Survival after withdrawal of dofetilide in patients with congestive heart failure and a short baseline QTc interval; a follow-up on the Diamond-CHF QT substudy

TY - JOUR

T1 - Survival after withdrawal of dofetilide in patients with congestive heart failure and a short baseline QTc interval; a follow-up on the Diamond-CHF QT substudy

AU - Brendorp, B

AU - Torp-Pedersen, C

AU - Elming, H

AU - Køber, L

N1 - Keywords: Adult; Aged; Anti-Arrhythmia Agents; Double-Blind Method; Female; Follow-Up Studies; Heart Failure; Humans; Infant, Newborn; Long QT Syndrome; Male; Middle Aged; Phenethylamines; Proportional Hazards Models; Risk Factors; Sulfonamides; Survival Analysis; Treatment Outcome; Ventricular Dysfunction, Left

PY - 2003

Y1 - 2003

N2 - BACKGROUND: We have previously observed dofetilide to be associated with improved survival when the pre-treatment baseline QTc interval was below 429 ms. In this study we tested the natural extension of this observation-that the same group of patients should have a loss of survival benefit after withdrawal of dofetilide. METHODS: Patients with congestive heart failure (CHF) and reduced left ventricular function enrolled in the Diamond-CHF (Danish Investigations of Arrhythmia and Mortality on Dofetilide-CHF) study were eligible for our QT substudy provided they were in sinus rhythm and had a measurable QTc interval from a 12-lead standard ECG taken before randomization to placebo or dofetilide. An extended follow-up was performed from study closure, December 1996 until August 2001. RESULTS: Of the 418 patients entering the extended follow-up, 215 (51%) patients died during this 4.5 years of additional observation time. The baseline QTc interval made no prognostic difference to mortality in placebo treated patients. For dofetilide treated patients with a baseline QTc interval <429 ms, increased mortality was observed during the extended follow-up compared to placebo (risk ratio 1.5, 95% confidence interval 1.1-2.8)[corrected]. CONCLUSIONS: This follow-up study shows significant loss of survival benefit upon withdrawal of dofetilide in patients with CHF and a pre-treatment QTc interval below 429 ms. An independent randomized trial is warranted to validate these results.

AB - BACKGROUND: We have previously observed dofetilide to be associated with improved survival when the pre-treatment baseline QTc interval was below 429 ms. In this study we tested the natural extension of this observation-that the same group of patients should have a loss of survival benefit after withdrawal of dofetilide. METHODS: Patients with congestive heart failure (CHF) and reduced left ventricular function enrolled in the Diamond-CHF (Danish Investigations of Arrhythmia and Mortality on Dofetilide-CHF) study were eligible for our QT substudy provided they were in sinus rhythm and had a measurable QTc interval from a 12-lead standard ECG taken before randomization to placebo or dofetilide. An extended follow-up was performed from study closure, December 1996 until August 2001. RESULTS: Of the 418 patients entering the extended follow-up, 215 (51%) patients died during this 4.5 years of additional observation time. The baseline QTc interval made no prognostic difference to mortality in placebo treated patients. For dofetilide treated patients with a baseline QTc interval <429 ms, increased mortality was observed during the extended follow-up compared to placebo (risk ratio 1.5, 95% confidence interval 1.1-2.8)[corrected]. CONCLUSIONS: This follow-up study shows significant loss of survival benefit upon withdrawal of dofetilide in patients with CHF and a pre-treatment QTc interval below 429 ms. An independent randomized trial is warranted to validate these results.

M3 - Journal article

C2 - 12590905

SN - 0195-668X

VL - 24

SP - 274

EP - 279

JO - European Heart Journal

JF - European Heart Journal

IS - 3

ER -