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1.
J Biomech Eng ; 143(7)2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33704381

RESUMO

Pulmonary hypertension (PH) is a chronic progressive disease diagnosed when the pressure in the main pulmonary artery, assessed by right heart catheterization (RHC), is greater than 25 mmHg. Changes in the pulmonary vasculature due to the high pressure yield an increase in the right ventricle (RV) afterload. This starts a remodeling process during which the ventricle exhibits changes in shape and eventually fails. RV models were obtained from the segmentation of cardiac magnetic resonance images at baseline and 1-year follow-up for a pilot study that involved 12 PH and 7 control subjects. The models were used to create surface meshes of the geometry and to compute the principal, mean, and Gaussian curvatures. Ten global curvature indices were calculated for each of the RV endocardial wall reconstructions at the end-diastolic volume (EDV) and end-systolic volume (ESV) phases of the cardiac cycle. Statistical analysis of the data was performed to discern if there are significant differences in the curvature indices between controls and the PH group, as well as between the baseline and follow-up phases for the PH subjects. Six curvature indices, namely, the Gaussian curvature at ESV, the mean curvature at EDV and ESV, the L2-norm of the mean curvature at ESV, and the L2-norm of the major principal curvature at EDV and ESV, were found to be significantly different between controls and PH subjects (p < 0.05). We infer that these geometry measures could be used as indicators of RV endocardial wall morphology changes. Two global parameters, the Gaussian and mean curvatures at ESV, showed significant changes at the one-year follow-up for the PH subjects (p < 0.05). The aforementioned geometry measures to assess changes in RV shape could be used as part of a noninvasive computational tool to aid clinicians in PH diagnostic and progression assessment, and to evaluate the effectiveness of treatment.


Assuntos
Hipertensão Pulmonar
2.
Curr Hypertens Rep ; 16(12): 501, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25320018

RESUMO

Heart failure with preserved ejection fraction (HFpEF) is a major cause of HF-related morbidity and mortality, with no medical therapy proven to modify the underlying disease process and result in improvements in survival. With long-standing pulmonary venous congestion, a majority of HFpEF patients develop pulmonary hypertension (PH). Elevated pulmonary pressures have been shown to be a major determinant of mortality in this population. Given the paucity of available disease-modifying therapies for HFpEF, there has been a considerable interest in evaluating new therapeutic options specifically targeting PH in this patient population.


Assuntos
Insuficiência Cardíaca/complicações , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/terapia , Guias de Prática Clínica como Assunto , Volume Sistólico/fisiologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Hipertensão Pulmonar/mortalidade , Volume Sistólico/efeitos dos fármacos
3.
J Cardiovasc Magn Reson ; 16: 74, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25315015

RESUMO

BACKGROUND: CMR is considered the 'gold standard' for non-invasive LV and RV mass quantitation. This information is solely based on gradient-recalled echo (GRE) sequences while contrast dependent on intrinsic T1/T2 characteristics potentially offers superior image contrast between blood and myocardium. This study aims, for the first time in humans, to validate the SSFP approach using explanted hearts obtained from heart transplant recipients. Our objective is establish the correlation between and to validate steady-state free precession (SSFP) derived LV and RV mass vs. autopsy mass of hearts from cardiac transplants patients. METHODS: Over three-years, 58 explanted cardiomyopathy hearts were obtained immediately upon orthotopic heart transplantation from the OR. They were quickly cleaned, prepared and suspended in a saline-filled container and scanned ex vivo via SSFP-SA slices to define LV/RV mass. Using an automatic thresholding program, segmentation was achieved in combination with manual trimming (ATMT) of extraneous tissue incorporating 3D cardiac modeling performed by independent and blinded readers. The explanted hearts were then dissected with the ventricles surgically separated at the interventricular septum. Weights of the total heart not excluding papillary and trabecular myocardium, LV and RV were measured via high-fidelity scale. Linear regression and Bland-Altman plots were used to analyze the data. The intra-class correlation coefficient was used to assess intra-observer reliability. RESULTS: Of the total of 58 explanted hearts, 3 (6%) were excluded due to poor image quality leaving 55 patients (94%) for the final analysis. Significant positive correlations were found between total 3D CMR mass (450 ± 111 g) and total pathology mass (445 ± 116 g; r = 0.99, p < 0.001) as well as 3D CMR measured LV mass (301 ± 93 g) and the pathology measured LV mass (313 ± 96 g; r = 0.95, p < 0.001). Strong positive correlations were demonstrated between the 3D CMR measured RV mass (149 ± 46 g) and the pathology measured RV mass (128 ± 40 g; r = 0.76, p < 0.001). The mean bias between 3D-CMR and pathology measures for total mass, LV mass and RV mass were: 3.0 g, -16 g and 19 g, respectively. CONCLUSIONS: SSFP-CMR accurately determines total myocardial, LV and RV mass as compared to pathology weighed explanted hearts despite variable surgical removal of instrumentation (left and right ventricular assist devices, AICD and often apical core removals). Thus, this becomes the first-ever human CMR confirmation for SSFP now validating the distinction of 'gold standard'.


Assuntos
Cardiomiopatias/diagnóstico , Ventrículos do Coração/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Cardiomiopatias/patologia , Cardiomiopatias/cirurgia , Feminino , Transplante de Coração , Ventrículos do Coração/cirurgia , Humanos , Interpretação de Imagem Assistida por Computador , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Tamanho do Órgão , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
4.
Proc (Bayl Univ Med Cent) ; 37(5): 769-773, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39165822

RESUMO

Background: Statin therapy is widely utilized for preventing atherosclerotic cardiovascular disease, both as a primary and secondary measure. Despite the American Association for the Study of Liver Diseases' endorsement of statin use in cirrhotic patients, practitioners exhibit hesitancy, primarily due to concerns regarding hepatotoxicity. This study aimed to evaluate statin prescription patterns in cirrhotic patients by primary care physicians (PCPs) and cardiologists through a survey. Methods: A voluntary survey via Survey Monkey with nine objective-type questions was sent to 220 PCPs and 75 cardiologists within Allegheny Health Network. Survey results were collected, and a chi square test was used to compare the two groups. A P value ≤ 0.05 was considered statistically significant. Results: A total of 64 PCPs (29.1%) and 15 cardiologists (20%) completed the survey. Overall, 12.6% did not prescribe statins for primary prevention of atherosclerotic cardiovascular disease in compensated cirrhotic patients. While all cardiologists prescribed statins for secondary prevention, over 50% preferred lower-intensity options. Conversely, 14.1% of PCPs avoided statin prescriptions for secondary prevention. Cardiologists were significantly more inclined to prescribe statins, especially for cirrhosis due to metabolic dysfunction-associated steatotic liver disease compared to PCPs (73.3% vs 45.3%, P = 0.05). Conclusions: Despite increasing evidence favoring use of statins in cirrhosis for improving portal hemodynamics and decreasing ascites, hepatic encephalopathy, the incidence of hepatocellular carcinoma, and mortality, there is still hesitation on the part of prescribers for the fear of worsening liver disease. Wider dissemination of current guidelines and education practices may help to bridge this gap.

5.
Am J Cardiol ; 210: 266-272, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37973439

RESUMO

Remote cardiac rehabilitation (RCR) represents a promising, noninferior alternative to facility-based cardiac rehabilitation (FBCR). The comparable cost of RCR in US populations has yet to be extensively studied. The purpose of this prospective, patient-selected study of traditional FBCR versus a third-party asynchronous RCR platform was to assess whether RCR can be administered at a comparable cost and clinical efficacy to FBCR. Adult insured patients were eligible for enrollment after an admission for a coronary heart disease event. Patients selected either FBCR or Movn RCR, a 12-week telehealth intervention using an app-based platform and internet-capable medical devices. Clinical demographics, intervention adherence, cost-effectiveness, and hospitalizations at 1-year after enrollment were assessed from the Highmark claims database after propensity matching between groups. A total of 260 patients were included and 171 of those eligible (65.8%) received at least 1 cardiac rehabilitation session and half of the patients chose Movn RCR. The propensity matching produced a sample of 41 matched pairs. Movn RCR led to a faster enrollment and higher completion rates (80% vs 50%). The total medical costs were similar between Movn RCR and FBCR, although tended toward cost savings with Movn RCR ($10,574/patient). The cost of cardiac rehabilitation was lower in those enrolled in Movn RCR ($1,377/patient, p = 0.002). The all-cause and cardiovascular-related hospitalizations or emergency department visits in the year after enrollment in both groups were similar. In conclusion, this pragmatic study of patients after a coronary heart disease event led to equivalent total medical costs and lower intervention costs for an asynchronous RCR platform than traditional FBCR while maintaining similar clinically important outcomes.


Assuntos
Reabilitação Cardíaca , Doença da Artéria Coronariana , Telemedicina , Adulto , Humanos , Doença da Artéria Coronariana/reabilitação , Estudos Prospectivos , Custos e Análise de Custo
6.
bioRxiv ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38659908

RESUMO

Mechanical unloading and circulatory support with left ventricular assist devices (LVADs) mediate significant myocardial improvement in a subset of advanced heart failure (HF) patients. The clinical and biological phenomena associated with cardiac recovery are under intensive investigation. Left ventricular (LV) apical tissue, alongside clinical data, were collected from HF patients at the time of LVAD implantation (n=208). RNA was isolated and mRNA transcripts were identified through RNA sequencing and confirmed with RT-qPCR. To our knowledge this is the first study to combine transcriptomic and clinical data to derive predictors of myocardial recovery. We used a bioinformatic approach to integrate 59 clinical variables and 22,373 mRNA transcripts at the time of LVAD implantation for the prediction of post-LVAD myocardial recovery defined as LV ejection fraction (LVEF) ≥40% and LV end-diastolic diameter (LVEDD) ≤5.9cm, as well as functional and structural LV improvement independently by using LVEF and LVEDD as continuous variables, respectively. To substantiate the predicted variables, we used a multi-model approach with logistic and linear regressions. Combining RNA and clinical data resulted in a gradient boosted model with 80 features achieving an AUC of 0.731±0.15 for predicting myocardial recovery. Variables associated with myocardial recovery from a clinical standpoint included HF duration, pre-LVAD LVEF, LVEDD, and HF pharmacologic therapy, and LRRN4CL (ligand binding and programmed cell death) from a biological standpoint. Our findings could have diagnostic, prognostic, and therapeutic implications for advanced HF patients, and inform the care of the broader HF population.

7.
Curr Heart Fail Rep ; 10(1): 26-35, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23114592

RESUMO

Novel treatment of congestive heart failure (HF) involves utilizing unique pathways to improve upon contemporary therapies. Increasing the availability of cyclic guanosine monophosphate (cGMP) by inhibition of phosphodiesterase-5 (PDE5) is a relatively new, but promising therapeutic strategy. Preclinical studies suggest a favorable myocardial effect of PDE5 inhibitors by blocking adrenergic, hypertrophic and pro-apoptotic signaling, thereby supporting their use in HF. The clinical benefits of acute and chronic PDE5 inhibition on lung diffusion capacity, exercise performance and ejection fraction in humans are emerging and appear promising. Larger, controlled trials are now on-going to assess the safety, efficacy and tolerability of PDE5 inhibitors on morbidity and mortality in patients with both systolic and diastolic heart failure. If the results of these trials are positive, a new avenue for the treatment of HF will open, which will help curtail the societal effects of this costly and morbid disease.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Inibidores da Fosfodiesterase 5/uso terapêutico , GMP Cíclico/fisiologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/cirurgia , Transplante de Coração , Coração Auxiliar , Humanos , Óxido Nítrico/fisiologia , Transdução de Sinais/fisiologia
8.
J Med Device ; 17(2): 021006, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37152412

RESUMO

HeartPrinter is a novel under-constrained 3-cable parallel wire robot designed for minimally invasive epicardial interventions. The robot adheres to the beating heart using vacuum suction at its anchor points, with a central injector head that operates within the triangular workspace formed by the anchors, and is actuated by cables for multipoint direct gene therapy injections. Minimizing cable tensions can reduce forces on the heart at the anchor points while supporting rapid delivery of accurate injections and minimizing procedure time, risk of damage to the robot, and strain to the heart. However, cable tensions must be sufficient to hold the injector head's position as the heart moves and to prevent excessive cable slack. We pose a linear optimization problem to minimize the sum of cable tension magnitudes for HeartPrinter while ensuring the injector head is held in static equilibrium and the tensions are constrained within a feasible range. We use Karush-Kuhn-Tucker optimality conditions to derive conditional algebraic expressions for optimal cable tensions as a function of injector head position and workspace geometry, and we identify regions of injector head positions where particular combinations of cable tensions are optimally at minimum allowable tensions. The approach can rapidly solve for the minimum set of cable tensions for any robot workspace geometry and injector head position and determine whether an injection site is attainable.

9.
J Card Surg ; 27(4): 521-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22616563

RESUMO

OBJECTIVES: Acute refractory cardiogenic shock with early multisystem organ failure has a poor outcome without mechanical circulatory support. We review our experience with emergent peripheral cardiopulmonary support as a bridge to decision in these patients. METHODS: A retrospective review from January 2009 through December 2010 was conducted of 26 consecutive adult patients at a single institution with acute refractory cardiogenic shock who underwent salvage peripheral cardiopulmonary support. RESULTS: There were 18 men and 8 women with a mean age of 54 years (range 18 to 76). Indications for support: acute myocardial infarction (n = 16), decompensated chronic heart failure (n = 2), refractory arrhythmic arrest (n = 3), acute valvular pathology (n = 4), and unknown (n = 1). Patients with primary postcardiotomy shock were excluded. Median duration of support was 3 days (range 1 to 14). Decisions included: withdraw of support (n = 4), recovery (n = 5), and bridge to a procedure (n = 17). The procedures were percutaneous coronary intervention (n = 4), left ventricular assist device (n = 9), heart transplantation (n = 1), and miscellaneous cardiac surgery (n = 3). Overall survival to discharge was 65%. In the recovery and bridge to a procedure group, 78% were discharged from the hospital and survival at three months was 72%. CONCLUSIONS: Salvage peripheral cardiopulmonary support is a useful tool to rapidly stabilize acute refractory cardiogenic shock permitting an assessment of neurologic and end-organ viability.


Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Terapia de Salvação/métodos , Choque Cardiogênico/terapia , Adolescente , Adulto , Idoso , Algoritmos , Técnicas de Apoio para a Decisão , Oxigenação por Membrana Extracorpórea/instrumentação , Oxigenação por Membrana Extracorpórea/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxigenadores de Membrana , Estudos Retrospectivos , Terapia de Salvação/instrumentação , Terapia de Salvação/mortalidade , Choque Cardiogênico/etiologia , Choque Cardiogênico/mortalidade , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
10.
Heart Fail Clin ; 8(3): 353-72, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22748899

RESUMO

Among the many approaches for evaluating patients with pulmonary hypertension (PH), imaging plays a crucial role. The primary role of imaging is to identify the severity of PH based on noninvasive hemodynamic assessment and to evaluate right ventricular morphology and function. The major modalities used in current clinical practice for these purposes are echocardiography and cardiac magnetic resonance (CMR) imaging. This review discusses the merits, limitations, and clinical utility of several echocardiographic and CMR techniques used in the evaluation of PH. It also includes a brief discussion of the role of computed tomography and radionuclide imaging.


Assuntos
Hemodinâmica , Hipertensão Pulmonar/diagnóstico , Artéria Pulmonar , Função Ventricular Direita , Diástole , Ecocardiografia Doppler/métodos , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/patologia , Imagem Cinética por Ressonância Magnética/métodos , Programas de Rastreamento/métodos , Sístole , Tomografia Computadorizada por Raios X/métodos
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