: 84 | Issue: 6 | Pages: 939-945

10.1111/cen.12977 | PMID 26572695 Get It

SummaryBackground and objectiveKisspeptin stimulates hypothalamic GnRH secretion resulting in gonadotrophin release and has potential as a future therapeutic. Chronic subcutaneous infusion of kisspeptin via a pump (similar to an insulin pump) may provide an alternative route of administration in the future. We investigated for the first time in humans, the gonadotrophin response to subcutaneous (SC) infusions of kisspeptin‐54 in healthy women. Women are markedly more responsive to exogenous kisspeptin in the late follicular phase preovulation when oestradiol levels are naturally high. Therefore, we further investigated whether there was a correlation between baseline oestradiol levels and LH response to kisspeptin.Design and patientsA prospective, single‐blinded placebo‐controlled study. Healthy women (n = 4) received an 8‐h SC infusion of kisspeptin‐54 0·1, 0·3 or 1·0 nmol/kg/h or saline in the early follicular phase of 4 separate menstrual cycles. Gonadotrophins and oestradiol were measured every 10 min during the infusions.ResultsSC infusion of kisspeptin‐54 increased LH and FSH. The LH response to SC infusion of kisspeptin‐54 (0·3 and 1·0 nmol/kg/h) positively correlated with baseline oestradiol levels (P < 0·001). Further statistical analyses showed that in the 1·0 nmol/kg/h group, a 100pmol/l rise in baseline oestradiol was associated with a 1·0 IU/l increase in LH.ConclusionsKisspeptin administered via a SC infusion could be a viable future therapeutic route of administration for patients with infertility. Baseline oestradiol levels may be an important determinant of the gonadotrophin response to kisspeptin treatment in women and should be taken into consideration when evaluating gonadotrophin response.