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1.
Am J Transplant ; 17(10): 2559-2566, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28510318

RESUMO

Cardiac transplantation remains the only definitive treatment for end-stage heart failure. Transplantation rates are limited by a shortage of donor hearts. This shortage is magnified because many hearts are discarded because of strict selection criteria and concern for regulatory reprimand for less-than-optimal posttransplant outcomes. There is no standardized approach to donor selection despite proposals to liberalize acceptance criteria. A donor heart selection conference was organized to facilitate discussion and generate ideas for future research. The event was attended by 66 participants from 41 centers with considerable experience in cardiac donor selection. There were state-of-the-art presentations on donor selection, with subsequent breakout sessions on standardizing the process and increasing utilization of donor hearts. Participants debated misconceptions and established agreement on donor and recipient risk factors for donor selection and identified the components necessary for a future donor risk score. Ideas for future initiatives include modification of regulatory practices to consider extended criteria donors when evaluating outcomes and prospective studies aimed at identifying the factors leading to nonacceptance of available donor hearts. With agreement on the most important donor and recipient risk factors, it is anticipated that a consistent approach to donor selection will improve rates of heart transplantation.


Assuntos
Transplante de Coração , Sociedades Médicas , Doadores de Tecidos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos
2.
J Am Coll Cardiol ; 26(3): 737-42, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7642868

RESUMO

OBJECTIVES: This study analyzes our experience with transplantation of small donor hearts in a subgroup of moribund patients who could not be bridged to transplantation with mechanical assist devices. BACKGROUND: The major problem facing transplant programs in the United States is the lack of donor heart availability. One method of expanding the donor pool may be to liberalize the criteria for an acceptable donor heart. METHODS: We analyzed the growth and adaptation of 14 undersized and 14 conventionally sized donor hearts over a period of 10 weeks after heart transplantation. The left ventricular systolic and diastolic diameters, septal and posterior wall thicknesses, left ventricular mass calculated by the Penn convention and left ventricular ejection fraction were obtained by M-mode and two-dimensional echocardiography and documented by a single reader in blinded manner. Echocardiographic measurements were obtained before implantation and at 5 and 10 weeks after orthotopic heart transplantation. RESULTS: The mean (+/- SD) donor/recipient weight ratios were 0.53 +/- 0.06 for undersized hearts and 0.98 +/- 0.05 for normal-sized hearts. All 28 patients received similar immunosuppressive regimens, including intravenous steroids, cyclosporine and azathioprine. The length of hospital stay after transplantation did not vary significantly between the two groups. All the patients had at least one rejection episode during the 10-week study period. There was a tendency toward higher pulmonary pressures in undersized hearts, which was not statistically significant. Heart rate was significantly higher for undersized hearts, due in part to the use of theophylline or terbutaline to maintain tachycardia. There was a significant increase in left ventricular systolic and diastolic dimensions in undersized hearts compared with conventionally sized hearts. Undersized hearts increased in left ventricular mass over the 10-week period, whereas the conventionally sized donor hearts did not change between 5 and 10 weeks. CONCLUSIONS: In undersized hearts the increase in left ventricular mass and internal dimensions, with preservation of the posterior/septal wall thickness ratio, suggests that the left ventricle adapts to the larger recipient circulation early after transplantation. Despite denervation and a mismatched load, undersized transplanted hearts adapt appropriately to their new hemodynamic milieu.


Assuntos
Adaptação Fisiológica , Transplante de Coração/fisiologia , Coração/fisiopatologia , Doadores de Tecidos , Adulto , Idoso , Análise de Variância , Ecocardiografia/instrumentação , Ecocardiografia/estatística & dados numéricos , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/cirurgia , Transplante de Coração/diagnóstico por imagem , Transplante de Coração/métodos , Transplante de Coração/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/fisiologia , Philadelphia , Cuidados Pós-Operatórios/métodos , Estudos Prospectivos , Fatores de Tempo
3.
Cardiovasc Res ; 37(2): 424-31, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9614497

RESUMO

OBJECTIVE: To examine the contribution of reverse mode sodium-calcium (Na-Ca) exchange to contractions in isolated left-ventricular myocytes from failing human heart. METHODS: Low resistance patch pipettes were used to dialyze cells with Na-free or high-Na pipette solution ([Na]pipette = 0 and 20 mmol/L, respectively) to reduce or enhance Na-Ca exchange. Whole-cell membrane-potential, membrane-current and cell-shortening data were simultaneously acquired during whole-cell voltage clamp protocols. Thapsigargin (100 nmol/L) and nifedipine (1 mumol/L) were also used to inhibit sarcoplasmic reticulum (SR) Ca-ATPase and L-type Ca channels, respectively. RESULTS: Two types of contractions were observed. Rapid phasic contractions were seen in both Na-free and high-Na cells. Slow tonic contractions were seen only in high-Na cells. Phasic contractions demonstrated bell-shaped voltage dependence over the voltage range that corresponds to the activity of the L-type Ca channel. Although the voltage dependence of phasic contractions were similar Na-free and high-Na cells, phasic contractions in high-Na cells were larger than phasic contractions in Na-free cells. Phasic contractions were sensitive to inhibition of SR Ca-ATPase and L-type Ca channels. Tonic contractions were not inhibited by either thapsigargin or nifedipine. In thapsigargin-treated high-Na cells, tonic contraction magnitude increased exponentially with test-potential. CONCLUSIONS: The increases in phasic contraction magnitude observed in high-Na cells compared to Na-free cells were most likely due to increased SR Ca loading resulting from increased reverse-mode Na-Ca exchange. Our results also suggest that tonic contractions in high-Na cells were mediated by Ca entry via reverse-mode Na-Ca exchange and were not the result of either SR Ca release or L-type Ca channel activity.


Assuntos
Insuficiência Cardíaca/metabolismo , Contração Miocárdica , Miocárdio/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , ATPases Transportadoras de Cálcio/antagonistas & inibidores , Células Cultivadas , Citosol/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Contração Miocárdica/efeitos dos fármacos , Nifedipino/farmacologia , Retículo Sarcoplasmático/metabolismo , Sódio/metabolismo , Tapsigargina/farmacologia
4.
Transplantation ; 71(7): 1000-3, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11349708

RESUMO

BACKGROUND: Transjugular intrahepatic shunts are widely used for the management of variceal bleeding. Complications such as stent misplacement or migration may occur. METHODS: We describe the management of a transjugular intrahepatic shunts stent that migrated across the tricuspid valve in a patient with Child-Pugh category C cirrhosis. RESULTS: An attempt at percutaneous retrieval of the stent was unsuccessful. Due to the unacceptably high risk for mortality from open heart surgery with cardiopulmonary bypass in the setting of cirrhosis, stent removal was deferred until the time of orthotopic liver transplantation. The procedures were performed successfully, and the patient made a good recovery. CONCLUSION: Surgical stent extraction and valve repair can be performed safely along with orthotopic liver transplantation in carefully selected patients with end-stage liver disease.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Migração de Corpo Estranho/cirurgia , Cirrose Hepática/cirurgia , Transplante de Fígado , Derivação Portossistêmica Transjugular Intra-Hepática/instrumentação , Stents , Migração de Corpo Estranho/complicações , Migração de Corpo Estranho/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Torácica
5.
Transplantation ; 71(8): 1137-46, 2001 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-11374416

RESUMO

BACKGROUND: We investigated the role of apoptosis (programed cell death) in the pathogenesis of chronic rejection. METHODS: Epicardial coronary arteries from cardiac allografts with chronic rejection were examined for apoptosis by the TUNEL assay. Double labeling was carried out using anti-CD3, anti-CD68, and anti-von Willenbrand factor (vWF) monoclonal antibodies. Additional immunostaining was carried using anti-Fas, anti-Fas-L, and anti-Bcl-2 monoclonal antibodies. Apoptosis-associated oligonucleosomal DNA degradation was assessed by DNA agarose gel electrophoresis. The transcription level of apoptosis-related caspase genes were determined using microarrays. RESULTS: Apoptotic cells (TUNEL+) were detected within the arterial wall and in perivascular areas. Double labeling demonstrated that apoptotic cells included T cells (CD3+), monocyte/macrophages (CD68+), and vascular endothelial cells (VWF+). Numbers and densities of TUNEL+ cells did not correlate with the degree of arterial stenosis. Apoptosis-associated oligonucleosomal DNA degradation was assessed by agarose gel electrophoresis of DNA, which showed DNA fragments of approximately 180 bp and multimers thereof (DNA laddering gel), which are characteristic for DNA fragmentation in apoptotic cells. Microarray analysis demonstrated that the apoptosis related caspases 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, were all transcribed (caspases 8, 9, and 10 were highly up-regulated). These results are consistent with the involvement of apoptosis in chronic rejection. Immunoreactivity for Fas/Fas-L was present at the sites of apoptotic cells. Immunoreactivity for Bcl-2 was present in areas with very few apoptotic cells. CONCLUSIONS: Apoptotic cells include T cells, monocyte/macrophages, and endothelial cells. Apoptosis, likely through the Fas/Fas-L system, is involved in the pathogenesis of chronic rejection in cardiac allografts.


Assuntos
Apoptose , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Transplante de Coração/imunologia , Transplante de Coração/patologia , Adulto , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Complexo CD3/análise , Doença Crônica , Vasos Coronários/imunologia , Vasos Coronários/patologia , Fragmentação do DNA , Proteína Ligante Fas , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Glicoproteínas de Membrana/análise , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/patologia , Proteínas Proto-Oncogênicas c-bcl-2/análise , Linfócitos T/imunologia , Linfócitos T/patologia , Receptor fas/análise
6.
J Thorac Cardiovasc Surg ; 99(2): 256-62; discussion 262-3, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2299863

RESUMO

Deep median sternotomy wound infection is a significant source of morbidity after cardiac operations. Accepted approaches in treating this complication include débridement with either sternal closure over an irrigation system or open dressings and closure by secondary intention. Muscle flaps are often used in subsequent procedures for wound closure. A single-stage procedure was developed to eliminate irrigation, open wound management, or reoperation for muscle flap closure. This approach consists of débridement and immediate closure with a pectoral musculocutaneous flap. The following report describes 31 patients treated by such a method. Compared with results of previous techniques in treating sternal wound infections, hospital study is decreased, fewer reoperations are needed, and patient management is simplified.


Assuntos
Infecção da Ferida Cirúrgica/terapia , Procedimentos Cirúrgicos Cardíacos , Humanos , Esterno/cirurgia
7.
J Thorac Cardiovasc Surg ; 104(2): 224-8, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1495283

RESUMO

We tested the ability of University of Wisconsin solution to extend hypothermic preservation of the nonperfused heart during orthotopic baboon allotransplantation. Seven baboons received hearts after cardioplegia and storage (4 degrees C) with University of Wisconsin solution, with a preservation time of 14.2 +/- 1.6 hours. One animal died as a result of a technical error. Six survivors were immunosuppressed for 45 days and then put to death. Preservation did not alter heart weight or histologic features according to light and electron microscopy. Animals were weaned from bypass and returned to their cages without intravenous support within 3.9 +/- 0.8 hours. Weekly biopsies, electrocardiograms, enzyme analyses, echocardiograms, and right heart catheterizations demonstrated excellent cardiac function. University of Wisconsin solution can extend hypothermic cardiac preservation and has no deleterious effects on long-term myocardial function (up to 45 days). This study validates the rationale for human trials with preservation and storage in University of Wisconsin solution toward the goal of improving and prolonging donor heart preservation.


Assuntos
Soluções Cardioplégicas , Transplante de Coração/fisiologia , Soluções para Preservação de Órgãos , Preservação de Órgãos/métodos , Soluções , Adenosina , Alopurinol , Animais , Soro Antilinfocitário/uso terapêutico , Ciclosporina/uso terapêutico , Glutationa , Sobrevivência de Enxerto/fisiologia , Terapia de Imunossupressão , Insulina , Papio , Rafinose , Linfócitos T/imunologia , Fatores de Tempo
8.
J Thorac Cardiovasc Surg ; 103(4): 781-3, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1548921

RESUMO

UNLABELLED: Dehiscence rates of esophageal anastomoses are between 5% and 20%. Because small leaks between sutures might promote microabscess formation and lead to dehiscence, we postulated that a better initial physical seal might be beneficial. Reinforcement with laser activation of tissue sealant (LATS) is a new technique that has been shown to increase the bursting strength of anastomoses in other tissues. The tissue sealant is composed of 0.4 ml of hyaluronic acid and 0.2 ml of albumin, to which 3 drops of indocyanine green dye are added to give the sealant a peak absorbance of 805 nm, matching the wavelength (808 nm) of a small, hand-held diode laser. Since tissues do not absorb at this wavelength, laser energy is focused in the sealant, minimizing collateral thermal damage. To extend this concept, we assessed LATS in a canine model of esophageal closure. The esophagus was exposed via a right thoracotomy in 20 dogs, and two transverse incisions, 2 cm in length, were made in each esophagus (n = 40 closures). Both sites were closed with a single layer of interrupted 4-0 polyglycolic acid suture. Either the proximal or distal incision was randomly chosen to receive laser activation of tissue sealant. Tissue sealant was applied to the reapproximated edges of the hand-sewn closure, which was then exposed to diode laser energy. The end point was visible shrinking and desiccation of the sealant, which required about 2 minutes. Each esophagus was recovered at 0, 2, or 7 days postoperatively (n = 10, 5, and 5 dogs, respectively), bursting pressure was measured, and the closures were examined histologically. At all three time points LATS closures had significantly higher bursting pressures than control closures (time 0: 251 +/- 87 versus 105 +/- 46, p less than 0.0001; time 2 days: 296 +/- 36 versus 121 +/- 14, p less than 0.0013; time 7 days: 318 +/- 72 versus 197 +/- 60, p less than 0.0021). Histologic study revealed trace thermal injury, with regeneration of intact mucosal lining by 7 days. CONCLUSION: laser activation of tissue sealant is a simple technique that significantly increases the strength of esophageal closure and may reduce the prevalence of dehiscence.


Assuntos
Adesivos , Esôfago/cirurgia , Lasers , Deiscência da Ferida Operatória/prevenção & controle , Técnicas de Sutura , Animais , Cães , Esôfago/fisiologia , Distribuição Aleatória , Deiscência da Ferida Operatória/fisiopatologia , Resistência à Tração
9.
J Thorac Cardiovasc Surg ; 103(2): 194-8; discussion 198-9, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1735983

RESUMO

We have previously shown the safety and efficacy of University of Wisconsin solution for hypothermic preservation of the human donor heart in a pilot group of 16 transplant recipients. The present study is a randomized clinical trial comparing University of Wisconsin solution to conventional preservation using crystalloid cardioplegia and saline storage within a 4-hour limit of ischemia. Heart transplant recipients (n = 42) were randomized into two groups: those receiving hearts preserved by University of Wisconsin solution, the UWS group (n = 22), and those receiving hearts preserved in the conventional manner, the CCS group (n = 20). Recipient age, gender, heart disease, and preoperative inotropic support and donor age, gender, and mean ischemic time in hours (UWS 2 hours 36 minutes, range 1 hour 36 minutes to 2 hours 53 minutes; CCS 2 hours 20 minutes, range 1 hour 20 minutes to 2 hours 44 minutes; p = not significant) were similar. Significant differences observed between the two groups included (1) mean time (minutes) from reperfusion to achieve a stable rhythm, (2) need for intraoperative defibrillations, (3) need for transient cardiac pacing, and (4) integrated postoperative creatinine kinase and aspartate aminotransferase release over 48 hours. There was no difference in postoperative electrocardiogram, endomyocardial biopsy, or hemodynamics. One UWS patient died of sepsis and another of a ruptured cerebral aneurysm. UWS is safe for donor organ arrest and preservation despite high viscosity and potassium concentration. When compared with CCS hearts, hearts preserved in UWS regained electrical activity more rapidly and had better myocardial protection as demonstrated by enzymatic analysis. Further investigation is required to determine the effects of UWS preservation on long-term survival, to determine the prevalence of rejection and graft atherosclerosis, and to test the ability of UWS to extend donor ischemic time in human cardiac transplantation.


Assuntos
Transplante de Coração , Soluções para Preservação de Órgãos , Preservação de Órgãos , Compostos de Potássio , Soluções , Adenosina , Alopurinol , Soluções Cardioplégicas , Cardioversão Elétrica , Feminino , Glutationa , Humanos , Insulina , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Reperfusão Miocárdica , Potássio , Estudos Prospectivos , Rafinose
10.
J Heart Lung Transplant ; 19(7): 705-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10930821

RESUMO

Anastomotic Stenoses are well known as a complication of vascular and cardiovascular surgical procedures; such a lesion was encountered at the superior vena cava-right atrial anastomosis after cardiac transplantation. A balloon expandable stent was used to relieve this anastomotic constriction, employing a 16 mm diameter balloon to deliver a P304 stent. Stent placement resulted in complete relief of the patient's symptoms and facilitated the passage of bioptomes through the superior vena cava for subsequent biopsy procedures following cardiac transplantation.


Assuntos
Angioplastia com Balão/instrumentação , Oclusão de Enxerto Vascular/terapia , Átrios do Coração/cirurgia , Transplante de Coração/efeitos adversos , Stents , Síndrome da Veia Cava Superior/terapia , Veia Cava Superior/cirurgia , Anastomose Cirúrgica , Ecocardiografia Doppler , Oclusão de Enxerto Vascular/diagnóstico , Oclusão de Enxerto Vascular/etiologia , Átrios do Coração/diagnóstico por imagem , Insuficiência Cardíaca/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Flebografia , Síndrome da Veia Cava Superior/diagnóstico , Síndrome da Veia Cava Superior/etiologia , Veia Cava Superior/diagnóstico por imagem
11.
J Heart Lung Transplant ; 13(5): 905-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7803435

RESUMO

Orthotopic heart transplantation was performed in a 65-year-old man with a donor heart with Wolff-Parkinson-White Syndrome. An electrophysiologic study performed 7 days after transplantation showed a left-lateral accessory pathway that exhibited only anterograde conduction. Radiofrequency ablation of the bypass tract was successfully performed, and no evidence of recurrence was found at 12 months' follow-up. We suggest that potential donors with known electrophysiologic abnormalities that are amenable to catheter ablation techniques should be considered for orthotopic heart transplantation, thus broadening the potential donor pool.


Assuntos
Ablação por Cateter , Transplante de Coração , Síndrome de Wolff-Parkinson-White/cirurgia , Idoso , Nó Atrioventricular/fisiopatologia , Mapeamento Potencial de Superfície Corporal , Fascículo Atrioventricular/fisiopatologia , Estimulação Cardíaca Artificial , Ablação por Cateter/métodos , Eletrocardiografia , Seguimentos , Átrios do Coração/inervação , Sistema de Condução Cardíaco/fisiopatologia , Ventrículos do Coração/inervação , Humanos , Masculino , Doadores de Tecidos , Síndrome de Wolff-Parkinson-White/fisiopatologia
12.
J Heart Lung Transplant ; 13(4): 681-7; discussion 685-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7947885

RESUMO

Triiodothyronine deficiency after brain death can result in progressive deterioration of cardiac function in potential organ donors. We report on the use of triiodothyronine replacement in improving myocardial function, allowing the use of donor hearts that might have been considered unsuitable for transplantation. From July to September 1992, of 24 organ procurements and transplantations, six donors were receiving high doses of inotropes with elevated left-sided filling pressures. Donor characteristics were as follows: five were male donors and one was a female donor, with mean age 16.50 +/- 7.50 years (8 to 30 years), mean weight 49.17 +/- 13.64 kg (25 to 63 kg), average time from clinical brain death to procurement 94.50 +/- 73.53 hours (49 to 240 hours), and two donors had arrest periods of up to 10 minutes. Despite large inotrope infusions, echocardiograms showed depressed left ventricular function (mean ejection fraction 39.17 +/- 5.85) and hemodynamic instability was present with elevated ventricular filling pressures. Triiodothyronine replacement (maximal dose 0.6 microgram/kg) was initiated an average of 139.17 +/- 32.00 minutes (115 to 185 minutes) before procurement. At the time of procurement, ventricular filling pressures were lower, hemodynamic condition stabilized, and pressor requirements decreased. Hearts were preserved in University of Wisconsin solution with a mean ischemic time of 188.83 +/- 36.86 minutes (149 to 237 minutes).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Transplante de Coração , Coração/efeitos dos fármacos , Soluções para Preservação de Órgãos , Doadores de Tecidos , Tri-Iodotironina/farmacologia , Adenosina , Adolescente , Alopurinol , Morte Encefálica/fisiopatologia , Soluções Cardioplégicas , Feminino , Glutationa , Transplante de Coração/fisiologia , Hemodinâmica/efeitos dos fármacos , Humanos , Insulina , Masculino , Preservação de Órgãos , Rafinose , Fatores de Tempo , Obtenção de Tecidos e Órgãos , Função Ventricular Esquerda/efeitos dos fármacos
13.
J Heart Lung Transplant ; 16(7): 765-73, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9257259

RESUMO

BACKGROUND: Left ventricular assist devices (LVAD) provide lifesaving circulatory support to patients awaiting heart transplantation. To date, the extent to which sustained mechanical unloading alters the phenotype of pathologic myocardial hypertrophy in dilated cardiomyopathy is unknown. METHODS: We examined left ventricular size, myocyte and myocardial immunoreactivity for atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in eight patients with advanced dilated cardiomyopathy before and after LVAD support. The mean duration of congestive heart failure was 18 +/- 5 months, and LVAD support averaged 42 +/- 4 days before heart transplantation. RESULTS: Echocardiographically determined left ventricular mass decreased from 505 +/- 83 to 297 +/- 52 gm (p < 0.05) during LVAD support, whereas minimum myocyte diameter decreased from 28.1 +/- 0.9 to 21.7 +/- 0.6 microns (p < 0.01) in transmural myocardial tissue specimens. Overall left ventricular ANP immunopositivity decreased from 48% at LVAD placement to 12% at transplantation (p < 0.05), whereas BNP immunopositivity decreased from 28% to 4% after LVAD support. Moreover, a gradient of ANP and BNP immunostaining from subendocardium to epicardium observed before mechanical unloading diminished after LVAD support. Analysis of the relationship between left ventricular mass and ANP immunopositivity revealed a close and highly significant correlation between these variables. CONCLUSIONS: These studies demonstrate remarkable left ventricular plasticity even in the presence of advanced cardiomyopathy. Parallel reductions in myocardial mass and myocyte size with reductions in ventricular ANP and BNP immunostaining indicate a novel regression of the phenotype of pathologic hypertrophy within the human myocardium after LVAD support.


Assuntos
Cardiomiopatia Dilatada/metabolismo , Coração Auxiliar , Miocárdio/metabolismo , Adolescente , Adulto , Fator Natriurético Atrial/metabolismo , Cardiomegalia/diagnóstico por imagem , Cardiomegalia/metabolismo , Cardiomegalia/fisiopatologia , Cardiomegalia/terapia , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/fisiopatologia , Cardiomiopatia Dilatada/terapia , Ecocardiografia Doppler , Endocárdio/metabolismo , Endocárdio/patologia , Feminino , Coração/fisiologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Peptídeo Natriurético Encefálico , Proteínas do Tecido Nervoso/metabolismo , Função Ventricular Esquerda/fisiologia
14.
J Heart Lung Transplant ; 13(3): 533-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8061031

RESUMO

A 29-year-old woman had an acute myocardial infarction 5 days after giving birth. Serial coronary angiography showed multiple progressive coronary artery dissections, which eventually involved both the right and left coronary trees. Persistent cardiogenic shock necessitated emergent orthotopic heart transplantation. Examination of the cardiectomy specimen confirmed the presence of multiple myocardial infarctions, coronary artery dissection, and fibromuscular dysplasia of the coronary arteries. Fibromuscular dysplasia combined with changes in the arterial ground substance and hormonal milieu attributable to pregnancy or parturition are proposed as possible causes of coronary artery dissection in this case.


Assuntos
Doença das Coronárias/complicações , Displasia Fibromuscular/complicações , Infarto do Miocárdio/etiologia , Período Pós-Parto , Adulto , Doença das Coronárias/patologia , Feminino , Displasia Fibromuscular/patologia , Transplante de Coração , Humanos , Infarto do Miocárdio/patologia , Ruptura Espontânea , Choque Cardiogênico/etiologia
15.
J Heart Lung Transplant ; 14(3): 429-35, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7654727

RESUMO

BACKGROUND: Sinus node dysfunction has been reported to occur in up to 50% of orthotopic heart transplant recipients, and oral theophylline has been used in an attempt to limit the morbidity associated with this abnormality. The purpose of this study was to evaluate the electrophysiologic effects of methylxanthines on sinus node function. METHODS: Sinus node testing performed in 26 patients before and after the infusion of 6 mg/kg of aminophylline. Thirteen of these patients had abnormal sinus node function at baseline, and thirteen had normal sinus node function. Sinus node dysfunction was diagnosed by a rhythm other than sinus in five patients, a prolonged corrected sinus node recovery time in two patients, and the presence of a secondary pause in six patients. RESULTS: In patients with abnormal sinus node function a significant decrease was observed in the sinus node recovery time (-14% +/- 5%) and corrected sinus node recovery time (-33% +/- 25%) in response to aminophylline; however, neither parameter was normalized. A decrease in the sinus cycle length (-6% +/- 8%) was not statistically significant. In patients with normal sinus node function, a significant decrease was seen in both the sinus node recovery time (-9% +/- 7%) and sinus cycle length (-9% +/- 4%). The corrected sinus node recovery time decreased by 4% +/- 28% in patients with normal conditions but was not significant. Overall, aminophylline resolved the underlying sinus node abnormality in only one of thirteen patients with abnormal sinus node function. CONCLUSIONS: This study suggests that the use of theophylline in patients with marked sinus node dysfunction may not decrease their risks for subsequent bradycardic events.


Assuntos
Aminofilina/administração & dosagem , Arritmia Sinusal/tratamento farmacológico , Transplante de Coração , Nó Sinoatrial/efeitos dos fármacos , Adulto , Aminofilina/farmacologia , Arritmia Sinusal/complicações , Eletrofisiologia , Humanos , Infusões Intravenosas , Pessoa de Meia-Idade , Nó Sinoatrial/fisiopatologia
16.
J Heart Lung Transplant ; 22(11): 1234-44, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14585385

RESUMO

BACKGROUND: Hearts from non-heart-beating organ donors are not transplanted because of risk of ischemia-reperfusion injury. We tested whether pharmacologic pre-conditioning with adenosine and the Na(+)/H(+) exchanger inhibitor, cariporide, combined with controlled reperfusion, would prevent injury in porcine hearts that had sustained 30 minutes of hypoxia/ischemia in closed-chest animals. METHODS: Hearts from Yorkshire pigs (100 kg) were studied in 3 groups. Group 1 (control) hearts were surgically removed while beating. Group 2 hearts were harvested from animals made hypoxic by discontinuing mechanical ventilation for 30 minutes. Group 3 hearts were hypoxic as in Group 2, but these animals received adenosine (40 mg) and cariporide (400 mg) 10 minutes before stopping ventilation. Cardiac function in all groups was assessed ex vivo in a working heart apparatus in which pressure and flow measurements were made over 3 hours. Controlled reperfusion in Group 3 hearts used leukocyte-depleted blood perfusate containing free radical scavengers. Myocardial injury was assessed on the basis of perfusate creatine phosphokinase activity and histopathologically determined injury score. RESULTS: Groups 1 and 3 hearts could be resuscitated to perform work equivalently during the entire reperfusion period and showed positive responses to increases in pre-load and norepinephrine. Group 2 hearts could not perform work. After 3 hours, Group 2 hearts showed significantly higher creatine phosphokinase and histopathologic injury scores compared to with Groups 1 and 3, which were not significantly different from each other. CONCLUSIONS: Pharmacologic pre-conditioning and controlled reperfusion effectively protect non-beating porcine hearts from injury after 30 minutes of hypoxia/ischemia in situ.


Assuntos
Adenosina/uso terapêutico , Antiarrítmicos/uso terapêutico , Guanidinas/uso terapêutico , Precondicionamento Isquêmico Miocárdico/métodos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Sulfonas/uso terapêutico , Vasodilatadores/uso terapêutico , Animais , Creatina Quinase/metabolismo , Coração/efeitos dos fármacos , Coração/fisiopatologia , Hipóxia/metabolismo , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/enzimologia , Miocárdio/patologia , Suínos
17.
Surgery ; 97(6): 750-5, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3873716

RESUMO

Fibrin glue is used widely in Europe as a tissue sealant and hemostatic agent. The European glue is prepared commercially from pooled human blood. It is not available in this country because of the risk of transmission of hepatitis B, acquired immune deficiency syndrome, and other blood-transmitted diseases. We describe a cryoprecipitation technique for preparation of fibrin glue from single-donor fresh-frozen plasma. This technique enables the glue to be made in large quantities with no greater risk of disease transmission than with that from the transfusion of single-unit fresh-frozen plasma. We have found that the glue is a useful tool in surgery. By helping to control difficult bleeding, its use can decrease the need for blood transfusions and shorten operating room time. It also is effective as a means to pretreat highly porous vascular prostheses that currently are used infrequently because of bleeding. These porous grafts offer potential advantages in handling, suturing, and long-term patency. This new technique of fibrin glue preparation may make this useful surgical adjunct as readily available in this country as it is in Europe.


Assuntos
Fator XIII/isolamento & purificação , Fibrinogênio/isolamento & purificação , Trombina/isolamento & purificação , Adesivos Teciduais/isolamento & purificação , Precipitação Química , Crioprotetores , Combinação de Medicamentos/isolamento & purificação , Adesivo Tecidual de Fibrina , Congelamento , Humanos , Plasma
18.
Ann Thorac Surg ; 52(5): 1052-7, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1953123

RESUMO

Although the automatic implantable cardioverter defibrillator (AICD) is effective against malignant ventricular arrhythmias, the effects of AICD patches on left ventricular diastolic properties have not been defined. Accordingly, extrapericardial (group E, n = 5) or intrapericardial (group I, n = 6) AICD patches were implanted through a median sternotomy in 11 anesthetized pigs. Six weeks later, using a left thoracotomy, the hearts were arrested with hypothermic cardioplegia. A balloon catheter was inserted into the left ventricle through the aortic root, and pressure-volume curves were measured before and after sequential removal of patches and pericardium. A dense intrapericardial fibrotic reaction in group I was not present in group E. Normalized left ventricular filling volumes in group E were significantly larger at pressures of 5.1 to 10, 15.1 to 20, and 20.1 to 28 mm Hg compared with group I (p less than 0.05). We conclude that intrapericardial AICD patches adversely affect left ventricular diastolic pressure-volume relations and recommend that AICD patches be placed in the extrapericardial location clinically whenever possible.


Assuntos
Diástole/fisiologia , Cardioversão Elétrica/instrumentação , Próteses e Implantes , Função Ventricular Esquerda/fisiologia , Animais , Cateterismo Cardíaco , Eletrodos Implantados , Fibrose , Pericárdio/patologia , Próteses e Implantes/efeitos adversos , Suínos
19.
Ann Thorac Surg ; 62(3): 670-4, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8783991

RESUMO

BACKGROUND: Heart transplantation is associated with excessive bleeding due to recipient coagulopathy, frequent need for reoperative median sternotomy, and prolonged cardiopulmonary bypass. Aprotinin reduces bleeding and the inflammatory response after cardiopulmonary bypass, but there are concerns about efficacy and side effects. METHODS: To determine the role of aprotinin in primary and reoperative sternotomy heart transplantation, we studied 70 patients undergoing heart transplantation between August 1993 and October 1994. Thirty-eight undergoing primary sternotomy for heart transplantation and receiving no aprotinin were randomized to group A (n = 20); patients in group B (n = 18) received the full recommended dose. Similarly, 32 patients undergoing reoperative heart transplantation were randomized to group C (n = 16), receiving no aprotinin, and to group D (n = 16), receiving aprotinin at the full recommended dose. All patients received the same immunosuppression regimen. Similarities in the groups included recipient age, weight, preoperative hemodynamic indices, creatinine, creatinine clearance, platelet count, hemoglobin, percentage receiving warfarin, prothrombin time, partial thromboplastin time, cardiopulmonary bypass time, and creatinine level at 48 hours. RESULTS: There were no significant differences postoperatively between groups A and B. Differences (p < 0.05) 24 hours postoperatively between groups C and D, respectively, included: total blood product requirement (5.9 +/- 3.8 versus 3.6 +/- 2.0 U), total fluid balance (+752 +/- 300 versus -250 +/- 185 mL), chest tube drainage (894 +/- 120 versus 526 +/- 95 mL), alveolar-arterial O2 difference (120.4 +/- 45.9 versus 95.5 +/- 33.5), and pulmonary artery mean pressures (28.2 +/- 4.6 versus 21.1 +/- 3.5 mm Hg). CONCLUSIONS: Aprotinin decreases bleeding after reoperative heart transplantation without renal dysfunction. Decreased inflammation is manifested as reduced fluid requirement and improved pulmonary and right heart function, which benefit patients during the posttransplantation period. Aprotinin at recommended doses is effective and safe for patients undergoing reoperative heart transplantation.


Assuntos
Aprotinina/uso terapêutico , Transplante de Coração , Hemostáticos/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue , Ponte Cardiopulmonar , Tubos Torácicos , Drenagem , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reoperação , Esterno/cirurgia
20.
Ann Thorac Surg ; 62(5): 1268-75, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8893556

RESUMO

BACKGROUND: The lack of satisfactory donor organs limits heart transplantation. The purpose of this study was to determine whether the criteria for suitability of donors may be safely expanded. METHODS: One hundred ninety-six heart transplantations were performed on 192 patients at our institution from January 1992 to 1995 and were divided into two groups. Group A donors (n = 113) conformed to the standard criteria. Group B donors (n = 83) deviated by at least one factor and consisted of the following: 16 hearts from donors greater than 50 years of age, 33 with myocardial dysfunction (echocardiographic ejection fraction = 0.35 +/- 0.10, dopamine level exceeding 20 micrograms.kg-1.min-1, and resuscitation with triiodothyronine), 33 undersized donors with donor to recipient weight ratios of 0.45 +/- 0.04, 48 with extended ischemic times of 297.4 +/- 53.6 minutes, 25 with positive blood cultures, 16 with positive hepatitis C antibody titers, and 7 with conduction abnormalities (Wolff-Parkinson-White syndrome, prolonged QT interval, bifascicular block). RESULTS: Thirty-day mortality was 6.2% (7/113) in group A and 6.0% (5/83) in group B. Mortality in group A was attributed to 3 patients with myocardial dysfunction, 2 with infection, 1 with acute rejection, and 1 with pancreatitis; group B had 2 with myocardial dysfunction, 1 with infection, 1 with aspiration, and 1 with bowel infarction. At 12 months, survival and hemodynamic indices were similar between the groups. Of the 16 recipients with hepatitis C-positive hearts, 5 have become hepatitis C positive with mild hepatitis (follow up, 6 to 30 months). CONCLUSIONS: Expanding the criteria for suitability of donor hearts dramatically increases the number of transplantations without compromising recipient outcome.


Assuntos
Transplante de Coração , Seleção de Pacientes , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/normas , Adulto , Fatores Etários , Idoso , Constituição Corporal , Feminino , Transplante de Coração/efeitos adversos , Transplante de Coração/mortalidade , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Obtenção de Tecidos e Órgãos/métodos , Resultado do Tratamento
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