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

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-23879280

ABSTRACT

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.


Subject(s)
Adrenergic beta-Antagonists/administration & dosage , Electrocardiography, Ambulatory/drug effects , Long QT Syndrome/drug therapy , Long QT Syndrome/genetics , Romano-Ward Syndrome/drug therapy , Romano-Ward Syndrome/genetics , Adult , Analysis of Variance , Cohort Studies , Databases, Factual , Dose-Response Relationship, Drug , Drug Administration Schedule , Electrocardiography/drug effects , Electrocardiography, Ambulatory/methods , Female , Follow-Up Studies , Genetic Predisposition to Disease , Genotype , Heart Rate/drug effects , Humans , Long QT Syndrome/diagnosis , Male , Middle Aged , Risk Assessment , Romano-Ward Syndrome/diagnosis , Treatment Outcome
6.
EuroIntervention ; 9(3): 407-9, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23872655

ABSTRACT

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.


Subject(s)
Cardiac Catheterization , Heart Valve Prosthesis Implantation/methods , Mitral Valve Annuloplasty , Mitral Valve/surgery , Tricuspid Valve Stenosis/therapy , Tricuspid Valve/surgery , Aortic Valve/surgery , Bioprosthesis , Cardiac Catheterization/instrumentation , Echocardiography, Three-Dimensional , Echocardiography, Transesophageal , Female , Heart Failure/etiology , Heart Failure/therapy , Heart Valve Prosthesis , Heart Valve Prosthesis Implantation/adverse effects , Heart Valve Prosthesis Implantation/instrumentation , Humans , Middle Aged , Mitral Valve Annuloplasty/adverse effects , Mitral Valve Annuloplasty/instrumentation , Prosthesis Design , Prosthesis Failure , Severity of Illness Index , Tomography, X-Ray Computed , Treatment Outcome , Tricuspid Valve Stenosis/diagnosis , Tricuspid Valve Stenosis/etiology , Tricuspid Valve Stenosis/physiopathology
7.
Int J Cardiol ; 167(1): 73-9, 2013 Jul 15.
Article in English | MEDLINE | ID: mdl-22200184

ABSTRACT

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.


Subject(s)
Mineralocorticoid Receptor Antagonists/administration & dosage , Myocardial Infarction/mortality , Myocardial Infarction/therapy , Percutaneous Coronary Intervention , Tachycardia, Ventricular/mortality , Tachycardia, Ventricular/prevention & control , Adult , Aged , Aged, 80 and over , Case-Control Studies , Cohort Studies , Female , Follow-Up Studies , Humans , Injections, Intravenous , Male , Middle Aged , Percutaneous Coronary Intervention/methods , Prospective Studies , Time Factors , Treatment Outcome
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