Publications by authors named "Anne-Christine H Ruwald"

Background: Data on inappropriate implantable cardioverter-defibrillator (ICD) therapy and effects of programming by heart rate are lacking.

Objective: We aimed to characterize inappropriate ICD therapy and assess the effects of novel programming by heart rate.

Methods: Incidence and causes of inappropriate therapy by heart rate range (below or above 200 bpm) were assessed.

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Background: There are limited data whether history of atrial tachyarrhythmia (AT) modifies the risk of inappropriate ICD therapy, or the efficacy of novel ICD programming to reduce inappropriate ICD therapy events.

Methods: In MADIT-RIT, we investigated the effects of novel ICD programming with high-rate cut-off VT zone ≥ 200 bpm (arm B), or 60-second delayed therapy in the VT zone 170-199 bpm (arm C), compared to conventional programming VT zone>170 bpm (arm A) on first inappropriate ICD therapy in those with or those without AT prior to enrollment.

Results: In patients with prior AT (n = 203, 14%) there was a higher risk of inappropriate ICD therapy (HR = 2.

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Aims: Data on the time-dependent benefit of cardiac resynchronization therapy with defibrillator (CRT-D) compared with a dual-chamber implantable cardioverter-defibrillator (ICD) to reduce death or ventricular tachycardia (VT) or ventricular fibrillation (VF) are limited. We aimed to evaluate the time-related risk of death or sustained VT or VF in patients receiving CRT-D vs. ICD in the MADIT-RIT trial.

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Background: Limited data exist regarding the proarrhythmic effects of smoking.

Objective: To evaluate the relationship between smoking and the risk of first and recurrent ventricular tachyarrhythmias (VTAs) in patients with mild heart failure.

Methods: The risk of a first and recurrent appropriate implantable cardioverter-defibrillator therapy for VTAs or death was compared between nonsmokers (n = 465), past smokers (n = 780), and current smokers (n = 197) in patients with ischemic and nonischemic cardiomyopathy who were enrolled in the Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy study.

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Background: There is a relative paucity of studies investigating the mechanisms of syncope among heart failure patients with implantable cardioverter-defibrillators, and it is controversial whether nonarrhythmogenic syncope is associated with increased mortality.

Methods And Results: The Multicenter Automatic Defibrillator Implantation Trial-Reduce Inappropriate Therapy (MADIT-RIT) randomized 1500 patients to 3 different implantable cardioverter-defibrillator programming arms: (1) Conventional programming with therapy for ventricular tachycardia ≥170 bpm; (2) high-rate cutoff with therapy for ventricular tachycardia ≥200 bpm and a monitoring zone at 170 to 199 bpm, and (3) prolonged 60-second delay with a monitoring zone before therapy. Syncope was a prespecified safety end point that was adjudicated independently.

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Objective: The aim of the present study was to assess a possible association between myocardial substrate, implantable cardioverter defibrillator (ICD) shocks, and subsequent mortality.

Methods: Within the multicentre automatic defibrillator implantation trial-cardiac resynchronization therapy (MADIT-CRT) population (n = 1790), we investigated the association between myocardial substrate, ICD shocks and subsequent mortality using multivariate Cox regression analyses and landmark analyses at 1-year follow-up.

Results: The 4-year cumulative probability of ICD shocks was 13% for appropriate shock and 6% for inappropriate shock.

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Article Synopsis
  • - The study investigated how diabetes mellitus influences the risk of receiving inappropriate or appropriate therapy in patients with implantable cardioverter-defibrillators (ICDs), finding that innovative ICD programming methods can help reduce inappropriate therapy risks for both diabetic and non-diabetic patients
  • - Among the 1,483 participants, those with diabetes showed a lower chance of inappropriate therapy and a higher chance of appropriate therapy compared to non-diabetics, indicating diabetes may affect therapy outcomes
  • - Despite the benefits of innovative programming, diabetic patients experiencing inappropriate or appropriate therapy faced significantly higher mortality risks, highlighting the need for careful therapy management in this group
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Objectives: This study sought to compare the effects of metoprolol and carvedilol in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) study.

Background: The impact of beta-blockers in heart failure (HF) patients with devices is uninvestigated.

Methods: All patients receiving either metoprolol or carvedilol in the MADIT-CRT study were identified and compared.

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Background: The majority of implantable cardioverter defibrillators (ICDs) are dual-chamber devices, but studies on the frequency of inappropriate therapy in dual- versus single-chamber devices have shown conflicting results. The aim of this study is to determine whether implantation of dual-chamber ICD devices decrease the incidence of inappropriate therapy without an unacceptable increase in complications.

Methods: In the ICD arm of the MADIT-CRT study (N = 704), comparisons of single- versus dual-chamber ICD devices were investigated on the endpoints of inappropriate therapy (antitachycardia pacing [ATP] and shocks) and device- and procedure-related complications by use of multivariate Cox proportional hazard regression analysis (hazard ratio dual:single chamber) adjusting for relevant covariates.

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Background: The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study has previously demonstrated a beneficial effect of losartan compared to atenolol-based antihypertensive treatment in patients with essential hypertension and left-ventricular hypertrophy (LVH). However, patient age often influences the choice of antihypertensive drugs. Therefore, we investigated the influence of age on the effects of losartan versus atenolol-based antihypertensive treatment.

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