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1.
Am Heart J ; 261: 64-74, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36966922

RESUMO

BACKGROUND: Artificial intelligence (AI), and more specifically deep learning, models have demonstrated the potential to augment physician diagnostic capabilities and improve cardiovascular health if incorporated into routine clinical practice. However, many of these tools are yet to be evaluated prospectively in the setting of a rigorous clinical trial-a critical step prior to implementing broadly in routine clinical practice. OBJECTIVES: To describe the rationale and design of a proposed clinical trial aimed at evaluating an AI-enabled electrocardiogram (AI-ECG) for cardiomyopathy detection in an obstetric population in Nigeria. DESIGN: The protocol will enroll 1,000 pregnant and postpartum women who reside in Nigeria in a prospective randomized clinical trial. Nigeria has the highest reported incidence of peripartum cardiomyopathy worldwide. Women aged 18 and older, seen for routine obstetric care at 6 sites (2 Northern and 4 Southern) in Nigeria will be included. Participants will be randomized to the study intervention or control arm in a 1:1 fashion. This study aims to enroll participants representative of the general obstetric population at each site. The primary outcome is a new diagnosis of cardiomyopathy, defined as left ventricular ejection fraction (LVEF) < 50% during pregnancy or within 12 months postpartum. Secondary outcomes will include the detection of impaired left ventricular function (at different LVEF cut-offs), and exploratory outcomes will include the effectiveness of AI-ECG tools for cardiomyopathy detection, new diagnosis of cardiovascular disease, and the development of composite adverse maternal cardiovascular outcomes. SUMMARY: This clinical trial focuses on the emerging field of cardio-obstetrics and will serve as foundational data for the use of AI-ECG tools in an obstetric population in Nigeria. This study will gather essential data regarding the utility of the AI-ECG for cardiomyopathy detection in a predominantly Black population of women and pave the way for clinical implementation of these models in routine practice. TRIAL REGISTRATION: Clinicaltrials.gov: NCT05438576.


Assuntos
Cardiomiopatias , Transtornos Puerperais , Gravidez , Humanos , Feminino , Função Ventricular Esquerda , Volume Sistólico , Inteligência Artificial , Nigéria/epidemiologia , Período Periparto , Estudos Prospectivos , Cardiomiopatias/diagnóstico , Cardiomiopatias/epidemiologia , Cardiomiopatias/etiologia , Transtornos Puerperais/diagnóstico , Transtornos Puerperais/epidemiologia
2.
iScience ; 26(12): 108493, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38146431

RESUMO

Myocarditis is typically caused by viral infections, but most cases are thought to be subclinical. Echocardiography is often used for initial assessment of myocarditis patients but is poor at detecting subtle changes in cardiac dysfunction. Cardiac strain, such as global longitudinal strain (GLS) and global circumferential strain (GCS), represents an increasingly used set of measurements which can detect these subtle changes. Using a murine model of coxsackievirus B3 myocarditis, we characterized functional changes in the heart using echocardiography during myocarditis and by sex. We found that 2D GLS, 4D mode, and 4D strains detected a significant reduction in ejection fraction and GLS during myocarditis compared to baseline and in males compared to females. Furthermore, worse GLS correlated to increased levels of CD45+, CD11b+, and CD3+ immune cells. Our findings closely resemble published reports of GLS in patients with myocarditis indicating the usefulness of this animal model for translational studies of myocarditis.

3.
Mayo Clin Proc ; 98(1): 31-47, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36603956

RESUMO

OBJECTIVE: To compare clinical characteristics, treatment patterns, and 30-day all-cause readmission and mortality between patients hospitalized for heart failure (HF) before and during the coronavirus disease 2019 (COVID-19) pandemic. PATIENTS AND METHODS: The study was conducted at 16 hospitals across 3 geographically dispersed US states. The study included 6769 adults (mean age, 74 years; 56% [5033 of 8989] men) with cumulative 8989 HF hospitalizations: 2341 hospitalizations during the COVID-19 pandemic (March 1 through October 30, 2020) and 6648 in the pre-COVID-19 (October 1, 2018, through February 28, 2020) comparator group. We used Poisson regression, Kaplan-Meier estimates, multivariable logistic, and Cox regression analysis to determine whether prespecified study outcomes varied by time frames. RESULTS: The adjusted 30-day readmission rate decreased from 13.1% (872 of 6648) in the pre-COVID-19 period to 10.0% (234 of 2341) in the COVID-19 pandemic period (relative risk reduction, 23%; hazard ratio, 0.77; 95% CI, 0.66 to 0.89). Conversely, all-cause mortality increased from 9.7% (645 of 6648) in the pre-COVID-19 period to 11.3% (264 of 2341) in the COVID-19 pandemic period (relative risk increase, 16%; number of admissions needed for one additional death, 62.5; hazard ratio, 1.19; 95% CI, 1.02 to 1.39). Despite significant differences in rates of index hospitalization, readmission, and mortality across the study time frames, the disease severity, HF subtypes, and treatment patterns remained unchanged (P>0.05). CONCLUSION: The findings of this large tristate multicenter cohort study of HF hospitalizations suggest lower rates of index hospitalizations and 30-day readmissions but higher incidence of 30-day mortality with broadly similar use of HF medication, surgical interventions, and devices during the COVID-19 pandemic compared with the pre-COVID-19 time frame.


Assuntos
COVID-19 , Insuficiência Cardíaca , Masculino , Adulto , Humanos , Idoso , Pandemias , Estudos de Coortes , COVID-19/epidemiologia , COVID-19/terapia , Hospitalização , Readmissão do Paciente , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia
4.
J Clin Med ; 11(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35956137

RESUMO

COVID-19 mRNA vaccinations have recently been implicated in causing myocarditis. Therefore, the primary aim of this systematic review and meta-analysis was to investigate the clinical characteristics of patients with myocarditis following mRNA vaccination. The secondary aims were to report common imaging and laboratory findings, as well as treatment regimes, in these patients. A literature search was performed from December 2019 to June 2022. Eligible studies reported patients older than 18 years vaccinated with mRNA, a diagnosis of myocarditis, and subsequent outcomes. Pooled mean or proportion were analyzed using a random-effects model. Seventy-five unique studies (patient n = 188, 89.4% male, mean age 18-67 years) were included. Eighty-six patients had Moderna vaccines while one hundred and two patients had Pfizer-BioNTech vaccines. The most common presenting symptoms were chest pain (34.5%), fever (17.1%), myalgia (12.4%), and chills (12.1%). The most common radiologic findings were ST-related changes on an electrocardiogram (58.7%) and hypokinesia on cardiac magnetic resonance imaging or echocardiography (50.7%). Laboratory findings included elevated Troponin I levels (81.7%) and elevated C-reactive protein (71.5%). Seven patients were admitted to the intensive care unit. The most common treatment modality was non-steroid anti-inflammatory drugs (36.6%) followed by colchicine (28.5%). This meta-analysis presents novel evidence to suggest possible myocarditis post mRNA vaccination in certain individuals, especially young male patients. Clinical practice must therefore take appropriate pre-cautionary measures when administrating COVID-19 mRNA vaccinations.

5.
J Clin Med ; 11(12)2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35743613

RESUMO

As survival in breast cancer patients from newer therapies increases, concerns for chemotherapy-induced cardiotoxicity (CIC) have offset some of these benefits, manifesting as a decline in left ventricular ejection fraction (LVEF). Patients receiving anthracycline-based chemotherapy followed by trastuzumab are at risk for CIC. Previous research evaluating whether clinical biomarkers predict cardiotoxicity has been inconsistent. Recently, angiotensin II type 1 receptor (ATR1) and endothelin 1 (ET1) have been shown to play a role in breast tumor growth. We evaluated ATR1 and ET1 expression in breast cancer tissue and its association with CIC. A total of 33 paraffin-embedded breast tissue specimens from women with breast cancer treated with anthracycline-based chemotherapy and trastuzumab were analyzed by immunohistochemistry (IHC) and qRT-PCR. We found that ET1 expression was increased in patients with an LVEF ≤ 50% (p = 0.032) with a lower LVEF correlating with higher ET1 expression (r = 0.377, p = 0.031). In patients with a change in LVEF of greater than 10%, greater ET1 expression was noted compared to those without a change in LVEF (p = 0.017). Increased ET1 expression in breast tumor tissue is associated with reduced LVEF. Future studies need to examine whether ET1 may be a tissue biomarker that helps predict the risk of developing CIC in women with breast cancer.

6.
Eur Heart J Digit Health ; 2(4): 586-596, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34993486

RESUMO

AIMS: Cardiovascular disease is a major threat to maternal health, with cardiomyopathy being among the most common acquired cardiovascular diseases during pregnancy and the postpartum period. The aim of our study was to evaluate the effectiveness of an electrocardiogram (ECG)-based deep learning model in identifying cardiomyopathy during pregnancy and the postpartum period. METHODS AND RESULTS: We used an ECG-based deep learning model to detect cardiomyopathy in a cohort of women who were pregnant or in the postpartum period seen at Mayo Clinic. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, and specificity. We compared the diagnostic probabilities of the deep learning model with natriuretic peptides and a multivariable model consisting of demographic and clinical parameters. The study cohort included 1807 women; 7%, 10%, and 13% had left ventricular ejection fraction (LVEF) of 35% or less, <45%, and <50%, respectively. The ECG-based deep learning model identified cardiomyopathy with AUCs of 0.92 (LVEF ≤ 35%), 0.89 (LVEF < 45%), and 0.87 (LVEF < 50%). For LVEF of 35% or less, AUC was higher in Black (0.95) and Hispanic (0.98) women compared to White (0.91). Natriuretic peptides and the multivariable model had AUCs of 0.85 to 0.86 and 0.72, respectively. CONCLUSIONS: An ECG-based deep learning model effectively identifies cardiomyopathy during pregnancy and the postpartum period and outperforms natriuretic peptides and traditional clinical parameters with the potential to become a powerful initial screening tool for cardiomyopathy in the obstetric care setting.

7.
Clin Transplant ; 22(1): 76-81, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18251036

RESUMO

BACKGROUND: Chronic use of corticosteroids (CS) following transplantation is associated with significant long-term morbidities. Minimizing exposure to CS to improve long-term outcomes, without compromising allograft function, remains an important goal in transplantation. OBJECTIVES: This single-center, prospective, randomized, open-label study was designed to evaluate the efficacy of Thymoglobulin as part of a CS-sparing regimen in cardiac transplantation. METHODS: Thirty-two low-risk cardiac transplant patients were randomized in a 1:1 ratio to receive either a Thymoglobulin-based CS-avoidance regimen (CS-avoidance group; n = 16) or a long-term CS-based regimen with no antibody induction (control group; n = 16). Pulse CS therapy was used for the treatment of acute cellular rejection in both groups. RESULTS: Baseline characteristics were similar between groups. At one yr, there was no significant difference in the mean incidence of acute cellular rejection (>or=3A) episodes between the CS-avoidance and control groups, 0.81+/-1.05 and 1.07+/-1.03, respectively. Importantly, the CS-avoidance patients had significant improvement in muscle strength and less bone loss compared with the control patients during the first six months post-transplant. CONCLUSIONS: CS-avoidance regimen with Thymoglobulin induction appeared to be safe and effective in cardiac transplantation. Further studies are required to demonstrate the long-term safety and benefits of such a regimen.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Transplante de Coração , Adulto , Antibioticoprofilaxia , Soro Antilinfocitário , Densidade Óssea/efeitos dos fármacos , Feminino , Glucocorticoides/administração & dosagem , Rejeição de Enxerto/tratamento farmacológico , Transplante de Coração/imunologia , Transplante de Coração/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Estudos Prospectivos , Pulsoterapia , Tacrolimo/administração & dosagem , Transplante Homólogo
8.
Congest Heart Fail ; 14(4): 192-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18772624

RESUMO

The authors prospectively investigated whether left bundle branch block (LBBB) and myocardial degradation as indicated by elevated troponin T (tnT) predict the phenomenon of systolic conversion to low ejection fraction (EF 40%). Thirty consecutive patients with HFPSF were included and followed over a 4-year interval. A follow-up EF assessment was performed in 25 patients. Six of 15 patients with tnT >or=0.01 ng/mL demonstrated systolic conversion to low EF on follow-up, while none of the 10 patients with tnT <0.01 ng/mL experienced this phenomenon (P=.03). Five of the 6 converters presented with LBBB, while only 1 of the 19 nonconverters had this abnormality (P=.0007). Four of the 6 converters had an initial EF >50%. Myocardial degradation and LBBB predicted systolic conversion in HFPSF patients with nonsignificant coronary disease.


Assuntos
Bloqueio de Ramo/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Miocárdio/patologia , Idoso , Idoso de 80 Anos ou mais , Bloqueio de Ramo/diagnóstico , Progressão da Doença , Feminino , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Volume Sistólico , Sístole
9.
Curr Opin Organ Transplant ; 13(6): 581-5, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19060546

RESUMO

PURPOSE OF REVIEW: Hypogammaglobulinemia may develop as a result of a number of immune deficiency syndromes that can be devastating. This review article explores the risk of infection associated with hypogammaglobulinemia in solid organ transplantation and discusses therapeutic strategies to alleviate such a risk. RECENT FINDINGS: Hypogammaglobulinemia is associated with increased risk of opportunistic infections, particularly during the 6-month posttransplant period when viral infections are most prevalent. The preemptive use of immunoglobulin replacement results in a significant reduction of opportunistic infections in patients with moderate and severe hypogammaglobulinemia. SUMMARY: Monitoring immunoglobulin G levels may aid in clinical management of solid organ transplant recipients. The preemptive use of immunoglobulin replacement may serve as a new strategy for managing solid organ transplant recipients with hypogammaglobulinemia.


Assuntos
Agamaglobulinemia/etiologia , Doenças Transmissíveis/etiologia , Infecções Oportunistas/etiologia , Transplante de Órgãos/efeitos adversos , Agamaglobulinemia/sangue , Agamaglobulinemia/tratamento farmacológico , Animais , Doenças Transmissíveis/tratamento farmacológico , Transplante de Coração/efeitos adversos , Humanos , Imunoglobulina G/sangue , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Transplante de Rim/efeitos adversos , Transplante de Fígado/efeitos adversos , Transplante de Pulmão/efeitos adversos , Infecções Oportunistas/prevenção & controle , Medição de Risco
10.
Cleve Clin J Med ; 74 Suppl 1: S110-3, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17455557

RESUMO

The human heart transplant model unmasks the heart-brain link as an active process that is clinically demonstrated and confirmed at the tissue level. Further studies are needed to elucidate the relative contribution of each of these isolated observations to the pathogenesis of coronary allograft vasculopathy, which remains enigmatic. Recent studies have suggested that mTOR inhibitors may have the ability to attenuate this lethal process that limits the long-term survival of cardiac transplant recipients. The observations we have discussed here suggest that other targeted therapies, including glycoprotein IIb/IIIa inhibitors, tissue metalloproteinase inhibitors, and angiotensin receptor blockers, may facilitate the attenuation of cardiac transplant vasculopathy, but clinical trials are difficult to conduct in this relatively small population of patients. These observations may shed insight, however, into the pathophysiology of hypertension and its impact on the vascular system, as cardiac transplantation provides a setting in which heart-brain interactions are magnified and the pathophysiology occurs over years rather than decades.


Assuntos
Encefalopatias/complicações , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/cirurgia , Transplante de Coração , Encefalopatias/fisiopatologia , Seleção do Doador , Insuficiência Cardíaca/fisiopatologia , Humanos , Modelos Cardiovasculares
11.
Circulation ; 105(16): 1955-61, 2002 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-11997283

RESUMO

BACKGROUND: Myocardial ischemic injury after heart transplantation is associated with subsequent development of graft vasculopathy. Both vitronectin receptor (integrin alpha(v)beta3) and tissue factor play key roles in vascular endothelial cell injury. Matrix metalloproteinases (MMPs) are activated in ischemic injury models. METHODS AND RESULTS: Thirteen patients developed myocardial ischemic injury within 2 weeks of cardiac transplantation (ischemia group). These were compared with 10 transplantation patients who had no evidence of ischemia (control group). Endomyocardial biopsies were evaluated within 2 weeks of transplantation for alpha(v)beta3, tissue factor, and extracellular MMP inducer (EMMPRIN). At 1 year, MMPs were evaluated, and interstitial myocardial fibrosis was quantified. All patients underwent intravascular ultrasound at 1 month and 1 year after transplantation. Compared with control, the ischemia group demonstrated evidence of significant increased expression of alpha(v)beta3 (3.2-fold, P<0.001), tissue factor (2.5-fold, P<0.001), and EMMPRIN (1.9-fold, P=0.01). At 1 year, the ischemia group had a significant increase in myocardial fibrosis (24+/-1.8% versus 14+/-1.1%, P<0.001) and zymographic activity of MMP-2 (1.4-fold, P<0.001), MMP-3 (1.2-fold, P<0.001), and MMP-9 (1.3-fold, P=0.01). Coronary vasculopathy progression was also more advanced in the ischemia group (change in coronary maximal intimal thickness over 1 year 0.54+/-0.1 versus 0.26+/-0.06 mm; P=0.031). CONCLUSIONS: Myocardial ischemic injury after cardiac transplantation is associated with upregulation of alpha(v)beta3, tissue factor, and activation of the MMP induction system, which may contribute to the subsequent development of allograft remodeling and vasculopathy.


Assuntos
Transplante de Coração/efeitos adversos , Metaloproteinases da Matriz/metabolismo , Isquemia Miocárdica/metabolismo , Receptores de Vitronectina/biossíntese , Adulto , Progressão da Doença , Ativação Enzimática , Ensaio de Imunoadsorção Enzimática , Feminino , Fibrose , Humanos , Immunoblotting , Imuno-Histoquímica , Masculino , Metaloproteinases da Matriz/imunologia , Pessoa de Meia-Idade , Modelos Cardiovasculares , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/patologia , Receptores de Vitronectina/imunologia , Tromboplastina/biossíntese , Tromboplastina/imunologia , Ultrassonografia , Regulação para Cima
12.
Circulation ; 108(14): 1724-8, 2003 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-12975253

RESUMO

BACKGROUND: Matrix metalloproteinase (MMP)-2 and MMP-9 have been shown to play a role in the progression of hemorrhagic stroke. We hypothesized that donor intracerebral hemorrhage (ICH) is associated with activation of the metalloproteinases before transplantation that play a key role in the subsequent development of transplant vasculopathy. METHODS AND RESULTS: We evaluated mRNA expressions of MMP-2 and MMP-9 in donor spleen lymphocytes (before transplantation) and in heart biopsies at 1 week after transplantation in 20 recipients from ICH donors and 20 recipients from trauma donors. Patients underwent serial coronary intravascular ultrasound, and interstitial myocardial fibrosis was quantified at 1 year. The baseline characteristics were similar except for increased donor age in the ICH group. Heart biopsies from the ICH group showed significant increased expression of MMP-2 (17-fold, P<0.0001) and MMP-9 (20-fold, P<0.0001) compared with the trauma group. Furthermore, the ICH group showed 1.8-fold (P=0.016) increased mRNA expression of MMP-2 and 1.7-fold (P=0.015) increased mRNA expression of MMP-9 in the donor spleen lymphocytes, suggesting the presence of systemic activation of metalloproteinases before transplantation. At 1 year, the ICH group showed increased myocardial fibrosis and accelerated coronary vasculopathy. Using multivariate regression analysis, MMP-9 was found to be associated with increased risk for vasculopathy independent of donor age (OR, 2.41; P=0.01; 95% CI, 1.24 to 4.69). CONCLUSIONS: This is the first report to describe systemic activation of MMP-2 and MMP-9 in donors with intracerebral hemorrhage and subsequent development of allograft vasculopathy.


Assuntos
Hemorragia Cerebral/complicações , Doença das Coronárias/etiologia , Transplante de Coração , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Doadores de Tecidos , Adulto , Hemorragia Cerebral/enzimologia , Hemorragia Cerebral/genética , Doença das Coronárias/enzimologia , Doença das Coronárias/patologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Ativação Enzimática , Feminino , Humanos , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Ultrassonografia
13.
Circulation ; 105(15): 1768-71, 2002 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-11956116

RESUMO

BACKGROUND: Endothelin-1 (ET-1), a potent vasoconstrictor, is released in response to several inflammatory cytokines after heart transplantation. The present study correlated patterns of myocardial ET-1 expression in heart biopsies with acute rejection, post-transplantation ischemic injury, and subsequent development of coronary vasculopathy. METHODS AND RESULTS: Patterns of myocardial ET-1 expression were evaluated in 47 heart transplant recipients at 3 months after transplant. Transplant vasculopathy was documented by coronary angiography at 2 years after transplant. Expression of ET-1 was tabulated for both blood vessels and the interstitium. Vascular ET-1 expression was positive in 7/17 (41%) of patients with greater than grade 2 (International Society Heart Lung Transplant) rejection compared with 3/30 (10%) of patients with grade 0 and grade 1A rejection (P=0.02). Compared with patients with negative interstitial ET-1 expression (n=22), patients with positive interstitial ET-1 expression (n=25) had higher incidence of post-transplantation ischemic injury (52% versus 9%, P=0.002), lower mean episodes of acute rejection (> or = grade 2) during the first 3 months of transplant (1.09+/-0.66 versus 1.86+/-1.6, P=0.048), and more common vasculopathy at 2 years (50% versus 15%, P=0.02), and they tended to have worse survival (83.2% versus 100%, P=0.058). CONCLUSIONS: Vascular ET-1 expression is likely to be associated with acute rejection. Interstitial ET-1 expression, however, is more likely to be associated with post-transplantation ischemic injury and subsequent development of coronary vasculopathy.


Assuntos
Endotelina-1/metabolismo , Transplante de Coração , Miocárdio/metabolismo , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/etiologia , Doença das Coronárias/metabolismo , Vasos Coronários/metabolismo , Rejeição de Enxerto/metabolismo , Transplante de Coração/efeitos adversos , Transplante de Coração/diagnóstico por imagem , Transplante de Coração/mortalidade , Humanos , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/metabolismo , Taxa de Sobrevida , Resultado do Tratamento
14.
J Am Coll Cardiol ; 43(9): 1565-73, 2004 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-15120813

RESUMO

OBJECTIVES: We evaluated whether the angiotensin II (Ang II) receptors from perioperation through one-year post-transplantation predict the transplant coronary artery disease (TCAD) progression. BACKGROUND: The role of Ang II receptors (type 1: AT(1)R; type 2: AT(2)R) in TCAD is uncertain. METHODS: We investigated 28 heart donors and the corresponding recipients. The levels of AT(1)R and AT(2)R messenger ribonucleic acid (mRNA) were examined in lymphocytes from the donor spleen and in the donor heart at one-week and one-year posttransplantation to determine their association with the progression of TCAD, measured as changes in maximal intimal thickness (CMIT) and plaque volume (CPV) by intravascular ultrasound (IVUS) examinations. RESULTS: The AT(1)R mRNA in lymphocytes from the donor spleen (CMIT: r = 0.73, p < 0.0001; CPV: r = 0.69, p < 0.0001) and in the donor hearts at one-week (CMIT: r = 0.52, p = 0.005; CPV: r = 0.56, p = 0.002) and at one-year (CMIT: r = 0.63, p < 0.0001; CPV: r = 0.43, p = 0.004) post-transplantation along with AT(2)R mRNA in the donor hearts at one-year post-transplantation (CMIT: r = 0.3, p < 0.0001; CPV: r = 0.53, p = 0.009) were univariate predictors, whereas AT(1)R mRNA in lymphocytes and in the donor hearts at one-year post-transplantation proved to be multivariate predictors of the progression of TCAD. CONCLUSIONS: These data suggest a role for Ang II receptors in the pathogenesis of TCAD and support a novel concept that TCAD may have its origin in the donor per se and may be modulated by the recipient's inherent biological factors.


Assuntos
Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Transplante de Coração , Receptores de Angiotensina/biossíntese , Adulto , Idoso , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Biópsia , Doença da Artéria Coronariana/metabolismo , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/metabolismo , Vasos Coronários/patologia , Progressão da Doença , Feminino , Imunofluorescência , Seguimentos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/cirurgia , Humanos , Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/metabolismo , Valor Preditivo dos Testes , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Angiotensina/biossíntese , Fatores de Risco , Doadores de Tecidos , Resultado do Tratamento , Túnica Íntima/diagnóstico por imagem , Túnica Íntima/metabolismo , Túnica Íntima/patologia , Ultrassonografia de Intervenção
15.
J Am Coll Cardiol ; 39(5): 804-10, 2002 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-11869845

RESUMO

OBJECTIVES: This study was undertaken to test the hypothesis that transplant coronary vasculopathy (CV) is associated with increased myocardial protein expression of both tissue factor (TF) and integrin alphavbeta3. BACKGROUND: The vitronectin receptor (integrin alphavbeta3) and TF have recently been found to play a key role in apoptotic cell death and vascular endothelial cell injury. METHODS: A total of 77 heart transplant recipients underwent simultaneous endomyocardial biopsy and intravascular ultrasound (IVUS) at one year of transplant. Patients with pre-existing donor coronary atherosclerosis (n = 35) or with acute rejection (grade >1A, n = 10) at the time of the IVUS were excluded from the analysis. The remaining 32 patients constitute the cohort of the present study. A computerized biopsy score was derived based on the duration and severity of cellular rejection. Both TF and alphavbeta3 expression in the heart biopsy specimens were evaluated by immunoperoxidase histochemistry and Western blot analysis. RESULTS: Patients with CV (n = 24) had increased expression of alphavbeta3 (2.7-fold, p = 0.003) and TF (7.9-fold, p = 0.04) compared with patients without evidence of vasculopathy (n = 8). In the absence of myocardial fibrosis, alphavbeta3 expression correlated significantly with the cellular rejection score (r = 0.58, p = 0.02). CONCLUSIONS: Transplant vasculopathy is associated with increased expression of both TF and alphavbeta3. The significant correlation of alphavbeta3 with cellular rejection suggests an important role for this integrin in serving as a mechanistic link between cellular rejection and vasculopathy.


Assuntos
Doenças Cardiovasculares/fisiopatologia , Transplante de Coração/fisiologia , Receptores de Vitronectina/fisiologia , Tromboplastina/fisiologia , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/patologia , Estudos de Coortes , Feminino , Seguimentos , Rejeição de Enxerto/diagnóstico por imagem , Rejeição de Enxerto/patologia , Rejeição de Enxerto/fisiopatologia , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Índice de Gravidade de Doença , Fatores de Tempo , Ultrassonografia de Intervenção , Regulação para Cima/fisiologia
16.
J Am Coll Cardiol ; 39(6): 970-7, 2002 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-11897438

RESUMO

OBJECTIVES: We sought to assess the influence of peritransplant ischemia and fibrosis on the development of allograft vasculopathy, acute cellular rejection and long-term outcome. BACKGROUND: Allograft vasculopathy is a common long-term complication of cardiac transplantation. One of the potential risk factors is peritransplant allograft ischemia. METHODS: One hundred forty heart transplant recipients had baseline and one-year intravascular ultrasound analysis done to assess the progression of allograft vasculopathy. Serial endomyocardial biopsies were evaluated for cellular rejection, vascular rejection, ischemia and fibrosis. Based on histology, patients were classified into one of the following groups: nonischemic (n = 32), ischemia (n = 24), fibrosis (n = 62) or vascular rejection (n = 22). Three-color flow cytometry crossmatching (FCXM) was used to assess donor-specific human lymphocyte antigens (HLA) sensitization. Long-term outcome of patients in each group was assessed by estimating incidence of graft failure or deaths over a seven-year follow up. RESULTS: Patients in the fibrosis group had the lowest incidence of donor-specific HLA sensitization (40%, p = 0.008) and lowest average episodes of cellular rejection (1.7 +/- 1.4, p = 0.04), but they had increased coronary vasculopathy progression (change in coronary intimal thickness = 0.59 +/- 0.28 mm, p < 0.0001) and poor seven-year event-free survival (49%, p = 0.01). CONCLUSIONS: The development of fibrosis after cardiac transplantation is associated with advanced coronary vasculopathy, although a low incidence of acute cellular rejection is noted, suggesting the presence of nonimmune mechanisms in mediating the pathogenesis of allograft vasculopathy.


Assuntos
Fibrose Endomiocárdica/etiologia , Fibrose Endomiocárdica/mortalidade , Transplante de Coração/mortalidade , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/mortalidade , Adolescente , Adulto , Angiografia Coronária , Progressão da Doença , Fibrose Endomiocárdica/diagnóstico por imagem , Seguimentos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/mortalidade , Sobrevivência de Enxerto/imunologia , Antígenos HLA/imunologia , Transplante de Coração/imunologia , Humanos , Incidência , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Ohio/epidemiologia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Estudos Prospectivos , Análise de Sobrevida , Tempo , Doadores de Tecidos , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/mortalidade
17.
J Heart Lung Transplant ; 24(8): 1014-8, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16102435

RESUMO

BACKGROUND: Recipients of hearts from donors with spontaneous intracerebral hemorrhage (ICH) are at increased risk of allograft vasculopathy compared with trauma donors. We have recently shown that the vitronectin receptor (integrin alpha(V)beta3) is upregulated in transplant vasculopathy. We hypothesized that donor ICH is associated with systemic activation of alpha(V)beta3 in the donor before transplantation. METHODS: We evaluated mRNA expressions of alpha(V)beta3 (TaqMan PCR) in endomyocardial biopsy samples at 1-week post-transplant in 20 recipients from ICH donors and 20 recipients from trauma donors. To investigate whether systemic activation of alpha(V)beta3 was present in the donor before transplantation, alpha(V)beta3 expression was also evaluated in the corresponding donor spleen lymphocytes. All patients underwent serial coronary intravascular ultrasound to evaluate for coronary vasculopathy. The baseline characteristics were similar except for increased donor age in the ICH Group. RESULTS: The ICH Group showed significant increased mRNA expression of alpha(V)beta3 in the heart biopsy samples (3.8-fold, p = 0.012) and in the corresponding donor spleen lymphocytes (3.5-fold, p = 0.014) compared with the Trauma Group. At 1 year, the ICH Group also showed increased progression of coronary vasculopathy. Multivariate regression analysis found that donor lymphocytic alpha(V)beta3 mRNA expression was independently associated with increased risk of vasculopathy (odds ratio, 1.9; 95% CI, 1.21-3.98, p = 0.03). CONCLUSIONS: Our report demonstrates the presence of systemic activation of alpha(V)beta3 in donors with spontaneous intracerebral hemorrhage and its association with the subsequent development of allograft vasculopathy in the recipient.


Assuntos
Hemorragia Cerebral/complicações , Endocárdio/patologia , Transplante de Coração/efeitos adversos , Integrina alfaVbeta3/metabolismo , Doadores de Tecidos , Doenças Vasculares/etiologia , Sequência de Bases , Biópsia por Agulha , Estudos de Casos e Controles , Hemorragia Cerebral/diagnóstico , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Transplante de Coração/métodos , Humanos , Imuno-Histoquímica , Integrina alfaVbeta3/análise , Masculino , Dados de Sequência Molecular , Análise Multivariada , Cuidados Pré-Operatórios , Prevalência , Probabilidade , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medição de Risco , Estatísticas não Paramétricas , Transplante Homólogo , Ultrassonografia de Intervenção , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/epidemiologia
18.
J Heart Lung Transplant ; 24(8): 1033-8, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16102438

RESUMO

BACKGROUND: Hypertension is a potential risk factor for allograft coronary vasculopathy. We evaluated the efficacy of angiotensin-converting enzyme (ACE) inhibitors and calcium antagonists, and their combined use, on the development of coronary vasculopathy in hypertensive heart transplant recipients. METHODS: Eighty-two heart transplant recipients underwent serial intravascular ultrasound (IVUS) analysis at baseline (within 1 month) and at 1 year after transplantation and were evaluated for the development of coronary vasculopathy. Patients were divided into 4 groups. Nineteen normotensive recipients received no treatment, control (Group A). Hypertensive patients were treated with either ACE inhibitors (Group B, n = 37), calcium antagonists (Group C, n = 16), or both (Group D, n = 10). RESULTS: We found a significant reduction in IVUS indices of coronary vasculopathy in heart transplant recipients who used a combination of an ACE inhibitor and a calcium antagonist compared with recipients who used either drug alone (p < 0.05). This synergistic efficacy was independent of the baseline indices evaluated in a multivariate regression analysis model and was noted despite comparable mean arterial pressure among the 3 hypertensive groups at 1 year, thus suggesting the presence of a synergistic anti-proliferative effect beyond the anti-hypertensive efficacy. CONCLUSIONS: The combined use of an ACE inhibitor and a calcium antagonist is more effective than the individual use of either drug alone on the development of coronary vasculopathy in cardiac transplant recipients. Large randomized clinical trials are warranted to evaluate such a synergistic efficacy.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Bloqueadores dos Canais de Cálcio/administração & dosagem , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/tratamento farmacológico , Transplante de Coração/efeitos adversos , Ultrassonografia de Intervenção , Idoso , Estudos de Casos e Controles , Doença das Coronárias/fisiopatologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Rejeição de Enxerto , Sobrevivência de Enxerto , Transplante de Coração/métodos , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/tratamento farmacológico , Probabilidade , Valores de Referência , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Taxa de Sobrevida , Resultado do Tratamento
19.
Transplantation ; 75(1): 72-8, 2003 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-12544874

RESUMO

BACKGROUND: Factors directing T-cell infiltration into allografts during acute rejection remain poorly defined. Chemokines have been shown to mediate leukocyte recruitment into allografts in animal models of rejection. The goal of this study was to test the presence and levels of chemokine and receptor gene expression in serial endomyocardial biopsy specimens from heart transplant patients and to correlate the levels observed with histopathologic rejection grade. METHODS: Three hundred sixteen serial endomyocardial biopsy specimens from 30 heart transplant patients were obtained during the clinically scheduled surveillance heart biopsy program. The follow-up period was 1 year. The expression of interferon (IFN)-gamma inducible protein (IP)-10, monokine induced by IFN-gamma (Mig), interferon-inducible T-cell alpha chemoattractant (I-TAC), regulated on activation normal T-cell expressed and secreted (RANTES), monocyte chemotactic protein (MCP)-1, interleukin (IL)-8, and the receptors CXCR3 and CCR5 were tested using quantitative, real-time polymerase chain reaction. Biopsy samples were examined histologically to assign rejection grade. RESULTS: Expression of IP-10, Mig, I-TAC, RANTES, CXCR3, and CCR5, but not MCP-1 and IL-8, increased significantly in both grade 2 and grade 3 rejection (P

Assuntos
Quimiocinas/genética , Expressão Gênica , Rejeição de Enxerto , Transplante de Coração/imunologia , Receptores de Quimiocinas/genética , Doença Aguda , Biópsia , Seguimentos , Humanos , Miocárdio/metabolismo , Miocárdio/patologia , Transplante Homólogo
20.
Transplantation ; 76(5): 859-64, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-14501868

RESUMO

BACKGROUND: We investigated the occurrence of apoptosis during and after resolution of cardiac allograft rejection. Apoptosis could play different roles in graft survival depending on the target cells; thus, we also determined the cell types involved. METHODS: Endomyocardial biopsy specimens were evaluated during the first 6 months after transplantation as follows: group I, no current or prior rejection; group II, during an episode of moderate rejection; and group III, histologic resolution after an episode of moderate rejection. RESULTS: Groups II and III showed significantly increased apoptotic activity, indicated by increased caspase-8 and caspase-3 activity; however, activated caspase-3 was undetectable in group I. Activated caspase-3 was detected only in groups II and III. Terminal deoxynucleotide transferase-mediated dUTP nick-end labeling was detected in groups II and III but not group I and predominantly in inflammatory cells. CONCLUSIONS: Increased caspase activity and apoptosis of infiltrating cells not only occurs during acute cardiac allograft rejection but persists after histologic resolution. Thus, programmed cell death occurs beyond the period of histologic resolution and may play a role in regulation of the rejection process.


Assuntos
Apoptose/imunologia , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Transplante de Coração , Adulto , Idoso , Western Blotting , Caspase 3 , Caspase 8 , Caspase 9 , Caspases/metabolismo , Precursores Enzimáticos/metabolismo , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Pessoa de Meia-Idade , Miocárdio/enzimologia , Miocárdio/patologia , Transplante Homólogo
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