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1.
JACC Cardiovasc Imaging ; 5(8): 769-77, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22897989

RESUMO

OBJECTIVES: We studied in a multicenter setting the accuracy and reproducibility of 3-dimensional echocardiography (3DE)-derived measurements of left atrial volume (LAV) using new, dedicated volumetric software, side by side with 2-dimensional echocardiography (2DE), using cardiac magnetic resonance (CMR) imaging as a reference. BACKGROUND: Increased LAV is associated with adverse cardiovascular outcomes. Although LAV measurements are routinely performed using 2DE, this methodology is limited because it is view dependent and relies on geometric assumptions regarding left atrial shape. Real-time 3DE is free of these limitations and accordingly is an attractive alternative for the evaluation of LAV. However, few studies have validated 3DE-derived LAV measurements against an accepted independent reference standard, such as CMR imaging. METHODS: We studied 92 patients with a wide range of LAV who underwent CMR (1.5-T) and echocardiographic imaging on the same day. Images were analyzed to obtain maximal and minimal LAV: CMR images using standard commercial tools, 2DE images using a biplane area-length technique, and 3DE images using Tomtec LA Function software. Intertechnique comparisons included linear regression and Bland-Altman analyses. Reproducibility of all 3 techniques was assessed by calculating the percentage of absolute differences in blinded repeated measurements. Kappa statistics were used to compare 2DE and 3DE classification of normal/enlarged against the CMR reference. RESULTS: 3DE-derived LAV values showed higher correlation with CMR than 2DE measurements (r = 0.93 vs. r = 0.74 for maximal LAV; r = 0.88 vs. r = 0.82 for minimal LAV). Although 2DE underestimated maximal LAV by 31 ± 25 ml and minimal LAV by 16 ± 32 ml, 3DE resulted in a minimal bias of -1 ± 14 ml for maximal LAV and 0 ± 21 ml for minimal LAV. Interobserver and intraobserver variability of 2DE and 3DE measurements of maximal LAV were similar (7% to 12%) and approximately 2 times higher than CMR (4% to 5%). 3DE classified enlarged atria more accurately than 2DE (kappa: 0.88 vs. 0.71). CONCLUSIONS: Compared with CMR reference, 3DE-derived LAV measurements are more accurate than 2DE-based analysis, resulting in fewer patients with undetected atrial enlargement.


Assuntos
Volume Cardíaco , Ecocardiografia Tridimensional , Idoso , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Função Ventricular Esquerda
2.
Int J Cardiol ; 158(3): 353-8, 2012 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-21315460

RESUMO

BACKGROUND: This study sought to compare cardiac magnetic resonance imaging (CMR) with dual source computed tomography (DSCT) for analysis of aortic root dimensions prior to transcatheter aortic valve implantation (TAVI). In addition, the potential impact of CMR and DSCT measurements on TAVI strategy defined by 2D-transesophageal echocardiography (TEE) was evaluated. METHODS: Aortic root dimensions were measured using CMR and DSCT in 58 patients referred for evaluation of TAVI. The TAVI strategy (choice of prosthesis size and decision to implant) was based on 2D-TEE annulus measurements. RESULTS: CMR and DSCT aortic root measurements showed an overall good correlation (r=0.86, p<0.001 for coronal aortic annulus diameters). There was also a good correlation between TEE and CMR as well as between TEE and DSCT for measurement of sagittal aortic annulus diameters (r=0.69, p<0.001). However, annulus diameters assessed by TEE (22.1±2.3mm) were significantly smaller than coronal aortic annulus diameters assessed by CMR (23.4±1.8mm, p<0.001) or DSCT (23.6±1.8, p<0.001). Regarding TAVI strategy, the agreement between TEE and sagittal CMR (kappa=0.89) as well as sagittal DSCT measurements (kappa=0.87) was statistically perfect. However, decision based on coronal CMR- or MSCT measurements would have modified TAVI strategy as compared to a TEE based choice in a significant number of patients (22% to 24%). CONCLUSION: In patients referred for TAVI, CMR measurements of aortic root dimensions show a good correlation with DSCT measurements and thus CMR may be an alternative 3D-imaging modality. Aortic annulus measurements using TEE, CMR and DSCT were close but not identical and the method used has important potential implications on TAVI strategy.


Assuntos
Aorta/anatomia & histologia , Estenose da Valva Aórtica/cirurgia , Aortografia/métodos , Implante de Prótese de Valva Cardíaca/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/diagnóstico por imagem , Aortografia/estatística & dados numéricos , Cateterismo Cardíaco , Feminino , Próteses Valvulares Cardíacas , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Variações Dependentes do Observador , Tamanho do Órgão , Estudos Prospectivos , Insuficiência Renal Crônica/complicações , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Ultrassonografia
3.
J Am Coll Cardiol ; 56(13): 1056-62, 2010 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-20846606

RESUMO

OBJECTIVES: This study evaluated the value of systolic and diastolic deformation indexes determined by strain-encoded imaging to predict persistent severe dysfunction at follow-up in patients after reperfused acute myocardial infarction (AMI) in comparison with late gadolinium enhancement (LGE). BACKGROUND: Animal studies suggest that regional diastolic function provides information about myocardial viability after AMI. However, data in humans are sparse. METHODS: Twenty-six patients underwent magnetic resonance imaging 3 ± 1 days after successfully reperfused ST-segment elevation myocardial infarction and at a follow-up of 6 months. Cine, strain-encoded, and LGE images were acquired. Peak systolic circumferential strain (E(cc)) and early diastolic strain rate (E(cc)/s) were calculated for each segment at baseline and at follow-up. A cutoff E(cc) value of -9% was used to define severe dysfunction at follow-up. RESULTS: A total of 312 segments were analyzed; 119 segments showed abnormal baseline function. Thirty-five segments showed severe dysfunction at follow-up, which was defined as E(cc) at follow-up <9%. The area under the curve for E(cc)/s was 0.82 (95% confidence interval [CI]: 0.72 to 0.89), for E(cc) 0.74 (95% CI: 0.64 to 0.83), and for LGE 0.85 (95% CI: 0.77 to 0.92). A comparison of receiver-operating characteristic curves demonstrates that LGE is not significantly different than E(cc)/s but is significantly different than E(cc) (p = 0.32 vs. p < 0.05) for prediction of severe dysfunction at follow-up. CONCLUSIONS: Regional diastolic function provides similar accuracy to predict persistent severe dysfunction at follow-up to LGE and is superior to regional systolic function in patients after AMI. Diastolic deformation indexes may serve as a new parameter for assessment of viability in patients after AMI. (SENC in AMI Study; NCT00752713).


Assuntos
Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico , Estudos de Casos e Controles , Diástole , Seguimentos , Gadolínio , Humanos , Imagem Cinética por Ressonância Magnética , Infarto do Miocárdio/complicações , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Compostos Radiofarmacêuticos , Sístole , Disfunção Ventricular Esquerda/etiologia
4.
Invest Radiol ; 45(8): 502-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20531014

RESUMO

OBJECTIVES: To visualize the coronary sinus using magnetic resonance (MR), and to demonstrate the feasibility of MR-guided intubation of the cardiac venous system (CVS) in swine. MATERIALS AND METHODS: A total of 6 pigs were investigated. All experiments were performed using an interventional 1.5-Tesla MRI system. The CVS was visualized using an inversion-recovery navigator-gated whole-heart steady-state free-precession sequence after administration of gadobenate dimeglumine contrast agent. The coronary sinus was then intubated under MR-guidance with a passive MR-compatible guidewire modified by incorporation of iron oxide markers for improved visualization and a nonbraided Cobra-catheter. MR-guided interventions were monitored using a steady-state free-precession real-time imaging sequence. Time needed was measured for MR-guided intubation of the CVS and compared with the time needed for fluoroscopy guided intubation of the CVS. RESULTS: Visualization and intubation of the coronary sinus and its site branches was feasible in all cases. Time spent for MR-guided intubation of the CVS was comparable to time spent for fluoroscopy-guided intubation (8.2 +/- 2 minutes vs. 8.3 +/- 1.3 minutes; P = 0.85). CONCLUSIONS: MR-visualization and MR-guided intubation of the coronary sinus and its side branches is feasible. The feasibility of MR-guided intubation of the CVS might have relevance for procedures like cardiac resynchronization therapy and percutaneous transcatheter mitral annuloplasty, requiring improved 3-dimensional knowledge about cardiac vein anatomy in the near future.


Assuntos
Vasos Coronários/anatomia & histologia , Intubação/métodos , Imageamento por Ressonância Magnética/instrumentação , Animais , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/métodos , Seio Coronário/anatomia & histologia , Vasos Coronários/patologia , Estudos de Viabilidade , Feminino , Fluoroscopia/instrumentação , Fluoroscopia/métodos , Imageamento Tridimensional , Intubação/instrumentação , Meglumina/análogos & derivados , Compostos Organometálicos , Suínos , Fatores de Tempo
5.
Radiology ; 255(3): 799-804, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20501717

RESUMO

PURPOSE: To assess the feasibility and effectiveness of rapid right ventricular pacing with a magnetic resonance (MR)-compatible pacemaker lead during MR-guided aortic valvuloplasty. MATERIALS AND METHODS: This study was approved by the institutional animal research committee. Seven pigs were investigated. All experiments were performed with an interventional 1.5-T MR system. Interventions were monitored with a steady-state free precession real-time imaging sequence. An MR-compatible pacemaker lead was placed in the right ventricular apex with MR guidance before valvuloplasty. After positioning the balloon in valve position, valvuloplasty was performed with rapid right ventricular rapid pacing at a heart rate of 180 beats per minute to minimize cardiac output. RESULTS: Positioning of the pacemaker lead with MR guidance was feasible in all swine (sensing, 6 mV +/- 1; threshold, 1 V +/- 0.5). The lead could be seen on steady-state free precession images without inducing any artifacts. Rapid right ventricular pacing was feasible in all swine, and balloon stability at the time of inflation was achieved with no balloon movement. Aortic valvuloplasty was successfully accomplished in all experiments. CONCLUSION: Rapid right ventricular pacing with an MR-compatible pacemaker lead is feasible and effective.


Assuntos
Estimulação Cardíaca Artificial/métodos , Cateterismo , Ventrículos do Coração , Imagem por Ressonância Magnética Intervencionista , Animais , Aorta , Meios de Contraste , Dextranos , Estudos de Viabilidade , Feminino , Óxido Ferroso-Férrico , Hemodinâmica , Nanopartículas de Magnetita , Suínos
6.
Acta Cardiol ; 65(2): 161-70, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20458823

RESUMO

OBJECTIVE: Cardiac resynchronization therapy (CRT) provides a therapeutic option for patients with congestive heart failure (CHF). There is evidence that the optimal pacing site (OIS) is vicinal to the region of the latest contraction (RLC). However, the RLC is not identified routinely to guide lead implantation to the coronary venous system (CVS). The aim of this study was: (i) to develop a software over-imposing CVS-anatomy on parametric images of left ventricular dyssynchrony in a 3D-format obtained from computed tomography (CT) and cardiac magnetic resonance imaging (MRI); and (ii) to apply this 3D-software for analysing the possible correlation between functional/ clinical improvement and the distance between final implantation site (FIS) and RLC. METHODS AND RESULTS: In 20 CHF-patients (11 men, 65.6 +/- 6.8 y, ejection fraction (EF): 27.5 +/- 6.1%) CRT-leads were implanted; follow-up included echocardiographic and exercise evaluation. The OIS and the FIS were noted on 3D-registrations and the distances OIS-RLC and FIS-RLC measured.The target vessel was reached in 14 cases. NYHA class and EF improved significantly with a low rate of non-responders of 3 (15%) (EF) and 4 (20%) (NYHA). Image registration was possible in all patients. Post-process 3D-analysis revealed no correlation between the distance FIS-RLC and functional or echocardiographic improvements.There was a trend towards a shorter distance FIS-RLC in patients classified as responders (EF). NYHA class improved significantly better in patients with target vessel implantation. CONCLUSIONS: Registration of CT/MRI-images enables efforts to reach the RLC by preoperative identification of corresponding veins. Larger randomized trials must define the definite therapeutic benefit.


Assuntos
Estimulação Cardíaca Artificial/métodos , Vasos Coronários/patologia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Contração Miocárdica , Marca-Passo Artificial , Tomografia Computadorizada por Raios X , Idoso , Vasos Coronários/fisiopatologia , Ecocardiografia Doppler/métodos , Feminino , Sistema de Condução Cardíaco/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
8.
J Am Coll Cardiol ; 55(5): 454-9, 2010 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-20117459

RESUMO

OBJECTIVES: This study sought to characterize the impact of hemodialysis (HD)-induced release of hemoglobin on the bioavailability of nitric oxide (NO) and endothelial function. BACKGROUND: Patients on chronic HD suffer from endothelial dysfunction and a massively increased risk for cardiovascular events. Although dialysis-dependent and -independent factors are discussed, the exact mechanisms are not fully understood. METHODS: In 14 HD patients (56+/-15 years of age), endothelial function was determined by measuring flow-mediated dilation (FMD) of the brachial artery using high-resolution ultrasound before and after treatment. The NO consumption activity of plasma isolated from patients before and after hemodialysis was studied with an NO-sensitive electrode. RESULTS: HD impaired FMD (3.5+/-2.6% to 1.7+/-1.4%, p=0.04) without affecting brachial artery diameter (4.7+/-0.6 mm vs. 4.4+/-0.9 mm, p=0.27). This was accompanied by an increase in cell-free plasma hemoglobin (196+/-43 mg/l to 285+/-109 mg/l, p=0.01), which led to a decrease in the bioavailability of free NO by more than 70%. Oxidation of the released plasma ferrous hemoglobin prevented the consumption of NO. The amount of decompartmentalized hemoglobin after HD correlated inversely with the change in FMD (r=-0.65, p=0.041). CONCLUSIONS: Our data support a role of HD-induced release of hemoglobin in the pathogenesis of endothelial dysfunction in patients with end-stage renal disease. Approaches that oxidize free plasma hemoglobin may restore NO bioavailability and may have potential beneficial effects on vascular function. (Influence of Hemodialysis on Endothel-Depending Dilatation of Peripheral Arteries; NCT00764192).


Assuntos
Doenças Cardiovasculares/etiologia , Endotélio Vascular/fisiopatologia , Hemoglobinas/metabolismo , Falência Renal Crônica/fisiopatologia , Óxido Nítrico/sangue , Diálise Renal/efeitos adversos , Adulto , Idoso , Artéria Braquial/fisiopatologia , Feminino , Hemólise , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/metabolismo , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Vasodilatação
9.
Clin Res Cardiol ; 99(5): 293-300, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20151141

RESUMO

OBJECTIVES: We sought to determine whether the thickness of the non-contrast-enhanced myocardial rim (RIM) predicts recovery of territorial myocardial function after revascularization in chronic ischemic cardiomyopathy (ICM). BACKGROUND: Non-contrast-enhanced dysfunctional myocardium at late gadolinium-enhanced CMR depicts the presence of viable myocardium. METHODS: In 29 patients (65 +/- 8 years) with ICM (EF 33 +/- 10), ceCMR and cine images were acquired 5 +/- 10 days before revascularization. Cine images were repeated after 6 months. Regional wall thickness, wall thickening and RIM were determined in each of 12 segments per short-axis slice (4-8/patient), which were assigned to the respective supplying coronary artery (LAD, LCX and RCA). A threshold for normal wall-thickening was derived from a control group (n = 14; 52 +/- 17 years). Functional improvement at follow-up was defined as wall thickening >2 mm. RESULTS: Of the 1,896 analyzed segments, 655 segments showed severe dysfunction. At follow-up, 307 segments demonstrated functional improvement. The RIM differed between segments with and without improvement (6.6 +/- 2.4 mm vs. 2.8 +/- 2.0 mm; p < 0.0001). The area under the receiver operator characteristic (ROC) for predicting overall functional recovery was 0.91 (95%, CI 0.88-0.93, p < 0.001). A RIM of 4.0 mm predicted functional recovery after revascularization of the supplying coronary artery with a sensitivity and a specificity of 88 and 82% for the LAD, 96 and 86% for the RCA and 88 and 83% for the LCX, respectively. CONCLUSION: RIM may be a useful marker for predicting territorial functional recovery after revascularization in patients with chronic ICM.


Assuntos
Gadolínio DTPA , Interpretação de Imagem Assistida por Computador/métodos , Imagem Cinética por Ressonância Magnética/métodos , Isquemia Miocárdica/patologia , Miocárdio/patologia , Doença Crônica , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade , Resultado do Tratamento
10.
Cardiovasc Intervent Radiol ; 33(2): 389-93, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19657692

RESUMO

We report the case of a man with an uncommon anomaly of the origin and course of the left coronary artery. Clinical, coronary angiography, magnetic resonance imaging, and multislice computed tomography findings of this intermittently symptomatic 49 year-old patient with the rare anomaly of his left coronary artery stemming from the right sinus of Valsalva and taking an interarterial and intraseptal course are presented. The diagnostic value of the different imaging modalities is discussed.


Assuntos
Anomalias dos Vasos Coronários/diagnóstico , Angiografia por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico , Intensificação de Imagem Radiográfica , Seio Aórtico/anormalidades , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Angiografia Coronária/métodos , Ponte de Artéria Coronária/métodos , Anomalias dos Vasos Coronários/complicações , Anomalias dos Vasos Coronários/cirurgia , Eletrocardiografia , Seguimentos , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/cirurgia , Doenças Raras , Medição de Risco , Índice de Gravidade de Doença , Seio Aórtico/diagnóstico por imagem , Resultado do Tratamento
11.
Eur J Echocardiogr ; 11(1): 1-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19755469

RESUMO

AIMS: Our aim was to assess the feasibility and safety of real-time (RT) three-dimensional (3D) transoesophageal echocardiography (TEE) for guiding transcatheter closure of interatrial communications and to evaluate its additional benefit over conventional 2D TEE in reducing radiation exposure for the patient. METHODS AND RESULTS: Twenty-five patients undergoing device closure of their interatrial defect had the procedure guided by fluoroscopy, 2D TEE, and RT 3D TEE. We retrospectively compared this group with a historical control group in which interventional guidance was performed using fluoroscopy and 2D TEE alone. The application of RT 3D TEE allowed safe device deployment in all patients without any complications, resulting in a reduction of mean fluoroscopy time (10 +/- 6 to 6 +/- 4 min, P < 0.01), mean dose area product (DAP) (964 +/- 628 to 535 +/- 464 cGy cm(2), P < 0.01), and mean DAP per individual body surface area (494 +/- 317 to 273 +/- 221 cGy cm(2)/m(2), P < 0.01). CONCLUSION: RT 3D TEE as an adjunct to 2D TEE is a feasible and safe tool to guide transcatheter device closure of interatrial communications, resulting in a reduction of radiation exposure. These data indicate that RT 3D TEE can be used to safely monitor interatrial defect closure in clinical routine.


Assuntos
Cateterismo Cardíaco , Ecocardiografia Tridimensional/métodos , Ecocardiografia Transesofagiana/métodos , Átrios do Coração/diagnóstico por imagem , Comunicação Interatrial/cirurgia , Dispositivo para Oclusão Septal , Adulto , Estudos de Coortes , Ecocardiografia Tridimensional/efeitos adversos , Ecocardiografia Transesofagiana/efeitos adversos , Estudos de Viabilidade , Feminino , Fluoroscopia , Forame Oval Patente/cirurgia , Átrios do Coração/efeitos da radiação , Átrios do Coração/cirurgia , Comunicação Interatrial/diagnóstico por imagem , Humanos , Masculino , Doses de Radiação , Estudos Retrospectivos , Fatores de Tempo
14.
Eur Heart J ; 30(16): 2054-61, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19429630

RESUMO

AIMS: Fetuin-A has been identified as a potent circulating inhibitor of ectopic calcification. We investigated the relationship between baseline fetuin-A serum levels and the rate of progression of aortic valve calcification (AVC) in non-dialyzed patients with aortic valve disease (AVD). METHODS AND RESULTS: Seventy-seven patients (mean age 70 +/- 8 years) with echocardiographically proven AVD were collected. In all patients, serum fetuin-A levels, creatinine, calcium, lipid parameters, and C-reactive protein were measured at baseline. For quantification of AVC progression, all patients underwent multislice spiral computed tomography examinations at baseline and after a mean follow-up of 12.6 +/- 1.4 months (range 7-18 months). In a multifactorial analysis of covariance including fetuin-A levels, baseline AVC score, the covariables sex, age, body mass index, C-reactive protein, glomerular filtration rate, serum lipids, diabetes, smoking status, and hypertension, only serum fetuin-A levels significantly predict the progression of AVC (P < 0.001). Post hoc analysis demonstrated that patients with baseline fetuin-A levels lower than the median of the cohort (0.72 g/L) showed a significantly higher increase of AVC scores (34.6 +/- 31.4%) than patients with fetuin-A levels larger than the median (10.0 +/- 11.2%, P < 0.001) despite comparable baseline AVC scores. In addition, fetuin-A levels were associated with major adverse clinical events (MACE; P = 0.03). CONCLUSION: Serum levels of the calcification inhibitor fetuin-A are associated with the progression of AVC and MACE, independent of the renal function and inflammation.


Assuntos
Doenças da Aorta/diagnóstico , Valva Aórtica , Proteínas Sanguíneas/metabolismo , Calcinose/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Sanguíneas/deficiência , Angiografia Coronária , Progressão da Doença , Ecocardiografia , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Tomografia Computadorizada Espiral , alfa-2-Glicoproteína-HS
15.
Thromb Haemost ; 101(4): 706-13, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19350115

RESUMO

Matrix-Gla Protein (MGP) is a vitamin K-dependent protein acting as a local inhibitor of vascular calcification. Vitamin K-antagonists (oral anticoagulant; OAC) inhibit the activation of MGP by blocking vitamin K-metabolism. The aim of this study was to investigate the effect of long-term OAC treatment on circulating MGP levels in humans and on MGP expression in mice. Additionally, we tested the association between circulating inactive MGP (ucMGP) levels and the presence and severity of AVC in patients with aortic valve disease (AVD). We analysed circulating ucMGP levels in 191 consecutive patients with echocardiographically proven calcific AVD and 35 control subjects. The extent of AVC in the patients was assessed by multislice spiral computed tomography. Circulating ucMGP levels were significantly lower in patients with AVD (348.6 +/- 123.1 nM) compared to the control group (571.6 +/- 153.9 nM, p < 0.001). Testing the effect of coumarin in mice revealed that also the mRNA expression of MGP in the aorta was downregulated. Multifactorial analysis revealed a significant effect of glomerular filtration rate and long-term OAC therapy on circulating ucMGP levels in the patient group. Subsequently, patients on long-term OAC had significantly increased AVC scores. In conclusion, patients with calcific AVD had significantly lower levels of circulating ucMGP as compared to a reference population, free of coronary and valvular calcifications. In addition, our data suggest that OAC treatment may decrease local expression of MGP, resulting in decreased circulating MGP levels and subsequently increased aortic valve calcifications as an adverse side effect.


Assuntos
Anticoagulantes/efeitos adversos , Valva Aórtica/efeitos dos fármacos , Calcinose/induzido quimicamente , Proteínas de Ligação ao Cálcio/sangue , Proteínas da Matriz Extracelular/sangue , Doenças das Valvas Cardíacas/induzido quimicamente , Varfarina/efeitos adversos , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticoagulantes/administração & dosagem , Aorta/efeitos dos fármacos , Aorta/metabolismo , Valva Aórtica/diagnóstico por imagem , Biomarcadores/sangue , Calcinose/sangue , Calcinose/diagnóstico , Estudos de Casos e Controles , Estudos Transversais , Modelos Animais de Doenças , Regulação para Baixo , Ecocardiografia , Feminino , Taxa de Filtração Glomerular , Doenças das Valvas Cardíacas/sangue , Doenças das Valvas Cardíacas/diagnóstico , Humanos , Masculino , Camundongos , Camundongos Endogâmicos DBA , Pessoa de Meia-Idade , Osteopontina/genética , Prognóstico , RNA Mensageiro/metabolismo , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Tomografia Computadorizada Espiral , Vitamina K/antagonistas & inibidores , Vitamina K/sangue , Varfarina/administração & dosagem , Proteína de Matriz Gla
16.
Eur Radiol ; 19(9): 2136-46, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19373470

RESUMO

Gadobenate (Gd-BOPTA), injected at a dose of 0.1 mmol/kg body weight, was compared with gadopentetate (Gd-DTPA), injected at a dose of 0.2 mmol/kg body weight, for delineation of myocardial infarction interindividually in two groups of 26 patients each. Delayed enhancement images were assessed subjectively for image quality, and measured for regional T1 values before, 3 min after and 25 min after the injection of each contrast agent. In the 26 patients who received Gd-BOPTA, T1 values of remote myocardium were 1,070 +/- 125 ms, 358 +/- 78 ms and 562 +/- 108 ms before, 3 min after and 25 min after injection, respectively. Infarcted myocardium values were 1,097 +/- 148 ms, 246 +/- 68 ms and 373 +/- 84 ms and left ventricular blood pool 1,238 +/- 95 ms, 194 +/- 47 ms and 373 +/- 72 ms. In the 26 patients who received Gd-DTPA, T1 values were 1,087 +/- 96 ms, 325 +/- 60 ms and 555 +/- 108 ms for remote myocardium; 1,134 +/- 109, 210 +/- 43 ms and 304 +/- 57 ms for infarcted myocardium; and 1,258 +/- 104 ms, 166 +/- 27 ms and 351 +/- 73 ms for left ventricular blood pool. Delayed enhancement image quality showing myocardial infarction was rated good (54%) and excellent (46%) after Gd-BOPTA, and good (58%) and excellent (42%) after Gd-DTPA (no significant differences). A single dose of Gd-BOPTA compared with a double dose of Gd-DTPA causes similar changes of T1 values in infarcted and remote myocardium and provides fairly similar contrast between infarcted and remote myocardium (0.64 +/- 14 versus 0.71 +/- 11) and slightly higher contrast between left ventricular blood and infarcted myocardium (0.22 +/- 17 versus 0.14 +/- 6; p < 0.05). Administration of 0.1 mmol/kg body weight Gd-BOPTA can provide similar late enhancement images compared with the standard 0.2 mmol/kg body weight dose of Gd-DTPA due to the higher T1 relaxivity associated with the former.


Assuntos
Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Meglumina/análogos & derivados , Isquemia Miocárdica/complicações , Isquemia Miocárdica/diagnóstico , Miocárdio Atordoado/complicações , Miocárdio Atordoado/diagnóstico , Compostos Organometálicos , Adulto , Idoso , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Eur Heart J ; 30(12): 1467-76, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19351689

RESUMO

AIMS: To evaluate deformation parameters of an endocardial, mid-myocardial, and epicardial myocardial layer in different transmurality of myocardial infarction and assess whether layer-specific deformation analysis allows definition of infarct transmurality. METHODS AND RESULTS: Fifty-six patients (mean age 55 +/- 9 years, 38 men) with chronic ischaemic left ventricular (LV) dysfunction underwent two-dimensional echocardiography and contrast-enhanced magnetic resonance imaging (ceMRI). The extent of myocardial infarction was determined as relative amount of hyperenhancement by ceMRI in a 16-segment LV model (0%, no infarction; 1-50%, non-transmural infarction; 51-100%, transmural infarction). On the basis of two-dimensional echocardiographic parasternal short-axis views peak systolic circumferential strain was determined for the total wall thickness and for each of three myocardial layers (endocardial, mid-myocardial, and epicardial) using an automatic frame-by-frame tracking system of acoustic echocardiographic markers (EchoPAC, GE Ultrasound). In non-transmural infarction impairment of circumferential strain was greater in the endocardial than the epicardial layer, relative reduction compared with control segments, 45% vs. 28% (P < 0.001), respectively. In transmural infarction additional impairment of circumferential strain was greater in the epicardial than the endocardial layer, relative reduction compared with non-transmural infarction 29% vs. 7% (P < 0.001), respectively. Endocardial layer circumferential strain allowed distinction of non-transmural vs. no infarction with higher accuracy than total wall thickness strain [area under the curve (AUC) 0.842 vs. 0.774, respectively, P = 0.001]. Epicardial layer circumferential strain allowed distinction of transmural from non-transmural infarction with higher accuracy than total wall thickness strain (AUC 0.819 vs. 0.762, respectively, P = 0.005). CONCLUSION: Non-transmural infarction results in greater functional impairment of the endocardial than of the epicardial myocardial layer. In transmural infarction both layers are affected similarly compared with controls. A layer-specific analysis of myocardial deformation allows accurate discrimination between different transmurality categories of myocardial infarction.


Assuntos
Endocárdio/fisiopatologia , Infarto do Miocárdio/fisiopatologia , Pericárdio/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia , Meios de Contraste , Angiografia Coronária , Ecocardiografia , Feminino , Humanos , Aumento da Imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico , Imagem Corporal Total
18.
Clin Res Cardiol ; 98(5): 319-24, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19262976

RESUMO

BACKGROUND: In clinical routine, rapid infarct sizing techniques are warranted, as objective and precise infarct sizing is important for clinical decision-making. Accurate and objective measures of relative infarct size (rIS) using contrast-enhanced cardiac magnetic resonance (ceCMR) have been extensively demonstrated in experimental animals, but less in humans. The aim of this study was therefore to quantify rIS assessed by ceCMR in patients with chronic myocardial infarction using semi-automatic quantitation techniques. METHODS: A total of 62 patients (mean age 66 +/- 9 years) with ischemic cardiomyopathy (EF 24 +/- 8%) underwent ceCMR for viability testing. rIS was obtained by two time-saving semi-automatic thresholding methods based on: (1) visual definition of a single signal intensity cutoff value (VISUAL) and (2) the full-width-at-half-maximum technique (FWHM). Results were compared to manual tracing (MANUAL) as the reference standard. RESULTS: VISUAL showed better agreement [r = 0.99; intraclass correlation coefficient (ICC) = 0.98, limits of agreement +/-3.2%] to MANUAL than the FWHM technique (r = 0.77, ICC = 0.76, limits of agreement +/-12%). Infarct sizing using MANUAL was twice as time-consuming (3.1 +/- 0.2 min) compared to VISUAL (1.6 +/- 0.1 min) or FWHM (1.6 +/- 0.2 min). CONCLUSIONS: Visual estimation of signal intensity cutoff values allows rapid and accurate determination of rIS in patients with chronic myocardial infarction using ceCMR and is superior to the FWHM technique.


Assuntos
Cardiomiopatias/diagnóstico , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Infarto do Miocárdio/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico , Idoso , Cardiomiopatias/complicações , Meios de Contraste , Feminino , Humanos , Masculino , Infarto do Miocárdio/complicações , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo , Disfunção Ventricular Esquerda/complicações
19.
Eur J Echocardiogr ; 10(3): 341-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19211569

RESUMO

The growing need for less invasive therapies of cardiac disease creates the necessity for improved imaging guidance. Although two-dimensional transthoracic and transoesophageal echocardiography (TEE) have been shown to be essential tools for planning and execution of cardiac interventions, the benefit of three-dimensional TEE for the guidance of interventional procedures still needs to be evaluated. This review aims to describe our first experiences with real-time (RT) three-dimensional TEE for the guidance of percutaneous non-coronary interventions in the catheter laboratory. We used a matrix array TEE probe capable of generating three-dimensional images of cardiac structures in RT. We applied this innovative technique to monitor atrial septal defects or patent foramen ovale closures, valve procedures such as mitral and aortic valve interventions, and electrophysiological procedures. Our first experience using RT three-dimensional TEE for the guidance of percutaneous cardiac interventions in the catheter laboratory demonstrates that this technique is feasible to guide interventions, providing fast and complete information about the underlying pathomorphology, improving spatial orientation, and additionally allowing the online monitoring of the procedure. These benefits may accelerate the learning curve and improve confidence of the interventional cardiologist in order to increase safety, accuracy, and efficacy of interventional cardiac procedures.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Ecocardiografia Tridimensional/métodos , Ecocardiografia Transesofagiana/métodos , Ultrassonografia de Intervenção/métodos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Comunicação Interatrial/diagnóstico por imagem , Comunicação Interatrial/cirurgia , Humanos , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Fatores de Tempo
20.
Coron Artery Dis ; 20(1): 21-6, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19008764

RESUMO

BACKGROUND: Myocardial deformation imaging and contrast-enhanced cardiac magnetic resonance imaging (ceMRI) have been used to define myocardial viability in ischemic left ventricular dysfunction. This study evaluated the incremental predictive value of an integrated analysis of function and tissue structure for functional improvement after revascularization therapy. METHODS: In 59 patients with ischemic left ventricular dysfunction, myocardial viability was defined by pixel-tracking-derived myocardial deformation imaging and ceMRI to predict recovery of function at 9+/-2 months follow-up after revascularization. For each left ventricular segment in a 16-segment model, peak systolic radial strain was determined from parasternal two-dimensional echocardiographic views using an automatic frame-by-frame tracking system of natural acoustic echocardiographic markers, and extent of hyperenhancement using ceMRI. Five categories were generated for each parameter, allowing subsequent combination. The predictive power for segmental improvement in function was determined for each of the modalities as well as the combination of both. RESULTS: From 512 dysfunctional segments at baseline, 251 segments (49%) demonstrated functional recovery. The accuracy to predict functional recovery was area under curve (AUC)=0.846 for peak systolic radial strain and AUC=0.834 for extent of hyperenhancement. A combination of both parameters improved the predictive accuracy compared with hyperenhancement alone, AUC=0.861, P value of less than 0.001. In sequential Cox models, the predictive power for segmental functional recovery of extent of hyperenhancement alone (chi model 171.0, P<0.001), or peak systolic radial strain alone (chi model 205.9, P<0.001), was strengthened by a combination of both parameters (chi model 248.5, P<0.001). The advantage of image integration was particularly strong in those segments with intermediate degree of late enhancement (DeltaAUC=0.065, P<0.001). CONCLUSION: Integration of advanced information on myocardial function using deformation imaging and findings on myocardial tissue structure increases the accuracy to identify reversible myocardial dysfunction.


Assuntos
Meios de Contraste , Ventrículos do Coração/patologia , Imageamento por Ressonância Magnética , Isquemia Miocárdica/patologia , Revascularização Miocárdica , Miocárdio/patologia , Disfunção Ventricular Esquerda/patologia , Idoso , Área Sob a Curva , Ecocardiografia/métodos , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Aumento da Imagem , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/terapia , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Curva ROC , Recuperação de Função Fisiológica , Volume Sistólico , Fatores de Tempo , Sobrevivência de Tecidos , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/terapia
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