RESUMEN
BACKGROUND: It is apparent that despite lack of family history, patients with the morphological characteristics of left ventricular non-compaction develop arrhythmias, thrombo-embolism and left ventricular dysfunction. METHODS: Forty two patients, aged 48.7 +/- 2.3 yrs (mean +/- SEM) underwent cardiovascular magnetic resonance (CMR) for the quantification of left ventricular volumes and extent of non-compacted (NC) myocardium. The latter was quantified using planimetry on the two-chamber long axis LV view (NC area). The patients included those referred specifically for CMR to investigate suspected cardiomyopathy, and as such is represents a selected group of patients. RESULTS: At presentation, 50% had dyspnoea, 19% chest pain, 14% palpitations and 5% stroke. Pulmonary embolism had occurred in 7% and brachial artery embolism in 2%. The ECG was abnormal in 81% and atrial fibrillation occurred in 29%. Transthoracic echocardiograms showed features of NC in only 10%. On CMR, patients who presented with dyspnoea had greater left ventricular volumes (both p < 0.0001) and a lower left ventricular ejection fraction (LVEF) (p < 0.0001) than age-matched, healthy controls. In patients without dyspnoea (n = 21), NC area correlated positively with end-diastolic volume (r = 0.52, p = 0.0184) and end-systolic volume (r = 0.56, p = 0.0095), and negatively with EF (r = -0.72, p = 0.0001). CONCLUSION: Left ventricular non-compaction is associated with dysrrhythmias, thromboembolic events, chest pain and LV dysfunction. The inverse correlation between NC area and EF suggests that NC contributes to left ventricular dysfunction.
Asunto(s)
No Compactación Aislada del Miocardio Ventricular/diagnóstico , Imagen por Resonancia Cinemagnética , Disfunción Ventricular Izquierda/diagnóstico , Angina de Pecho/diagnóstico , Angina de Pecho/etiología , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiología , Arteriopatías Oclusivas/diagnóstico , Arteriopatías Oclusivas/etiología , Arteria Braquial/patología , Estudios de Casos y Controles , Disnea/diagnóstico , Disnea/etiología , Ecoencefalografía , Electrocardiografía , Femenino , Humanos , No Compactación Aislada del Miocardio Ventricular/complicaciones , No Compactación Aislada del Miocardio Ventricular/fisiopatología , Masculino , Persona de Mediana Edad , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/etiología , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/etiología , Volumen Sistólico , Factores de Tiempo , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
Dilated cardiomyopathy (DCM) is a common and malignant condition, which carries a poor long-term prognosis. Underlying disease aetiologies are varied, and often carry specific implications for treatment and prognosis. The role of echocardiography is essential in not only establishing the diagnosis, but also in defining the aetiology, and understanding the pathophysiology. This article therefore explores the pivotal role of echocardiography in the evaluation and management of patients with DCM.
Asunto(s)
Cardiomiopatía Dilatada/diagnóstico por imagen , Cardiomiopatía Dilatada/terapia , Ecocardiografía/métodos , Cardiomiopatía Dilatada/etiología , Cardiomiopatía Dilatada/fisiopatología , Diagnóstico Diferencial , Humanos , PronósticoRESUMEN
Beta-blockers are normally contraindicated in the treatment of cardiogenic shock. A 70-year-old lady presents with an acute coronary syndrome complicated by critical cardiogenic shock. Coronary angiography shows an ulcerated nonobstructing plaque in the left anterior descending artery. She fails to improve with standard treatment with inotrope and intraaortic balloon pump. Echocardiography revealed acquired left ventricular outflow tract (LVOT) obstruction and secondary mitral regurgitation. Treatment with intravenous beta-blockers produced both clinical and hemodynamic improvement as well as resolution of LVOT obstruction. Echocardiography is essential in defining the mechanism of cardiogenic shock in patients with acute coronary syndrome. Inotropic support exacerbates cardiogenic shock due to acquired LVOT obstruction that is best treated with beta-blockers.
Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Propanolaminas/uso terapéutico , Choque Cardiogénico/tratamiento farmacológico , Obstrucción del Flujo Ventricular Externo/tratamiento farmacológico , Anciano , Electrocardiografía , Femenino , Humanos , Choque Cardiogénico/diagnóstico , Choque Cardiogénico/etiología , Obstrucción del Flujo Ventricular Externo/diagnóstico , Obstrucción del Flujo Ventricular Externo/etiologíaRESUMEN
AIM: To determine whether myocardial scarring, quantified using late gadolinium enhancement-cardiovascular magnetic resonance (LGE-CMR), predicts response to cardiac resynchronization therapy (CRT). METHODS AND RESULTS: A total of 45 patients with ischaemic cardiomyopathy [age 67.1 +/- 10.4 years (mean +/- SD)] underwent assessment of 6 min walking distance (6MWD) and quality of life (QoL) before and after CRT. Scar size (percentage of left ventricular mass), location, and transmurality were assessed prior to CRT using LGE-CMR. Responders (survived for 1 year with no heart failure hospitalizations, and improvement by >or=1 NYHA classes or >or=25% 6MWD) had a higher left ventricular ejection fraction (P = 0.048), smaller scars (<33%) (P = 0.009), and fewer scars with >or=51% transmurality (P = 0.002). Scar size correlated negatively with change in 6MWD (r = -0.54, P < 0.001) and positively with changes in QoL scores (r = 0.35, P = 0.028). Responder rates in patients with <33% scar were higher than in those with >or=33% scar (82 vs. 35%, P < 0.01). Responder rates in patients with scar transmurality <51% were higher than in those with >or=51% (89 vs. 46%, P < 0.01). Among the patients with posterolateral scars, a transmurality value of >or=51% was associated with a particularly poor response rate (23%), compared with scars with <51% transmurality (88%, P < 0.001). In multivariate analyses, both scar size (P = 0.022) and transmurality (P = 0.004) emerged as predictors of response. In patients with posterolateral scars, pacing outside the scar was associated with a better responder rate than pacing over the scar (86 vs. 33%, P = 0.004). CONCLUSIONS: In patients with ischaemic cardiomyopathy, a scar size >or=33%, a transmurality >or=51%, and pacing over a posterolateral scar are associated with a suboptimal response to CRT.
Asunto(s)
Estimulación Cardíaca Artificial/métodos , Gadolinio , Imagen por Resonancia Magnética/métodos , Isquemia Miocárdica/patología , Isquemia Miocárdica/terapia , Anciano , Cicatriz/diagnóstico por imagen , Cicatriz/patología , Ecocardiografía , Tolerancia al Ejercicio/fisiología , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Isquemia Miocárdica/diagnóstico por imagen , Miocardio/patología , Valor Predictivo de las Pruebas , Calidad de Vida , Resultado del TratamientoRESUMEN
OBJECTIVE: We sought to conduct a randomized trial comparing late revascularization with conservative therapy in symptom-free patients after acute myocardial infarction (AMI). BACKGROUND: In the absence of ischemia, the benefits of reperfusion late after AMI remain controversial. However, the possibility exists that an open infarct related artery benefits healing post AMI. METHODS: Of 223 patients enrolled with Q-wave anterior AMI, 66 with isolated persistent occlusion of the left anterior descending coronary artery (LAD) were randomized to the following treatments: 1) medical therapy (closed artery group; n = 34) or 2) late intervention and stent to the LAD + medical therapy (open artery group; n = 32). The study was powered to compare left ventricular (LV) end-systolic volume between the two groups 12 months post AMI. RESULTS: Late intervention 26 +/- 18 days post AMI resulted in significantly greater LV end-systolic and end-diastolic volumes at 12 months than medical therapy alone (106.6 +/- 37.5 ml vs. 79.7 +/- 34.4 ml, p < 0.01 and 162.0 +/- 51.4 ml vs. 130.1 +/- 46.1 ml, p < 0.01, respectively). Exercise duration and peak workload significantly increased in both groups from 6 weeks to 12 months post AMI, although absolute values were greater in the open artery group. Quality of life scores tended to deteriorate during this time interval in the closed artery patients but remained unchanged in the open artery patients. Coronary angiography at 1 year documented a low incidence of intergroup cross-over (spontaneous recanalization in 19% and closure in 11%). CONCLUSIONS: In the present study, recanalization of occluded infarct-related arteries in symptom-free patients approximately 1 month post AMI had an adverse effect on remodeling but tended to increase exercise tolerance and improve quality of life.
Asunto(s)
Tolerancia al Ejercicio , Infarto del Miocardio/terapia , Calidad de Vida , Función Ventricular Izquierda/fisiología , Angiografía Coronaria , Femenino , Estudios de Seguimiento , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/tratamiento farmacológico , StentsRESUMEN
BACKGROUND: Heart failure patients with stable angina, acute coronary syndromes and valvular heart disease may benefit from revascularisation and/or valve surgery. However, the mortality rate is increased- 5-30%. Biventricular pacing using temporary epicardial wires after surgery is a potential mechanism to improve cardiac function and clinical endpoints. METHOD/DESIGN: A multi-centred, prospective, randomised, single-blinded, intervention-control trial of temporary biventricular pacing versus standard pacing. Patients with ischaemic cardiomyopathy, valvular heart disease or both, an ejection fraction ≤ 35% and a conventional indication for cardiac surgery will be recruited from 2 cardiac centres. Baseline investigations will include: an electrocardiogram to confirm sinus rhythm and measure QRS duration; echocardiogram to evaluate left ventricular function and markers of mechanical dyssynchrony; dobutamine echocardiogram for viability and blood tests for renal function and biomarkers of myocardial injury- troponin T and brain naturetic peptide. Blood tests will be repeated at 18, 48 and 72 hours. The principal exclusions will be subjects with permanent atrial arrhythmias, permanent pacemakers, infective endocarditis or end-stage renal disease.After surgery, temporary pacing wires will be attached to the postero-lateral wall of the left ventricle, the right atrium and right ventricle and connected to a triple chamber temporary pacemaker. Subjects will be randomised to receive either temporary biventricular pacing or standard pacing (atrial inhibited pacing or atrial-synchronous right ventricular pacing) for 48 hours.The primary endpoint will be the duration of level 3 care. In brief, this is the requirement for invasive ventilation, multi-organ support or more than one inotrope/vasoconstrictor. Haemodynamic studies will be performed at baseline, 6, 18 and 24 hours after surgery using a pulmonary arterial catheter. Measurements will be taken in the following pacing modes: atrial inhibited; right ventricular only; atrial synchronous-right ventricular; atrial synchronous-left ventricular and biventricular pacing. Optimisation of the atrioventricular and interventricular delay will be performed in the biventricular pacing group at 18 hours. The effect of biventricular pacing on myocardial injury, post operative arrhythmias and renal function will also be quantified. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01027299.
Asunto(s)
Estimulación Cardíaca Artificial/métodos , Terapia de Resincronización Cardíaca/métodos , Procedimientos Quirúrgicos Cardíacos , Cardiopatías/cirugía , Insuficiencia Cardíaca/terapia , Pericardio/fisiopatología , Proyectos de Investigación , Función Ventricular Derecha , Biomarcadores/sangre , Cardiopatías/complicaciones , Cardiopatías/diagnóstico , Cardiopatías/fisiopatología , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Hemodinámica , Humanos , Estudios Prospectivos , Método Simple Ciego , Factores de Tiempo , Resultado del Tratamiento , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/terapia , Función Ventricular Izquierda , GalesRESUMEN
OBJECTIVES: Optimized temporary bi-ventricular (BiV) pacing may benefit heart failure patients after on-pump cardiac surgery compared with conventional dual-chamber right ventricular (RV) pacing. An improvement in haemodynamic function with BiV pacing may reduce the duration of 'Level 3' intensive care. METHODS: Thirty-eight patients in sinus rhythm, ejection fraction ≤35%, undergoing on-pump surgical revascularization, valve surgery or both were enrolled in this study. Before closing the sternum, temporary epicardial pacing wires were attached to the right atrium, RV outflow tract and basal posterolateral wall of the left ventricle. Patients were randomly assigned to postoperative BiV pacing with the optimization of the atrio- (AV) and inter-ventricular (VV) pacing intervals (Group 1) or conventional dual-chamber right AV pacing (Group 2). The primary end-point was the duration of 'Level 3' intensive care. Secondary end-points included cardiac output which was measured by thermodiluation at admission to the intensive care unit and at 6 and 18 h later, in five different pacing modes. RESULTS: The duration of 'Level 3' care was similar between groups (40 ± 35 vs 54 ± 63 h; Group 1 vs 2; P = 0.43). Cardiac output was similar in all pacing modes at baseline. At 18 h, cardiac output with BiV pacing (5.8 l/min) was 7% higher than atrial inhibited (5.4 l/min) and 9% higher than dual-chamber RV pacing (5.3 l/min; P = 0.02 and 0.001, respectively). Optimization of the VV interval produced a further 4% increase in cardiac output compared with baseline settings (P = 0.005). CONCLUSIONS: Postoperative haemodynamic function may be enhanced by temporary BiV pacing of high-risk patients after on-pump cardiac surgery.
Asunto(s)
Terapia de Resincronización Cardíaca/métodos , Puente Cardiopulmonar , Puente de Arteria Coronaria , Insuficiencia Cardíaca/cirugía , Implantación de Prótesis de Válvulas Cardíacas , Cuidados Posoperatorios/métodos , Disfunción Ventricular Izquierda/complicaciones , Anciano , Biomarcadores/sangre , Gasto Cardíaco , Cuidados Críticos/estadística & datos numéricos , Femenino , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Método Simple Ciego , Resultado del Tratamiento , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
AIMS: Dyssynchrony assessment in cardiac resynchronization therapy (CRT) is controversial, and there are no standard protocols for optimizing treatment. We studied the feasibility and reproducibility of several echocardiographic measures to optimize CRT pacemaker settings. We also assessed the utility of 'stroke distance' [left ventricular outflow tract velocity-time integral (LVOT VTI)] in performing this function. METHODS AND RESULTS: Thirty patients underwent the following functional assessments; 6 min walk test distance, peak VO(2) consumption on cardiopulmonary exercise testing (VO(2) peak), quality-of-life scoring, and echocardiography; before and at 3 and 6 months after implantation of the CRT device. At 3 months, patients received LVOT VTI-guided optimization of interventricular (VV) and atrioventricular (AV) delays. The feasibility and reproducibility of each optimization measurement was statistically analysed, and the functional benefits of optimization examined. Left ventricular outflow tract VTI, interventricular mechanical delay (IVMD), and tissue Doppler lateral-septal delay showed good feasibility (>90%), whereas LVOT VTI, IVMD, and the 12-segment tissue Doppler dyssynchrony index showed good reproducibility (coefficient of variation <20%). The most feasible and reproducible measure was LVOT VTI. Our optimization protocol necessitated alteration of AV and/or VV delays in 60% of patients at 3 months and was associated with a 50% improvement in functional responder status between 3 and 6 months. CONCLUSION: Left ventricular outflow tract VTI provides us with a single, direct measure of global LV function which is robust, and easily applicable in routine clinical practice, and which is effective at improving response to CRT.
Asunto(s)
Estimulación Cardíaca Artificial/métodos , Insuficiencia Cardíaca/terapia , Consumo de Oxígeno , Volumen Sistólico , Ultrasonografía Doppler , Análisis de Varianza , Gasto Cardíaco , Prueba de Esfuerzo , Estudios de Factibilidad , Femenino , Indicadores de Salud , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/diagnóstico por imagen , Isquemia Miocárdica/terapia , Estudios Prospectivos , Calidad de Vida , Reproducibilidad de los Resultados , Estadística como Asunto , Encuestas y CuestionariosAsunto(s)
Estenosis Coronaria/diagnóstico , Reserva del Flujo Fraccional Miocárdico , Insuficiencia Cardíaca/diagnóstico , Sístole , Función Ventricular Izquierda , Angioplastia Coronaria con Balón/instrumentación , Angiografía Coronaria , Estenosis Coronaria/complicaciones , Estenosis Coronaria/fisiopatología , Estenosis Coronaria/terapia , Femenino , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Edema Pulmonar/etiología , Edema Pulmonar/fisiopatología , Índice de Severidad de la Enfermedad , Stents , Resultado del TratamientoRESUMEN
OBJECTIVES: This study was designed to determine whether cardiac resynchronization therapy (CRT) by means of biventricular pacing (BiVP) alters the QT interval (QT(c)) and QT dispersion (QTD), and whether such changes relate to the risk of developing major arrhythmic events (MAE). BACKGROUND: Prolonged QT(c) is associated with MAE. Left ventricular pacing and BiVP alter QT(c). METHODS: A total of 75 patients with drug-resistant heart failure (New York Heart Association functional class III/IV) and QRS duration > or =120 ms underwent CRT. The QT(c) and QTD were measured before and 48 days after BiVP. RESULTS: Over 807 days (range 93 to 1,543 days), 11 patients had a MAE. Compared to baseline, at 48 days after CRT, QTD increased in 47% of patients and QT(c) decreased in 53%. The QT(c) at follow-up was higher in MAE patients compared with no-MAE patients (35.9 +/- 14.2 ms vs. 0.52 +/- 6.0 ms; p = 0.0323). Similar differential responses for QTD were observed (46.4 +/- 13.5 ms in MAE vs. -5.1 +/- 4.1 ms in no MAE, p < 0.0001). The MAE occurred in 29% of patients exhibiting an increase in QTD and in 3% of those exhibiting a decrease (p = 0.0017). In multiple regression analyses, change in QTD from baseline (DeltaQTD) strongly predicted MAE, independent of DeltaQT(c), QRS duration, and left ventricular ejection fraction and end-diastolic volume (p < 0.001). Differences in survival curves were observed when patients were dichotomized according to whether QTD increased or decreased in relation to baseline values (p < 0.0001). CONCLUSIONS: The MAE in patients with BiVP are related to pacing-induced increases in QTD. Measures of ventricular repolarization at the time of pacemaker implantation may guide selection of patients for combined CRT and defibrillator therapy.