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1.
Rev Med Suisse ; 9(398): 1688-93, 2013 Sep 18.
Artigo em Francês | MEDLINE | ID: mdl-24164020

RESUMO

The results of several large multicenter CMR studies were reported in 2012, thus, constantly corroborating the evidence on CMR performance. In this review, we present results of the MR-IMPACT programme and the CE-MARC study, which demonstrated the superiority of perfusion-CMR over gated SPECT for the workup of suspected CAD, the currently available data from the European CMR registry, comprising almost 30,000 patients from 57 participating centers in 15 European countries, and finally, the results of the Advisa-MRI study, which documented the safety of a MRI-compatible pacemaker system. These large trials and others set the basis for the recommendations in the new European guidelines on heart failure to use CMR as a first line method if echocardiographic quality is inadequate or the etiology of heart failure is unclear.


Assuntos
Cardiopatias/diagnóstico , Imagem Cinética por Ressonância Magnética , Estudos Multicêntricos como Assunto , Europa (Continente) , Cardiopatias/etiologia , Humanos , Sistema de Registros
2.
Rev Med Suisse ; 7(277): 8-10, 12-5, 2011 Jan 12.
Artigo em Francês | MEDLINE | ID: mdl-21309167

RESUMO

The present review provides a selected choice of clinical research in the field of interventional cardiology, electrophysiology and cardiac imaging. We also focused on the new guidelines published by the European society of cardiology in 2010 (revascularization, atrial fibrillation and device therapy in heart failure).


Assuntos
Cardiologia/tendências , Ecocardiografia Doppler , Técnicas Eletrofisiológicas Cardíacas , Cardiopatias/diagnóstico , Humanos , Revascularização Miocárdica
3.
Rev Med Suisse ; 4(159): 1304-6, 1308-10, 2008 May 28.
Artigo em Francês | MEDLINE | ID: mdl-18592721

RESUMO

Echocardiography is the preferred initial test to assess cardiac morphology and ventricular function. Cardiac MRI enables an optimal visualisation of heart muscle without contrast injection, and precise measurement of the ventricular volumes and systolic function. It is therefore an ideal test for patients with poor echocardiographic windows or for the specific evaluation of right heart chambers. Heart CT also remarkably images heart muscle and precisely measures ventricular systolic function after intravenous injection of iodinated contrast. Coronary CT may also, in selected cases, avoid the need for diagnostic coronary angiography. Although very accurate, these imaging modalities are expensive and may be contra-indicated for a particular patient. Their use in clinical practice has to follow the accepted guidelines.


Assuntos
Diagnóstico por Imagem , Coração/diagnóstico por imagem , Miocárdio/patologia , Humanos , Radiografia
4.
Rev Med Suisse ; 4(159): 1311-2, 1314-7, 2008 May 28.
Artigo em Francês | MEDLINE | ID: mdl-18592722

RESUMO

The non-invasive evaluation of myocardial ischemia is a priority in cardiology. The preferred initial non-invasive test is exercise ECG, because of its high accessibility and its low cost. Stress radionuclide myocardial perfusion imaging or stress echocardiography are now routinely performed, and new non-invasive techniques such as perfusion-MRI, dobutamine stress-MRI or 82rubidium perfusion PET have recently gained acceptance in clinical practice. In the same time, an increasing attention has been accorded to the concept of myocardial viability in the decisional processes in case of ischemic heart failure. In this indication, MRI with late enhancement after intravenous injection of gadolinium and 18F-FDG PET showed an excellent diagnostic accuracy. This article will present these new imaging modalities and their accepted indications.


Assuntos
Diagnóstico por Imagem/métodos , Isquemia Miocárdica/diagnóstico , Humanos
5.
Rev Med Suisse ; 4(159): 1318, 1320-4, 2008 May 28.
Artigo em Francês | MEDLINE | ID: mdl-18592723

RESUMO

Echocardiography is the preferred initial noninvasive test to assess heart muscle and heart valves. Cardiac MRI has a unique capacity to directly characterise myocardial tissue with specific imaging sequences and late enhancement pattern after gadolinium injection, and has a specific role in the diagnosis of cardiomyopathies. In valvular heart diseases, cardiac MRI precisely measures the severity of aortic or pulmonary regurgitation. In pericardial heart diseases, and specifically when constrictive pericarditis is suspected, cardiac MRI and/or CT are useful to look for pericardial thickening. Cardiac CT and MRI are very rapidly developing techniques in cardiology; the use of these expensive techniques must follow the currently accepted indications in order to be integrated in a rational diagnosis process in clinical practice.


Assuntos
Cardiopatias/diagnóstico , Imagem Cinética por Ressonância Magnética , Tomografia Computadorizada por Raios X , Humanos
6.
Rev Med Suisse ; 3(113): 1383-4, 1386-90, 2007 May 30.
Artigo em Francês | MEDLINE | ID: mdl-17645052

RESUMO

The beneficial effect of cardiac resynchronization therapy has been demonstrated in large clinical trials. However, on an individual basis 20% to 30% of patients receiving this therapy will lack improvement or even deteriorate. A better selection of patients to predict response to cardiac resynchronization therapy is therefore needed. Echocardiographic studies have clearly demonstrated that the presence of intra-ventricular dyssynchrony is an important factor determining response to resynchronization therapy, whereas interventricular dyssynchrony appears to be of less importance. Of the different echocardiographic approaches aimed at prediction of response to resynchronization therapy, literature suggests that tissue Doppler imaging may represent the best method. Ongoing research trials will further define the role of other new bi- or three-dimensional echocardiographic tools in the clinical management of patients with heart failure.


Assuntos
Arritmias Cardíacas/diagnóstico por imagem , Arritmias Cardíacas/terapia , Estimulação Cardíaca Artificial , Ventrículos do Coração , Humanos , Ultrassonografia
7.
Praxis (Bern 1994) ; 95(24): 977-81, 2006 Jun 14.
Artigo em Francês | MEDLINE | ID: mdl-16802507

RESUMO

Systemic amyloidosis with cardiac involvement may clinically be suspected in the presence of heart failure or arrhythmia of unknown origin. Herein two cases of cardiac amyloidosis are described with a clinical presentation of heart failure refractory to usual treatment. The key role of echocardiography in the diagnosis and prognosis evaluation of cardiac amyloidosis is discussed. A treatment targeted against the generation of amyloid fibril should ideally be initiated before apparition of heart failure.


Assuntos
Amiloidose/diagnóstico por imagem , Cardiomiopatias/diagnóstico por imagem , Ecocardiografia , Idoso , Amiloidose/patologia , Amiloidose/terapia , Biópsia , Cardiomiopatias/patologia , Cardiomiopatias/terapia , Diagnóstico Diferencial , Eletrocardiografia , Evolução Fatal , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/terapia , Humanos , Pessoa de Meia-Idade , Prognóstico , Tela Subcutânea/patologia
8.
Rev Med Suisse ; 1(21): 1432-7, 2005 May 25.
Artigo em Francês | MEDLINE | ID: mdl-15997982

RESUMO

Terminal heart failure can be the cause or the result of major dysfunctions of the organisms. Although, the outcome of the natural history is the same in both situations, it is of prime importance to differentiate the two, as only heart failure as the primary cause allows for successful mechanical circulatory support as bridge to transplantation or towards recovery. Various objective parameters allow for the establishment of the diagnosis of terminal heart failure despite optimal medical treatment. A cardiac index <2.0 l/min, and a mixed venous oxygen saturation <60%, in combination with progressive renal failure, should trigger a diagnostic work-up in order to identify cardiac defects that can be corrected or to list the patient for transplantation with/without mechanical circulatory support.


Assuntos
Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/cirurgia , Transplante de Coração , Coração Artificial , Circulação Assistida , Humanos , Oxigênio/sangue , Prognóstico , Insuficiência Renal/etiologia
9.
Neuromuscul Disord ; 15(4): 293-8, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15792868

RESUMO

A family with several cases of severe cardiomyopathy and moderate myopathy is described, affecting two brothers and their cousin as well as their mothers. One boy died of sudden cardiac arrest at 17 years of age. The two brothers were treated with an implantable defibrillator and their mother died suddenly at 40 years of age. Muscle biopsy in males showed vacuolar myopathy in two cases, and no abnormality on standard staining in the third case. Cardiac biopsies showed hypertrophic and vacuolated fibres. Complete absence of LAMP-2 was demonstrated by immunohistochemistry on the vacuolated skeletal and cardiac muscle, but also on the morphologically normal skeletal muscle. Sequencing of LAMP-2 gene showed a novel S157X mutation in exon 4. Danon disease is a rare and potentially lethal cause of hypertrophic cardiomyopathy. Diagnosis can be made by immunohistochemistry performed on cardiac or muscle biopsy, and confirmed by genetic analysis, which also allows for easy family screening and counselling.


Assuntos
Antígenos CD/genética , Cardiomiopatias/genética , Saúde da Família , Doenças Musculares/genética , Mutação , Adolescente , Adulto , Biópsia/métodos , Cardiomiopatias/patologia , Cardiomiopatias/fisiopatologia , Criança , Análise Mutacional de DNA , Feminino , Humanos , Proteínas de Membrana Lisossomal , Masculino , Microscopia Eletrônica de Transmissão/métodos , Músculo Esquelético/patologia , Músculo Esquelético/ultraestrutura , Doenças Musculares/patologia , Doenças Musculares/fisiopatologia , Miocárdio/patologia , Miocárdio/ultraestrutura , Serina/genética , Coloração e Rotulagem/métodos
10.
Eur J Echocardiogr ; 5(6): 422-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15556817

RESUMO

AIMS: Mitral valve prolapse is a common source of severe mitral regurgitation in Western countries. Three-dimensional echocardiography can provide views of the entire valve, allowing a complete assessment of the valve leaflets and commissures. It has the potential to precisely locate and quantify mitral valve prolapse. METHODS AND RESULTS: Between January 1997 and December 2000, 91 patients with severe mitral regurgitation due to mitral valve prolapse underwent a transesophageal echocardiography with three-dimensional reconstruction of the mitral valve as part of their pre-operative work-up. The location and extent of the prolapse by echo was compared to the surgical status. The volume of prolapsing leaflet was calculated and compared to the volume of resected tissue whenever a repair was attempted. There was an excellent correspondence between the echographic localization of the prolapse and surgical inspection, and between the volume of prolapsing and surgically resected tissue (r=0.94, p<0.0001). CONCLUSIONS: In patients with severe mitral regurgitation due to mitral valve prolapse, 3D echo allowed a precise localization and an accurate quantification of the prolapsing portion of the leaflets. This technique can provide refinements in the surgical planning of mitral valve repair and in the selection of candidates for this intervention.


Assuntos
Ecocardiografia Tridimensional/métodos , Prolapso da Valva Mitral/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
12.
Am J Cardiol ; 84(9): 1101-3, A10, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10569676

RESUMO

In this study, which included 56 patients with aortic stenosis, the predictive value of the fractional shortening velocity ratio was evaluated. This Doppler index allowed detection of significant aortic stenosis (0.53 cm2/m2), with a positive predictive value of 93% and a negative predictive value of 92% for a cutoff value of 0.8.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo/fisiologia , Ecocardiografia Doppler em Cores , Ecocardiografia , Idoso , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Estudos Prospectivos , Sensibilidade e Especificidade , Função Ventricular Esquerda/fisiologia
14.
Eur Heart J ; 20(14): 1044-50, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10381856

RESUMO

AIMS: Atrioventricular synchronous pacing exerts beneficial effects, including reduction of left ventricular outflow tract gradients, in patients with hypertrophic obstructive cardiomyopathy. The Pacing in Cardiomyopathy study was initiated to explore the effects of pacing in a double-blind randomized crossover fashion. The aims were to ascertain the beneficial effects of pacing in a controlled study and to rule out a placebo effect by pacing. This paper deals with the outcome of pacing on quality of life during 1 year of follow-up. METHODS: Quality of life was evaluated with the Karolinska questionnaire, validated for patients paced for bradyarrhythmias and ischaemic heart disease. Drug-refractory patients with hypertrophic obstructive cardiomyopathy were recruited for the study and after a temporary pacing procedure implanted with permanent pacemakers. Patients were randomized to two study arms defining the sequence of pacemaker programming. In one arm the pacemaker was inactive, in the other active. After 3 months the pacemaker was reprogrammed to the alternate mode and a further 3 months followed. After this period subsequent pacemaker programming corresponded to the mode preferred by the patient. A last assessment was made 1 year after baseline examinations. RESULTS: Eighty patients completed the first crossover period and 75 completed the full 1 year of follow-up. Active pacing induced significant quality of life improvements, in the order of 9-44%, regardless of programming sequence. Discontinuation of pacing after a first active period resulted in the return of symptoms. Fourteen patients requested early reprogramming after having been programmed to inactive pacing after a first period of active pacing. Seventy-six patients preferred active pacing after the crossover period. A further 6 months of pacing induced progressive improvement in symptoms already favourably influenced. CONCLUSION: Atrioventricular synchronous pacing has a profound beneficial effect on most domains of quality of life in patients with hypertrophic obstructive cardiomyopathy refractory to drug treatment.


Assuntos
Estimulação Cardíaca Artificial , Cardiomiopatia Hipertrófica/terapia , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Europace ; 1(2): 77-84, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11233189

RESUMO

BACKGROUND: The therapeutic options for hypertrophic obstructive cardiomyopathy (HOCM) classically include medical treatment with beta-blockers and calcium antagonists or myectomy-myotomy as a surgical possibility for refractory cases. The observation that pacemaker activation of the heart in HOCM reduces the subaortic gradient is well known but less well investigated. METHODS: Eighty-three patients (33 female and 50 male) mean age 53 (18-82) years, with symptoms refractory to drug treatment and a resting gradient above 30 mmHg, who responded favourably to temporary pacing, were included in this prospective study and had a pacemaker (DDD) implanted. After an initial double-blind crossover phase of 6 months, patients were reinvestigated at 12 months and followed for a mean of 36 months. RESULTS: As observed during a screening investigation, the obstruction was significantly reduced from 72 +/- 35 mmHg to 29 +/- 24 mmHg (P < 0.01) when the pacemaker was on, while no major effect was seen during the sham phase. The effect was persistent at 1 year with a remaining resting gradient of 28 +/- 24 mmHg. In parallel, we documented an improvement in functional capacity, according to the NYHA classification and by quality of life analysis, and a significant improvement in dyspnoea and angina. Exercise on treadmill improved only in patients with reduced initial tolerance (< 8 min). During the mean follow-up of 36 months, 65 patients remained on pacing alone, with eight patients having additional AV-node ablation and five patients finally having surgery. CONCLUSION: This controlled multicentre study shows that pacemaker treatment is an option for HOCM patients; it is inoffensive and does not exclude alternative methods, but satisfies 79% of patients beyond 3 years.


Assuntos
Cardiomiopatia Hipertrófica/terapia , Marca-Passo Artificial , Adolescente , Adulto , Idoso , Método Duplo-Cego , Tolerância ao Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento , Obstrução do Fluxo Ventricular Externo/fisiopatologia
16.
Int J Card Imaging ; 14(4): 271-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9934615

RESUMO

Assessment of right ventricular volume and function is important in many clinical settings involving heart or lung disease. However, the complexity of the right ventricular anatomy has prevented accurate volume determination by two-dimensional echocardiography. In the present study, 5 models incorporating standard echocardiographic views, were used to determine right ventricular volume in 10 human subjects. Two models were contingent on the true crescentic appearance of the right ventricle, whereas the remaining 3 calculated the right ventricular volume as a pyramid, an ellipsoid or other tapering geometrical figures, respectively. Subsequently, echocardiographic right ventricular volumes were compared to magnetic resonance imaging derived volumes. Correlation analysis and agreement measurement between the echocardiographic and magnetic resonance end-diastolic volume were performed in 10 out of 10 subjects and in 9 out of 10 subjects for the end-systolic volume. The 2 crescentic models resulted in the most reliable estimation of right ventricular volume. Those findings suggest that models based on right ventricular anatomical landmarks are feasible and should be preferred in echocardiographic studies.


Assuntos
Ecocardiografia , Imageamento por Ressonância Magnética , Função Ventricular Direita/fisiologia , Adulto , Humanos , Processamento de Imagem Assistida por Computador , Modelos Cardiovasculares , Modelos Teóricos
17.
Eur Heart J ; 18(8): 1249-56, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9458416

RESUMO

BACKGROUND: Uncontrolled studies have shown that short atrioventricular delay dual chamber pacing reduces outflow tract obstruction in hypertrophic obstructive cardiomyopathy. Although the exact mechanism of this beneficial effect is unclear, this seems a promising potential new treatment for hypertrophic obstructive cardiomyopathy. METHOD: In order to evaluate the impact of pacing therapy, were performed a randomized multicentre double-blind cross-over (pacemaker activated vs non activated) study to investigate modification of echocardiography, exercise tolerance, angina, dyspnoea and quality of life in 83 patients with a mean age of 53 (range 22-87) years with symptoms refractory or intolerant to classical drug treatment. RESULTS: After 12 weeks of activated or inactivated pacing, independent of which phase was first, the pressure gradient fell from 59 +/- 36 mmHg to 30 +/- 25 mmHg (P < 0.001) with active pacing. Exercise tolerance improved by 21% in those patients who at baseline tolerated less than 10 min of Bruce protocol; symptoms of dyspnoea and angina also improved significantly from NYHA class 2.4 to 1.4 and 1.0 to 0.4, respectively (P < 0.007). Quality of life assessment with a validated questionnaire objectivated the subjective improvement. CONCLUSION: Pacemaker therapy is of clinical and haemodynamic benefit for patients with hypertrophic obstructive cardiomyopathy, left ventricular outflow gradient at rest over 30 mmHg who are symptomatic despite drug treatment.


Assuntos
Estimulação Cardíaca Artificial , Cardiomiopatia Hipertrófica/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Método Duplo-Cego , Tolerância ao Exercício , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Estatísticas não Paramétricas
18.
Pacing Clin Electrophysiol ; 20(6): 1673-81, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9227766

RESUMO

In order to assess the influence of right ventricular stimulation on LV contraction sequence in hypertrophic obstructive cardiomyopathy (HOCM), we performed a regional wall-motion analysis of the left ventricle by comparing normal His-Purkinje activation to pacing from the right ventricular apex. In 9 patients (5 males and 4 females, mean age 61 +/- 9 years) assessed after a mean pacing period of 12 weeks (range 7-24 weeks), AV sequential pacing induced a 52% reduction in maximal pressure gradient from 76 +/- 36 to 40 +/- 28 mmHg (P < 0.01) as determined by Doppler examination. Regional wall-motion analysis of the left ventricle was computed from digitized two-dimensional echocardiographic images by means of the area shrinking method. Pacing induced a significant reduction of total septal area shrinking from 25% +/- 17% to 12% +/- 17% (P < 0.005). A tendency toward paradoxical septal motion was observed in one patient only. The apex showed no significant variation. A 6% increase in area shrinking was observed at the posterior wall and lateral free wall, from 38% +/- 13% to 43% +/- 10% (P < 0.05). Pacing did not significantly alter the global ejection fraction. A direct correlation between the magnitude of subaortic pressure gradient reduction and that of septal motion changes was found in a majority of patients. In conclusion, dual chamber pacing reduces septal wall motion in patients with HOCM obstructive cardiomyopathy. This might be one of the mechanisms involved in the reduction of LV outflow tract obstruction.


Assuntos
Cardiomiopatia Hipertrófica/terapia , Contração Miocárdica/fisiologia , Marca-Passo Artificial , Estimulação Cardíaca Artificial/métodos , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/fisiopatologia , Ecocardiografia , Ecocardiografia Doppler , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Função Ventricular Esquerda/fisiologia , Função Ventricular Direita/fisiologia
19.
Eur J Cardiothorac Surg ; 11(5): 824-7, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9196295

RESUMO

OBJECTIVE: To define therapeutic strategy for management of patients with ischemic stroke due to a high probability of paradoxical embolism through a Patent Foramen Ovale (PFO). METHODS: Since 1988 all consecutive patients with cerebrovascular events and PFO from the Stroke Registry of our population-based primary-care center are prospectively studied and followed. Since 1992, among 118 patients with cryptogenic embolic brain infarct or transient ischemic attack (TIA) and PFO, 32 consecutive patients younger than 60 years who presented at least two of the following criteria were admitted for surgery: history of Valsalva strain before stroke (11); multiple clinical events (13); multiple infarcts on brain Magnetic Resonance Imaging (MRI) (15); atrial septal aneurysm (ASA) (16); large right-to-left shunt (> 50 microbubbles) (12). RESULTS: Operative time 135' +/- 33'. CPB time 34' +/- 14'. Aortic crossclamping time 16' +/- 6'. Post-operative bleeding 485 +/- 170 ml. No homologous blood transfusion required. No neurological, cardiac or renal complications. All patients were followed-up corresponding to a cumulative time of 601 patient-months. This revealed no recurrent vascular events nor silent new brain lesions on brain MRI. Systematic simultaneous contrast Trans Esophageal Echocardiography (TEE)-Trans Cranial Doppler showed a small residual interatrial shunt in two patients. CONCLUSION: Surgical closure of a patent foramen ovale can be accomplished with very low morbidity and reduce efficiently the risk of stroke recurrence. It seems to be the option of choice in selected patients with a higher (> 1.5%/year) risk of stroke recurrence.


Assuntos
Isquemia Encefálica/etiologia , Embolia Paradoxal/etiologia , Comunicação Interatrial/cirurgia , Adulto , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/prevenção & controle , Embolia Paradoxal/epidemiologia , Embolia Paradoxal/prevenção & controle , Feminino , Seguimentos , Comunicação Interatrial/complicações , Humanos , Ataque Isquêmico Transitório/epidemiologia , Ataque Isquêmico Transitório/etiologia , Ataque Isquêmico Transitório/prevenção & controle , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Sistema de Registros , Fatores de Risco
20.
Pacing Clin Electrophysiol ; 20(4 Pt 1): 909-15, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9127395

RESUMO

We hypothesized that pacing, which provided a rapid uniform contraction of the ventricles with a narrower QRS, would produce a better stroke volume and cardiac output (CO). We sought to study whether pacing simultaneously at two sites in the right ventricle (right ventricular apex and outflow tract) would provide a narrower QRS and improved CO in 11 patients undergoing elective electrophysiology studies. Patients were studied by transthoracic echocardiography measurement of CO using the Doppler flow velocity method in normal sinus rhythm, AOO pacing (rate 80), DOO pacing in the right ventricular apex (AV delay 100 ms), DOO pacing in the right ventricular outflow tract, and DOO pacing at both right ventricular sites simultaneously in random order. The COs were 5.42 +/- 1.83, 5.61 +/- 1.97, 5.67 +/- 1.6, 5.84 +/- 1.68, and 5.86 +/- 1.52 L/min, respectively (no significant difference by repeated measures analysis of variance [ANOVA]). The QRS durations were 0.09 +/- 0.02, 0.09 +/- 0.02, 0.13 +/- 0.027, 0.13 +/- 0.03, and 0.11 +/- 0.03 secs respectively. Repeated measures ANOVA showed that the QRS duration significantly increased with right ventricular apex or right ventricular outflow tract pacing compared to sinus rhythm and AOO pacing (P < 0.001) but then diminished with pacing at both sites (P < 0.01). QRS duration was not correlated with CO, however the change in QRS duration correlated significantly with the change in CO when pacing was performed at the two right ventricular sites simultaneously. In conclusion, during DOO pacing, there was a trend for pacing in the right ventricular outflow tract or both sites to improve the CO compared to the right ventricular apex. With simultaneous pacing at both ventricular sites, the QRS narrowed. Further studies will be required to see if this approach has value in patients with poor left ventricular function or congestive heart failure.


Assuntos
Estimulação Cardíaca Artificial/métodos , Hemodinâmica , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Débito Cardíaco , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico
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