Left Bundle Branch Block, an Old–New Entity

Left bundle branch block (LBBB) is generally associated with a poorer prognosis in comparison to normal intraventricular conduction, but also in comparison to right bundle branch block which is generally considered to be benign in the absence of an underlying cardiac disorder like congenital heart disease. LBBB may be the first manifestation of a more diffuse myocardial disease. The typical surface ECG feature of LBBB is a prolongation of QRS above 0.11 s in combination with a delay of the intrinsic deflection in leads V5 and V6 of more than 60 ms and no septal q waves in leads I, V5, and V6 due to the abnormal septal activation from right to left. LBBB may induce abnormalities in left ventricular performance due to abnormal asynchronous contraction patterns which can be compensated by biventricular pacing (resynchronization therapy). Asynchronous electrical activation of the ventricles causes regional differences in workload which may lead to asymmetric hypertrophy and left ventricular dilatation, especially due to increased wall mass in late-activated regions, which may aggravate preexisting left ventricular pumping performance or even induce it. Of special interest are patients with LBBB and normal left ventricular dimensions and normal ejection fraction at rest but who may present with an abnormal increase in pulmonary artery pressure during exercise, production of lactate during high-rate pacing, signs of ischemia on myocardial scintigrams (but no coronary artery narrowing), and abnormal ultrastructural findings on myocardial biopsy. For this entity, the term latent cardiomyopathy had been suggested previously

Het Rijnlands model als inspiratiebron

West-Europa heeft op politiek/maatschappelijk vlak en op het gebied van ondernemerschap een lange en succesvolle traditie. Deze traditie wordt onder andere gekenmerkt door: meenemen van de belangen van alle ‘stakeholders’ van een organisatie; denken in termen van ‘gemeenschap’; rekening houden met maatschappelijke factoren als natuur, milieu en werkgelegenheid; innovatie, design en vernieuwingen op het gebied van kunst en wetenschap, alles bij elkaar ook wel het ‘Rijnlands model’ genoemd. Hiertegenover staat het Anglo- Amerikaanse model, een traditie die bepaald wordt door het Britse en vooral het Noord-Amerikaanse denken. Kenmerken zijn onder andere: dominantie van het bedrijfsleven binnen de samenleving; marktdenken; ‘shareholder value’ als belangrijkste criterium; processen en samenwerken binnen organisaties worden als rationeel gezien; efficiëntiedenken; gerichtheid op kortetermijnresultaten; individualisering en materialisme. Het denken vanuit het Anglo-Amerikaanse model wordt ook in Nederland dominanter. De auteurs zien dit bij het overheidsbeleid, bij het denken en handelen van bedrijven en hun managers en bij de invulling van managementopleidingen. Zij vinden deze groeiende invloed van het Anglo-Amerikaanse model zorgelijk. Vanuit deze zorg hebben zij in juli 2004 een conferentie georganiseerd. In dit artikel presenteren en bespreken de auteurs onder meer de resultaten van deze conferentie. Zij betogen dat de toenemende dominantie van het Anglo- Amerikaanse denken niet onomkeerbaar is

RANDOMIZED STUDY OF IMPLANTABLE DEFIBRILLATOR AS FIRST-CHOICE THERAPY VERSUS CONVENTIONAL STRATEGY IN POSTINFARCT SUDDEN-DEATH SURVIVORS

Background In retrospective studies of sudden cardiac death survivors, the implantable cardioverter-defibrillator (ICD) compares favorably with medical and surgical therapy. Thus, use of the conventional strategy of starting treatment with antiarrhythmic drugs (AD), at least in certain patient categories, may be questionable. The goal of this study was to analyze the effectiveness of ICD implantation as first-choice therapy versus the conventional therapeutic strategy of starting with AD. Methods and Results Sixty consecutive survivors of cardiac arrest caused by old myocardial infarction were randomly assigned early ICD implantation (n=29) or conventional therapy (n=31). Baseline characteristics were similar in the two groups. Therapy in each patient was always guided by ECG monitoring, exercise testing, and programmed electrical stimulation (PES). Primary end points (main outcome events, including death, recurrent cardiac arrest, and cardiac transplantation), number of invasive procedures and antiarrhythmic therapy changes, and duration of hospitalization were compared. Median follow-up was 24 months (mean, 27 months). In the early ICD group, 4 patients (14%) died, all of cardiac causes. In the conventional group, 20 patients failed AD and subsequently underwent map-guided ventricular tachycardia (VT) surgery (6 patients) or ICD implantation (14 patients). Of the 6 VT surgery patients, 1 died, 1 had cardiac transplantation, and 1 had an ICD implantation because of persistent inducibility despite the addition of AD. Of the 11 patients who remained on AD as sole therapy, 2 died in the hospital before they could be retested by PES, leaving 9, judged adequately protected by AD alone. Of those, 5 died, and 1 survived recurrent cardiac an est followed by ICD implantation. In total, 16 conventionally treated patients ended up with late ICD implantation, 3 of whom died. Thus, total mortality in the conventional group was 11 patients (35%): 4 died suddenly, 5 died of heart failure, and 2 died of noncardiac causes. Comparison of the main outcome events in both strategies showed a significant difference in favor of early ICD implantation (hazard ratio, 0.27; 95% CI, 0.09 to 0.85; P=.02). In addition, the early ICD group underwent fewer invasive procedures (median, 1 versus 3; P Conclusions These data suggest that ICD implantation as first choice is preferable to the conventional approach in survivors of cardiac arrest caused by old myocardial infarction. Conventionally treated patients are likely to end up with an ICD, and those who remain on AD as sole therapy have a high risk of death regardless of efficacy assessment, including PES

Cost-effectiveness of implantable defibrillator as first-choice therapy versus electrophysiologically guided, tiered strategy in postinfarct sudden death survivors - A randomized study

Background Rising costs of health care, partly as a result of costly therapeutic innovations, are of concern to both the medical profession and healthcare authorities. The implantable cardioverter-defibrillator or (ICD) is still not remunerated by Dutch healthcare insurers. The aim of this study was to evaluate the cost-effectiveness of early implantation of the ICD in postinfarct sudden death survivors. Methods and Results Sixty consecutive postinfarct survivors of cardiac arrest caused by ventricular tachycardia or fibrillation were randomly assigned either ICD as first choice (n=29) or a tiered therapy starting with antiarrhythmic drugs and guided by electrophysiological (EP) testing (n=31). Median follow-up was 729 days (range, 3 to 1675 days). Fifteen patients died, 4 in the early ICD group and 11 in the EP-guided strategy group (P=.07). For quantitative assessment, the cost-effectiveness ratio was calculated for both groups and expressed as median total costs per patient per day alive. Because effectiveness aspects other than mortality are not incorporated in this ratio, other factors related to quality of life were used as qualitative measures of cost-effectiveness. The cost-effectiveness ratios were $63 and$94 for the early ICD and EP-guided strategy groups, respectively, per patient per day alive. This amounts to a net cost-effectiveness of $11 315 per patient per year alive saved by early ICD implantation. Costs in the early ICD group were higher only during the first 3 months of followup, but as a result of the high proportion of therapy changes, including arrhythmia surgery and late ICD implantation, costs in the EP-guided strategy group became higher after that. Patients discharged with antiarrhythmic drugs as sole therapy had the lowest total costs. This subset, however, showed extremely high mortality, resulting in a poor cost-effectiveness ratio ($196 per day). Invasive therapies and hospitalization were the major contributors to costs. If quality-of-life measures are taken into account, the cost-effectiveness of early ICD implantation was even more favorable. Recurrent cardiac arrest and cardiac transplantation occurred in the EP-guided strategy group only, whereas exercise tolerance, total hospitalization duration, number of invasive procedures, and antiarrhythmic therapy changes were significantly in favor of early ICD implantation. Conclusions In terms of cost-effectiveness, early ICD implantation is superior to the EP-guided therapeutic strategy in postinfarct sudden death survivors