Distal tibia allograft for glenohumeral instability: does radius of curvature match?

BACKGROUND: A distal tibia osteochondral allograft is a potential graft option for glenoid reconstruction because the distal tibia may have a similar radius of curvature (ROC) as the glenoid. This study evaluated ROC mismatch as measured on computed tomography (CT) scans between the glenoid, distal tibia, and humeral head. METHODS: Bilateral CT images were formatted for 10 decedents from the Office of the Medical Investigator database, giving 20 specimens per anatomic location. The ROCs of the glenoid, distal tibia, and humeral head were measured. A statistical model was generated to assess ROC mismatch of randomly paired distal tibias and glenoids. RESULTS: The mean ± standard deviation ROC was 2.9 ± 0.25 cm for the glenoid, 2.3 ± 0.21 cm for the distal tibia, and 2.5 ± 0.12 cm for the humeral head. No differences were found in laterality, intraobserver, or interobserver measurements. The least-squares difference in the ROC between the glenoid and tibia was 0.57 cm, glenoid and humerus was 0.40 cm, and humerus and tibia was 0.17 cm. Only 22% of randomly paired distal tibias and glenoids had a difference in ROC of 0.3 cm or less. CONCLUSION: CT measurement of the ROC of the glenoid, distal tibia, and humeral head is reliable and reproducible. The probability of obtaining a random distal tibia allograft with a similar ROC to the glenoid is low. Obtaining ROC measurements of the injured glenoid and the distal tibia allograft specimen before use for glenoid reconstruction may be useful.

Comparative evaluation of left ventricular mass regression after aortic valve replacement: a prospective randomized analysis.

BACKGROUND: We assessed the hemodynamic performance of various prostheses and the clinical outcomes after aortic valve replacement, in different age groups. METHODS: One-hundred-and-twenty patients with isolated aortic valve stenosis were included in this prospective randomized randomised trial and allocated in three age-groups to receive either pulmonary autograft (PA, n = 20) or mechanical prosthesis (MP, Edwards Mira n = 20) in group 1 (age < 55 years), either stentless bioprosthesis (CE Prima Plus n = 20) or MP (Edwards Mira n = 20) in group 2 (age 55-75 years) and either stentless (CE Prima Plus n = 20) or stented bioprosthesis (CE Perimount n = 20) in group 3 (age > 75). Clinical outcomes and hemodynamic performance were evaluated at discharge, six months and one year. RESULTS: In group 1, patients with PA had significantly lower mean gradients than the MP (2.6 vs. 10.9 mmHg, p = 0.0005) with comparable left ventricular mass regression (LVMR). Morbidity included 1 stroke in the PA population and 1 gastrointestinal bleeding in the MP subgroup. In group 2, mean gradients did not differ significantly between both populations (7.0 vs. 8.9 mmHg, p = 0.81). The rate of LVMR and EF were comparable at 12 months; each group with one mortality. Morbidity included 1 stroke and 1 gastrointestinal bleeding in the stentless and 3 bleeding complications in the MP group. In group 3, mean gradients did not differ significantly (7.8 vs 6.5 mmHg, p = 0.06). Postoperative EF and LVMR were comparable. There were 3 deaths in the stented group and no mortality in the stentless group. Morbidity included 1 endocarditis and 1 stroke in the stentless compared to 1 endocarditis, 1 stroke and one pulmonary embolism in the stented group. CONCLUSIONS: Clinical outcomes justify valve replacement with either valve substitute in the respective age groups. The PA hemodynamically outperformed the MPs. Stentless valves however, did not demonstrate significantly superior hemodynamics or outcomes in comparison to stented bioprosthesis or MPs.

In-vivo evaluation of the BioPhysio valve prosthesis in the aortic position.

BACKGROUND AND AIM OF THE STUDY: The new BioPhysio aortic prosthesis is a pericardial valve with a flexible stent that can be implanted with a single suture line. The study aim was to evaluate the in-vivo implantation characteristics, preservation of dynamic motion of the aortic root, and hemodynamic performance of this bioprosthesis. METHODS: The BioPhysio valve was implanted, in the aortic position, in 10 young adult male sheep. Transesophageal and intracardiac echocardiography were carried out postoperatively for hemodynamic evaluation. Cineangiography was performed both preoperatively and postoperatively to assess aortic root dynamics and to document the absence of aortic regurgitation. Cardiac output was monitored via a Swan-Ganz catheter, both preoperatively and postoperatively. RESULTS: The BioPhysio valve was implanted with interrupted mattress sutures in seven cases, and with continuous sutures in three cases. At a mean cardiac output of 5.9 l/min, the mean transaortic pressure gradients were 5.93 and 3.6 mmHg for the 19- and 21-mm valves, respectively, and the mean effective orifice areas were 2.08 and 2.65 cm2. Mean dilation of the aortic root, measured as the maximum expansion of the radiopaque frame in systole, was 9.01%. CONCLUSION: The unique flexible stent design of the new BioPhysio valve preserves the dynamic motion of the aortic root, by combining the hemodynamic benefits of stentless valves with the ease of implantation of stented bioprostheses.

[Endovascular interventions of the descending thoracic aorta]. / Endovaskuläre Interventionen der thorakalen Aorta descendens.

Endovascular interventions of the descending thoracic aorta have been established as an alternative to conventional open surgery. Initially, they were limited to elective patients with a high risk profile for open surgery, but soon their use was extended to emergencies as well. In the elective setting, endovascular interventions significantly lowered short-term morbidity and mortality. These excellent perioperative results were reproducible in the emergency setting, thereby leading to superior outcomes for patients treated by endovascular stent grafts when compared to the conventional open surgical approach. However, some questions regarding long-term durability of these devices remain unanswered. Stent-graft failures at mid and long-term follow-up have been reported in the literature. The progressive nature of stent graft-related mid- and long-term complications stresses the need for continued surveillance of these patients.

Do pulmonary autografts provide better outcomes than mechanical valves? A prospective randomized trial.

BACKGROUND: The objective of this study was to compare the performance of pulmonary autografts with mechanical aortic valves, in the treatment of aortic valve stenosis. METHODS: Forty patients with aortic valve stenoses, and below the age of 55 years, were randomly assigned to receive either pulmonary autografts (n = 20) or mechanical valve (Edwards MIRA; Edwards Lifesciences, Irvine, CA) prostheses (n = 20). Clinical outcomes, left ventricular mass regression, effective orifice area, ejection fraction, and mean gradients were evaluated at discharge, 6 months, and one year after surgery. Follow-up was complete for all patients. RESULTS: Hemodynamic performance was significantly better in the Ross group (mean gradient 2.6 mm Hg vs 10.9 mm Hg, p = 0.0005). Overall, a significant decrease in left ventricular mass was found one year postoperatively. However, there was no significant difference in the rate and extent of regression between the groups. There was one stroke in the Ross group and one major bleeding complication in the mechanical valve group. Both patients recovered fully. CONCLUSIONS: In our randomized cohort of young patients with aortic valve stenoses, the Ross procedure was superior to the mechanical prostheses with regard to hemodynamic performance. However, this did not result in an accelerated left ventricular mass regression. Clinical advantages like reduced valve-related complications and lesser myocardial strain will have to be proven in the long term.

Emergency endovascular interventions for acute thoracic aortic rupture: four-year follow-up.

OBJECTIVE: High mortality and paraplegia rates associated with the surgical management of acute thoracic aortic ruptures limit its success. It was our objective to evaluate whether emergency endovascular interventions would improve the outcomes of these patients. METHODS: Sixty patients aged 28 to 83 years were admitted to our institution with an acute rupture of the thoracic aorta (27 ruptured aneurysms, 15 perforated type B dissections, 18 traumatic ruptures). Twenty-eight patients were treated surgically with cardiopulmonary bypass, and 32 patients were acutely treated with an endovascular stent graft. Medical records were reviewed for prehospital and emergency department data, operative findings, and outcomes. Patients were followed up at yearly intervals with high-resolution multidetector computed tomographic angiography. RESULTS: Perioperatively, there were 1 death (3.1%) among the 32 patients in the endovascular group and 5 deaths (17.8%) among the 28 patients in the surgical group. There were 4 late deaths in the endovascular group and 1 in the surgical group. There were 2 access failures in the endovascular group. There were 1 stroke in the endovascular group and 1 case of paraplegia in the surgical group. Three patients in the endovascular group had endovascular leaks develop that required reintervention. Two patients in the endovascular group had late thrombosis of the left subclavian artery. CONCLUSION: Despite encouraging early outcomes, midterm results suggest a trend toward increased reintervention and late complication rates in the endovascular group. Therefore continued surveillance of patients treated with stent grafts is necessary.

Aortic leaflet replacement with the new 3F stentless aortic bioprosthesis.

PURPOSE: Clinical trials with the new 3F stentless aortic bioprosthesis began October 2001, and as one of the first centers to implant this prosthesis in humans, we would like to present our experiences with this new device. DESCRIPTION: The 3F aortic bioprosthesis is a stentless biological heart valve fabricated from three equal leaflets of equine pericardium, assembled in a tubular shape, and implanted in the native aortic root to replace the patient's diseased aortic leaflets. Between January 2002 and August 2002, 24 3F aortic bioprostheses were implanted at our institution. Effective orifice area, mean gradients, and ejection fraction were evaluated by echocardiography at discharge and at 12-month follow-ups after surgery. EVALUATION: At 12-month follow-ups, the 3F bioprosthesis showed a good hemodynamic performance with a significant drop of mean gradients to 10.3 mm Hg, a mean effective orifice area of 1.7 cm2, and a mean ejection fraction of 61.5%. CONCLUSIONS: The clinical performance of the new 3F aortic bioprosthesis is comparable with regular stentless aortic valves. However its unique design facilitates implantation.

Surgical versus endovascular treatment of acute thoracic aortic rupture: a single-center experience.

BACKGROUND: Surgical management of acute thoracic aortic ruptures is controversial, especially in patients with preexisting comorbidities; associated mortality and paraplegia rates remain high. It was our objective to evaluate whether treating these patients acutely with endovascular stent grafts would improve their outcome. METHODS: From November 1999 to February 2002 a total of 54 patients, age 28 to 83 years, were admitted to our institution with an acute rupture of the thoracic aorta (24 ruptured aneurysms, 14 perforated type B dissections, 16 traumatic ruptures). Twenty-eight patients were managed surgically using cardiopulmonary bypass (group 1), and 26 patients were treated acutely with an endovascular stent graft (group 2). The resuscitation protocol and interval from onset of symptoms to treatment was comparable in both groups. Medical records were reviewed for prehospitalization and emergency department data, operative findings, and outcomes. RESULTS: There were 5 of 28 deaths (17.8%) in the surgical group and 1 of 26 deaths (3.8%) in the endovascular group. In the surgical group 1 of 28 patients (3.6%) exhibited paraplegia; there were no cases of paraplegia in the endovascular group. There were 4 of 28 cases (14.3%) of renal failure in group 1 and 1 of 26 (3.8%) in group 2. In group 1, 8 patients (28.6%) required mechanical ventilation for more than 48 hours; there were 2 of 26 patients (7.7%) in group 2 with this ventilatory requirement. Three patients required a repeat thoracotomy for hemorrhage in the surgical group. There were two access failures in the endovascular group. CONCLUSIONS: In the treatment of acute ruptures of the thoracic aorta, the immediate outcome of patients treated with endovascular stent grafts appears to be better than with management by conventional surgical repair.

The clamshell approach for the treatment of extensive thoracic aortic disease.

OBJECTIVE: Management of extensive thoracic aortic disease may present an immense technical challenge. The choice of surgical access and subsequent exposure determines whether a single-stage or a 2-stage approach can be adopted. METHODS: Fifteen patients with extensive thoracic aortic disease underwent resection of the ascending aorta, the aortic arch, and varying segments of the descending aorta. Four patients had concomitant coronary artery bypass grafting and 3 patients had aortic valve reconstruction. All patients were treated with a single-stage approach via a bilateral anterior thoracosternotomy (clamshell incision). RESULTS: There was 1 hospital death (6.6%). Two patients required reoperation for bleeding (13.3%). Two patients needed mechanical ventilation for more than 48 hours. Three patients suffered a stroke (20%). Two patients (13.3%) had transient neurologic dysfunction. None of the patients had renal failure. There were no wound infections in this group. CONCLUSION: The single-stage approach, via a clamshell incision, is a safe and effective procedure for patients who require treatment of extensive thoracic aortic disease and concomitant cardiac lesions.

Emergent endovascular stent grafting for perforated acute type B dissections and ruptured thoracic aortic aneurysms.

BACKGROUND: The purpose of our study was to demonstrate the effectiveness of endovascular stent grafts in the treatment of acutely ruptured thoracic aortic aneurysms and type B dissections as an alternative to the conventional surgical approach in an emergency setting. METHODS: From January 2001 to October 2001, we deployed 11 emergent endovascular stent grafts into the thoracic aorta. We treated seven ruptured aortic aneurysms and four acutely perforated type B dissections. Aortic rupture was confirmed preoperatively by spiral computed tomography. In all cases, hemothorax was present. The average interval from onset of symptoms to treatment was 28.5 hours. We used nine Talent and two Excluder stent grafts. RESULTS: Deployment of the stent grafts was successful in nine cases. There were two cases of access failure due to small caliber of iliac arteries, and 1 of these patients died shortly after the procedure was abandoned, At 12 months of follow-up, there were no cases of paraplegia, stent migration, or endoleaks. There was, however, one temporary renal failure, and 2 patients required mechanical ventilation for more than 48 hours. CONCLUSIONS: Our experiences with emergency endovascular stent grafting show that the procedure is technically feasible, with less morbidity and mortality than conventional open surgery, in high-risk patients.

Vacuum-assisted suction drainage versus conventional treatment in the management of poststernotomy osteomyelitis.

OBJECTIVE: The purpose of our study was to compare vacuum-assisted suction drainage (VASD) to conventional wound management, in the treatment of poststernotomy osteomyelitis (SOM). METHODS: We included a total of 42 patients that developed poststernotomy osteomyelitis and required open wound management, between 1998 and 2000, in this study. Twenty of these patients were treated by VASD and the other 22 by conventional wound management. The patients were well comparable with regards to age, presenting postoperative day, infecting organism and risk factors for osteomyelitis. This was a retrospective study. RESULTS: The patients treated by VASD had a significantly reduced treatment duration (mean 17.2+/-5.8 vs. 22.9+/-10.8 days, P=0.009) and total hospital stay (mean 27.2+/-6.5 vs. 33.0+/-11.0 days, P=0.03). Perioperative mortality was similar, with one early death in each group. CONCLUSION: We conclude from our experience in the treatment of 42 patients with poststernotomy osteomyelitis that VASD shortened wound healing and hospital stay and thus proved to be an excellent alternative to conventional open management of these wounds.

The variable endogenous retroviral insertion in the human complement C4 gene: a transmission study in type I diabetes mellitus.

A variable endogenous retroviral element has been identified in intron 9 of the complement C4 gene [HERV-K(C4)], which maps to the class III region of the major histocompatibility complex (MHC) on chromosome 6p21.3. Genetic susceptibility to type I diabetes is mainly conferred by the MHC locus and the complement C4 region has been implied to contribute to human leukocyte antigen DQ (HLA-DQ) mediated disease risk. As the HERV-K(C4) insertion has been suggested to modulate expression of homologous genes, we investigated its transmission in 220 families with an offspring affected by type I diabetes as a potential disease susceptibility marker. There was no preferential transmission of the HERV-K(C4) insertion to affected offspring (P(TDT) = 0.79). Although 77.7% of HLA-DQ8 carried the HERV-K(C4) insertion, only 52.9% of -DQ2 haplotypes did (P(chi(2)) < 0.01). However, its insertion or deletion did not modulate the risk conferred by HLA-DQ8 (DQA1*0301-DQB1*0302) (P(chi(2)) = 0.27) or -DQ2 (DQA1*0501-DQB1*0201) (P(chi(2)) = 0.46). Thus, the HERV-K(C4) insertion is not associated with type I diabetes in Germans.