Aortic valve reconstruction with use of pericardial leaflets in adults with bicuspid aortic valve disease: early and midterm outcomes

In this study, we retrospectively analyzed the outcomes of adults with bicuspid aortic valve (BAV) disease who underwent aortic valve reconstructive surgery (AVRS), consisting of replacement of the diseased BAV with 2 or 3 pericardial leaflets plus fixation of the sinotubular junction for accurate and constant leaflet coaptation. From December 2007 through April 2013, 135 consecutive patients (mean age, 49.2 ± 13.1 yr; 73.3% men) with symptomatic BAV disease underwent AVRS. Raphe was observed in 84 patients (62.2%), and the remaining 51 patients had pure BAV without raphe. A total of 122 patients (90.4%) underwent 3-leaflet reconstruction, and 13 (9.6%) underwent 2-leaflet reconstruction. Concomitant aortic wrapping with an artificial graft was performed in 63 patients (46.7%). There were no in-hospital deaths and 2 late deaths (1.5%); 6 patients (4.4%) needed valve-related reoperation. The 5-year cumulative survival rate was 98% ± 1.5%, and freedom from valve-related reoperation at 5 years was 92.7% ± 3.6%. In the last available echocardiograms, aortic regurgitation was absent or trivial in 116 patients (85.9%), mild in 16 (11.9%), moderate in 2 (1.5%), and severe in one (0.7%). The mean aortic valve gradient was 10.2 ± 4.5 mmHg, and the mean aortic valve orifice area index was 1.3 ± 0.3 cm(2)/m(2). The 3-leaflet technique resulted in lower valve gradients and greater valve areas than did the 2-leaflet technique. Thus, in patients with BAV, AVRS yielded satisfactory early and midterm results with low mortality rates and low reoperation risk after the initial procedure.

Transvenous transcatheter valve-in-valve implantation after bioprosthetic tricuspid valve failure

We describe the case of a 38-year-old man with a history of metastatic testicular cancer who had undergone multiple thoracic surgical procedures, including tricuspid valve replacement with a bioprosthetic valve as a result of tricuspid involvement of his malignancy. He presented at our outpatient cardiology clinic with worsening fatigue, shortness of breath, and peripheral edema, investigation of which revealed severe tricuspid bioprosthesis stenosis with central regurgitation. Because of the patient's medical history, he was considered to be a high-risk surgical candidate. Therefore, transcatheter tricuspid valve-in-valve implantation of a 26-mm Edwards Sapien(®) valve was attempted through a transjugular approach. The procedure restored tricuspid valvar competence and substantially improved the patient's symptoms. We discuss the technical aspects of this case and briefly review the usefulness of the valve-in-valve technique in the tricuspid position.

The quality of written instructions for dental prostheses in China

PURPOSE

To investigate the quality of written instructions for dental prostheses in China, including metal-ceramic fixed restorations and removable partial dentures (RPDs).

MATERIALS AND METHODS

A total of 1600 prepiloted questionnaires were distributed to five major commercial dental laboratories in different regions in China. The opinions of dental technicians on the written instructions provided by dentists were investigated. In addition, this study also revealed the technicians' responses to poorly written instructions.

RESULTS

Seven percent of the written instructions clarified the disinfection status of the impressions or casts, while 32% of the instructions provided general patient information (e.g., gender and age). In cases of metal-ceramic fixed restorations, percentages of written instructions specifying shade, ceramic veneering area, and margin design were 72%, 20%, and 9%, respectively. In fixed partial denture cases, 60% of written instructions provided the number of pontics, while 22% specified the pontic design. In the case of RPDs, 90% of instructions showed the type and position of clasps, 88% provided connector design, while 68% mentioned information regarding the artificial teeth. Dental technicians claimed that 78% of the written instructions involved were inadequately prescribed to some extent, but only about one-third of them would contact dentists for clarification.

CONCLUSIONS

Written instructions are not well prescribed in many cases. This situation may jeopardize the quality of prosthodontic treatment. It is necessary to shape responsible policy and mandatory professional guidelines for prosthodontic treatment procedures including dental laboratory services.

Polyaxial locking and compression screws improve construct stiffness of acetabular cup fixation: a biomechanical study

Bone ingrowth into uncemented acetabular components requires intimate cup-bone contact and rigid fixation, which can be difficult to achieve in revision hip arthroplasty. This study compares polyaxial compression locking screws with non-locked and cancellous screw constructs for acetabular cup fixation. An acetabular cup modified with screw holes to provide both compression and angular stability was implanted into a bone substitute. Coronal lever out, axial torsion and push-out tests were performed with an Instron testing machine, measuring load versus displacement. Polyaxial locking compression screws significantly improved construct stiffness compared with non-locked or cancellous screws. This increased construct stiffness will likely reduce interfacial micromotion. Further research is required to determine whether this will improve bone ingrowth in vivo and reduce cup failure.

Functional outcome following a large head total hip arthroplasty: A retrospective analysis of mid term results

BACKGROUND

One of the reasons that hip resurfacing and large head metal on metal (MOM) total hip arthroplasty (THA) became popular in Asia was the possible increased range of movement and thereby improved function of the hip joint. Due to concerns of MOM articulation an alternative bearing was sought. Hence, a shift from large head MOM to large head ceramic on ceramic (COC) was made. The aim of this study was to compare the functional outcome including range of motion (ROM) and dislocation rates following large head MOM and large head COC THA.

MATERIALS AND METHODS

Retrospectively, 39 primary THA with large head MOM with a mean age of 56 years (range 36-72 years) and average followup of 54 months (range 38-70 months) were compared with 23 primary THA with large head COC bearing with a mean age of 48 years (range 36-68 years) and an average followup of 18 months (range 12-26 months). Functional outcome was assessed using the Modified Harris Hip Score. Dislocation rate and ROM were compared.

RESULTS

Global ROM averaged 248 degrees with MOM group and 252 degrees with the COC group. One patient with metal bearing had dislocation at an average 3 year followup which required revision THA while there were no complications in the COC group. MHHS averaged 89 points in MOM and 94 in COC THR.

CONCLUSION

This study has shown that large head ceramic on ceramic THA is a good alternative to large head metal on metal THA with comparable dislocation rates and range of movements and without complications of metallosis in Asian patients.

Prospective five-year subsidence analysis of a cementless fully hydroxyapatite-coated femoral hip arthroplasty component

Early subsidence >1.5 mm is considered to be a predictive factor for later aseptic loosening of the femoral component following total hip arthroplasty (THA). The aim of this study was to assess five-year subsidence rates of the cementless hydroxyapatite-coated twinSys stem (Mathys Ltd., Bettlach, Switzerland).This prospective single-surgeon series examined consecutive patients receiving a twinSys stem at Maria Middelares Hospital, Belgium. Patients aged >85 years or unable to come to follow-up were excluded. Subsidence was assessed using Ein Bild Roentgen Analyse--Femoral Component Analysis (EBRA-FCA). Additional clinical and radiographic assessments were performed. Follow-ups were prospectively scheduled at two, five, 12, 24, and 60 months.In total, 218 THA (211 patients) were included. At five years, mean subsidence was 0.66 mm (95% CI: 0.43-0.90). Of the 211 patients, 95.2% had an excellent or good Harris Hip Score. There were few radiological changes. Kaplan-Meier analysis indicated five-year stem survival to be 98.4% (95% CI: 97.6-100%).Subsidence levels of the twinSys femoral stem throughout the five years of follow-up were substantially lower than the 1.5 mm level predictive of aseptic loosening. This was reflected in the high five-year survival rate.

Kinematic differences between gender specific and traditional knee implants

In the ongoing debate about gender-specific (GS) vs. traditional knee implants, there is limited information about patella-specific outcomes. GS femoral component features should provide better patellar tracking, but techniques have not existed previously to test this accurately. Using novel computed tomography and radiography imaging protocols, 15 GS knees were compared to 10 traditional knees, for the 6 degrees of freedom of the patellofemoral and tibiofemoral joints throughout the range of motion, plus other geometric measures and quality of life (QOL). Significant differences were found for patellar medial/lateral shift, where the patella was shifted more laterally for the GS femoral component. Neither group demonstrated patellar maltracking. There were no other significant differences in this well-functioning group.

First-in-man transfemoral transcatheter aortic valve replacement with the 29 mm Edwards SAPIEN XT valve

OBJECTIVES

To demonstrate the feasibility of transfemoral transcatheter aortic valve replacement (TAVR) with the 29 mm Edwards SAPIEN XT valve and Novaflex™ + delivery system through a 20F expandable sheath (eSheath™, Edwards Lifesciences, USA). In addition, to describe the use of the Novaflex + delivery system and expandable sheath.

BACKGROUND

TAVR has undergone significant advances in device technology resulting in smaller profile sheaths and delivery systems, allowing transfemoral delivery of a 29 mm valve.

METHODS

Twelve patients underwent transfemoral TAVR with the 29 mm Edwards SAPIEN XT valve and Novaflex + delivery system through a 20F expandable sheath. Baseline clinical and procedural characteristics are evaluated. In-hospital and 30-day outcomes are reported according to Valve Academic Research Consortium criteria.

RESULTS

All patients were male with a mean aortic annulus diameter of 25.0 ± 1.1 mm and 25.9 ± 1.2 mm, on transesophageal echocardiography and multidetector computerized tomography, respectively. Mean iliofemoral minimal luminal diameter (MLD) was 8.0 ± 0.8 mm. Successful deployment of the valve occurred in 11 out of 12 patients. Valve embolization occurred in one patient. Aortic valve area increased from 0.7 ± 0.2 to 2.0 ± 0.5 cm(2) (P < 0.001). There were two major vascular complications; however, there were no in-hospital or 30-day neurological events, need for pacemaker insertion, or mortality.

CONCLUSIONS

Transfemoral TAVR with the 29 mm Edwards SAPIEN XT valve and Novaflex + delivery system through a 20F expandable sheath was feasible with acceptable short-term outcomes.

Pan-nitinol occluder and special delivery device for closure of patent ductus arteriosus: a canine-model feasibility study

The aim of this study was to evaluate a new type of occluder for patent ductus arteriosus. Patent ductus arteriosus was established in a canine model by anastomosing a length of autologous jugular vein to the descending aorta and the left pulmonary artery in an end-to-side fashion. Transcatheter closure of each patent ductus arteriosus was performed on 10 dogs, which were then monitored for as long as 6 months with aortography, echocardiography, and histologic evaluation. Transcatheter closure with use of the novel pan-nitinol device was successful in all canine models. Postoperative echocardiography showed that the location and shape of the occluders were normal, without any residual shunting. Further histologic evaluation confirmed that the occluder surface was completely endothelialized 3 months after implantation. Transcatheter patent ductus arteriosus closure with the pan-nitinol occluder can be performed safely and successfully in a canine model and shows good biological compatibility and low mortality rates.

The Sorin Freedom SOLO stentless tissue valve: early outcomes after aortic valve replacement

We prospectively evaluated the hemodynamic performance of the SORIN Freedom SOLO aortic bioprosthesis, a stentless bovine pericardial valve designed for supra-annular implantation. Forty patients (mean age, 71.68 ± 5.25 yr; 29 men) with severe aortic stenosis underwent aortic valve replacement from January 2008 through August 2009. Patients were evaluated by transthoracic echocardiography and clinical examination, both preoperatively and again at 6 and 24 postoperative months. Peak and mean transvalvular gradients, end-diastolic and end-systolic diameters, interventricular septal and posterior wall thicknesses, indexed volumes of ventricular mass, degrees of aortic regurgitation, and left ventricular ejection fractions were calculated echocardiographically. The valves were implanted with single polypropylene sutures. In the early postoperative period, 1 patient (2.5%) died of multiorgan failure. The mean aortic cross-clamp time was 86.05 ± 34.2 min. Echocardiographic peak gradients were 84.54 ± 16.85 mmHg (preoperative), 29.59 ± 6.27 mmHg (6 mo postoperative), and 24.33 ± 4.67 mmHg (24 mo postoperative) (P < 0.001); left ventricular mass indices were 176.26 ± 39.98 g/m(2) (preoperative), 139.21 ± 30.1 (6 mo postoperative), and 120.51 ± 23.88 g/m(2) (24 mo postoperative) (P < 0.001). During follow-up, the maximum aortic insufficiency recorded was trace, and no valve dysfunctions were observed. Temporary thrombocytopenia was documented in all patients during early postoperative follow-up (lowest level at day 3); recovery to preoperative levels occurred by day 10. The Freedom SOLO aortic bioprosthesis is an easy-to-implant valve with excellent hemodynamic performance. The thrombocytopenia appears to be a transient laboratory finding.

Continuous-flow total heart replacement device implanted in a 55-year-old man with end-stage heart failure and severe amyloidosis

We implanted a continuous-flow total heart replacement device in a 55-year-old man who had severe end-stage heart failure due to amyloidosis and no other options for treatment. The device was composed of 2 modified HeartMate II ventricular assist pumps. After the implantation, our patient recovered normal neurologic function and was able to converse with his family and work on his computer. He died of multisystem organ failure caused by severe amyloidosis 5 weeks after the implantation. During the past 6 years, we have been developing and testing various technological iterations for total heart replacement in our animal laboratory and have achieved survival periods as long as 90 days in calves. We describe the development, preclinical trials, and adaptation for human use of the modified HeartMate II apparatus, as well as its role in our patient's survival.

Tuna cornea as biomaterial for cardiac applications

Among available biomaterials, cornea is almost completely devoid of cells and is composed only of collagen fibers oriented in an orderly pattern, which contributes to low antigenicity. Thunnus thynnus, the Atlantic bluefin tuna, is a fish with large eyes that can withstand pressures of approximately 10 MPa. We evaluated the potential of this tuna cornea in cardiac bioimplantation. Eyes from freshly caught Atlantic bluefin tuna were harvested and preserved in a fixative solution. Sterilized samples of corneal stroma were embedded in paraffin and stained with hematoxylin and eosin, and the histologic features were studied. Physical and mechanical resistance tests were performed in comparison with bovine pericardial strips and porcine mitral valves. Corneal material was implanted subcutaneously in 7 rats, to evaluate in vivo calcification rates. Mitral valves made from tuna corneal leaflets were implanted in 9 sheep. We found that the corneal tissue consisted only of parallel collagen fibers without evidence of vascular or neural structures. In tensile strength, the tuna corneal specimens were substantially similar to bovine pericardium. After 23 days, the rat-implanted samples showed no calcium or calcium salt deposition. Hydrodynamic and fatigue testing of valve prototypes yielded acceptable functional and long-term behavioral results. In the sheep, valvular performance was stable during the 180-day follow-up period, with no instrumental sign of calcification at the end of observation. We conclude that low antigenicity and favorable physical properties qualify tuna cornea as a potential material for durable bioimplantation. Further study is warranted.

The 37-year durability of a Björk-Shiley Delrin-disc aortic valve prosthesis

We report the exceptional longevity of a Björk-Shiley Delrin-disc prosthetic aortic valve that had been implanted in a man who underwent surgical correction of an ascending aortic aneurysm 37 years later. Upon explantation of the valve, the Delrin disc had only shallow abrasion on the ventricular surface, and none on the aortic surface. We discuss the soundness and durability of this valve in our patient, in contrast with its short functional prosthetic life in other patients. The 37-year lifespan of this patient's Björk-Shiley Delrin-disc valve is among the longest reported.

First human trial of KW39 slotted-tube stents: for percutaneous coronary intervention

The KW39 stent is a balloon-expandable, stainless-steel, slotted-tube stent, newly designed to adjust to the shape of the coronary arteries. We evaluated the clinical efficacy and safety of KW39 stent-based percutaneous coronary interventions in human native coronary arteries. A total of 105 patients (110 lesions), with a diagnosis of stable angina, acute coronary syndrome, or asymptomatic myocardial ischemia, were included in this prospective study. The primary endpoint was the target-lesion revascularization rate at the conclusion of a 6-month follow-up period. The secondary endpoints were the rates of technical and procedural success and the rate of major adverse cardiac events (defined as cardiac death, myocardial infarction, and target-lesion revascularization) in the course of the 6 months after stent placement. The 6-month target-lesion revascularization rate was 8.6%. The KW39 stent was highly satisfactory in regard to all secondary endpoint comparisons. Binary (>50%) in-stent restenosis was observed in 22 of 110 lesions (20%). The mean diameter stenosis at 6 months after percutaneous coronary intervention was 35.1% ± 14.4%, and the mean late lumen loss was 1.06 ± 0.48 mm. Stepwise multivariate analysis showed probable causal associations between adverse local environments for stent implantation and the subsequent need for target-lesion revascularization. We conclude that KW39 stent implantation was technically feasible and clinically safe in the patient population that we studied. The results of the safety endpoints, including cardiac death and acute myocardial infarction, were acceptable.

Unicompartmental knee resurfacing: enlarged tibio-femoral contact area and reduced contact stress using novel patient-derived geometries

Advances in imaging technology and computer-assisted design (CAD) have recently enabled the introduction of patient-specific knee implant designs that hold the potential to improve functional performance on the basis of patient-specific geometries, namely a patient-specific sagittal and coronal curvature, as well as enhanced bone preservation. The objective of this study was to investigate the use of a novel implant design utilizing a patient specific sagittal J-curve on the femoral component combined with a novel constant, patient-derived femoral coronal curvature and to assess tibio-femoral contact area and contact stress on a femur matched curved tibial polyethylene insert. Mean contact area and standard deviations were 81+/-5, 96+/-5 and 74+/-4 mm(2) for the heel strike, toe off and mid-stance positions, respectively. Mean contact stress and standard deviations were 23.83+/-1.39, 23.27+/-1.14 and 20.78+/-0.54 MPa for the heel strike, toe off and mid-stance positions, respectively. Standard deviations of the measurements were small, not exceeding 6-7% confirming the consistency of loading conditions across different flexion angles. The results were comparable to those reported for standard, off-the-shelf fixed-bearing implants with paired femoral and tibial geometries. These data show that a constant coronal curvature can be applied to a patient-specific implant by measuring coronal curvatures across the femoral condyle in each patient and by deriving an average curvature. This novel approach combines unique benefits of patient-specific geometry with proven design concepts for minimizing polyethylene wear.

Endoluminal abdominal aortic aneurysm repair: the latest advances in prevention of distal endograft migration and type 1 endoleak

Endovascular abdominal aortic aneurysm repair (EVAR) is an attractive alternative to open surgical repair. Distal endograft migration and type 1 endoleak are recognized to be the 2 main complications of EVAR. First-generation endografts had a stronger propensity for distal migration, modular component separation, thrombosis, and loss of structural integrity. Substantial progress has been made in recent years with 2nd- and 3rd-generation devices to prevent these complications. Some of the most common predictors of endograft failure are angulated and short infrarenal necks, large-diameter necks, and thrombus in the aneurysmal sac. The purpose of this study is to describe and review our experience in using innovative techniques and a newer generation of endografts to prevent distal migration and type 1 endoleak in patients with challenging infrarenal neck anatomy. The use of these innovative EVAR techniques and the new generation of endografts in patients with challenging infrarenal neck anatomy has yielded encouraging procedural and intermediate-term results.

Stentless xenograft implantation in aortic position in a 7-year-old girl

Disease or dysfunction of the aortic valve in pediatric patients presents a substantial challenge. Valve preservation, even if not the definitive solution, is always optimal. Successful repair will enable somatic growth and avoid repeated valve replacement and the need for systemic anticoagulation. When repair of the aortic valve is not possible in pediatric patients, replacement of the valve requires the most suitable (or, often, the least unsuitable) choice for each patient. The limitations of the typical replacement options (pulmonary autografts, mechanical valves, stented bioprostheses, and homografts) have led us to explore the use of stentless xenografts. Herein, we present a case of aortic valve replacement with a stentless porcine xenograft in one of the youngest and smallest patients reported to date. Use of the xenograft enabled a proper fit with a small aortic annulus, precluded the need for subsequent systemic anticoagulation, and averted a transvalvular gradient and the creation of 2-valve disease. We believe that the stentless porcine xenograft is feasible for use in pediatric patients who require aortic valve replacement.

Percutaneous closure of mitral paravalvular leak via retrograde approach: with use of the Amplatzer duct occluder II and without a wire loop

The gold-standard treatment for prosthetic-valve paravalvular leakage is surgery to repair or replace the valve; however, the morbidity and mortality rates cannot be ignored, and some patients are poor surgical candidates. The percutaneous closure of such defects is possible, and different devices are being used for this purpose. In almost all instances, a femorofemoral or femorojugular wire loop is constructed to deliver the closure device. Herein, we present the case of a 61-year-old man in whom a mitral paravalvular leak was successfully closed with use of the Amplatzer Duct Occluder II, via retrograde approach under 3-dimensional transesophageal echocardiographic guidance, without the use of a wire loop. To the best of our knowledge, this is the 1st report of retrograde device deployment without the construction of an arteriovenous wire loop, and the 1st case in which the Amplatzer Duct Occluder II was used for the percutaneous closure of a mitral paravalvular leak.

Use of the IntuiTrak stent-graft delivery system for percutaneous abdominal aortic aneurysm exclusion: initial single-center experience

The exclusion of abdominal aortic aneurysms by endovascular techniques has enabled the treatment of patients who have high-risk comorbidities that preclude safe surgical repair. Since the development of the unibody bifurcated endovascular stent-graft for abdominal aortic aneurysm exclusion, remarkable technological improvements have facilitated stent-graft delivery and reduced the required size of the access site. Our initial institutional experience with the use of the Endologix IntuiTrak Express Delivery System for the Powerlink stent-graft (in 7 patients) shows that the device is suited for percutaneous use without sequelae. Herein, we describe the IntuiTrak system and the successful results of its use: we achieved percutaneous access and closure in all 7 patients, with no conversions to open repair or vascular exposure.

Continuous-flow total artificial heart supports long-term survival of a calf

The development and clinical use of continuous-flow left ventricular assist devices (LVADs) stimulated our interest in developing a total heart replacement with continuous-flow rotary blood pumps. We constructed a continuous-flow total artificial heart (CFTAH) from 2 HeartMate II axial-flow LVADs and used this CFTAH to replace the native heart of a calf. The purpose of this experiment was to study the effects of total continuous flow on physiologic parameters at rest and during exercise after the animal recovered from surgery. We monitored pulmonary and systemic pump performance, and we assessed arterial blood gases, hemodynamic and biochemical variables, and neurohormone levels during the 7 weeks of CFTAH support. At day 36 after CFTAH implantation, the calf was exercised on a treadmill at increasing speeds for 40 minutes; total oxygen consumption, pump flow, blood pressure, and respiratory rate were monitored. Baseline hematologic levels were altered postoperatively but returned to normal by 2 weeks. We saw no signs of hemolysis or thrombosis during CFTAH support. The calf had a normal physiologic response to treadmill exercise. The animal gained weight and appeared to function normally during the study. The CFTAH operated within design specifications throughout the study. Homeostasis, end-organ and vasomotor function, and the ability to exercise are not adversely affected by 7 weeks of totally pulseless circulation in a calf.

A modification to the Manouguian aortoplasty for biological valve implantation in patients with small (< or =19 mm) aortic anuli--rationale and benefit

Enlargement of a small aortic root using the Manouguian technique for biological valve implantation can be challenging when rigid, severely calcified noncoronary parts of the aortic anulus are encountered in combination with outsized heights of interleaflet triangles. To maximize the efficacy of the Manouguian technique, we applied a modification--the rationale, technical details, and benefits of which we describe herein.

The Berlin Heart EXCOR in an 11-year-old boy: a bridge to recovery after myocardial infarction

When a donor heart is not available during the end stage of heart failure, the implantation of a ventricular assist device is the only therapeutic alternative. Many such devices are designed to provide circulatory support to adults, but very few are available for children and infants, especially in the United States. In children, implantation of ventricular assist devices that are designed for adults carries a high risk of complications, because the low stroke volumes that must be used can result in inadequate pump washout and excessive thromboembolic risk. Herein, we report the case of an 11-year-old boy with congenital heart defects who experienced acute myocardial infarction. Prolonged support with the Berlin Heart excor Pediatric ventricular assist device served as a bridge to recovery. The period after device implantation was challenging, because of the need for prolonged inotropic support, continuous mechanical ventilation, the number of reoperations, and the occurrence of sepsis. Nevertheless, after 29 days, the patient's heart recovered, and the device was explanted. He was discharged from the hospital, in good condition, 30 days after removal of the excor device.

St. Jude Medical and CarboMedics mechanical heart valves in the aortic position: comparison of long-term results

We designed this study to compare long-term results of St. Jude Medical and CarboMedics mechanical heart valves in the aortic position. We retrospectively analyzed the results of 174 consecutive patients who received either a St. Jude (n=80) or a CarboMedics (n=94) mechanical aortic valve from March 1992 through October 2004. The follow-up rate was 97.7%. The mean follow-up duration for the St. Jude group was 79.3 +/- 35.0 and for the CarboMedics group, 70.0 +/- 34.3 months. The cumulative follow-up was 523.8 and 530.1 patient-years, respectively The 30-day mortality rates for the St. Jude and CarboMedics patients were 1.3% and 3.2%, respectively. The actuarial survival rate for the St. Jude group at 138.0 +/- 4.7 months was 75.9% +/- 0.1% and for the CarboMedics group at 130.8 +/- 4.8 months was 69.8% +/- 0.1% (P=NS). There was no structural valve deterioration in either group. Freedom from thromboembolic events was 87.7% for the St. Jude group and 83.0% for the CarboMedics group (P=NS). Freedom from bleeding events for the St. Jude group was 93.6% and for the CarboMedics group, 89.7% (P=NS). The results obtained from this study indicate that standard St. Jude Medical and CarboMedics aortic valve prostheses offer similar excellent clinical performance. Definitive judgment must await trials that are extensive, randomized, and prospective.

Experience with the Edwards MIRA mechanical bileaflet valve in the aortic and mitral positions

The Edwards MIRA bileaflet mechanical prosthesis, a heart valve not yet available in the United States, is designed with a unique hinge mechanism, curved leaflets, and thin titanium housing. We performed this study to investigate its clinical performance and postoperative hemodynamic results. We implanted 58 Edwards MIRA prostheses in 51 patients in the aortic (n = 18), mitral (n = 26), and aortic and mitral (n = 7) positions. Patients' ages ranged from 25 to 84 years (mean age, 53.7 +/- 13.6). Operative mortality was 2% (n = 1), and late mortality was 4% (n = 2). Thromboembolic events were observed in 2 patients (valve thrombosis in 1 and a cerebrovascular event in 1). There were no complications related to anticoagulation. No signs of valvular dysfunction or paravalvular leakage were observed. Peak transvalvular gradients of the aortic prostheses ranged from 24.25 +/- 5.32 mmHg for the 21-mm valve to 11 +/- 1.41 mmHg for the 25-mm valve. The effective orifice area ranged from 1.99 +/- 0.12 cm2 for the 21-mm valve to 2.44 +/- 0.17 cm2 for the 25-mm valve. The mean transvalvular gradients of the mitral prostheses ranged from 5.85 +/- 2.91 mmHg for the 27-mm valve to 4.5 +/- 0 mmHg for the 31-mm valve. The effective orifice area ranged from 2.31 +/- 0.03 cm2 for the 27-mm valve to 2.64 +/- 0.05 cm2 for the 33-mm valve. These preliminary data suggest good hemodynamic function and a low rate of valve-related complications in the use of the Edwards MIRA mechanical prosthesis.

Mathematical Model analysis of Wallstent and Aneurx: dynamic responses of bare-metal endoprosthesis compared with those of stent-graft

We performed this study in order to analyze the mechanical properties of bare-metal Wallstent endoprostheses and of AneuRx stent-grafts and to compare their responses to hemodynamic forces. Mathematical modeling, numerical simulations, and experimental measurements were used to study the 2 structurally different types of endoprostheses. Our findings revealed that a single bare-metal Wallstent endoprosthesis is 10 times more flexible (elastic) than is the wall of the aneurysmal abdominal aorta. Graphs showing the changes in the diameter and length of the stent when exposed to a range of internal and external pressures were obtained. If the aorta is axially stiff and resists length change, a force as large as 1 kg can act in the axial direction on the aortic wall. If the stent is not firmly anchored, it will migrate. In contrast, a fabric-covered, fully supported, stent-graft such as the AneuRx is significantly less compliant than the aorta or the bare-metal stent. During each cardiac cycle, the stent frame tends to move due to its higher elasticity, while the fabric resists movement, which might break the sutures that join the fabric to the frame. Elevated local transmural pressure, detected along the prosthesis graft, can contribute to material fatigue.

First human case of retrograde transcatheter implantation of an aortic valve prosthesis

The transcatheter route is an emerging approach to treating valvular disease in high-risk patients. The 1st clinical antegrade transcatheter placement of an aortic valve prosthesis was reported in 2002. We describe the first retrograde transcatheter implantation of a new aortic valve prosthesis, in a 62-year-old man with inoperable calcific aortic stenosis and multiple severe comorbidities. Via the right femoral artery, a Cook introducer was advanced into the abdominal aorta. The aortic valve was crossed with a straight wire, and a pigtail catheter was advanced into the left ventricle to obtain pressure-gradient and anatomic measurements. An 18-mm valvuloplasty balloon was then used to predilate the aortic valve. Initial attempts to position the prosthetic valve caused a transient cardiac arrest. Implantation was achieved by superimposing the right coronary angiogram onto fluoroscopic landmarks in the same radiographic plane. A balloon-expandable frame was used to deliver the valve. After device implantation, the transvalvular gradient was <5 mmHg. The cardiac output increased from 1 to 5 L/min, and urine production increased to 200 mL/h. The patient was extubated on the 2nd postimplant day. Twelve hours later, he had to be reintubated because of respiratory distress and high pulmonary pressures. His condition deteriorated, and he died of biventricular failure and refractory hypotension on day 5. Despite the severe hypotension, valve function was satisfactory on echo-Doppler evaluation. In our patient, retrograde transcatheter implantation of a prosthetic aortic valve yielded excellent hemodynamic results and paved the way for further use of this technique in selected high-risk patients.

End-stage heart failure with multiple intracardiac thrombi: a rescue strategy

The use of ventricular assist devices as a bridge to transplantation has become a widely used option for patients with end-stage heart failure. In contrast to total artificial hearts, ventricular assist devices support the failing heart by bypassing one or both ventricles. In certain cases (myocardial tumors, graft failure, transplant rejection, endocarditis, intracardiac thrombus formation), however, it may be advantageous to excise the heart and replace it with an artificial device. Total artificial hearts are intracorporeal devices designed for this purpose. Unfortunately, some patients are too small or are, for other reasons, ineligible for a total artificial heart. We describe the case of a 55-year-old woman who had ischemic cardiomyopathy and thrombus formation in all 4 cardiac chambers. To reduce the risk of thromboembolic events, we elected to replace her heart completely with 2 extracorporeal ventricular assist devices. The heart was excised via a median stemotomy approach, and the outflow cannulae (from device to patient) were connected to both atrial remnants. The 2 inflow cannulae (from patient to device) were anastomosed end-to-end to the aorta and the pulmonary artery, respectively. After attaining a flow of more than 5 L, the 2 extracorporeal assist devices effectively and efficiently performed the work of the native heart. Thus re-established, organ perfusion was improved by this mechanically driven circulation, as signified by an initial decrease in creatinine and blood urea nitrogen levels. The patient, however, did not recover from postoperative neurological dysfunction and died of respiratory insufficiency and multiple-organ failure on the 26th postoperative day.

Aortic insufficiency in a patient with Marfan syndrome after aortic root reconstruction with a tailored-sinus graft

A patient with Marfan syndrome underwent valve-preserving aortic root reconstruction with a Robicsek-Thubrikar graft. Intraoperative transesophageal echocardiography showed aortic insufficiency after extracorporeal circulation was discontinued. Placing 3 subcommissural annuloplasty sutures corrected the severe aortic insufficiency. Herein, we discuss the mechanism and prevention of aortic regurgitation after aortic root replacement with a new graft that contains pre-designed aortic sinuses.

Improved device for sutureless aortic anastomosis applied in a case of cancer

To reduce the time needed for clamping or circulatory arrest (or both) during substitution of a prosthesis for the thoracic aorta, we developed an expandable device that can be used with any commercially available prosthetic graft to enable sutureless aortic anastomosis. Improvements upon a previous version of the device include the use of nickel-titanium alloy (Nitinol) instead of stainless steel. This, together with an improved wire-looping design, now enables continuous control of diameter, even when the device is in contact with blood. A further improvement consists of 4 metallic hooks on the outer surface, which enable firm fixation to the aortic stump. In March 2001, a 47-year-old man was admitted to our institution for evaluation of left upper-lobe bronchogenic adenocarcinoma that had infiltrated the distal aortic arch and upper descending aorta. Re-staging of the neoplasm ruled out distant metastasis. We resected the infiltrated aortic wall en bloc with the upper lobe. The expandable device enabled the distal anastomosis of the aortic prosthesis to be performed easily, in less than 3 minutes. The main advantages of this device are an easier, quicker anastomosis and the absolute prevention of suture-line hemorrhage (no suture line). The expandable device overcomes the drawbacks of the intraluminal ringed prosthesis used in the past.

Implantation of cryopreserved allograft pulmonary monocusp patch to treat nonthrombotic femoral vein incompetence

We implanted cryopreserved allograft monocusp patches made from cadaveric pulmonary arteries to correct nonthrombotic valvular insufficiency of the common femoral vein in patients with chronic venous ulcers. Thirty-eight patients with 40 ulcers of longer than 3 years' duration underwent valvular repair of the common femoral vein from September 1995 through November 2001. We studied ulcer healing and competence of the monocusp patches using duplex ultrasonography Three patients with a total of 4 ulcers were lost to follow-up; therefore, 35 patients with 36 ulcers were available for examination. Twenty-four ulcers healed, and 12 did not. Of the 24 healed ulcers, 5 recurred. Four of the 5 ulcers were treated, 3 by monocusp patch replacement and 1 by iliac vein dilation and stenting. All such recurrent ulcers healed. The 5th recurrent ulcer was not treated, because the patient refused therapy Therefore, of the 24 ulcers that healed initially, 23 were healed at the end of the study Of the 12 unhealed ulcers, 4 were treated: 2 by ligation of incompetent perforating veins, 1 by saphenous vein ligation and partial stripping, and 1 by monocusp replacement. All 4 ulcers healed. The other 8 patients, all of whom had severe monocusp insufficiency, refused therapy. Therefore, of the 12 ulcers that did not heal initially, 4 were healed after additional treatment. No implanted monocusp patch developed clots. The ulcers remained healed when the prostheses remained competent. We conclude that monocusp patches can restore valvular competence to the femoral vein in patients who have primary valve insufficiency. In such patients, venous ulcers heal rapidly after prosthesis implantation if the monocusp remains competent and if there is no severe incompetence of the superficial venous system or of perforating veins.

Mitral valve replacement with the SORIN valve. Long-term follow-up of 1,161 patients

From 1 March 1977 through 31 December 1987, 1,252 patients underwent mitral valve replacement with a SORIN-Biomedica 60 degrees tilting-disc prosthesis at our institution. Hospital mortality was 7.3% (91 patients); prosthesis-related deaths, expressed as a percentage of hospital mortality, accounted for 12.1% of these early deaths. The 1,161 patients who survived hospitalization have been followed up for a total of 4,835 patient-years (range, 1 to 128 months; mean, 50.4 +/- 27.3 months). Forty-three (3.7%) of these patients were lost to follow-up. The late mortality was 6.3% (1.5% +/- 0.2% per patient-year), and the 10-year actuarial survival rate, excluding hospital mortality, was 89.1% +/- 1.6%. The 10-year actuarial (and linearized) rates of freedom from valve-related complications were as follows: embolism, 94.4% +/- 1.0% (0.93% +/- 0.1% per patient-year); thrombosis of the prosthesis, 99.8% +/- 0.1% (0.06% +/- 0.03% per patient-year; hemorrhage, 93.7% +/- 1.5% (0.95% +/- 0.1% per patient-year); prosthetic valve endocarditis, 99.3% +/- 0.3% (0.14% +/- 0.05% per patient-year); reoperation, 90.6% +/- 2.1% (1.1% +/- 0.2% per patient-year); and overall complications, 76.6% +/- 2.5% (2.9% +/- 0.2% per patient-year). No structural deterioration was noted. These data not only confirm our previous reports concerning the reliability and durability of the SORIN prosthesis but also reveal a significant reduction, over the long term, in the overall incidence of valve-related complications.

Aortic replacement with sutureless intraluminal grafts

To avoid the anastomotic complications and long cross-clamp times associated with standard suture repair of aortic lesions, we have implanted sutureless intraluminal grafts in 122 patients since 1976. Forty-nine patients had disorders of the ascending aorta, aortic arch, or both: their operative mortality was 14% (7 patients), and the group's 5-year actuarial survival rate has been 64%. There have been no instances of graft dislodgment, graft infection, aortic bleeding, or pseudoaneurysm formation. Forty-two patients had disorders of the descending aorta and thoracoabdominal aorta: their early mortality was 10% (4 patients), and the group's 5-year actuarial survival rate has been 56%. There was 1 early instance of graft dislodgment, but no pseudoaneurysm formation, graft erosion, aortic bleeding, intravascular hemolysis, or permanent deficits in neurologic, renal, or vascular function. Thirty-one patients had the sutureless intraluminal graft implanted in the abdominal aortic position: their early mortality was 6% (2 patients), and the 5-year actuarial survival rate for this group has been 79%. There were no instances of renal failure, ischemic complication, postoperative paraplegia, pseudoaneurysm, or anastomotic true aneurysm. Our recent efforts have been directed toward developing an adjustable spool that can adapt to the widest aorta or the narrowest aortic arch vessel; but in the meanwhile, the present sutureless graft yields shorter cross-clamp times, fewer intraoperative complications, and both early and late results as satisfactory as those afforded by traditional methods of aortic repair.

Asymptomatic strut fracture in DeBakey-Surgitool aortic valves: incidence, management, and metallurgic aspects

From August 1971 through November 1972, we implanted 62 Model 2 DeBakey-Surgitool aortic valve prostheses in 62 patients, 4 of whom later had clinically asymptomatic strut fractures. In 1 case, the patient died suddenly, and autopsy revealed detachment of the ball-cage; in each of the other 3 cases, fractures of 2 struts close to the base of the prosthesis were diagnosed fluoroscopically, and the patients underwent successful reoperation. The interval between implantation and reoperation ranged from 11 months to 16 years, 9 months. In 1 patient, retrospective study of chest radiographs revealed that the fracture had been present for 2(1/2) years. Larger valves (>/= A6) were affected significantly more often than smaller ones. We performed metallurgic analysis of 1 prosthesis: results revealed strut wear from fatigue cracking and secondary abrasion. Strut fracture was also promoted by suspension of the cage at right angles to the prosthetic ring and by use of a pyrolytic carbon ball in a titanium cage (i.e., an occluder harder than its holder). Patients with DeBakey-Surgitool aortic valve prostheses should undergo annual radiologic examinations to enable early detection of strut fractures. Prophylactic valve replacement is not indicated.

A polyester intravascular stent for maintaining luminal patency: a gross and microscopic study of the device's incorporation, early maturation, and thrombogenicity

Over the past 3 years, we have developed a polyester mesh stent designed to preserve luminal patency in cases of dissecting aortic aneurysm and to maintain arterial patency after angioplasty. To study the stent's incorporation into the aortic wall and to test its thrombogenicity, we implanted the device in the abdominal aortas of ten dogs. The device was compressed and inserted into a 10-Fr sheath, which was introduced through the femoral artery into the aorta. Once liberated from the sheath and fully expanded within the aorta, the stent measured 10 cm in length and 8 mm in outer diameter. Each animal was followed up clinically until it was killed at intervals ranging from 1 week to 6 months after implantation. The aorta was excised, and tissue incorporation was evaluated grossly, as well as with light and scanning electron microscopy. In all cases, the arteries and side branches were found to be widely patent. At 3 weeks, the stent already had become firmly adherent to the vessel, owing to the ingrowth of fibrous tissue and endothelium through the mesh. The thrombus-free surface area, assessed planimetrically, was minimal during the early part of the study but rose to a plateau of 80% by the second month. Each specimen was subjected to indium-111 platelet scanning. The polyester mesh initially stimulated much platelet deposition, but this phenomenon decreased markedly over a 2-month period. In summary, our experience showed that an intraluminal polyester mesh stent could be inserted into the aorta via the retrograde arterial route and could effectively line the inner surface of the vessel. Within 2 months, healing was nearly complete and thrombogenicity was minimal.