Homografts In Patients Research Articles

Impact of pressure recovery on the assessment of pulmonary homograft function using Doppler ultrasound.

Relevant pressure recovery (PR) has been shown to increase functional stenotic aortic valve orifice area and reduce left ventricular load. However, little is known about the relevance of PR in the pulmonary artery. The study examined the impact of PR using 2D-echocardiography in the pulmonary artery distal to the degenerated homograft in patients after Ross surgery. Ninety-two patients with pulmonary homograft were investigated by Doppler echocardiography (mean time interval after surgery 31 ± 26 months). PR was measured as a function of pulmonary artery diameter determined by computed tomography angiography. Homograft orifice area, valve resistance, and transvalvular stroke work were calculated with and without considering PR. PR decreased as the pulmonary artery diameter increased (r=-0.69, p < 0.001). Mean PR was 41.5 ± 7.1% of the Doppler-derived pressure gradient (Pmax ), which resulted in a markedly increased homograft orifice area (energy loss coefficient index [ELCOI] vs. effective orifice area index [EOAI], 1.3 ± 0.4 cm2 /m2 vs. 0.9 ± 0.4 cm2 /m2 , p < 0.001). PR significantly reduced homograft resistance and transvalvular stroke work (822 ± 433 vs. 349 ± 220 mmHg × ml, p < 0.0001). When PR was considered, the correlations of the parameters used were significantly better, and 11 of 18 patients (61%) in the group with severe homograft stenosis (EOAI <0.6 cm2 /m2 ) could be reclassified as moderate stenosis. Our results showed that the Doppler measurements overestimated the degree of homograft stenosis and thus the right ventricular load, when PR was neglected in the pulmonary artery. Therefore, Doppler measurements that ignore PR can misclassify homograft stenosis and may lead to premature surgery.

Oversize It: Valuable Advice for Larger Right Ventricle-to-Pulmonary Artery Conduits

Longevity of Large Aortic Allograft Conduits in Tetralogy With Major Aortopulmonary CollateralsThe Annals of Thoracic SurgeryPreviewAppropriate conduit selection for right ventricle (RV)-to-pulmonary artery (PA) connection has been extensively studied, with older implantation age, pulmonary (vs aortic) homografts, and true sizing associated with increased longevity. Notably, patients with PA arborization abnormalities (ie, major aortopulmonary collateral arteries [MAPCAs]) are reported to require earlier and more frequent conduit interventions. We aim to understand the behavior of large-diameter aortic homografts in patients with MAPCAs, which are programmatically utilized at our institution. Full-Text PDF

Longevity of Large Aortic Allograft Conduits in Tetralogy With Major Aortopulmonary Collaterals

BackgroundAppropriate conduit selection for right ventricle (RV)-to-pulmonary artery (PA) connection has been extensively studied, with older implantation age, pulmonary (vs aortic) homografts, and true sizing associated with increased longevity. Notably, patients with PA arborization abnormalities (ie, major aortopulmonary collateral arteries [MAPCAs]) are reported to require earlier and more frequent conduit interventions. We aim to understand the behavior of large-diameter aortic homografts in patients with MAPCAs, which are programmatically utilized at our institution. MethodsThis is a single-center retrospective cohort study including all children less than 12 years of age who underwent RV-PA connection using an aortic homograft greater than or equal to 16 mm diameter between 2002 and 2019, with a primary outcome of freedom from any RV-PA reintervention and a secondary outcome of freedom from surgical reintervention. Patients were grouped by absolute and indexed conduit sizes for further analysis. ResultsA total of 336 conduits were followed for a median of 3.0 years; transcatheter (n = 30) or surgical (n = 35) reintervention was performed on 64 conduits. Estimated freedom from reintervention and surgical replacement was 84% and 90% at 5 years. Younger age and smaller absolute conduit size were associated with earlier reintervention, but conduit Z-score (median 3.5) was not associated with outcome. ConclusionsThe programmatic use of oversized aortic homograft RV-PA conduits in the surgical repair of MAPCAs provides a focused experience that demonstrates similar longevity to reported best alternatives. Secondarily, conduit oversizing may improve durability and enables an increased likelihood of nonoperative reintervention.

Outcomes of Isolated Pediatric Small Intestine Transplants Using Vascular Homografts

Introduction: Pediatric intestinal transplantation has changed recently with more isolated small intestine transplants being performed in small children instead of combined liver-intestine transplants. Consequently, surgical techniques have changed, requiring a frequent use of vascular homografts of small caliber, the impact of which on outcomes is unknown. Methods: Among 106 pediatric intestine and multivisceral transplants performed at our center since 2003, 39 recipients of an isolated small intestine graft were reviewed. Four patients transplanted between 2003 and 2005 with insufficient medical records and two patients with follow-up <1 year were excluded. The remaining 33 pts, including 4 retransplants (16M, 17F, median age 3.3 y [range 1.2-17.2], median weight 14.2 kg [8.1-56]) were included in this study. Grafts were monitored with Doppler of the stoma and angiography when necessary. Patients with hypercoagulable state received systemic anticoagulation from the time of graft reperfusion. Outcome parameters were thrombotic complications and graft survival. Results: 25/33 grafts (76%) were reperfused “centrally” (aorta and vena cava), 24 of them via vascular homograft. The other 8 grafts were reperfused via native superior mesenteric artery and vein. Overall, 28/33 (85%) patients required both arterial and venous homografts from the same donor (donor's median age 1.1 y [2mo-23 y], median weight 10 kg [14.7-48.5]), mainly iliac or carotid artery and iliac or innominate vein, respectively. Post-transplant, there were 3 acute thromboses at the anastomosis of the arterial homograft (2 central and one mesenteric) on post-operative day 0, 2 and 13 and one venous homograft thrombosis on POD 7 requiring urgent percutaneous thrombolysis and/or operative thrombectomy resulting in 2 peri-operative graft salvages and 2 graft losses. Three out of 4 thromboses occurred in patients with primary hypercoagulable state, including the 2 graft losses. Overall, at a median of 4.1 years (1–10.2) from transplant, 29/33 (88%) patients are alive with 26/33 (79%) functioning grafts. Conclusion: In our series 2/33 (6%) pediatric isolated intestine grafts were lost due to thrombotic complications of the vascular homograft in patients with hypercoagulable state. The procurement of intact, size-matched donor vessels and post-transplant anticoagulation are critical.

The Year 2011 in Interventional Cardiology

DOI: 10.5935/abc.20130238 Dear Editor, We are delighted to show Arquivos Brasileiros de Cardiologia readers a review of the most relevant studies on Interventional Cardiology published in Revista Espanola de Cardiologia in the last two years. In relation to national protocols of emergency transfer for primary percutaneous coronary intervention in ST elevation myocardial infarction patients, we have published two papers from northern Galicia and the Southern Metropolitan area of Barcelona. Of importance, the implementation of both programs resulted in an increase in the number of patients receiving primary angioplasty1,2. We have also published important studies regarding transcatheter aortic valve implantation, a hot topic in interventional cardiology. Lopez-Otero et al3 reported the experience of three Spanish hospitals with the use of the axillary approach in patients who have contraindication to the femoral approach. They showed that the axillary approach using the CoreValve® was safe and efficient for selected patients, with excellent results in terms of success implantation and in-hospital and 30-day mortality. Lopez-Otero et al4 also published the joint experience of four hospitals regarding safety and effectiveness of the treatment of degenerated aortic homograft in patients refused for surgery. They showed that transcatheter treatment of degenerated aortic homografts and aortic insufficiency was safe and effective. Hernandez-Antolin et al5 compared the results obtained in transfemoral implantation of an Edwards-SAPIEN or CoreValve® aortic valve prosthesis in patients with severe aortic stenosis and a high surgical risk. They showed that in-hospital mortality, the complication rate and medium-term outcomes were similar with the two devices. The only difference observed was a higher implantation success rate with the CoreValve®, although at the expense of a greater frequency of atrioventricular block. In the intracoronary imaging field, Jimenez-Quevedo et al6 investigated the clinical consequences and predictive factors of the change in the type of plaque as assessed by serial intracoronary ultrasound in type II diabetic patients with known coronary artery disease. They showed that qualitative changes in mild stenosis documented by intracoronary ultrasound in type II diabetics were associated with suboptimal secondary prevention. Also with intracoronary ultrasound, Medina et al7 studied plaque distribution in the coronary bifurcation and the prevalence of carina involvement. They showed plaque at the carina in one-third of the bifurcations. The incidence of plaque was higher in those bifurcations, with the minimal lumen area point distal to the carina, and was associated with a lower incidence of damage to the side branch ostium.

Stentless aortic bioprostheses: their role in the treatment of aortic endocarditis should not be underestimated

We read with great interest the comprehensive review article of Funder [1] on the clinical and experimental data surrounding the use of stentless aortic bioprostheses and fully agree with his conclusions. There is no doubt that they are ideal substitutes in patients with small aortic roots to prevent patient–prosthesis mismatch. In this context, they should be implanted in a ‘fullroot’ type of technique to minimize the postoperative aortic regurgitation that may occur due to distortion of the prosthesis [2] and to facilitate both prosthesis over-sizing and the optimization of haemodynamic results [3]. However, we were surprised that Funder did not comment on the value of stentless valves in the context of aortic endocarditis, particularly in patients with root abscesses and prosthetic valve endocarditis. Homografts have been the gold-standard for valve and root replacement in aortic endocarditis for a long time. Although they result in excellent haemodynamics and a low incidence of re-infection after surgery, the need for homograftrelated reoperation should not be underestimated and has been reported to be around 20% at 2 years, most often due to aortic regurgitation [4]. In addition, in these patients, for whom surgery is most often urgent, availability is limited, leading to delay in treatment. In 2003, Siniawski et al. [5] reported on their results using stentless bioprostheses in the setting of complex aortic endocarditis and made a comparison with their experience using homografts. Early mortality, freedom from re-infection and postoperative haemodynamics were not different between the two groups. However, they saw additional benefits of the stentless prosthesis, in that the surgery itself has a more standardized and therefore possibly easier technique. Moreover, limited availability, which may result in delayed surgery using homografts, is not an issue with stentless bioprostheses. If stentless valves are equivalent early after surgery, the question remains of how they compare with homografts in the longer term? Yacoub et al. [6] recently reported the outcomes of a prospective randomized trial including aortic root replacement using Freestyle stentless bioprostheses (Medtronic Inc., Minneapolis, MN, USA) and homografts. Over a median followup of 7.6 years, a significantly higher freedom from valve dysfunction in the stentless group (86 vs 37%) was noted. Consequently, reoperations due to structural valve degeneration were more common after homograft implantation (0 vs 10%). We conclude therefore, that the early outcome of stentless bioprostheses is comparable with homografts in patients suffering from aortic valve endocarditis. As long-term durability and freedom from reoperation are improved using stentless bioprostheses, and because their availability is not restricted, they are ideal substitutes, particularly in patients with complex aortic valve endocarditis.

Venovenous extracorporeal membrane oxygenation using a single cannula in patients with pulmonary hypertension and atrial septal defects

DISCUSSION Takedown of a Glenn shunt has been reported, but it is uncommon. In particular, there is a paucity of information on take-down and reconstruction of a left-sided Glenn in patients with atrial situs solitus. Coloni and colleagues describe using ringed and non-ringed PTFE grafts, as well as a conduit made from autologous or bovine pericardium to reconstruct the SVC and left brachiocephalic veins. Mahesh and Ratnatunga reported reconstruction of the SVC with aortic and pulmonary homograft in patients with SVC occlusion due to benign or malignant pathology.

How to choose the best available homograft to reconstruct the right ventricular outflow tract

How to choose the best available homograft to reconstruct the right ventricular outflow tract

Performance of SynerGraft Decellularized Pulmonary Homograft in Patients Undergoing a Ross Procedure

In the Ross aortic valve replacement (AVR), a pulmonary allograft normally replaces the autotransplanted pulmonary valve. Despite the Ross advantages vs other AVR procedures, there has been a small but unpredictable risk of early structural allograft valve deterioration, usually manifested by shrinkage and right ventricular outflow tract obstruction. This study analyzed our results of the Ross AVR using a new CryoValve SynerGraft (CryoLife Inc, Kennesaw, GA) decellularized pulmonary allograft (SGDPA) and compared it with the standard cryopreserved allograft (SCA) used during the same period. Between 2000 and 2009, 29 patients received a SGDPA and 34 received the SCA during Ross AVR. Patients were a mean age at implant of 28.6 ± 16.0 years (range, 4 months to 58 years). Retrospective data included reported adverse events, and the most recent hemodynamic data were collected. No early or late deaths or significant morbid events occurred during the mean follow-up of 4.9 ± 2.7 years (range, 2 months to 9 years). No patient required conduit reoperation. The median peak gradient at discharge was 12 mm Hg and was not significant at last follow-up. No deterioration in conduit valve function occurred in the SGDPA group. Mild conduit regurgitation developed in several SCA patients, and one patient had moderate regurgitation. No patient reached our definition of conduit dysfunction (peak gradient: 40 mm Hg or >2+ regurgitation). The SGDPA conduit is an alternative to the SCA for the Ross AVR. The early clinical and hemodynamic results are encouraging but were not significantly different from the SCA. SynerGraft technology may provide a more durable option for patients who need right ventricular outflow tract reconstruction. Further long-term follow-up is needed to see if this decellularization process improves long-term allograft durability.

In Situ Revascularisation with Silver-coated Polyester Prostheses and Arterial Homografts in Patients with Aortic Graft Infection – A Prospective, Comparative, Single-centre Study

In Situ Revascularisation with Silver-coated Polyester Prostheses and Arterial Homografts in Patients with Aortic Graft Infection – A Prospective, Comparative, Single-centre Study

In Situ Revascularisation with Silver-coated Polyester Prostheses and Arterial Homografts in Patients with Aortic Graft Infection – A Prospective, Comparative, Single-centre Study

Objective The aim of our study was to evaluate the effectiveness of in situ revascularisation with the use of arterial homografts and silver-coated prostheses in the treatment of aortic graft infection. Materials A total of 77 consecutive patients (74 males, three females, mean age: 58 years), hospitalised between 2001 and 2008, were enrolled into the study. Patients were assigned to three groups: group 1 ( n = 24) – fresh arterial homograft with subsequent immunosuppression, group 2 ( n = 26) – fresh arterial homograft without immunosuppression and group 3 ( n = 27) – silver-coated prosthesis. Methods The course of infection was assessed by scintigraphy with 99mTechnetium-labelled leucocytes, Duplex–Doppler ultrasound, angio-computed tomography (CT) and microbiological examination. Results The mean follow-up was 22.8 (±10.1) months. There was a significant decrease in leucocyte accumulation around the graft among all groups (group 1: p = 0.012, group 2: p = 0.006 and group 3: p = 0.021). The postoperative mortality rate in groups 1,2 and 3 was 8%, 23% and 11%, respectively. The postoperative morbidity was 35% in group 2, 16% in group 1 and 7% in group 3. Conclusion Our study suggests that silver-coated prostheses can be as effective as arterial allografts in the treatment of infections of vascular prostheses.

Early results of right ventricular-pulmonary artery conduits in patients under 1 year of age.

Management strategies for the repair of many complex heart defects require the implantation of a valved conduit between the right ventricle (RV) and the pulmonary artery (PA), often using aortic or pulmonary homograft valves. Their limited availability, however, has led to the development and use of new conduits. We retrospectively compared our experience with small homografts in patients of less than 1 year of age with the TissueMed bioprosthetic valved conduit. From March 1994 to November 1997 29 patients in their first year of life underwent conduit implantation for complex heart defects. These were retrospectively reviewed in order to determine the incidence of death or conduit stenosis. Seventeen patients received homografts and 12 TissueMed conduits. Diagnoses and operative details including conduit size were similar in the two groups and in all cases complete repair of the underlying defect was carried out. Early post-operative mortality was 4/17 (23.5%) in the homograft group and 3/12 (25%) in the TissueMed group. Echo Doppler evaluation within 1 month of operation showed no right ventricular outflow tract (RVOT) obstruction in any of the survivors. In the TissueMed group 8/9 (77%) survivors have gone on to develop significant RVOT obstruction within 12 months of operation. There have been three late deaths in this group all related to severe RVOT obstruction. Two patients died during an attempt at balloon dilatation and one patient died of progressive right heart failure. Five patients had successful replacement of the TissueMed conduit. One child remains well with no evidence of RVOT obstruction. At operation to replace conduit, or at autopsy, the stenoses were related to the deposition of fibrous tissue at the anastomotic suture lines. In the homograft group none of the survivors developed RVOT obstruction during the first 12 months post-operatively. There was one late death (non-cardiac in origin) and one child is awaiting conduit replacement 40 months after initial implantation for obstruction. The homograft is a satisfactory conduit for re-establishment of RV-PA continuity in infancy. Further work needs to be undertaken in order to elucidate the mechanisms of early graft failure in bioprosthetic conduits if these are to be a suitable alternative for RV outflow reconstruction in infants.

Cryopreserved homografts in the pulmonary position: determinants of durability

Background. The cryopreserved homograft has emerged as the pulmonary conduit of choice for the repair of many congenital heart defects. It is also used for pulmonary valve replacement in the Ross procedure. Because of a wide range of patient ages and diagnoses, the risk of homograft failure may vary. Methods. We reviewed 185 consecutive pulmonary position implants performed between September 1985 and January 1999. We examined three age groups: patients less than 1 year of age (n = 53), patients 1 to 10 years of age (n = 46), and patients more than 10 years of age (n = 86). Results. Five-year Kaplan-Meier homograft survival was 25%, 61%, and 81% for the groups, respectively ( p < 0.02). Smaller homograft size, younger patient age, and truncus arteriosus were risk factors for homograft failure in univariate analysis ( p < 0.05). Smaller homograft size was the only predictor for homograft failure in multivariate analysis ( p < 0.001). Twenty of 99 implants in patients less than 10 years old underwent transcatheter intervention. The 3-year Kaplan-Meier implant survival of this group (79%) was not different from those who did not undergo intervention (77%, p = 0.84). Survival of aortic and pulmonary homografts in patients less than 10 years of age was not different ( p = 0.35). Ross procedure implants appear to have optimal survival (94%) at 5 years. Non-Ross implants in patients more than 10 years of age have 76% 5-year Kaplan-Meier survival, which is not different from Ross patients ( p = 0.33). Conclusions. Small homografts have limited durability. Aortic homografts perform as well as pulmonary homografts in young patients. Once patients receive an “adult-size” homograft, at approximately 10 years of age, risk for implant failure approximates that of patients undergoing the Ross procedure. Transcatheter interventions, when indicated, may prolong homograft life.

Tricuspid valve replacement with cryopreserved mitral homograft in patients with hemodynamic impairment

Tricuspid valve replacement with cryopreserved mitral homograft in patients with hemodynamic impairment

Outcome of pulmonary and aortic homografts for right ventricular outflow tract reconstruction

To determine late patient outcome and homograft durability, we reviewed 326 patients who received aortic ( n = 230) or pulmonary ( n = 118) cryopreserved homografts for right ventricular outflow reconstruction between January 1985 and October 1993. Patient survival, including operative mortality, 5 years after the operation was similar between the two groups (ulmonary homograft 86%, aortic homograft 80%; p = not significant by log-rank test). However, 5-year freedom from homograft failure was significantly better for pulmonary homografts (94% versus 70%), p < 0.01 by log-rank test). Late calcification was evaluated by chest roentgenography and echocardiography. Overall, 20% of aortic homografts became moderately or severely calcified compared with 4% of pulmonary homografts ( p < 0.001). Twenty-six percent of aortic homografts in children 4 years old or younger had moderate or severe obstruction associated with calcification, whereas only 11% of aortic homografts in patients over 4 years of age had calcific obstruction ( p < 0.01). No late deaths among patients receiving pulmonary homografts were related to graft failure; two late deaths in the aortic homograft group were homograft related. Risk factors for patient mortality and homograft failure (defined as either need for homograft replacement because of homograft failure ( p < 0.0001), but type of homograft was not correlated with patient mortality. Age 4 years or younger was a significant risk factor for homograft failure ( p < 0.0001), but type of homograft was not correlated with patient mortality. Age 4 years or younger was a significant risk factor for both mortality ( p < 0.01) and homograft failure ( p = 0.03) in aortic homograft recipients but not in pulmonary homograft recipients. These results indicate that both aortic and pulmonary homografts provided excellent intermediate-term patient survival after right ventricular outflow tract reconstruction, but pulmonary homografts are more durable than aortic homografts with less calcification and obstruction, especially among children 4 years old or younger. (J T HORAC C ARDIOVASC S URG 1995; 109: 509-18)

Long-term results with vein homograft in femoro-distal arterial reconstructions

There still is a need for an alternative to autologous vein especially for infra-inguinal vascular reconstructions. Since 1984 we have used a denatured venous homograft in patients in whom the saphenous vein was either absent or unsuitable. One hundred and five homografts were implanted in the femoro-popliteal and 51 in the femoro-infrapopliteal position. The results obtained were satisfactory, with a 5-year cumulative patency (life-table method) of 53% overall, 68.4% in patients with disabling claudication, and 42% in those with critical ischaemia. The cumulative aneurysm rate was rather high, at 18% after 3 years and 58% after 5 years. An excellent limb salvage rate of 85% was achieved in patients with critical ischaemia. The management of graft aneurysms and the indications for reconstructive surgery with a denatured venous homograft are discussed.

Skin autografts and homografts in patients with the lymphoma mycosis fungoides

In a series of autografts done in 14 patients with mycosis fungoides (MF), normal skin could be transplanted without difficulty to either normal recipient sites or sites involved with lymphoma. In contrast, transplantation of skin involved with lymphoma was infrequently successful. Mycosis fungoides tumor tissue was never transferred successfully, and in no instance was transfer of disease accomplished by transplantation. Possible reasons for these findings are presented. Homografts were done in 18 patients with mycosis fungoides. The initial take pattern was the same as in the autograft series. Sixteen of the 18 patients rejected normal skin homografts within a 23-day period. The 2 patients retaining grafts for longer periods were in terminal stages of their illness. Thus, no depression of this parameter of delayed hypersensitivity capacity was identified with this lymphoma.

Immunological Studies and Behavior of Husband and Foreign Homografts in Patients with Chorionepithelioma

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IMMUNOLOGICAL STUDIES AND BEHAVIOUR OF HUSBAND AND FOREIGN HOMOGRAFTS IN PATIENTS WITH CHORIONEPITHELIOMA

IMMUNOLOGICAL STUDIES AND BEHAVIOUR OF HUSBAND AND FOREIGN HOMOGRAFTS IN PATIENTS WITH CHORIONEPITHELIOMA