RESUMEN
AIMS: The relation between atrial tachyarrhythmia (ATA) burden in paroxysmal atrial fibrillation (AF), atrial remodelling, and efficacy of catheter ablation (CA) is unknown. We investigated whether high vs. low-burden paroxysmal AF patients have distinct clinical characteristics or electro-mechanical properties of the left atrium (LA) and whether burden impacts outcome of CA. METHODS AND RESULTS: Atrial tachyarrhythmia burden, defined as the percentage of time spent in ATA, was assessed by insertable cardiac monitors in 105 patients before and after CA. Clinical characteristics and electro-mechanical properties of LA were compared between patients with high vs. low ATA burden. Catheter ablation efficacy was assessed by reduction in ATA burden and 1-year freedom from any ATA. Median ATA burden was 2.7% (highest tertile 9.3%). Clinical characteristics and electrical properties of LA (refractoriness, conduction velocity, low voltage) did not differ between high (≥9.3%) vs. low ATA burden (<9.3%) patients. High ATA burden patients had larger LA diameter (46.5 ± 6 vs. 42.5 ± 6mm, P < 0.01), volume (93.8 ± 22 vs. 80.4 ± 21mL, P = 0.01), and lower LA reservoir and contractile strain (19.7 ± 6 vs. 24.7 ± 6%, P < 0.01; 10.3 ± 3 vs. 12.8 ± 4%, P = 0.01). Catheter ablation reduced ATA burden by 100% (100-100) in both groups (P = 1.0). Freedom from ATA after CA was equally high (83% vs. 89%, P = 0.38). CONCLUSION: Paroxysmal AF patients with high ATA burden have altered LA mechanical properties, reflected by larger size and impaired function. Despite mechanical remodelling of the atria, they are excellent responders to CA. Most likely the lack of fibrosis and/or advanced electrical remodelling explain why pulmonary veins remain the dominant trigger for AF in this patient cohort.
Asunto(s)
Fibrilación Atrial , Remodelación Atrial , Ablación por Catéter , Venas Pulmonares , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Fibrilación Atrial/cirugía , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/cirugía , Humanos , Venas Pulmonares/cirugía , Resultado del TratamientoRESUMEN
PURPOSE: Catheter ablation is an effective treatment for premature ventricular complexes (PVCs). Activation mapping is accurate but requires PVCs at the time of the ablation. Pace-mapping correlation (PMC) is a supplemental tool recently developed as an integrated module for an electro-anatomical mapping platform. Our study sought to investigate whether pace-mapping technology provides similar ablation results in patients with low versus high idiopathic PVC burden at the time of ablation and the relationship between sites with the highest PMC and the earliest local activation time (LAT). METHODS: A total of 59 consecutive patients undergoing catheter ablation for idiopathic PVCs were enrolled. Twelve out of 59 patients (20%) were classified in the low PVC burden group (defined as < 2 PVCs/min) and 47/59 (80%) in the high PVC burden group. RESULTS: The most common origin of PVCs was the right ventricular outflow tract (RVOT) followed by aortic cusps, coronary sinus, parahisian region, and aorto-mitral continuity. Procedural and 1-month success rate were 95 and 87% respectively. PVC burden at the time of ablation did not influence the success rate. The median distance between the earliest LAT points and the highest PMC points was 6.4 (4.9-10.6) mm. CONCLUSIONS: Pace-mapping correlation is useful and accurate in localizing the origin of idiopathic PVCs irrespective of the initial PVC burden. It provides optimal ablation results when combined with LAT. Success rate at mid-term follow-up is higher when the origin of PVCs is located in the RVOT as compared to other locations.
Asunto(s)
Mapeo del Potencial de Superficie Corporal/métodos , Ablación por Catéter/métodos , Complejos Prematuros Ventriculares/diagnóstico por imagen , Complejos Prematuros Ventriculares/cirugía , Factores de Edad , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Factores Sexuales , Resultado del TratamientoRESUMEN
Acute arrhythmia is a condition covering a wide variety of rhythm disturbances. The aim of the article is to give practical recommendations for the approach and the treatment of the patient presenting with an acute arrhythmia. We discuss bradycardia and tachycardia. Tachycardias are divided into the small QRS complex tachycardias and the wide QRS complex tachycardias. Another important distinction with immediate therapeutic consequences is that between the hemodynamic stable and unstable patient. Flowcharts with diagnostic means and therapeutic schemes are added and a table with practical considerations for electrical cardioversion.
Asunto(s)
Arritmias Cardíacas/terapia , Enfermedad Aguda , Arritmias Cardíacas/fisiopatología , Bradicardia/fisiopatología , Bradicardia/terapia , Árboles de Decisión , Humanos , Taquicardia/fisiopatología , Taquicardia/terapiaRESUMEN
The Belgium Interdisciplinary Working group on Acute Cardiology, including cardiologists, intensivists and urgentists was formed to provide consensus regarding the management of acute chest pain in the prehospital and the early hospital phase. General recommendations and critical pathways are proposed to improve the treatment of the patients with acute coronary syndromes.
Asunto(s)
Algoritmos , Angina Inestable/diagnóstico , Dolor en el Pecho/etiología , Infarto del Miocardio/diagnóstico , Guías de Práctica Clínica como Asunto , Enfermedad Aguda , Angina Inestable/complicaciones , Angina Inestable/terapia , Diagnóstico Diferencial , Humanos , Infarto del Miocardio/complicaciones , Infarto del Miocardio/terapiaRESUMEN
The Belgium Interdisciplinary Working Group on Acute Cardiology (BIWAC), including cardiologists, intensivists and urgentists was formed to give consensus regarding the management of acute chest pain in the prehospital and the early hospital phases. General recommendations and critical pathways are proposed to improve the treatment of the patients with acute coronary syndromes.
Asunto(s)
Dolor en el Pecho/terapia , Enfermedad Aguda , Dolor en el Pecho/etiología , HumanosRESUMEN
Pacemaker lead infection is a rare condition, most often occurring when intervention is needed after pacemaker implantation. Diagnosis is by blood cultures and confirmation by transoesophageal echocardiography; transthoracic echocardiography is often inadequate. A literature review indicated the microorganism most responsible for late lead infection is Staphylococcus epidermidis (which can grow on plastic material). A retrospective analysis of patient files from the authors' institution (1993-97) yielded three patients with proven pacemaker lead endocarditis. The diagnosis of pacemaker endocarditis was by transoesophageal echocardiography. The endocarditis appeared after a long period and in two of the three patients there was S epidermidis infection. Thoracotomy with removal of the infected system was performed because of the large dimensions of the vegetations. A new pacemaker was implanted: in one patient with endocardial leads, in the other two with epicardial leads. All three patients recovered well and follow up was uneventful for at least one year.
Asunto(s)
Ecocardiografía Transesofágica , Endocarditis Bacteriana/diagnóstico por imagen , Marcapaso Artificial , Infecciones Estafilocócicas/diagnóstico por imagen , Staphylococcus epidermidis , Adulto , Anciano , Endocarditis Bacteriana/cirugía , Femenino , Humanos , Masculino , Estudios Retrospectivos , Infecciones Estafilocócicas/cirugía , ToracotomíaRESUMEN
AIMS: A randomized, double-blind study with a high dose of digoxin administered intravenously for conversion of atrial fibrillation (not due to haemodynamic alternations) to sinus rhythm, and for rate control in converters and non-converters was set up. Outcome measures were conversion within 12 h; time to conversion; early rate control; and stable slowing within 12 h. METHODS: We studied 40 patients with recent onset (< 1 week) atrial fibrillation; controls received saline intravenously, the other patients digoxin 1.25 mg. RESULTS: One patient converted before digoxin administration. Conversion occurred in 9/19 patients on digoxin and in 8/20 on placebo (ns). The mean time to conversion tended to be shorter only for digoxin. Two late conversions on placebo were observed within 24 h. Heart rate during atrial fibrillation decreased after 30 min for converters and non-converters (P < 0.05). For all patients on digoxin, heart rate after 30 min was lower compared to baseline (P < 0.002) and to placebo (P < 0.02). Persistent, stable slowing occurred only in 3/10 non-converters on digoxin (P < 0.05), and two patients developed bradyarrhythmias. QTc was shortened immediately after conversion in all patients. Converters had baseline characteristics similar to those of non-converters. CONCLUSIONS: Intravenous digoxin offers no substantial advantages over placebo in recent onset atrial fibrillation with respect to conversion, and provides weak rate control.
Asunto(s)
Antiarrítmicos/administración & dosificación , Fibrilación Atrial/tratamiento farmacológico , Digoxina/administración & dosificación , Electrocardiografía/efectos de los fármacos , Anciano , Anciano de 80 o más Años , Antiarrítmicos/efectos adversos , Fibrilación Atrial/etiología , Digoxina/efectos adversos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Estudios de Seguimiento , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana EdadRESUMEN
In the current climate of rising healthcare cost, resuscitation efforts performed outside the hospital are critically evaluated because of their limited success rate in some settings. As part of a quality assurance program between the 1st January 1991 and 31st December 1993, six centres of the Belgian CPCR study group prospectively registered cardiac arrest (CA) patients and their treatment according to the Ustein Style recommendations. In the group (n = 511) of patients initially found in ventricular fibrillation (VF) a significantly better survival rate was observed for those patients who received a 1st defibrillatory shock by the 1st tier (n = 142 (27.8%)) as compared to those defibrillated after arrival of the 2nd tier (n = 369 (72.2%)). Median time to delivery of the first shock was significantly shorter (5 min) in the 1st tier group. In a second part of the study we describe long-term management of the 28 surviving VF patients, treated by the single EMS system of Brugge between 1st January 1991 and 30th April 1995: only 6 patients eventually received an implantable cardioverter defibrillator (ICD), whereas coronary revascularization was performed in 9 patients, and 3 patients were discharged on amiodarone only. Satisfactory long-term survival after out-of-hospital VF can be achieved by an early shock followed by advanced life support and appropriate definitive treatment.
Asunto(s)
Paro Cardíaco/terapia , Resucitación , Fibrilación Ventricular/terapia , Amiodarona/uso terapéutico , Antiarrítmicos/uso terapéutico , Bélgica , Puente de Arteria Coronaria , Desfibriladores Implantables , Cardioversión Eléctrica/métodos , Servicios Médicos de Urgencia , Femenino , Estudios de Seguimiento , Paro Cardíaco/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Alta del Paciente , Estudios Prospectivos , Garantía de la Calidad de Atención de Salud , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Fibrilación Ventricular/prevención & controlAsunto(s)
Puente Cardiopulmonar , Reanimación Cardiopulmonar , Paro Cardíaco/terapia , Adulto , Angioplastia Coronaria con Balón , Estimulación Cardíaca Artificial , Cardioversión Eléctrica , Urgencias Médicas , Bloqueo Cardíaco/terapia , Humanos , Masculino , Persona de Mediana Edad , Fibrilación Ventricular/terapiaAsunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco/terapia , Anciano , Anciano de 80 o más Años , Femenino , Hemodinámica , HumanosRESUMEN
To determine possible associations between lipoprotein(a) [Lp(a)] and the severity of coronary artery lesions, we measured lipid, apolipoprotein, and Lp(a) in a large population of Belgian patients (n = 1054) undergoing coronary angiography. In both women and men, univariate analysis demonstrated significant differences in the Lp(a) concentrations according to the severity of the coronary stenosis. However, after adjustment for possible confounding factors, many of these differences were attenuated, indicating that other variables that differentiate patients from control subjects also influence Lp(a) distribution. Differences in lipid, apolipoprotein, and Lp(a) concentrations between male and female patients are discussed.
Asunto(s)
Angiografía Coronaria , Enfermedad Coronaria/sangre , Lipoproteína(a)/sangre , Adulto , Anciano , Apolipoproteína A-I/metabolismo , Apolipoproteínas B/sangre , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Enfermedad Coronaria/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Caracteres Sexuales , Triglicéridos/sangreRESUMEN
CD4+ TCR-gamma delta+ T cells comprise a very small subset of TCR-gamma delta+ T cells. CD4+ TCR gamma delta+ T cell clones were established to study the phenotypical and functional characteristics of these cells. Thirty-four CD4+ TCR-gamma delta+ T cell clones were established after sorting CD4+ T cells from a pre-expanded TCR-gamma delta+ T cell population. These clones as well as the CD4- TCR-gamma delta+ T cells from the same donor used V gamma 2 and V delta 2. In a second cloning experiment CD4+ TCR-gamma delta+ T cells were cloned directly from freshly isolated TCR-gamma delta+ T cells using a cloning device coupled to a FACS sorter. Forty-three clones were obtained, which all expressed CD4 and TCR-gamma delta. Eleven of these clones used V delta 1 and three of them coexpressed V gamma 2. The other CD4+ TCR-gamma delta+ T cell clones used both V delta 2 and V gamma 2. CD4+ TCR-gamma delta+ T cell clones expressed CD28 irrespective of the V gamma or V delta usage, and were CD11b negative. Three CD4-CD8+ TCR-gamma delta+ clones expressed CD8 alpha but not CD8 beta and were CD11b positive. CD28 expression among CD4-CD8+ and CD4-CD8- was variable but lower than on CD4+ T cell clones. CD4- TCR-gamma delta+ T cell clones using V gamma 2 and V delta 2 specifically lyse the Burkitt lymphoma cell line Daudi and secrete low levels of IFN-gamma and granulocyte-macrophage-CSF upon stimulation with Daudi. In contrast, most CD4+ T cell clones that use V gamma 2 and V delta 2 had a very low lytic activity against Daudi cells and secrete high levels of IFN-gamma and granulocyte-macrophage-CSF after stimulation with Daudi cells. The NK-sensitive cell line K562 was killed efficiently by the CD4- TCR-gamma delta+ T cell clones, but not by CD4+ TCR-gamma delta+ T cell clones, and could not induce cytokine secretion in CD4+ or CD4- T cell clones. CD4+ TCR-gamma delta+ T cell clones, but not the CD4- clones, could provide bystander cognate T cell help for production of IgG, IgM, and IgA in the presence of IL-2 and IgE in the presence of IL-4. Thus, CD4+ TCR-gamma delta+ T cells are similar to CD4+ TCR-alpha beta+ T cells in their abilities to secrete high levels of cytokines and to provide T cell help in antibody production.(ABSTRACT TRUNCATED AT 400 WORDS)
Asunto(s)
Antígenos CD4/análisis , Receptores de Antígenos de Linfocitos T/análisis , Linfocitos T/inmunología , Anticuerpos Monoclonales/inmunología , Antígenos CD/análisis , Antígenos de Diferenciación de Linfocitos T/análisis , Linfocitos B/metabolismo , Antígenos CD4/fisiología , Antígenos CD8 , Células Clonales , Humanos , Inmunoglobulinas/biosíntesis , Fenotipo , Receptores de Antígenos de Linfocitos T gamma-deltaRESUMEN
Early recurrence of symptoms after successful coronary angioplasty is usually due to restenosis of the angioplasty site. Multilesion progression of atherosclerosis in the presence of patent prior dilated segments has not, to our knowledge, been reported as a cause of early recurrent angina after successful double coronary angioplasty. As both new lesions were also successfully dilated, this case demonstrates that multivessel coronary angioplasty is a repeatedly effective and patient-friendly procedure to treat symptomatic coronary atherosclerosis with rapid and unpredictable rate of progression.
Asunto(s)
Angina de Pecho/terapia , Angioplastia de Balón/efectos adversos , Arteriosclerosis/terapia , Angiografía Coronaria , Humanos , Masculino , Persona de Mediana Edad , RecurrenciaRESUMEN
Two cases of coronary occlusion and subsequent embolization during percutaneous coronary angioplasty (PTCA) are described. Prior to PTCA, angiographic evidence of intracoronary thrombus was present. Abrupt reclosure after dilation was treated by successful redilation. However, coronary embolization of thrombus debris occurred downstream in one patient and into an adjacent coronary branch in the second patient.
Asunto(s)
Angioplastia de Balón/efectos adversos , Enfermedad Coronaria/complicaciones , Trombosis Coronaria/complicaciones , Embolia/etiología , Enfermedad Coronaria/terapia , Humanos , Masculino , Persona de Mediana EdadRESUMEN
During dual chamber pacing it is sometimes impossible to assess atrial capture even on the 12-lead ECG. We developed a strategy to identify atrial capture when it is not possible to do so by ECG, and when the ECG shows no evidence of spontaneous or paced atrial activity.