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1.
J Biomech Eng ; 137(8): 081009, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25994000

RESUMO

Heart failure is increasing at an alarming rate, making it a worldwide epidemic. As the population ages and life expectancy increases, this trend is not likely to change. Myocardial infarction (MI)-induced adverse left ventricular (LV) remodeling is responsible for nearly 70% of heart failure cases. The adverse remodeling process involves an extension of the border zone (BZ) adjacent to an MI, which is normally perfused but shows myofiber contractile dysfunction. To improve patient-specific modeling of cardiac mechanics, we sought to create a finite element model of the human LV with BZ and MI morphologies integrated directly from delayed-enhancement magnetic resonance (DE-MR) images. Instead of separating the LV into discrete regions (e.g., the MI, BZ, and remote regions) with each having a homogeneous myocardial material property, we assumed a functional relation between the DE-MR image pixel intensity and myocardial stiffness and contractility--we considered a linear variation of material properties as a function of DE-MR image pixel intensity, which is known to improve the accuracy of the model's response. The finite element model was then calibrated using measurements obtained from the same patient--namely, 3D strain measurements-using complementary spatial modulation of magnetization magnetic resonance (CSPAMM-MR) images. This led to an average circumferential strain error of 8.9% across all American Heart Association (AHA) segments. We demonstrate the utility of our method for quantifying smooth regional variations in myocardial contractility using cardiac DE-MR and CSPAMM-MR images acquired from a 78-yr-old woman who experienced an MI approximately 1 yr prior. We found a remote myocardial diastolic stiffness of C(0) = 0.102 kPa, and a remote myocardial contractility of T(max) = 146.9 kPa, which are both in the range of previously published normal human values. Moreover, we found a normalized pixel intensity range of 30% for the BZ, which is consistent with the literature. Based on these regional myocardial material properties, we used our finite element model to compute patient-specific diastolic and systolic LV myofiber stress distributions, which cannot be measured directly. One of the main driving forces for adverse LV remodeling is assumed to be an abnormally high level of ventricular wall stress, and many existing and new treatments for heart failure fundamentally attempt to normalize LV wall stress. Thus, our noninvasive method for estimating smooth regional variations in myocardial contractility should be valuable for optimizing new surgical or medical strategies to limit the chronic evolution from infarction to heart failure.


Assuntos
Imageamento por Ressonância Magnética , Contração Miocárdica , Infarto do Miocárdio/fisiopatologia , Modelagem Computacional Específica para o Paciente , Disfunção Ventricular Esquerda/fisiopatologia , Idoso , Feminino , Análise de Elementos Finitos , Humanos , Infarto do Miocárdio/diagnóstico
2.
Pulm Circ ; 13(4): e12299, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37868716

RESUMO

Patients with bronchopulmonary dysplasia (BPD) have shown clinical improvement after secundum atrial septal defect (ASD) closure. We sought to determine if this post-ASD closure improvement is secondary to the expected course in BPD patients or related to the closure itself. A novel BPD-ASD score was created to assess patients' clinical status (higher score = worse disease) and applied to 10 BPD-ASD inpatients weighing ≤ 10 kg who underwent ASD closure. The score and its subcomponents were retrospectively calculated serially ranging from 8 weeks pre- to 8 weeks post-intervention, and pre- and post-intervention score slopes were created. These slopes were compared using mixed regression modeling with an interaction term. There was a significant difference in pre- versus post-intervention slope with the most score drop the first week post-intervention (-2.1 + /- 0.8, p = 0.014). The mean score also dropped through weeks 2 (slope -0.8 + /- 0.8, p = 0.013) and 4 (slope -1.0 + /- 0.5, p = 0.001) post-intervention. There was a significant difference in pre- and post-intervention slopes for diuretics (p = 0.018) and the combined score of respiratory support, FiO2 need, and respiratory symptoms (p = 0.018). This study demonstrated significant improvement in BPD-ASD score, diuretic need, and respiratory status after ASD closure in BPD-ASD patients ≤ 10 kg that was outside of the natural course of BPD. Our study was limited by its small, single-center, retrospective nature. Future studies should be performed in a larger multicenter population to both validate the scoring system and compare to non-intervention infants.

3.
Am J Cardiol ; 166: 97-106, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34973687

RESUMO

There is a lack of current, multi-institutional data regarding hospital outcomes of infants with interrupted aortic arch (IAA). We analyzed the Pediatric Health Information System database to identify infants with IAA who underwent repair during 2004 to 2019. We classified patients as simple or complex based on associated heart defects. We evaluated factors associated with hospital mortality and complications related to 22q11.2 deletion syndrome (22q11.2del) using mixed logistic regression, accounting for hospital clustering. In 1,283 infants included (904 simple, 379 complex), mortality was higher in the complex group (11.7% vs 4.4%, p <0.001). Factors associated with mortality in the simple group were low birth weight (adjusted risk ratio [aRR] 3.77, 95% confidence interval [95% CI] 1.83 to 7.77), non-22q11.2del genetic conditions (aRR 6.44, 95% CI 1.73 to 23.96), and gastrointestinal anomalies (aRR 8.47, 95% CI 3.12 to 22.95), whereas surgery between 2012 and 2015 (aRR 0.36, 95% CI 0.13 to 0.99) was protective. In the complex group, factors associated with mortality were male (aRR 2.32, 95% CI 1.10 to 4.24) and central nervous system anomalies (aRR 3.73, 95% CI 1.62 to 8.59). Compared with their nonsyndromic counterparts, infants with simple IAA and 22q11.2del were at higher risk of sepsis (aRR 1.63, 95% CI 1.02 to 2.39) and gastrostomy tube placement (aRR 3.18, 95% CI 2.13 to 4.74), and infants with complex IAA and 22q11.2del were at higher risk of gastrostomy tube placement (aRR 2.42, 95% CI 1.20 to 4.88). In conclusion, presence of complex cardiac lesions is associated with increased mortality after IAA repair. The co-occurrence of extracardiac congenital anomalies and non-22q11.2del genetic conditions elevates mortality risk. Presence of 22q11.2del is associated with hospital complications.


Assuntos
Coartação Aórtica , Síndrome de DiGeorge , Cardiopatias Congênitas , Aorta Torácica/anormalidades , Aorta Torácica/cirurgia , Coartação Aórtica/complicações , Criança , Deleção Cromossômica , Síndrome de DiGeorge/complicações , Feminino , Hospitais , Humanos , Lactente , Masculino
4.
J Thorac Cardiovasc Surg ; 160(6): 1539-1540, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32595032
8.
J Surg Educ ; 64(3): 158-61, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17574177

RESUMO

HYPOTHESIS: Chronic pancreatitis is a risk factor for pancreatic cancer. The association between these 2 disease processes is not well known. We present 3 unusual cases of pancreatitis associated with pancreatic cancer and review the possible mechanisms that can cause pancreatitis to degenerate into pancreatic cancer. DESIGN: A case series reviewing 3 unusual cases of chronic pancreatitis associated with pancreatic cancer. The patients' charts are reviewed, and a literature search is performed looking for chronic pancreatitis associated with pancreatic cancer. SETTING: The cases were performed at a small community hospital in New York City, New York. PARTICIPANTS: The surgeons involved are experienced pancreatic surgeons with a large referral group. The endoscopies were performed by gastroenterologists with years of experience in biliary and pancreatic disease. RESULTS: The cases and the literature review support the hypothesis that there is an association between chronic pancreatitis and pancreatic cancer. CONCLUSIONS: Three unusual case of chronic pancreatitis, 2 with synchronous and 1 with metachronous malignancies, are presented. The pathway of benign to malignant change is reviewed, and the constant awareness that pancreatitis is associated with malignancy must be kept in mind.


Assuntos
Adenocarcinoma/patologia , Neoplasias Pancreáticas/etiologia , Pancreatite Crônica/complicações , Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatectomia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Pancreatite Crônica/cirurgia
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