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1.
Echocardiography ; 35(3): 420-422, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29399902

RESUMO

A 56-year-old woman complained of atypical chest pain. At initial diagnostic workup, chest radiograph and transthoracic echocardiogram depict specific findings that raised the suspicion of pericardial agenesis. Cardiac computed tomography showed extreme levoposition of the heart and interposition of lung parenchyma between the aorta and the pulmonary artery. Those findings were consistent with the diagnosis of left-side pericardial agenesis, which was subsequently confirmed in cardiac magnetic resonance study. Left-side pericardial agenesis is rare and can result in nonspecific symptoms. An integrated multimodality imaging approach may provide incremental value on diagnosis approach. Its benign prognosis allows a conservative approach.


Assuntos
Pericárdio/anormalidades , Pericárdio/diagnóstico por imagem , Diagnóstico Diferencial , Ecocardiografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
2.
Europace ; 19(12): 2042-2046, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28430911

RESUMO

AIMS: Oversensing can interfere with biventricular pacing. Cardiac Resynchronization Therapy (CRT) output inhibition due to automatic brady mode change from a sensing to a pacing mode of a previously implanted pacemaker as it reached battery capacity depleted indicator has not been previously published in the medical literature. METHODS AND RESULTS: We report the first case of CRT output inhibition in a pacemaker dependent patient due to electrical stimuli from a previously right-sided implanted pacemaker, after unaware reversion of OVO mode (O = no chambers paced; V = ventricular sensing; O = no response to sensing) to backup VVI (V = ventricular pacing; V = ventricular sensing; I = inhibitory response to sensing) when it reached the elective replacement interval. CONCLUSION: This paper emphasizes the importance of knowing the distinct pacemaker brady mode behaviours after battery capacity depleted indicator has been reached, according to the pacemakers' manufacturer, including the possibility of automatic brady mode change from sensing to pacing mode. It also highlights the potential for severe bradycardia or asystole of this automatic brady mode change from a previously implanted pacemaker in pacemaker dependent patients submitted to CRT upgrade.


Assuntos
Estimulação Cardíaca Artificial , Dispositivos de Terapia de Ressincronização Cardíaca , Terapia de Ressincronização Cardíaca , Desfibriladores Implantáveis , Cardioversão Elétrica/instrumentação , Marca-Passo Artificial , Taquicardia Ventricular/terapia , Idoso , Estimulação Cardíaca Artificial/efeitos adversos , Terapia de Ressincronização Cardíaca/efeitos adversos , Cardioversão Elétrica/efeitos adversos , Estimulação Elétrica , Técnicas Eletrofisiológicas Cardíacas/instrumentação , Humanos , Masculino , Desenho de Prótese , Falha de Prótese , Tecnologia de Sensoriamento Remoto , Fatores de Risco , Processamento de Sinais Assistido por Computador , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologia , Telemetria/instrumentação , Resultado do Tratamento
3.
Echocardiography ; 34(7): 1002-1009, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28517046

RESUMO

PURPOSE: Management of patients with mitral stenosis (MS) depends heavily on the accurate quantification of mitral valve area (MVA) using echocardiography. All currently used two-dimensional (2D) methods have limitations. Estimation of MVA using the proximal isovelocity surface area (PISA) method with real time three-dimensional (3D) echocardiography may circumvent those limitations. We aimed to evaluate the accuracy of 3D direct measurement of PISA in the estimation of MVA. METHODS: Twenty-seven consecutive patients (median age of 63 years; 77.8% females) with rheumatic MS were prospectively studied. Transthoracic and transesophageal echocardiography with 2D and 3D acquisitions were performed on the same day. The reference method for MVA quantification was valve planimetry after 3D-volume multiplanar reconstruction. A semi-automated software was used to calculate the 3D flow convergence volume. RESULTS: Compared to MVA estimation using 3D planimetry, 3D PISA showed the best correlation (rho=0.78, P<.0001), followed by pressure half-time (PHT: rho=0.66, P<.001), continuity equation (CE: rho=0.61, P=.003), and 2D PISA (rho=0.26, P=.203). Bland-Altman analysis revealed a good agreement for MVA estimation with 3D PISA (mean difference -0.03 cm2 ; limits of agreement (LOA) -0.40-0.35), in contrast to wider LOA for 2D methods: CE (mean difference 0.02 cm2 , LOA -0.56-0.60); PHT (mean difference 0.31 cm2 , LOA -0.32-0.95); 2D PISA (mean difference -0.03 cm2 , LOA -0.92-0.86). CONCLUSIONS: MVA estimation using 3D PISA was feasible and more accurate than 2D methods. Its introduction in daily clinical practice seems possible and may overcome technical limitations of 2D methods.


Assuntos
Pesos e Medidas Corporais/métodos , Ecocardiografia Tridimensional/métodos , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/etiologia , Valva Mitral/diagnóstico por imagem , Doenças Reumáticas/complicações , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/anatomia & histologia , Estudos Prospectivos , Reprodutibilidade dos Testes
4.
Inorg Chem ; 55(20): 10343-10350, 2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27681055

RESUMO

Electrocrystallization from solutions of the dissymmetrical ET derivative cyanobenzene-ethylenedithio-tetrathiafulvalene (CNB-EDT-TTF) in the presence of triiodide I3- affords two different polymorphs (ß″ and κ) with the composition (CNB-EDT-TTF)4I3, both with a bilayer structure of the donors. These polymorphs differ in the packing patterns (ß″- and κ-type) of the donor molecules in each layer, in both cases with bifurcated C-N···H interactions effectively coupling head-to-head donor molecules between layer pairs. Two ß″ polymorphs can be obtained with different degrees of anionic ordering. In one disordered phase, ß″d, with a smaller unit cell, the triiodide anions are disordered over two possible positions in a channel between the donor bilayers, while in the ordered phase, ß″o, the triiodide anions occupy only one of those positions in this channel, leading to the doubling of the unit cell in the layer plane. These results for ß″ phases contrast with the κ polymorph previously reported, for which weaker disorder of the triiodide anions, over two possible orientations with 94 and 6% occupation factors, was observed. While the ß″ polymorphs remains metallic down to 1.5 K with a ρ300K/ρ4K resistivity ratio of 250, the κ polymorph presents a much smaller resistivity ratio in the range of 4-10 and superconductivity with an onset temperature of 3.5 K.

5.
J Cardiovasc Magn Reson ; 17: 61, 2015 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-26187817

RESUMO

BACKGROUND: Liver cirrhosis has been shown to affect cardiac performance. However cardiac dysfunction may only be revealed under stress conditions. The value of non-invasive stress tests in diagnosing cirrhotic cardiomyopathy is unclear. We sought to investigate the response to pharmacological stimulation with dobutamine in patients with cirrhosis using cardiovascular magnetic resonance. METHODS: Thirty-six patients and eight controls were scanned using a 1.5 T scanner (Siemens Symphony TIM; Siemens, Erlangen, Germany). Conventional volumetric and feature tracking analysis using dedicated software (CMR42; Circle Cardiovascular Imaging Inc, Calgary, Canada and Diogenes MRI; Tomtec; Germany, respectively) were performed at rest and during low to intermediate dose dobutamine stress. RESULTS: Whilst volumetry based parameters were similar between patients and controls at rest, patients had a smaller increase in cardiac output during stress (p = 0.015). Ejection fraction increase was impaired in patients during 10 µg/kg/min dobutamine as compared to controls (6.9 % vs. 16.5 %, p = 0.007), but not with 20 µg/kg/min (12.1 % vs. 17.6 %, p = 0.12). This was paralleled by an impaired improvement in circumferential strain with low dose (median increase of 14.4 % vs. 30.9 %, p = 0.03), but not with intermediate dose dobutamine (median increase of 29.4 % vs. 33.9 %, p = 0.54). There was an impaired longitudinal strain increase in patients as compared to controls during low (median increase of 6.6 % vs 28.6 %, p < 0.001) and intermediate dose dobutamine (median increase of 2.6%vs, 12.6 % p = 0.016). Radial strain response to dobutamine was similar in patients and controls (p > 0.05). CONCLUSION: Cirrhotic cardiomyopathy is characterized by an impaired cardiac pharmacological response that can be detected with magnetic resonance myocardial stress testing. Deformation analysis parameters may be more sensitive in identifying abnormalities in inotropic response to stress than conventional methods.


Assuntos
Cardiomiopatias/diagnóstico , Cardiotônicos/administração & dosagem , Dobutamina/administração & dosagem , Cirrose Hepática/complicações , Imagem Cinética por Ressonância Magnética/métodos , Contração Miocárdica , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Direita/diagnóstico , Função Ventricular Esquerda , Função Ventricular Direita , Idoso , Cardiomiopatias/etiologia , Cardiomiopatias/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Cirrose Hepática/diagnóstico , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Software , Volume Sistólico , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia
6.
Inorg Chem ; 54(4): 1354-62, 2015 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-25634799

RESUMO

The Fe(III) complexes Fe(5-Br-qsal)2Ni(dmit)2·solv with solv = CH2Cl2 (1) and (CH3)2CO (2) were synthesized, and their structural and magnetic properties were studied. While magnetization and Mössbauer spectroscopy data of 1 showed a gradual spin transition, compound 2 evidenced an abrupt transition with a thermal hysteresis of 13 K close to room temperature (T1/2 ↓ ∼273 K and T1/2 ↑ ∼286 K). A similar packing arrangement of segregated layers of cations and anions was found for 1 and 2. In both low-spin, LS, structures there are a large number of short intra- and interchain contacts. This number is lower in the high-spin, HS, phases, particularly in the case of 1. The significant loss of strong π-π interactions in the cationic chains and short contacts in the anionic chains in the HS structure of 1 leads to alternating strong and weak bonds between cations along the cationic chains and the formation of unconnected dimers along the anionic chains. This is consistent with a significant weakening of the extended interactions in 1. On the other hand, in the HS phase of 2 the 3D dimensionality of the short contacts observed in the LS phases is preserved. The effect of distinct solvent molecules on the intermolecular spacings explains the different spin crossover behaviors of the title compounds.

7.
Cardiovasc Drugs Ther ; 29(1): 31-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25749869

RESUMO

PURPOSE: Recent studies have shown that HIV infection is independently associated with heart failure. Diastolic dysfunction (DD) is frequent in HIV patients, but it is unclear whether this is an effect of the HIV infection itself or of the anti-retroviral therapy (ART). Our aim was to compare diastolic function in HIV treatment-naïve, HIV-ART patients and controls. METHODS: We prospectively enrolled 206 consecutive patients with HIV-1 infection and 30 controls, selected by frequency matching for age and sex. HIV patients were divided in two subgroups: ART-naïve (n = 88) and ART (n = 118). Diastolic function was assessed and graded by echocardiography, according to modern consensus criteria and using tissue Doppler analysis. RESULTS: Compared to controls, ART-naïve patients had lower E' velocities (E' septal: 10.2 ± 2.4 vs 11.9 ± 2.6 cm/s, p = 0.02), higher E/E' ratio (7.8 ± 1.9 vs 6.9 ± 1.6,p = 0.02) and higher prevalence of DD (19 % vs 3.3 %,p = 0.05). HIV patients under ART also had worse diastolic function compared to controls (E' septal: 10.3 ± 2.5 cm/s;p < 0.01; E/E'ratio: 8.0 ± 2.0,p < 0.01; DD prevalence: 23 %;p = 0.01), but no significant differences were found between ART-naïve and ART HIV subgroups. In multivariable logistic regression analysis, age and body mass index were the only independent predictors of reduced diastolic reserve in HIV patients. Regarding systolic function, there were no significant differences in ejection fraction or S' velocities between controls and HIV subgroups. CONCLUSIONS: HIV treatment-naïve patients have reduced diastolic reserve that is not worsened by ART. These data reinforce the association of diastolic dysfunction with the HIV infection itself and not with the anti-retroviral therapy.


Assuntos
Antirretrovirais/farmacologia , Diástole/efeitos dos fármacos , Infecções por HIV/fisiopatologia , Adulto , Antirretrovirais/uso terapêutico , Colesterol/sangue , Feminino , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Infecções por HIV/patologia , Ventrículos do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Sístole/efeitos dos fármacos
8.
Catheter Cardiovasc Interv ; 83(5): 791-5, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24285561

RESUMO

OBJECTIVES: Balloon valvuloplasty (BV) before transcatheter aortic implantation has been thought to be mandatory before the valve is implanted. We have explored the feasibility and safety of direct implantation of balloon expandable Edwards SAPIEN XT valve without prior balloon dilatation. BACKGROUND: Some complications after transcatheter aortic valve replacement (TAVR) have been associated with unwanted effects of BV, mainly the contribution to stroke and severe aortic regurgitation (AR) before the valve is implanted. Direct implantation with a self-expanding aortic valve has been recently reported. METHODS: From November 2011 to April 2012, ten patients were selected that met the following criteria in the transesophageal echocardiography (TEE): moderate calcification, homogeneous distribution of calcium, symmetrical opening of the valve, and some degree of aortic insufficiency. RESULTS: All patients had symptomatic aortic stenosis of a native valve and high surgical risk; six patients had the valve mildly calcified, in four patients the degree of calcification was moderate. The native valve was crossed and the prosthetic aortic valve was properly positioned in all cases and implanted in the correct position. No patient underwent post-dilatation and trivial AR was present in four patients. There were no adverse events (death, need for pacemaker, myocardial infarction, or stroke). At 30 days post-procedure, all patients were alive and had significant clinical improvement. CONCLUSIONS: Direct implantation of Edwards SAPIEN XT without prior BV in selected cases is feasible and safe. The number of patients in whom this technique would be applicable, and their impact on reducing complications has to be determined.


Assuntos
Estenose da Valva Aórtica/terapia , Cateterismo Cardíaco , Artéria Femoral , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/etiologia , Estenose da Valva Aórtica/fisiopatologia , Aortografia , Valvuloplastia com Balão , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/métodos , Ecocardiografia Doppler em Cores , Ecocardiografia Transesofagiana , Estudos de Viabilidade , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/métodos , Hemodinâmica , Humanos , Masculino , Seleção de Pacientes , Desenho de Prótese , Resultado do Tratamento
9.
Cardiovasc Drugs Ther ; 28(2): 191-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24515256

RESUMO

PURPOSE: Insulin resistance plays a central role in the pathophysiology of metabolic syndrome (MS). Its cardiac deleterious effects are characterized by an increase in fibrous tissue that increases myocardial stiffness and contributes to subclinical left ventricular diastolic dysfunction (LVDD) and heart failure with preserved ejection fraction in patients with MS. In addition to lifestyle counseling (LC), metformin treatment may attenuate or even reverse diastolic dysfunction in these patients. This trial aims to evaluate if treating non-diabetic patients with MS and LVDD with metformin in addition to LC improves diastolic function and assess its impact in functional capacity and health-related quality of life (HRQoL). DESIGN: MET-DIME is a phase II prospective, randomized, open-label, blinded-endpoint trial with a scheduled follow-up of 24 months. Fifty-four patients (adults 40-65 years old with AHA/NHLBI criteria of MS and rest LVDD) will be randomized by minimization to LC only or LC plus metformin (target dose of 1,000 mg twice daily). The primary endpoint will be change in mean of early diastolic mitral annular velocity, an echocardiographic parameter highly correlated with myocardial fibrosis (serial measurements will be performed at 6, 12 and 24 months). The secondary endpoints will include change in diastolic parameters at rest; metabolic, inflammatory and remodeling biomarkers; functional capacity; adipose tissue volumes and HRQoL. CONCLUSION: MET-DIME is a pragmatic trial designed to evaluate if adding metformin to the standard treatment of patients with MS improves diastolic dysfunction, assessing its impact in metabolic homeostasis, proinflammatory state, functional capacity and HRQoL.


Assuntos
Diástole/efeitos dos fármacos , Síndrome Metabólica/tratamento farmacológico , Metformina/uso terapêutico , Disfunção Ventricular Esquerda/tratamento farmacológico , Adulto , Idoso , Ecocardiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Função Ventricular Esquerda/efeitos dos fármacos
10.
J Stroke Cerebrovasc Dis ; 23(6): 1416-20, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24560245

RESUMO

BACKGROUND: Nowadays, the number of patients undergoing carotid artery stenting (CAS) is increasing rapidly, and these patients require follow-up to monitor the patency of the device and the potential development of an in-stent restenosis (ISR). METHODS: Patients undergoing CAS at our institution underwent duplex ultrasound (DUS) at 6 months, 12 months, and yearly thereafter, using a prespecified protocol. Restenosis was defined as a more than 50% diameter-reducing stenosis. Patients with DUS-diagnosed restenosis underwent carotid computerized tomography angiography (CTA) to confirm the presence of ISR. The frequency of restenosis was calculated by Kaplan-Meier survival estimates and was compared during a 2-year follow-up period. Interactions between restenosis and baseline variables were assessed using odds ratio. RESULTS: Between August 2007 and March 2012 were performed 100 procedures in 96 patients, with a median age of 72.9 years. The mean duration of follow-up was 29.2 months (±8.4). Restenosis occurred in 6 carotid arteries. The Kaplan-Meier estimate for the frequency of restenosis in 2 years was 6.0% and for severe restenosis was 3.0%. There were no occlusions. Diabetic patients seem to have a higher risk of ISR (OR=3.23, 95% CI .55-18.9). Carotid CTA was in agreement with the degree of stenosis estimated by DUS in all cases. CONCLUSIONS: Our results, using a DUS protocol and a specific peak systolic velocity threshold, showed that the frequency of restenosis at 2 years after CAS is 6.0% and so that CAS is probably a durable revascularization procedure. We emphasize the diagnostic agreement achieved between DUS and carotid CTA.


Assuntos
Artéria Carótida Primitiva/cirurgia , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/métodos , Stents , Idoso , Idoso de 80 Anos ou mais , Artéria Carótida Primitiva/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Ultrassonografia
11.
Rev Port Cir Cardiotorac Vasc ; 21(2): 107-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26182453

RESUMO

Valve blockage is one of the most serious complications of a mechanical prosthesis. Its annual incidence ranges from < 0.5% to 4.5% per patient/year. The diagnosis is not always done in time, as the clinical presentation is highly variable. In order to better understand the spectrum of clinical presentation of this complication, this paper presents the clinical case of a 64 year-old woman, whose personal medical history included aortic valve replacement with a monoleaflet Medtronic Hall® (Medtronic Inc, Minneapolis, MN) 21 mm, transferred from a peripheral hospital with the diagnosis of acute coronary syndrome of the anterolateral wall, with ST-segment depression and intermittent cardiogenic shock. The authors reviewed also the blockage mechanisms and its implications on the diagnosis and management of this potentially lethal condition.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Falha de Prótese , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade
12.
Liver Int ; 33(8): 1158-65, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23617332

RESUMO

BACKGROUND & AIMS: Cardiac dysfunction has been described in patients with cirrhosis. Conventional echocardiographic methods are frequently unable to detect abnormalities at rest and have limitations. We aimed to evaluate cardiac function in cirrhosis patients assessing: (i) left ventricular systolic function using speckle-tracking imaging; (ii) diastolic function using a tissue-Doppler based algorithm and comparing it with previously proposed definition of diastolic dysfunction (DD). METHODS: We included 109 hospitalized and ambulatory patients with cirrhosis and 18 healthy controls. Detailed echocardiographic evaluation was performed including tissue-Doppler and speckle-tracking analysis. RESULTS: Peak systolic longitudinal strain (PLS) was lower in patients [-19.99% (-21.88 to -18.71) vs -22.02% (-23.10 to -21.18), P = 0.003]. Ejection fraction was similar in patients and controls [64% (59-67) vs 61% (60-65), P = 0.42)]. Based on mitral-flow pattern, DD was present in 44 patients (40.4%). Patients without DD had higher cardiac output compared with those with DD [6.4 L/min (5.4-7.2) vs 5.6 L/min (4.6-6.8), P = 0.02]. Using a tissue-Doppler based definition, the prevalence of DD was 16.5%. No differences in haemodynamic variables were found in patients with and without this definition of DD. The agreement between the two definitions of DD was weak (kappa = 0.24, P = 0.003). Echocardiographic abnormalities in systolic and diastolic function were not different in compensated vs decompensated patients in different Child-Pugh classes or cirrhosis aetiologies. CONCLUSIONS: Patients with cirrhosis have systolic and diastolic cardiac dysfunction at rest. Newer echocardiographic techniques may identify patients with functional impairment more accurately than conventional methods, which are more influenced by flow conditions.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Diástole , Ecocardiografia Doppler , Cirrose Hepática/epidemiologia , Sístole , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda , Cardiomiopatias/epidemiologia , Cardiomiopatias/fisiopatologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Portugal , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Volume Sistólico , Disfunção Ventricular Esquerda/epidemiologia , Disfunção Ventricular Esquerda/fisiopatologia
13.
Inorg Chem ; 52(7): 3845-50, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23517057

RESUMO

We report the synthesis of the iron(III) complex of the hexadentate Schiff base ligand nsal2trien obtained from the condensation of triethylenetetramine and 2 equiv. of 2-hydroxy-1-naphthaldehyde. The study of the salt [Fe(nsal2trien)]SCN (1) by magnetic susceptibility measurements and Mössbauer spectroscopy reveals a rather unique behavior that displays thermally induced spin crossover (SCO) with two well-separated steps at 250 (gradual transition) and 142 K (steep transition). Single crystal X-ray structures were obtained at 294, 150, and 50 K, for the high spin (HS), intermediate (Int), and low spin (LS) phases. The HS and LS phases are isostructural, and based on a single Fe(III) site (either HS or LS) an unusual symmetry break occurs in the transition to the Int ordered phase, where the unit cell includes two distinct Fe(III) sites and is based on a repetition of the [HS-LS] motif. The two-step SCO behavior of 1 must result from the existence of structural constraints preventing the full conversion HS ↔ LS in a single step.

14.
Pacing Clin Electrophysiol ; 36(5): 559-69, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23521178

RESUMO

BACKGROUND: A permanent pacemaker (PPM) implantation is common after transcatheter aortic valve implantation (TAVI). We sought to evaluate requirements of pacing and incidence of pacemaker dependency during the first year after TAVI. METHODS: From August 2007 until May 2011, 65 patients underwent TAVI with self-expandable prosthesis. Five patients paced at baseline and two procedure-related deaths were excluded. Evaluation of ventricular pacing percentage (VP%) and look for spontaneous rhythm were performed at 3, 6, and 12 months. RESULTS: PPM implantation was required in 19/58 patients (33%). Mean VP% decreased between assessments (59% at 3 months, 48% at 6 months, 50% at 12 months), but overall VP% at 1 year was high (57% ± 43%) and most patients were paced ≥10% of time. A favorable annulus-to-aorta angle was associated with lower pacing requirements (60% of patients paced ≤10% of time vs 10% of patients paced >10% of time presented an angle ≤30°, P = 0.039). Pacemaker dependency was established in 27% of patients and could be predicted by the presence of porcelain aorta (odds ratio = 30, confidence interval 95% 1-638, P = 0.029). New postprocedural left bundle branch block (LBBB) had a negative impact on 1-year survival (58% vs 82% in non-LBBB group, P = 0.111). PPM implantation had no impact on 1-year survival. CONCLUSIONS: One third of patients required PPM after TAVI and full recovery of advanced conduction abnormalities seems unlikely. Unfavorable aortic root orientation may hinder the deployment of the valve and contribute to the continued impairment of the conduction system. Porcelain aorta was a strong predictor of pacemaker dependency.


Assuntos
Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/prevenção & controle , Implante de Prótese de Valva Cardíaca/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/diagnóstico , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Retrospectivos , Resultado do Tratamento
15.
Rev Port Cardiol ; 32(3): 229-38, 2013 Mar.
Artigo em Português | MEDLINE | ID: mdl-23337431

RESUMO

Isolated left ventricular noncompaction (LVNC) is a rare cardiomyopathy characterized by excessive and prominent trabeculations associated with deep recesses that communicate with the ventricular cavity. Determining the natural history of this condition has been hampered by differences in clinical features and prognosis in published series, which are partly the result of differing diagnostic criteria and the lack of management guidelines. This work aims to contribute to the characterization of isolated LVNC by analyzing an affected population in terms of clinical presentation, diagnosis, risk stratification, treatment and follow-up. We also discuss the most relevant data from the literature concerning this cardiomyopathy.


Assuntos
Miocárdio Ventricular não Compactado Isolado , Adolescente , Adulto , Idoso , Feminino , Humanos , Miocárdio Ventricular não Compactado Isolado/diagnóstico , Miocárdio Ventricular não Compactado Isolado/terapia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
Rev Port Cir Cardiotorac Vasc ; 20(3): 131-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25177739

RESUMO

Transcatheter valve-in-valve implantation for degenerated bioprostheses is an appealing alternative to reoperation in high-risk patients, and is technically feasible in both aortic and mitral positions. However, concurrent aortic and mitral transcatheter valve-in-valve procedures are seldom described. We aim to report our first case of double transapical valve-in-valve procedure for concomitant malfunction of aortic and mitral bioprostheses, in the same session.


Assuntos
Valva Aórtica/cirurgia , Bioprótese , Implante de Prótese de Valva Cardíaca/métodos , Próteses Valvulares Cardíacas , Valva Mitral/cirurgia , Idoso , Desenho de Equipamento , Implante de Prótese de Valva Cardíaca/instrumentação , Humanos , Masculino , Falha de Prótese , Substituição da Valva Aórtica Transcateter/instrumentação
17.
Catheter Cardiovasc Interv ; 80(7): 1099-104, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22511526

RESUMO

Type-A aortic dissection is a rare and often fatal complication following coronary artery bypass surgery (CABG). Corrective surgery seldom improves patient outcome. This report reviews and discusses endoprosthetic correction of type-A aortic dissection. A case of a transluminal correction of acute type-A aortic dissection one year after CABG in a 66-year-old male with a history of ischemic and severely compromised left ventricular function is presented. A prosthesis originally designed for the abdominal aorta was successfully used. Regular follow-up was performed and nearly 3 years post prosthesis implantation the patient is stable in New York Heart Association class II. To the authors' knowledge there are no other literature reports of endoprosthetic correction of a type-A aortic dissection in the context of CABG with saphenous grafts.


Assuntos
Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Ponte de Artéria Coronária/efeitos adversos , Procedimentos Endovasculares/instrumentação , Stents , Idoso , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/etiologia , Aneurisma Aórtico/diagnóstico , Aneurisma Aórtico/etiologia , Aortografia/métodos , Ecocardiografia Transesofagiana , Humanos , Masculino , Tomografia Computadorizada Multidetectores , Desenho de Prótese , Fatores de Tempo , Resultado do Tratamento
18.
Echocardiography ; 29(5): E112-4, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22329409

RESUMO

A 72-year-old man was admitted to the local hospital with non-ST elevation myocardial infarction. In the first 24 hours, a new onset apical murmur was heard. Transthoracic and transesophageal echocardiography showed interventricular septal (IVS) rupture and dissection of the right ventricle (RV) wall forming an echolucent pseudocavity that partially occupied the RV and communicated with the true RV cavity. Multislice computed tomography characterized in detail the IVS and RV wall dissection, and further showed the right coronary artery in the outer border of the RV and pseudocavity, excluding pericardial fluid. Despite surgical correction, progression to cardiogenic shock and death occurred 33 days after admission.


Assuntos
Ecocardiografia , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/etiologia , Ruptura do Septo Ventricular/complicações , Ruptura do Septo Ventricular/diagnóstico por imagem , Idoso , Evolução Fatal , Humanos , Masculino , Disfunção Ventricular Direita/cirurgia , Ruptura do Septo Ventricular/cirurgia
19.
Rev Port Cardiol ; 31(5): 395-8, 2012 May.
Artigo em Português | MEDLINE | ID: mdl-22498254

RESUMO

Percutaneous valve replacement for severe aortic stenosis has been shown to be an alternative treatment option for high surgical risk patients. We describe our first valve-in-valve procedure in a patient with a degenerated aortic bioprosthesis and severe regurgitation.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Implantação de Prótese/instrumentação , Idoso de 80 Anos ou mais , Bioprótese , Catéteres , Feminino , Humanos , Falha de Prótese
20.
Rev Port Cardiol ; 31(12): 795-801, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23159579

RESUMO

The Parachute is a novel left ventricular (LV) partitioning device that is deployed percutaneously in the left ventricle in patients with anteroapical regional wall motion abnormalities, dilated LV and systolic dysfunction after anterior myocardial infarction (MI). The implantable device is a partitioning membrane that isolates the dysfunctional region of the ventricle and decreases chamber volume. Data from the first-in-human clinical trial - the Percutaneous Ventricular Restoration in Chronic Heart Failure (PARACHUTE) trial- has shown that this new device is associated with significant and sustained LV volume reduction and improvement in LV hemodynamics and functional capacity in the 12 months after implantation, with a relatively low rate of clinical events, indicating that it may have a beneficial effect in the treatment of ischemic heart failure. We aim to describe our initial experience with implantation of the Parachute LV partitioning device and its short-term safety, defined as the successful delivery and deployment of the device.


Assuntos
Insuficiência Cardíaca/cirurgia , Isquemia Miocárdica/cirurgia , Implantação de Prótese/métodos , Procedimentos Cirúrgicos Cardíacos/métodos , Insuficiência Cardíaca/etiologia , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Próteses e Implantes
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