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2.
J Chem Theory Comput ; 18(1): 124-140, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-34931830

RESUMO

In Phys. Rev. Lett. 2021, 127, 023001 a reduced density matrix functional theory (RDMFT) was proposed for calculating energies of selected eigenstates of interacting many-Fermion systems. Here, we develop a solid foundation for this so-called w-RDMFT and present the details of various derivations. First, we explain how a generalization of the Ritz variational principle to ensemble states with fixed weights w in combination with the constrained search would lead to a universal functional of the one-particle reduced density matrix. To turn this into a viable functional theory, however, we also need to implement an exact convex relaxation. This general procedure includes Valone's pioneering work on ground state RDMFT as the special case w = (1,0, ···). Then, we work out in a comprehensive manner a methodology for deriving a compact description of the functional's domain. This leads to a hierarchy of generalized exclusion principle constraints which we illustrate in great detail. By anticipating their future pivotal role in functional theories and to keep our work self-contained, several required concepts from convex analysis are introduced and discussed.

5.
Ann Noninvasive Electrocardiol ; 18(4): 399-408, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23879280

RESUMO

BACKGROUND: In the long QT syndrome (LQTS) the effects of beta-blocker treatment on prevention of cardiac events differs according to the genotype. We aimed to assess the effect of beta-blocker treatment on QT/QTc duration in Type 1 LQTS (LQT1) and Type 2 LQTS (LQT2) patients. METHODS: 24-hour digital Holter ECG were recorded before and after beta-blocking therapy initiation in LQT1 (n = 30) and LQT2 patients (n = 16). QT duration was measured on consecutive 1-minute averaged QRS-T complexes leading to up to 1440 edited QT-RR pairs for each recording. We computed subject- and treatment-specific log/log QT/RR relationships which were used to correct the QT intervals. The QT duration was also evaluated at predefined heart rates and after correction using Bazett and Fridericia coefficients. RESULTS: At baseline, individual QT/RR coefficients were higher in LQT2 than in LQT1 patients (0.53 ± 0.10 vs. 0.40 ± 0.11, P < 0.001) and QT1000 was longer in LQT2 than in LQT1 patients (521 ± 38 vs. 481 ± 39 ms, P < 0.01). Beta-blockers significantly prolonged the mean RR interval (from 827 ± 161 to 939 ± 197 ms, P < 0.0001). The individual QT/RR coefficients were not significantly modified by beta-blockers. Beta-blocker treatment was associated with a prolongation of the QT1000 interval (from 481 ± 39 to 498 ± 43 ms, P < 0.01) in LQT1 patients but with a shortening in LQT2 patients (from 521 ± 38 to 503 ± 32 ms, P < 0.01). CONCLUSIONS: The effect of beta-adrenergic blockade on QTc duration is different in LQT1 and LQT2 patients. Our data suggest that, in LQT1 patients, the well-known positive effect of beta-blockade might be associated with a prolongation of QTc duration. The mechanisms of beta-blockade protection may be different in LQT1 and in LQT2 patients.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Eletrocardiografia Ambulatorial/efeitos dos fármacos , Síndrome do QT Longo/tratamento farmacológico , Síndrome do QT Longo/genética , Síndrome de Romano-Ward/tratamento farmacológico , Síndrome de Romano-Ward/genética , Adulto , Análise de Variância , Estudos de Coortes , Bases de Dados Factuais , Relação Dose-Resposta a Droga , Esquema de Medicação , Eletrocardiografia/efeitos dos fármacos , Eletrocardiografia Ambulatorial/métodos , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Frequência Cardíaca/efeitos dos fármacos , Humanos , Síndrome do QT Longo/diagnóstico , Masculino , Pessoa de Meia-Idade , Medição de Risco , Síndrome de Romano-Ward/diagnóstico , Resultado do Tratamento
6.
EuroIntervention ; 9(3): 407-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23872655

RESUMO

BACKGROUND: A 64-year-old female with rheumatic heart disease and multiple prior valve replacements presented with progressive oedema, ascites and dyspnoea on exertion. INVESTIGATION: Physical examination, transthoracic echocardiography, intracardiac echocardiography, transoesophageal echocardiography, right heart cathetherisation, computed tomography. DIAGNOSIS: She had a mitral homograft and Physio ring in the tricuspid position, and presented with severe bioprosthetic tricuspid valve stenosis (mean gradient 16 mmHg) and right-sided heart failure. TREATMENT: A transcatheter 26 mm Edwards SAPIEN valve was placed in the tricuspid position, resulting in near normalisation of tricuspid valve gradient. This represents the first report of a combined valve-in-ring (VIR) and valve in a homograft valve (VIV) SAPIEN implantation.


Assuntos
Cateterismo Cardíaco , Implante de Prótese de Valva Cardíaca/métodos , Anuloplastia da Valva Mitral , Valva Mitral/cirurgia , Estenose da Valva Tricúspide/terapia , Valva Tricúspide/cirurgia , Valva Aórtica/cirurgia , Bioprótese , Cateterismo Cardíaco/instrumentação , Ecocardiografia Tridimensional , Ecocardiografia Transesofagiana , Feminino , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/terapia , Próteses Valvulares Cardíacas , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/instrumentação , Humanos , Pessoa de Meia-Idade , Anuloplastia da Valva Mitral/efeitos adversos , Anuloplastia da Valva Mitral/instrumentação , Desenho de Prótese , Falha de Prótese , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Estenose da Valva Tricúspide/diagnóstico , Estenose da Valva Tricúspide/etiologia , Estenose da Valva Tricúspide/fisiopatologia
7.
Int J Cardiol ; 167(1): 73-9, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22200184

RESUMO

BACKGROUND: Aldosterone levels are high early after admission for ST elevation myocardial infarction (STEMI) concomitantly with high risk of sudden death and life-threatening ventricular arrhythmia. METHODS: We assessed the hypothesis that early aldosterone blockade on admission for primary percutaneous coronary intervention (PCI) may be associated with a reduction of life-threatening ventricular arrhythmia in a prospective cohort-nested case (n=159) versus historical control (n=623) study. All cases were treated on admission by 200mg IV bolus of potassium canrenoate, followed by 25mg PO spironolactone daily during the coronary care unit stay. The primary endpoint--in-hospital composite of death, resuscitated cardiac arrest and ventricular tachycardia--was assessed by logistic regression models adjusted on major pre-specified variables and validated by a bootstrap procedure and propensity-score based analyses. RESULTS: Aldosterone blockade was associated with lower risks of the primary endpoint (adjusted ORs 0.26, 95% CI [0.13-0.57]), resuscitated cardiac arrest (adjusted OR 0.39, 95% CI [0.16-0.94]), ventricular tachycardia or fibrillation (adjusted ORs 0.23, 95% CI [0.12-0.45]), as well as ventricular arrhythmia requiring resuscitation or anti-arrhythmic therapy (adjusted OR 0.41, 95% CI [0.19-0.88]). All findings were confirmed by the bootstrap procedure. The benefit on death or resuscitated cardiac arrest seemed sustained at 6month follow-up. CONCLUSIONS: Early aldosterone blockade in patients presenting for primary PCI for STEMI is associated with significant reductions in rates of life-threatening arrhythmia and cardiac arrest independent of the initial risk profile, heart failure or hemodynamic status. These findings support the concept of aldosterone blockade early after STEMI, warranting further confirmation by ongoing randomized trials.


Assuntos
Antagonistas de Receptores de Mineralocorticoides/administração & dosagem , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea , Taquicardia Ventricular/mortalidade , Taquicardia Ventricular/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Seguimentos , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/métodos , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
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