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Seah Nisam

Publications and source records attributed to Seah Nisam.

7 recordsLinked to original sources
PubMed2006

The cost of implantable defibrillators: perceptions and reality.

AIMS: Recent guidelines have recommended more wide-ranging indications for the use of implantable cardioverter defibrillator (ICD) therapy, yet even more restrained previous guidelines have not been implemented for a variety of reasons. METHODS AND RESULTS: This brief review critically examines the reasons most frequently put forward to explain this failure. Contrary to the frequently repeated speculation that the risk stratification for sudden death and hence prophylactic placement of ICDs is reasonably accurate, there is little cost difference between pharmacotherapy and ICD treatment over the long term. ICD therapy does not utilize an undue proportion of the healthcare budget, and the healthcare systems in Europe can afford this therapy. CONCLUSION: Financial reasons are neither accurate nor adequate explanations for the failure of the European medical community to implement European guidelines for the implantation of ICDs for primary and secondary prevention of sudden cardiac death.

Cardiovascular Agents↗
PubMed2006

ICD therapy: 'the sickest benefit the most...': what about the less sick?

Implantable cardioverter defibrillators (ICDs) have been proven to be highly efficacious in protecting very high-risk cardiac patients from sudden cardiac death and hence enhancing their overall survival. Furthermore, several post hoc sub-study analyses seem to indicate that ICD benefit is predominant in the patients with the highest risk, particularly with depressed left ventricular function. This, in turn, has led some clinicians to question the benefit of ICD therapy in relatively healthy, i.e. 'less sick', patients. As these interpretations come entirely from the sub-group analyses of the completed ICD prospective studies, it is important to examine more profoundly the study design, length of follow-up, and outcomes of these studies. Such analysis identifies three primary reasons why the conclusion that 'less sick' patients benefit less from ICD therapy may be erroneous: (i) the relatively short follow-up time of the studies (ended as soon as ICD therapy benefit became manifest); (ii) high 'crossover rate' from control to ICD therapy; and (iii) predominance of study endpoints (deaths) in the 'sickest' patients. The results of several studies, including the most recent and largest ICD study-SCD-Heft-and sub-group analyses of 'healthier' patient cohorts in several studies, support the benefit of ICDs in this group of patients, provided the follow-up time is sufficiently long.

Clinical Trials as Topic↗
PubMed2006

Lessons learned from neutral ICD trials.

Multiple prospective randomized trials with implantable cardioverter defibrillators (ICDs) over the past decade have convincingly established the efficacy of ICD therapy in reducing all-cause mortality, by significantly reducing sudden cardiac death. Nevertheless, four trials have failed to show improved survival. Analysing these, in comparison with the positive trials, provides important information concerning the type of patients not likely to receive benefit from ICDs: (i) those with relatively low mortality (< or = 18% within 2 years of follow-up; (ii) those whose mechanism of death is predominantly non-arrhythmic; (iii) patients early (within 6 weeks) after infarction.

Arrhythmias, Cardiac↗
PubMed2005

Early EPS/ICD strategy in survivors of acute myocardial infarction with severe left ventricular dysfunction on optimal beta-blocker treatment. The BEta-blocker STrategy plus ICD trial.

AIMS: This multicentre prospective randomised trial was undertaken to evaluate the usefulness of an electrophysiological study (EPS)-guided/implantable cardioverter defibrillator (ICD) strategy in patients at high risk of sudden death (SD) early after myocardial infarction (MI). Previous studies have shown the benefits of such a strategy only in high-risk patients late after MI. METHODS AND RESULTS: We enrolled 143 survivors of acute MI (<1 month) with left ventricular ejection fraction < or = 35% and either frequent (> or =10/h) premature ventricular complexes (PVCs), or depressed heart rate variability (SDNN < 70 ms) or abnormal signal-averaged ECG, who were able to tolerate optimised beta-blocker therapy (68 +/- 40 mg/day of metoprolol). Of these, 138 were randomised, in a 2:3 ratio, to two therapeutic strategies: conventional (CONV) strategy (n = 59) or EPS-guided/ICD strategy (n = 79). The latter resulted in ICD implantation in 24 inducible patients and in CONV therapy in the remaining 55. During a mean follow-up of 540 +/- 378 days, 26 patients (19%) died: nine (6.5%) SD, nine (6.5%) non-SD, and four (3%) non-cardiac death; in four patients (3%) the cause of death was unknown. The actuarial overall mortality for the CONV and EPS-guided/ICD arms was 18% vs 14% after 1 year and 29.5% vs 20% after 2 years, respectively (P = 0.3 and 0.2). CONCLUSIONS: Despite optimal therapy, mortality remains significant in high-risk patients following MI. Although there is a trend in favour of EPS-guided/ICD, our data are insufficient to demonstrate a survival benefit of this strategy early after MI.

Adrenergic beta-Antagonists↗
PubMed2002

Do ACE inhibitors or angiotensin II antagonists reduce total mortality and arrhythmic mortality? A critical review of controlled clinical trials.

ACE-inhibitors (ACE-I) represent effective drugs more and more widely used in acute myocardial infarction (AMI) patients, in post AMI patients and mainly, today, in CHF patients.A complete review of the scientific literature and of all the randomized controlled clinical trials (RCTs), where ACE-I have been tested directly or in association with other drugs, have been performed. ACE-I effects on total mortality (TM) and arrhythmic mortality (AM) and other composite clinical endpoints have been evaluated. It is well known that frequent ventricular arrhythmias (VA) and a high incidence of sudden death (SD) can be documented in CHF patients; nevertheless a direct relationship between VA, TM, and AM has not been clearly demonstrated; neither beneficial effects, on the same endpoints, of the treatment and suppression of ambient VA in CHF. Conversely, sometimes clear negative effects on both TM and AM have been observed. According to individual studies and two recent complete and large metanalysis, ACE-I were unable to reduce AM, but they reduced TM. Furthermore, they can affect and modify many, if not all, of the triggering factors of VA and SD in this context. Differently from ACE-I, betablockers (BB) have been clearly associated with a reduction in TM and AM, in the same context. Thus, at present time, ACE-I, with or without BB, should be considered the standard therapy in all patients with CHF, if not contraindicated. Angiotensin II antagonists (AII-a) probably represent a comparably effective treatment, in all CHF patients and mainly in those patients, suffering from side effects or showing intolerance to ACE-I, but we are still lacking definitive data from RCTs. In many RCTs, conducted with traditional antiarrhythmic drug therapy (ADT), these drugs have been widely used, contributing probably, in a consistent way, to some of the positive results of these studies. All primary and some secondary implantable defibrillators (ICD) RCTs, in the prevention of SD, have included these drugs as the standard treatment of the underlying cardiac disease, with or without CHF. The same therapeutical strategy is regularly applied in all biventricular pacing (BP) RCTs, with or without the ICD. These trials are supposed to assess the reduction in TM and AM, preventing deterioration or progression of CHF and improving the quality of the patients' s life.Finally, according to these clinical evidences, in the last part of the review, we stress the need for a more widespread implementation of ACE-I and AII-a in treating CHF patients.

Adrenergic beta-Antagonists↗
PubMed2002

Implementation of MADIT and MUSTT in clinical practice: results of an international survey.

BACKGROUND: The long-awaited dramatically positive outcome of the Multicenter Automatic Defibrillator Implantation Trial (MADIT II), just published by Moss et al.,(14) has generated cardiologists' interest on the implementation into clinical practice of that trial. Important lessons may be learned by examining the clinical implementation of two preceding randomized, prospective, prophylactic ICD trials: the original MADIT trial, published late 1996, and the Multicenter Unsustained Tachycardia Trial (MUSTT), published late 1999. Both demonstrated that implantable cardioverter defibrillators reduce all-cause mortality by over 50% in high risk patients without previous sustained arrhythmias. METHODS: In early 2000, we surveyed 133 active electrophysiology centers (47 American, 81 European, 5 Canadian) to determine the extent to which these practices have been implemented in clinical practice during 1999, and the responses were compared to a similar survey for the year 1998. RESULTS: ICDs implanted for MADIT or MUSTT criteria accounted for 18% of new ICD implants in 1999, 65% greater than in 1998, increasing from 6% to 11% in Europe, and from 15% to 24% in America. During 1999, 53% of patients receiving ICDs for these indications were inpatients identified during hospitalization, 27% were outpatients referred specifically for MADIT/MUSTT indications, and 20% were identified by routine screening. Per the survey, in 1999 68% of responders were "somewhat (10-20%)" and 14% were "considerably (>20%)" more likely to implant ICDs for all indications. CONCLUSIONS: Extrapolating the results of this survey to all initial ICD implants for 1999, we estimate that 8500 implants for MADIT/MUSTT criteria took place in 1999, with the overall number of such implants substantially increased over the previous year, irrespective of geographic location, and influenced significantly by the publication of MUSTT. However, screening and implant practices between centers continue to vary over a broad spectrum. It will be interesting to observe whether similar patterns will follow with MADIT II.

Clinical Trials as Topic↗