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1.
Ann Oncol ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38755096

RESUMO

BACKGROUND: Immune checkpoint inhibitors improve the efficacy of first-line chemotherapy for patients with programmed death-ligand 1 (PD-L1)-positive unresectable locally advanced/metastatic triple-negative breast cancer (aTNBC), but randomised data in rapidly relapsing aTNBC are scarce. PATIENTS AND METHODS: IMpassion132 (NCT03371017) enrolled patients with aTNBC relapsing <12 months after last chemotherapy dose (anthracycline and taxane required) or surgery for early TNBC. PD-L1 status was centrally assessed using SP142 before randomisation. Initially patients were enrolled irrespective of PD-L1 status. From August 2019, enrolment was restricted to PD-L1-positive (tumour immune cell ≥1%) aTNBC. Patients were randomised 1:1 to placebo or atezolizumab 1200 mg every 21 days with investigator-selected chemotherapy until disease progression or unacceptable toxicity. Stratification factors were chemotherapy regimen (carboplatin plus gemcitabine or capecitabine monotherapy), visceral (lung and/or liver) metastases and (initially) PD-L1 status. The primary endpoint was overall survival (OS), tested hierarchically in patients with PD-L1-positive tumours and then, if positive, in the modified intent-to-treat (mITT) population (all-comer patients randomised pre-August 2019). Secondary endpoints included progression-free survival (PFS), objective response rate (ORR) and safety. RESULTS: Among 354 patients with rapidly relapsing PD-L1-positive aTNBC, 68% had a disease-free interval of <6 months and 73% received carboplatin/gemcitabine. The OS hazard ratio was 0.93 (95% confidence interval 0.73-1.20, P = 0.59; median 11.2 months with placebo versus 12.1 months with atezolizumab). mITT and subgroup results were consistent. Median PFS was 4 months across treatment arms and populations. ORRs were 28% with placebo versus 40% with atezolizumab. Adverse events (predominantly haematological) were similar between arms and as expected with atezolizumab plus carboplatin/gemcitabine or capecitabine following recent chemotherapy exposure. CONCLUSIONS: OS, which is dismal in patients with TNBC relapsing within <12 months, was not improved by adding atezolizumab to chemotherapy. A biology-based definition of intrinsic resistance to immunotherapy in aTNBC is urgently needed to develop novel therapies for these patients in next-generation clinical trials.

2.
Front Cardiovasc Med ; 11: 1366444, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601046

RESUMO

Background: Mitral annular disjunction (MAD) refers to the arrhythmic mitral valve prolapse (MVP) syndrome associated with ventricular arrhythmias and sudden cardiac death. Although the pathophysiology of this disease is still under investigation, specific imaging criteria that establish the diagnosis have been recognized. In this article, we demonstrate most of these criteria using three-dimensional transthoracic echocardiography (3D-TTE) and provide added value in the management of MAD syndrome. Case presentation: A 50-year-old male patient with recent syncope and a history of mitral regurgitation (MR) and MAD was admitted to our clinic for further investigation. According to our protocol, the patient underwent a complete 3D-TTE, laboratory blood exams, and 24 h ambulatory electrocardiogram (ECG). Our investigation confirmed the presence of MAD syndrome with bileaflet prolapse, severe MR, and non-sustained ventricular tachycardia, necessitating an implantable cardioverter defibrillator (ICD) and surgical mitral valve repair. The 3D-TTE analysis of the mitral valve demonstrated mitral annular systolic expansion and systolic flattening of the saddle-shaped annulus and quantified the extent of the disjunction arc. Additionally, four-dimensional (4D) strain analysis of the left ventricle revealed the presence of fibrosis of the posteromedial papillary muscle and basal inferolateral wall, which are variables that are required for the diagnosis and therapeutic management of MAD syndrome. Conclusions: 3D-TTE and 4D strain offer valuable insights for diagnosing and managing patients with MAD syndrome. This method seems to correlate well with the other imaging modalities and could be included in the management protocol of MAD syndrome.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38508486

RESUMO

OBJECTIVE: Donation after circulatory death (DCD) donors offer the ability to expand the lung donor pool and ex vivo lung perfusion (EVLP) further contributes to this ability by allowing for additional evaluation and resuscitation of these extended criteria donors. We sought to determine the outcomes of recipients receiving organs from DCD EVLP donors in a multicenter setting. METHODS: This was an unplanned post hoc analysis of a multicenter, prospective, nonrandomized trial that took place during 2011 to 2017 with 3 years of follow-up. Patients were placed into 3 groups based off procurement strategy: brain-dead donor (control), brain-dead donor evaluated by EVLP, and DCD donors evaluated by EVLP. The primary outcomes were severe primary graft dysfunction at 72 hours and survival. Secondary outcomes included select perioperative outcomes, and 1-year and 3-years allograft function and quality of life measures. RESULTS: The DCD EVLP group had significantly higher incidence of severe primary graft dysfunction at 72 hours (P = .03), longer days on mechanical ventilation (P < .001) and in-hospital length of stay (P = .045). Survival at 3 years was 76.5% (95% CI, 69.2%-84.7%) for the control group, 68.3% (95% CI, 58.9%-79.1%) for the brain-dead donor group, and 60.7% (95% CI, 45.1%-81.8%) for the DCD group (P = .36). At 3-year follow-up, presence observed bronchiolitis obliterans syndrome or quality of life metrics did not differ among the groups. CONCLUSIONS: Although DCD EVLP allografts might not be appropriate to transplant in every candidate recipient, the expansion of their use might afford recipients stagnant on the waitlist a viable therapy.

6.
ASAIO J ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386980

RESUMO

Data regarding outcomes with Impella 5.5 are limited. The aim of this systematic review and meta-analysis was to summarize patient and treatment characteristics and early clinical outcomes among patients supported by Impella 5.5. A systematic literature search was conducted in PubMed, Scopus, and Cochrane databases from September 2019 to March 2023. Studies reporting outcomes in greater than or equal to 5 patients were included for review. Patient characteristics, treatment characteristics, and early clinical outcomes were extracted. Outcomes included adverse events, survival to hospital discharge, and 30 day survival. Random-effect models were used to estimate pooled effects for survival outcomes. Assessment for bias was performed using funnel plots and Egger's tests. Fifteen studies were included for qualitative review, representing 707 patients. Mean duration of support was 9.9 ± 8.2 days. On meta-analysis of 13 studies reporting survival outcomes, survival to hospital discharge was 68% (95% confidence interval [CI], 58-78%), and 30 day survival was 65% (95% CI, 56-74%) among patients with Impella devices predominantly supported by Impella 5.5 (>60%). There was significant study heterogeneity for these outcomes. Among 294 patients with Impella 5.5 only, survival to discharge was 78% (95% CI, 72-82%) with no significant study heterogeneity. This data present early benchmarks for outcomes with Impella 5.5 as clinical experience with these devices accrues.

7.
JACC Cardiovasc Imaging ; 17(5): 471-485, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38099912

RESUMO

BACKGROUND: The CLASP IID randomized trial (Edwards PASCAL TrAnScatheter Valve RePair System Pivotal Clinical Trial) demonstrated the safety and effectiveness of the PASCAL system for mitral transcatheter edge-to-edge repair (M-TEER) in patients at prohibitive surgical risk with significant symptomatic degenerative mitral regurgitation (DMR). OBJECTIVES: This study describes the echocardiographic methods and outcomes from the CLASP IID trial and analyzes baseline variables associated with residual mitral regurgitation (MR) ≤1+. METHODS: An independent echocardiographic core laboratory assessed echocardiographic parameters based on American Society of Echocardiography guidelines focusing on MR mechanism, severity, and feasibility of M-TEER. Factors associated with residual MR ≤1+ were identified using logistic regression. RESULTS: In 180 randomized patients, baseline echocardiographic parameters were well matched between the PASCAL (n = 117) and MitraClip (n = 63) groups, with flail leaflets present in 79.2% of patients. Baseline MR was 4+ in 76.4% and 3+ in 23.6% of patients. All patients achieved MR ≤2+ at discharge. The proportion of patients with MR ≤1+ was similar in both groups at discharge but diverged at 6 months, favoring PASCAL (83.7% vs 71.2%). Overall, patients with a smaller flail gap were significantly more likely to achieve MR ≤1+ at discharge (adjusted OR: 0.70; 95% CI: 0.50-0.99). Patients treated with PASCAL and those with a smaller flail gap were significantly more likely to sustain MR ≤1+ to 6 months (adjusted OR: 2.72 and 0.76; 95% CI: 1.08-6.89 and 0.60-0.98, respectively). CONCLUSIONS: The study used DMR-specific echocardiographic methodology for M-TEER reflecting current guidelines and advances in 3-dimensional echocardiography. Treatment with PASCAL and a smaller flail gap were significant factors in sustaining MR ≤1+ to 6 months. Results demonstrate that MR ≤1+ is an achievable benchmark for successful M-TEER. (Edwards PASCAL TrAnScatheter Valve RePair System Pivotal Clinical Trial [CLASP IID]; NCT03706833).


Assuntos
Cateterismo Cardíaco , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Valva Mitral , Valor Preditivo dos Testes , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Humanos , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Insuficiência da Valva Mitral/fisiopatologia , Masculino , Feminino , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Valva Mitral/fisiopatologia , Resultado do Tratamento , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/efeitos adversos , Idoso , Fatores de Risco , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/efeitos adversos , Fatores de Tempo , Idoso de 80 Anos ou mais , Próteses Valvulares Cardíacas , Estudos de Viabilidade , Medição de Risco , Desenho de Prótese , Ecocardiografia Tridimensional
8.
Am J Cardiol ; 213: 99-105, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38110022

RESUMO

The association, if any, between the effective regurgitant orifice area (EROA) to left ventricular end-diastolic volume (LVEDV) ratio and 1-year mortality is controversial in patients who undergo mitral transcatheter edge-to-edge repair (m-TEER) with the MitraClip system (Abbott Vascular, Santa Clara, CA). This study's objective was to determine the association between EROA/LVEDV and 1-year mortality in patients who undergo m-TEER with MitraClip. In patients with severe secondary (functional) mitral regurgitation (MR), we analyzed registry data from 11 centers using generalized linear models with the generalized estimating equations approach. We studied 525 patients with secondary MR who underwent m-TEER. Most patients were male (63%) and were New York Heart Association class III (61%) or IV (21%). Mitral regurgitation was caused by ischemic cardiomyopathy in 51% of patients. EROA/LVEDV values varied widely, with median = 0.19 mm2/ml, interquartile range [0.12,0.28] mm2/ml, and 187 patients (36%) had values <0.15 mm2/ml. Postprocedural mitral regurgitation severity was substantially alleviated, being 1+ or less in 74%, 2+ in 20%, 3+ in 4%, and 4+ in 2%; 1-year mortality was 22%. After adjustment for confounders, the logarithmic transformation (Ln) of EROA/LVEDV was associated with 1-year mortality (odds ratio 0.600, 95% confidence interval 0.386 to 0.933, p = 0.023). A higher Society of Thoracic Surgeons risk score was also associated with increased mortality. In conclusion, lower values of Ln(EROA/LVEDV) were associated with increased 1-year mortality in this multicenter registry. The slope of the association is steep at low values but gradually flattens as Ln(EROA/LVEDV) increases.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Humanos , Masculino , Feminino , Insuficiência da Valva Mitral/epidemiologia , Insuficiência da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Resultado do Tratamento , Sistema de Registros , América do Norte
9.
J Am Coll Cardiol ; 82(21): 1973-1985, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37968015

RESUMO

BACKGROUND: Exercise echocardiography is used for assessment of pulmonary circulation and right ventricular function, but limits of normal and disease-specific changes remain insufficiently established. OBJECTIVES: The objective of this study was to explore the physiological vs pathologic response of the right ventricle and pulmonary circulation to exercise. METHODS: A total of 2,228 subjects were enrolled: 375 healthy controls, 40 athletes, 516 patients with cardiovascular risk factors, 17 with pulmonary arterial hypertension, 872 with connective tissue diseases without overt pulmonary hypertension, 113 with left-sided heart disease, 30 with lung disease, and 265 with chronic exposure to high altitude. All subjects underwent resting and exercise echocardiography on a semirecumbent cycle ergometer. All-cause mortality was recorded at follow-up. RESULTS: The 5th and 95th percentile of the mean pulmonary artery pressure-cardiac output relationships were 0.2 to 3.5 mm Hg.min/L in healthy subjects without cardiovascular risk factors, and were increased in all patient categories and in high altitude residents. The 5th and 95th percentile of the tricuspid annular plane systolic excursion to systolic pulmonary artery pressure ratio at rest were 0.7 to 2.0 mm/mm Hg at rest and 0.5 to 1.5 mm/mm Hg at peak exercise, and were decreased at rest and exercise in all disease categories and in high-altitude residents. An increased all-cause mortality was predicted by a resting tricuspid annular plane systolic excursion to systolic pulmonary artery pressure <0.7 mm/mm Hg and mean pulmonary artery pressure-cardiac output >5 mm Hg.min/L. CONCLUSIONS: Exercise echocardiography of the pulmonary circulation and the right ventricle discloses prognostically relevant differences between healthy subjects, athletes, high-altitude residents, and patients with various cardio-respiratory conditions. (Right Heart International NETwork During Exercise in Different Clinical Conditions; NCT03041337).


Assuntos
Hipertensão Pulmonar , Disfunção Ventricular Direita , Humanos , Ecocardiografia sob Estresse/efeitos adversos , Circulação Pulmonar , Teste de Esforço/efeitos adversos , Ventrículos do Coração/diagnóstico por imagem , Função Ventricular Direita/fisiologia , Disfunção Ventricular Direita/diagnóstico por imagem
10.
Eur Heart J ; 44(46): 4862-4873, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37930776

RESUMO

BACKGROUND AND AIMS: For patients with symptomatic, severe tricuspid regurgitation (TR), early results of transcatheter tricuspid valve (TV) intervention studies have shown significant improvements in functional status and quality of life associated with right-heart reverse remodelling. Longer-term follow-up is needed to confirm sustained improvements in these outcomes. METHODS: The prospective, single-arm, multicentre TRISCEND study enrolled 176 patients to evaluate the safety and performance of transcatheter TV replacement in patients with ≥moderate, symptomatic TR despite medical therapy. Major adverse events, reduction in TR grade and haemodynamic outcomes by echocardiography, and clinical, functional, and quality-of-life parameters are reported to one year. RESULTS: Enrolled patients were 71.0% female, mean age 78.7 years, 88.0% ≥ severe TR, and 75.4% New York Heart Association classes III-IV. Tricuspid regurgitation was reduced to ≤mild in 97.6% (P < .001), with increases in stroke volume (10.5 ± 16.8 mL, P < .001) and cardiac output (0.6 ± 1.2 L/min, P < .001). New York Heart Association class I or II was achieved in 93.3% (P < .001), Kansas City Cardiomyopathy Questionnaire score increased by 25.7 points (P < .001), and six-minute walk distance increased by 56.2 m (P < .001). All-cause mortality was 9.1%, and 10.2% of patients were hospitalized for heart failure. CONCLUSIONS: In an elderly, highly comorbid population with ≥moderate TR, patients receiving transfemoral EVOQUE transcatheter TV replacement had sustained TR reduction, significant increases in stroke volume and cardiac output, and high survival and low hospitalization rates with improved clinical, functional, and quality-of-life outcomes to one year. Funded by Edwards Lifesciences, TRISCEND ClinicalTrials.gov number, NCT04221490.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Tricúspide , Humanos , Feminino , Idoso , Masculino , Insuficiência da Valva Tricúspide/epidemiologia , Insuficiência da Valva Tricúspide/cirurgia , Valva Tricúspide/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento , Cateterismo Cardíaco/métodos , Índice de Gravidade de Doença
11.
Europace ; 25(12)2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38006390

RESUMO

AIMS: The mechanisms of transition from regular rhythms to ventricular fibrillation (VF) are poorly understood. The concordant to discordant repolarization alternans pathway is extensively studied; however, despite its theoretical centrality, cannot guide ablation. We hypothesize that complex repolarization dynamics, i.e. oscillations in the repolarization phase of action potentials with periods over two of classic alternans, is a marker of electrically unstable substrate, and ablation of these areas has a stabilizing effect and may reduce the risk of VF. To prove the existence of higher-order periodicities in human hearts. METHODS AND RESULTS: We performed optical mapping of explanted human hearts obtained from recipients of heart transplantation at the time of surgery. Signals recorded from the right ventricle endocardial surface were processed to detect global and local repolarization dynamics during rapid pacing. A statistically significant global 1:4 peak was seen in three of six hearts. Local (pixel-wise) analysis revealed the spatially heterogeneous distribution of Periods 4, 6, and 8, with the regional presence of periods greater than two in all the hearts. There was no significant correlation between the underlying restitution properties and the period of each pixel. CONCLUSION: We present evidence of complex higher-order periodicities and the co-existence of such regions with stable non-chaotic areas in ex vivo human hearts. We infer that the oscillation of the calcium cycling machinery is the primary mechanism of higher-order dynamics. These higher-order regions may act as niduses of instability and may provide targets for substrate-based ablation of VF.


Assuntos
Ventrículos do Coração , Coração , Humanos , Arritmias Cardíacas , Fibrilação Ventricular/cirurgia , Potenciais de Ação/fisiologia
12.
Innovations (Phila) ; 18(5): 472-478, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37864489

RESUMO

OBJECTIVE: Obese patients with coronavirus disease 2019 (COVID-19)-associated acute respiratory failure (ARDS) often require prolonged intubation. However, data are sparse regarding optimal tracheostomy timing in obese adults with COVID-19 requiring venovenous extracorporeal membrane oxygenation (VV-ECMO). This study retrospectively describes the course of obese patients with COVID-19 who underwent tracheostomy on VV-ECMO between March 2020 and December 2022. METHODS: There were 62 participants with a median age of 43 (interquartile range [IQR] 33 to 53) years and a median body mass index of 42 (IQR 34 to 50) kg/m2 who received VV-ECMO for COVID-19-associated ARDS. Of those, 42 underwent tracheostomy on VV-ECMO, and 50% (n = 21) of the 42 patients underwent early (within 14 days of initiated ventilatory support) tracheostomy. RESULTS: Among patients who received tracheostomies, the combined respiratory tract and lung parenchymal bleeding rate was 29% (n = 12), but only 7% required surgical intervention for bleeding from the tracheostomy site (n = 3). The hospital length of stay (LOS) was 42 (IQR 36 to 57) days, and mortality rate was 38% (n = 16). Tracheostomy timing was not associated with differences in respiratory tract bleeding, mechanical ventilatory support duration, VV-ECMO support duration, intensive care unit LOS, hospital LOS, mortality, or survival probability. CONCLUSIONS: Although an individualized and holistic approach to clinical decision making continues to be necessary, the findings of this study suggest that early tracheostomy may be performed safely in obese patients with COVID-19 on VV-ECMO.


Assuntos
COVID-19 , Oxigenação por Membrana Extracorpórea , Síndrome do Desconforto Respiratório , Adulto , Humanos , Pessoa de Meia-Idade , COVID-19/complicações , COVID-19/epidemiologia , Traqueostomia , Estudos Retrospectivos , Síndrome do Desconforto Respiratório/terapia
14.
medRxiv ; 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37662394

RESUMO

Background: Repolarization alternans, defined as period-2 oscillation in the repolarization phase of the action potentials, provides a mechanistic link between cellular dynamics and ventricular fibrillation (VF). Theoretically, higher-order periodicities (e.g., periods 4, 6, 8,...) are expected but have minimal experimental evidence. Methods: We studied explanted human hearts obtained from recipients of heart transplantation at the time of surgery. Optical mapping of the transmembrane potential was performed after staining the hearts with voltage-sensitive fluorescent dyes. Hearts were stimulated at an increasing rate until VF was induced. Signals recorded from the right ventricle endocardial surface prior to induction of VF and in the presence of 1:1 conduction were processed using the Principal Component Analysis and a combinatorial algorithm to detect and quantify higher-order dynamics. Results were correlated to the underlying electrophysiological characteristics as quantified by restitution curves and conduction velocity. Results: A prominent and statistically significant global 1:4 peak (corresponding to period-4 dynamics) was seen in three of the six studied hearts. Local (pixel-wise) analysis revealed the spatially heterogeneous distribution of periods 4, 6, and 8, with the regional presence of periods greater than two in all the hearts. There was no significant correlation between the underlying restitution properties and the period of each pixel. Discussion: We present evidence of higher-order periodicities and the co-existence of such regions with stable non-chaotic areas in ex-vivo human hearts. We infer from the independence of the period to the underlying restitution properties that the oscillation of the excitation-contraction coupling and calcium cycling mechanisms is the primary mechanism of higher-order dynamics. These higher-order regions may act as niduses of instability that can degenerate into chaotic fibrillation and may provide targets for substrate-based ablation of VF.

15.
J Am Coll Cardiol ; 82(8): 721-734, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37587584

RESUMO

Valvular heart disease (VHD) is common and poses important challenges from the standpoints of diagnosis and therapeutic management. Clinical practice guidelines have been developed to help health care professionals to overcome these challenges and provide optimal management to patients with VHD. The American College of Cardiology, in collaboration with the American Heart Association, and the European Society of Cardiology, in collaboration with the European Association for Cardio-Thoracic Surgery, recently updated their guidelines on the management of VHD. Although these 2 sets of guidelines are generally concordant, there are some substantial differences between these guidelines, which may have significant implications for clinical practice. This review prepared on behalf of the EuroValve Consortium describes the consistencies and discrepancies between the guidelines and highlights the gaps in these guidelines and the future research perspectives to fill these gaps.


Assuntos
Cardiologia , Doenças das Valvas Cardíacas , Estados Unidos , Humanos , Doenças das Valvas Cardíacas/diagnóstico , Doenças das Valvas Cardíacas/terapia , Coração , American Heart Association , Pessoal de Saúde
16.
bioRxiv ; 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37205562

RESUMO

Background: Repolarization alternans, defined as period-2 oscillation in the repolarization phase of the action potentials, is one of the cornerstones of cardiac electrophysiology as it provides a mechanistic link between cellular dynamics and ventricular fibrillation (VF). Theoretically, higher-order periodicities (e.g., period-4, period-8,...) are expected but have very limited experimental evidence. Methods: We studied explanted human hearts, obtained from the recipients of heart transplantation at the time of surgery, using optical mapping technique with transmembrane voltage-sensitive fluorescent dyes. The hearts were stimulated at an increasing rate until VF was induced. The signals recorded from the right ventricle endocardial surface just before the induction of VF and in the presence of 1:1 conduction were processed using the Principal Component Analysis and a combinatorial algorithm to detect and quantify higher-order dynamics. Results: A prominent and statistically significant 1:4 peak (corresponding to period-4 dynamics) was seen in three of the six studied hearts. Local analysis revealed the spatiotemporal distribution of higher-order periods. Period-4 was localized to temporally stable islands. Higher-order oscillations (period-5, 6, and 8) were transient and primarily occurred in arcs parallel to the activation isochrones. Discussion: We present evidence of higher-order periodicities and the co-existence of such regions with stable non-chaotic areas in ex-vivo human hearts before VF induction. This result is consistent with the period-doubling route to chaos as a possible mechanism of VF initiation, which complements the concordant to discordant alternans mechanism. The presence of higher-order regions may act as niduses of instability that can degenerate into chaotic fibrillation.

18.
Am J Transplant ; 23(7): 1048-1057, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37059177

RESUMO

Nontuberculous mycobacteria are emerging pathogens, yet data on the epidemiology and management of extrapulmonary nontuberculous mycobacteria infections in orthotopic heart transplantation (OHT) and ventricular assist device (VAD) recipients are scarce. We retrospectively reviewed records of OHT and VAD recipients who underwent cardiac surgery at our hospital and developed Mycobacterium abscessus complex (MABC) infection from 2013 to 2016 during a hospital outbreak of MABC linked to heater-cooler units. We analyzed patient characteristics, medical and surgical management, and long-term outcomes. Ten OHT patients and 7 patients with VAD developed extrapulmonary M. abscessus subspecies abscessus infection. The median time from presumed inoculation during cardiac surgery to the first positive culture was 106 days in OHT and 29 days in VAD recipients. The most common sites of positive cultures were blood (n = 12), sternum/mediastinum (n = 8), and the VAD driveline exit site (n = 7). The 14 patients diagnosed when alive received combination antimicrobial therapy for a median of 21 weeks, developed 28 antibiotic-related adverse events, and underwent 27 surgeries. Only 8 (47%) patients survived longer than 12 weeks after diagnosis, including 2 patients with VAD who experienced long-term survival after an explantation of infected VADs and OHT. Despite aggressive medical and surgical management, OHT and VAD patients with MABC infection experienced substantial morbidity and mortality.


Assuntos
Transplante de Coração , Coração Auxiliar , Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Humanos , Coração Auxiliar/efeitos adversos , Estudos Retrospectivos , Transplante de Coração/efeitos adversos , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/epidemiologia
19.
Soft Matter ; 19(8): 1624-1641, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36752696

RESUMO

At the present time, there is no successful off-the-shelf small-caliber vascular graft (<6 mm) for the repair or bypass of the coronary or carotid arteries. In this study, we engineer a textile-reinforced hydrogel vascular graft. The textile fibers are circularly knitted into a flexible yet robust conduit to serve as the backbone of the composite vascular graft and provide the primary mechanical support. It is embedded in the hydrogel matrix which seals the open structure of the knitted reinforcement and mediates cellular response toward a faster reendothelialization. The mechanical properties of the composite vascular graft, including bursting strength, suture retention strength and radial compliance, significantly surpass the requirement for the vascular graft application and can be adjusted by altering the structure of the textile reinforcement. The addition of hydrogel matrix, on the other hand, improves the survival, adhesion and proliferation of endothelial cells in vitro. The composite vascular graft also enhances macrophage activation and upregulates M1 and M2 related gene expression, which further improves the endothelial cell migration that might favor the reendothelialization of the vascular graft. Taken together, the textile-reinforced hydrogel shows it potential to be a promising scaffold material to fabricate a tissue engineered vascular graft.


Assuntos
Células Endoteliais , Ativação de Macrófagos , Têxteis , Hidrogéis , Proliferação de Células , Macrófagos , Engenharia Tecidual
20.
Ann Thorac Surg ; 115(3): 566-574, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36623634

RESUMO

The Society of Thoracic Surgeons Adult Cardiac Surgery Database is the most mature and comprehensive cardiac surgery database. It is one of the most respected clinical data registries in health care, providing accurate risk-adjusted benchmarks, a foundation for quality measurement and improvement activities, and the ability to perform novel research. This report encompasses data from the years 2020 and 2021 and is the seventh in a series of reports that provide updated volumes, outcomes, database-related developments, and research summaries using the Adult Cardiac Surgery Database.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cirurgiões , Cirurgia Torácica , Adulto , Humanos , Avaliação de Resultados em Cuidados de Saúde , Sociedades Médicas , Bases de Dados Factuais
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