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2.
Phys Med Biol ; 69(4)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38271727

RESUMO

Objective. This paper presents a novel approach for addressing the intricate task of diagnosing aortic valve regurgitation (AR), a valvular disease characterized by blood leakage due to incompetence of the valve closure. Conventional diagnostic techniques require detailed evaluations of multi-modal clinical data, frequently resulting in labor-intensive and time-consuming procedures that are vulnerable to varying subjective assessment of regurgitation severity.Approach. In our research, we introduce the multi-view video contrastive network, designed to leverage multiple color Doppler imaging inputs for multi-view video processing. We leverage supervised contrastive learning as a strategic approach to tackle class imbalance and enhance the effectiveness of our feature representation learning. Specifically, we introduce a contrastive learning framework to enhance representation learning within the embedding space through inter-patient and intra-patient contrastive loss terms.Main results. We conducted extensive experiments using an in-house dataset comprising 250 echocardiography video series. Our results exhibit a substantial improvement in diagnostic accuracy for AR compared to state-of-the-art methods in terms of accuracy by 9.60%, precision by 8.67%, recall by 9.01%, andF1-score by 8.92%. These results emphasize the capacity of our approach to provide a more precise and efficient method for evaluating the severity of AR.Significance. The proposed model could quickly and accurately make decisions about the severity of AR, potentially serving as a useful prescreening tool.


Assuntos
Catéteres , Doenças das Valvas Cardíacas , Humanos , Ecocardiografia
3.
Ochsner J ; 19(2): 107-115, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31258422

RESUMO

Background: Primary percutaneous coronary intervention (PCI) is the most frequently used treatment modality for patients presenting with ST elevation myocardial infarction (STEMI). Current professional society guidelines recommend culprit artery only PCI. Recent evidence suggests the potential benefit of multivessel PCI among patients with STEMI that is not complicated by cardiogenic shock. Methods: We systematically searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials for clinical studies of patients with STEMI, not complicated by cardiogenic shock, who underwent primary PCI between January 1966 and January 2018. We evaluated all-cause and cardiovascular mortality, reinfarction, and repeat revascularization among patients randomized to a multivessel PCI strategy compared to a culprit artery only PCI strategy. Results: Four randomized clinical trials with a total of 1,044 patients met the inclusion criteria. Five hundred and sixty-six patients underwent multivessel PCI, and 478 patients underwent culprit artery only PCI. Multivessel PCI reduced all the studied endpoints: total death, cardiac death, reinfarction, and repeat revascularization (all P values <0.05). Conclusion: To our knowledge, this is the largest metaanalysis of randomized controlled trials studying multivessel PCI vs culprit artery only PCI in STEMI patients without shock, among whom lesion severity was graded by angiography alone. We found that compared to culprit artery only PCI, the multivessel PCI strategy was beneficial in reducing all-cause and cardiovascular mortality, reinfarction, and the need for repeat revascularization.

4.
Catheter Cardiovasc Interv ; 87(2): 200-8, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25963829

RESUMO

INTRODUCTION: Clinical trials have shown a short-term benefit of drug-eluting stents (DES) compared to vascular brachytherapy (VBT) for treatment of in-stent restenosis (ISR). The long-term benefits of DES vs. VBT are conflicting in the literature. This study aimed to do a meta-analysis of long-term outcomes of DES compared to VBT for treatment of ISR. METHODS: PubMed, EMBASE, Cochrane Central and unpublished data were searched for cohort studies and randomized controlled trials (RCTs) that directly compared VBT to DES for the treatment of ISR. We evaluated the following outcomes at 2-5 years of follow-up: target lesion revascularization (TLR), target vessel revascularization (TVR), myocardial infarction (MI), stent thrombosis, cardiovascular (CV) mortality, and overall mortality. Heterogeneity was defined as I(2) values > 25%. Review Manager 5.1 was used for statistical analysis. RESULTS: We included 1,375 patients from five studies, of which three were RCTs. VBT was used to treat ISR in 685 (49.8%) patients. After a 2-5 year follow-up, no significant differences were found between treatment groups regarding MI (P = 0.49), stent thrombosis (P = 0.86), CV mortality (P = 0.35), and overall mortality (P = 0.71). TLR (OR 2.37; CI 1.55-3.63; P < 0.001) and TVR (OR 2.23; CI 1.01-4.94; P = 0.05) were significantly increased in patients who received VBT. CONCLUSION: This study suggests that DES are associated with decreased long-term revascularization procedures when compared to VBT for the treatment of ISR. This benefit does not appear to be associated with a significant reduction in mortality or myocardial infarction.


Assuntos
Braquiterapia , Reestenose Coronária/terapia , Stents Farmacológicos , Intervenção Coronária Percutânea/instrumentação , Idoso , Braquiterapia/efeitos adversos , Braquiterapia/mortalidade , Distribuição de Qui-Quadrado , Angiografia Coronária , Reestenose Coronária/diagnóstico , Reestenose Coronária/mortalidade , Reestenose Coronária/radioterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Razão de Chances , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Desenho de Prótese , Fatores de Risco , Trombose/etiologia , Fatores de Tempo , Resultado do Tratamento
5.
Open Heart ; 2(1): e000248, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26196021

RESUMO

BACKGROUND: Dual antiplatelet therapy is the standard of care after coronary stent placement but increases the bleeding risk. The effects of proton pump inhibitors (PPIs) on clopidogrel metabolism have been described, but the clinical significance is not yet definitive. We aimed to do an updated meta-analysis comparing outcomes in patients receiving clopidogrel with and without PPIs. METHODS: We systematically searched PubMed, Scopus and the Cochrane Central Register of Controlled Trials for randomised controlled trials (RCTs) and controlled observational studies in patients taking clopidogrel stratified by concomitant PPI use. Heterogeneity was examined with the Cochran Q test and I(2) statistics; p values inferior to 0.10 and I(2) >25% were considered significant for heterogeneity. RESULTS: We included 39 studies with a total of 214 851 patients, of whom 73 731 (34.3%) received the combination of clopidogrel and a PPI. In pooled analysis, all-cause mortality, myocardial infarction, stent thrombosis and cerebrovascular accidents were more common in patients receiving both drugs. However, among 23 552 patients from eight RCTs and propensity-matched studies, there were no significant differences in mortality or ischaemic events between groups. The use of PPIs in patients taking clopidogrel was associated with a significant reduction in the risk of gastrointestinal bleeding. CONCLUSIONS: The results of our meta-analysis suggest that PPIs are a marker of increased cardiovascular risk in patients taking clopidogrel, rather than a direct cause of worse outcomes. The pharmacodynamic interaction between PPIs and clopidogrel most likely has no clinical significance. Furthermore, PPIs have the potential to decrease gastrointestinal bleeding in clopidogrel users.

6.
J Interv Cardiol ; 28(3): 266-78, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25991422

RESUMO

INTRODUCTION: Both transfemoral (TF) and transapical (TA) routes are utilized for Transcatheter Aortic Valve Replacement (TAVR) using Edwards SAPIEN & SAPIEN XT valves. We intended to perform a meta-analysis comparing the complication rates between these two approaches in studies published before and after the standardized Valve Academic Research Consortium (VARC) definitions. METHODS: We performed a comprehensive electronic database search for studies published until January 2014 comparing TF and TA approaches using the Edwards SAPIEN/SAPIEN XT aortic valve. Studies were analyzed based on the following endpoints: 1-year mortality, 30-day mortality, stroke, new pacemaker implantation, bleeding, and acute kidney injury. RESULTS: Seventeen studies were included in the meta-analysis. Patients undergoing TA TAVR had a significantly higher logistic EuroSCORE (24.6 ± 12.9 vs. 21.3 ± 12.0; P < 0.001). The cumulative risks for 30-day mortality (RR 0.61; 95%CI 0.46-0.81; P = 0.001), 1-year mortality (RR 0.68; 95%CI 0.55-0.84; P < 0.001), and acute kidney injury (RR 0.53; 95%CI 0.38-0.73; P < 0.001) were significantly lower for patients undergoing TF as compared to TA approach. Both approaches had a similar incidence of 30-day stroke, pacemaker implantation, and major or life-threatening bleeding. Studies utilizing the VARC definitions and those pre-dating VARC yielded similar results. CONCLUSION: This meta-analysis demonstrates a decreased 30-day and 1-year mortality in TF TAVR as compared to TA TAVR. Post-procedure acute kidney injury and the need for renal replacement therapy are also significantly lower in the TF group. These differences hold true even after utilizing the standardized Valve Academic Research Consortium criteria.


Assuntos
Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter/métodos , Injúria Renal Aguda/etiologia , Hemorragia/etiologia , Humanos , Marca-Passo Artificial , Terapia de Substituição Renal , Acidente Vascular Cerebral/etiologia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/mortalidade
7.
Indian Pacing Electrophysiol J ; 15(5): 236-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27134440

RESUMO

Inappropriate ICD shocks are associated with increased mortality. They also impair patients' quality of life, increase hospitalizations, and raise health-care costs. Nearly 80% of inappropriate ICD shocks are caused by supraventricular tachycardia. Here we report the case of a patient who received a single-lead dual-chamber sensing ICD for primary prevention of sudden cardiac death and experienced inappropriate ICD shocks. V-A time, electrogram morphology, and response to antitachycardia pacing suggested atrioventricular nodal reentry tachycardia, which was confirmed in an electrophysiology study. Inspired by this case, we performed a literature review to discuss mechanisms for discrimination of supraventricular tachycardia with 1:1 A:V relationship from ventricular tachycardia with 1:1 retrograde conduction.

8.
J Card Fail ; 20(12): 931-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25230241

RESUMO

BACKGROUND: Chagas disease (CD) has been associated with an elevated risk of stroke, but current data are conflicting and prospective controlled studies are lacking. We performed a systematic review and meta-analysis examining the association between stroke and CD. METHODS: Pubmed, Embase, Cochrane Central, Latin American database, and unpublished data were searched with the use of the following terms: ("Chagas" OR "American trypanosomiasis") AND ("dilated" OR "ischemic" OR "idiopathic" OR "nonChagasic" OR "stroke" OR "cerebrovascular"). We included studies that reported prevalence or incidence of stroke in a CD group compared with a non-CD control group. Odds ratios (ORs) and their 95% confidence intervals (CIs) were computed with the use of a random-effects model. RESULTS: A total of 8 studies and 4,158 patients were included, of whom 1,528 (36.7%) had CD. Risk of stroke was elevated in the group of patients with CD (OR 2.10, 95% CI 1.17-3.78). Similar results were observed in a subanalysis of cardiomyopathy patients (OR 1.74, 95% CI 1.02-3.00) and in sensitivity analysis with removal of each individual study. Furthermore, exclusion of studies at higher risk for bias also yielded consistent results (OR 1.70, 95% CI 1.06-2.71). Subanalysis restricted to studies that included patients with the indeterminate form found no significant difference in the stroke prevalence between CD and non-CD patients (OR 3.10, 95% CI 0.89-10.77). CONCLUSIONS: CD is significantly associated with cerebrovascular events, particularly among patients with cardiomyopathy. These findings underline the need for prospective controlled studies in patients with Chagas cardiomyopathy to ascertain the prognostic significance of cerebrovascular events and to evaluate the role of therapeutic anticoagulation in primary prevention.


Assuntos
Cardiomiopatia Chagásica/diagnóstico , Cardiomiopatia Chagásica/epidemiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Idoso , Estudos de Casos e Controles , Comorbidade , Estudos Transversais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Prognóstico , Análise de Sobrevida
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