Animal Models for Tendon Repair Experiments: A Comparison of Pig, Sheep and Human Deep Flexor Tendons in Zone II.

BACKGROUND: This laboratory study compared pig, sheep and human deep flexor tendons in regards to their biomechanical comparability. METHODS: To investigate the relevant biomechanical properties for tendon repair experiments, the tendons resistance to cheese-wiring (suture drag/splitting) was assessed. Cheese-wiring of a suture through a tendon is an essential factor for repair gapping and failure in a tendon repair. RESULTS: Biomechanical testing showed that forces required to pulling a uniform suture loop through sheep or pig tendons in Zone II were higher than in human tendons. At time point zero of testing these differences did not reach statistical significance, but differences became more pronounced when forces were measured beyond initial cheese-wiring (2 mm, 5 mm and 10 mm). The stronger resistance to cheese-wiring was more pronounced in the pig tendons. Also regarding size and histology, sheep tendons were more comparable to human tendons than pig tendons. CONCLUSIONS: Differences in tendon bio-properties should be kept in mind when comparing and interpreting the results of laboratory tendon experiments.

History and Nomenclature of Multistrand Repairs in Digital Flexor Tendons.

Multistrand core suture repairs have become the mainstay of digital flexor tendon repair in recent decades. Here we briefly describe the history of the development of these multistrand repair methods and their correct nomenclature. A historical account, their evolution, the correct use of nomenclature, and some technical points are reviewed.

Current practice of primary flexor tendon repair: a global view.

In this article, a group of international leaders in tendon surgery of the hand provide details of their current methods of primary flexor tendon repair. They are from recognized hand centers around the world, from which major contributions to the development of methods for flexor tendon repair have come over the past 2 decades. Changes made since the early 1990s regarding surgical methods and postoperative care for the flexor tendon repair are also discussed. Current practice methods used in the leading hand centers are summarized, and key points in providing the best possible clinical outcomes are outlined.

Characterization and outcome of patients with severe symptomatic aortic stenosis referred for percutaneous aortic valve replacement.

OBJECTIVE: Many high-risk patients with severe symptomatic aortic stenosis are not referred for surgical aortic valve replacement. Although this patient population remains ill-defined, many of these patients are now being referred for percutaneous aortic valve replacement. We sought to define the characteristics and outcomes of patients referred for percutaneous aortic valve replacement. METHODS: Between February 2006 and March 2007, 92 patients were screened for percutaneous aortic valve replacement. Clinical and echocardiographic characteristics of patients undergoing surgical aortic valve replacement, percutaneous aortic valve replacement, balloon aortic valvuloplasty, or no intervention were compared. The primary end point was all-cause mortality. RESULTS: Nineteen patients underwent successful surgical aortic valve replacement, 18 patients underwent percutaneous aortic valve replacement, and 36 patients had no intervention. Thirty patients underwent balloon aortic valvuloplasty, and of these, 8 patients were bridged to percutaneous aortic valve replacement and 3 were bridged to surgical aortic valve replacement. Of the remaining 19 patients undergoing balloon aortic valvuloplasty, bridging to percutaneous aortic valve replacement could not be accomplished because of death (n = 9 [47%)], exclusion from the percutaneous aortic valve replacement protocol (n = 6 [32%]), and some patients improved after balloon aortic valvuloplasty and declined percutaneous aortic valve replacement (n = 4 [21%]). The most common reasons for no intervention included death while awaiting definitive treatment (n = 10 [28%]), patient uninterested in percutaneous aortic valve replacement (n = 10 [28%]), and questionable severity of symptoms or aortic stenosis (n = 9 [25%]). Patients not undergoing aortic valve replacement had higher mortality compared with those undergoing aortic valve replacement (44% vs 14%) over a mean duration of 220 days. CONCLUSION: Symptomatic patients with severe aortic stenosis have high mortality if timely aortic valve replacement is not feasible. Twenty percent of the patients referred for percutaneous aortic valve replacement underwent surgical aortic valve replacement with good outcome. Patients undergoing balloon aortic valvuloplasty alone or no intervention had unfavorable outcomes.

An 11-year, single-institution analysis of intra-aortic balloon pump use in cardiac surgery.

OBJECTIVES: The primary objective of this study was to analyze perioperative intra-aortic balloon pump (IABP) insertion in patients undergoing cardiac surgery in the authors' institution from 1995 to 2005 and to propose an explanation for changes in use over this period. A secondary objective was to assess patient variables associated with IABP use. DESIGN: This is a retrospective study including patients who underwent cardiac surgery between 1995 and 2005. SETTING: The Cardiothoracic Anesthesia Patient Registry of a single teaching institution was queried to obtain the required information. PARTICIPANTS: Thirty thousand two hundred sixty-nine cardiac surgery patients. INTERVENTIONS: Intra-aortic balloon pump insertion before surgery, after cardiopulmonary bypass, or in the cardiovascular intensive care unit was assessed in patients who underwent isolated coronary artery bypass graft surgery, valve surgery, or both. Select patient variables were analyzed for their association with IABP insertion. Transesophageal echocardiography (TEE) examinations, milrinone use, and mortality rates also were determined. MEASUREMENTS AND MAIN RESULTS: Among 30,269 cardiac surgery patients, 1,310 (4.32%) underwent IABP insertion. Combined preoperative, intraoperative, and postoperative IABP use decreased from 7.8% in 1995 to 3.0% in 2005. Simultaneously, the intraoperative use of milrinone increased from 4.8% to 8.8% and postoperative use increased from 5.2% to 7.8%. The number of intraoperative TEE examinations more than doubled from approximately 1,700 to 3,500. The overall mortality for patients with preoperative, intraoperative, and postoperative IABP insertion was 12.6%, 17.5%, and 47.7%, respectively. CONCLUSIONS: From 1995 to 2005, preoperative, intraoperative, and postoperative IABP use decreased by approximately 60% in cardiac surgery patients. Simultaneously, the use of TEE and milrinone each doubled. Although a cause-effect relationship cannot be established from the present study's observational data, the trends coincide and may be related.

Endoscopic robotically-assisted mitral valve repair.

Robotic surgical instrumentation allows minimally invasive mitral valve repair through an endoscopic approach, eliminating the need for a thoracotomy. Robotic instruments are inserted through port-like incisions in the right hemithorax, while cardiopulmonary bypass is established via cannulation of the femoral vessels. We describe triangular resection, a simple and reproducible robotically-assisted technique for repair of posterior leaflet prolapse. The repair is completed with insertion of an annuloplasty ring.

Toward predictable repair of regurgitant aortic valves: a systematic morphology-directed approach to bicommissural repair.

OBJECTIVES: Our purpose was to investigate a new approach to bicommissural repair of regurgitant aortic valves. BACKGROUND: Repair of regurgitant aortic valves is not widely accepted, but interest is increasing, particularly for bicuspid valves. We hypothesize that a systematic, segmental approach to morphology and corresponding morphology-directed repair will improve decision making and success. METHODS: From December 2001 to July 2007, a systematic surgical approach to valve analysis and bicommissural repair was applied prospectively to 63 consecutive patients with pure aortic valve regurgitation, mean age 40 +/- 12 years. Cusp, commissure, and root morphologies were analyzed sequentially by direct inspection. Each abnormality was corrected by corresponding morphology-directed repair procedures. Retrospectively, 2 echocardiographic indexes--of tissue pliability (change in systolic to diastolic area) and coaptation deficiency (conjoint and reference cusp heights vs. "annulus" diameter)--were developed to evaluate repairability. RESULTS: Forty-two (67%) valves were repaired and 21 (33%) replaced. Regurgitation was related primarily to cusp (prolapse, restriction) and commissure (splaying) morphology; root pathology was less important. Morphology-directed repair included cusp maneuvers in all, commissural maneuvers in 71%, and root procedures in 33%. Restriction and cusp tissue deficiency limited repairability. Echocardiography reflected this in greater tissue pliability of successfully repaired valves compared with replaced ones (conjoint cusp 61 +/- 16% vs. 34 +/- 17%; reference cusp 65 +/- 16% vs. 42 +/- 16%; p = 0.0001) and less coaptation deficiency (1.06 +/- 0.24 for repaired and 1.27 +/- 0.19 for replaced valves; p = 0.002). CONCLUSIONS: Systematic segmental analysis of morphology and a logical morphology-directed surgical approach facilitate aortic valve repair. Initial application of this paradigm suggests sufficient mobile cusp tissue is a key determinant of repairability.

Project among African-Americans to explore risks for schizophrenia (PAARTNERS): recruitment and assessment methods.

The Project among African-Americans to Explore Risks for Schizophrenia (PAARTNERS) is a multi-site, NIMH-funded study that seeks to identify genetic polymorphisms that confer susceptibility to schizophrenia among African-Americans by linkage mapping and targeted association analyses. Because deficits in certain dimensions of cognitive ability are thought to underlie liability to schizophrenia, the project also examines cognitive abilities in individuals affected by schizophrenia and their extended family members. This article describes PAARTNERS study design, ascertainment methods and preliminary sample characteristics. We aim to recruit a sample of 1260 African-American families, all of whom have at least one proband with schizophrenia or schizoaffective disorder. The data collection protocol includes a structured Diagnostic Interview for Genetic Studies, Family Interview for Genetic Studies, focused neurocognitive assessment, medical records review, and the collection of blood or buccal cells for genetic analyses. We have currently completed study procedures for 106 affected sib-pair, 457 case-parent trio and 23 multiplex families. A total of 289 probands have completed the best estimate final diagnosis process and 1153 probands and family members have been administered the computerized neuropsychological battery. This project lays the foundation for future analysis of cognitive and behavioral endophenotypes. This novel integration of diagnostic, neurocognitive and genetic data will also generate valuable information for future phenotypic and genetic studies of schizophrenia.

Phoneme manipulation not onset-rime manipulation ability is a unique predictor of early reading.

BACKGROUND: Phonological awareness is known to be an excellent predictor of later reading acquisition. It remains unclear, however, whether phoneme manipulation alone best explains this association or whether an additional direct contribution of onset-rime awareness is predictive. This issue is explored here. METHOD: A longitudinal study is reported predicting national test and teacher-assessed performance of 351 children aged 7 from phonological awareness measures, pupil baseline attainment and background measures at age 5. RESULTS: Explicit phoneme manipulation skills at age 5 correlated most strongly with literacy skills at age 5. Phoneme manipulation at age 5 predicted all four reading measures taken at age 7 after pupil background, baseline data and onset-rime awareness were controlled in regression analyses. Onset-rime manipulation did not predict reading at 7 in parallel analyses. After controlling for initial reading at age 5, phoneme manipulation still predicted reading comprehension, and teacher-assessed reading and writing at age 7. CONCLUSIONS: Results support the existence of a route from phoneme manipulation, but not an additional direct route from explicit onset-rime manipulation at 5, to reading at 7. Practically, findings show that professionals can augment baseline and pupil background data with phoneme manipulation screening in the early identification of learning needs.

Right ventricular exclusion surgery for arrhythmogenic right ventricular dysplasia with cardiomyopathy.

IMPLICATIONS: The authors describe the management of a patient with arrhythmogenic right ventricular dysplasia treated with right ventricular exclusion surgery.

Expression of hunchback protein in a subset of ectodermal teloblasts of the oligochaete annelid Tubifex.

The early expression patterns of hunchback protein (T-hb protein) were examined in the oligochaete Tubifex, using an antibody raised to the LZF2 protein in leech. This antibody recognizes a 60-kDa polypeptide in the Tubifex embryo. Before teloblastogenesis, T-hb protein is expressed in every cleavage-stage blastomere. At the completion of teloblastogenesis, the only cells expressing T-hb are a fraction of the micromere-derived epithelial cells. During gastrulation, nuclear T-hb is seen in spreading micromere-derived epithelial cells and also in a subset of ectodermal teloblasts. Comparisons of these results with those from other annelids suggest that hb expression in the early cleavage blastomeres and the micromere-derived epithelium are features highly conserved among annelids. In contrast, hb expression in teloblasts appears to be an innovation evolved in the oligochaetes.

Assistência circulatória com aparelho Heart Mate na Cleveland Clinic Foundation: experiência inicial e futuras aplicaçöes / Circulatory assistance with Heart Mate appliance at the Cleveland Clinic Foundation: clinical experience and future uses

Estudar a experiência inicial em assistência circulatória ventricular esquerda com o aparelho pneumático implantável Heart Mate( 1000 IP, analisando suas características e aplicaçöes clínicas. Material e Métodos: Entre dez/91 e Set/94 (45 meses) 33 pacientes em choque cardiogênico por miocardiopatia isquêmica ou dilatada foram assistidos, com esse aparelho, por um tempo de 0 a 153 dias (média de 76 dias, nos pacientes que chegaram a ser transplantados). O diagnóstico, o tempo de assistência circulatória, os parâmetros hemodinâmicos (índice cardíaco, gradiente transpulmonar, fraçäo de ejeçäo do ventrículo direito, resistência vascular pulmonar e variaçäo da área do ventrículo direito), assim como as complicaçöes clínicas säo apresentados e discutidos. Valores pré e pós implante säo apresentados como média +/- desvio padräo e comparados por teste T pareado. Resultados: A melhora hemodinâmica foi estatisticamente significante (p<0,05). Houve 9 (27,3 por cento) óbitos, pelas seguintes complicaçöes: sepse, falência de VD e insuficiência respiratória. Vinte e quatro pacientes foram transplantados. Näo houve nenhum caso de tromboembolismo. Conclusöes: Houve melhora clínica em pacientes com elevado risco para transplante cardíaco de urgência, com relativamente baixa taxa de morbi-mortalidade durante a assitência e alta taxa de transplantes (69,7 por cento). Os resultados encorajam o uso desse aparelho para tratamento da fase final da insuficiência cardíaca congestiva grave.