Optimising the dichotomy limit for left ventricular ejection fraction in selecting patients for defibrillator therapy after myocardial infarction

TY - JOUR

T1 - Optimising the dichotomy limit for left ventricular ejection fraction in selecting patients for defibrillator therapy after myocardial infarction

AU - Yap, Yee Guan

AU - Duong, Trinh

AU - Bland, J Martin

AU - Malik, Marek

AU - Torp-Pedersen, Christian

AU - Køber, Lars

AU - Gallagher, Mark M

AU - Camm, A John

N1 - Keywords: Aged; Arrhythmias, Cardiac; Cost-Benefit Analysis; Defibrillators, Implantable; Female; Humans; Male; Multicenter Studies as Topic; Myocardial Infarction; Patient Selection; Prospective Studies; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Stroke Volume

PY - 2007

Y1 - 2007

N2 - BACKGROUND: The selection of patients for prophylactic implantable cardioverter-defibrilator (ICD) treatment after myocardial infarction (MI) remains controversial. AIM: To determine the optimum left ventricular ejection fraction (LVEF) dichotomy limit for ICD treatment in patients with a history of MI. METHODS AND RESULTS: Data from the placebo arms of four randomised trials were pooled to create a cohort of 2828 patients (2206 men, mean (SD) age 65 (11) years) with reduced left ventricular function after MI. The median LVEF was 33% (range 6-40%). LVEF significantly predicted mortality. Each 10% reduction in LVEF <40% conferred a 42% increase in all-cause mortality, a 39% increase in arrhythmic cardiac mortality and a 49% increase in non-arrhythmic cardiac mortality over the 2-year period of follow-up (p<0.001 for all modes of mortality). As the LVEF progressively decreased from < or =40% to < or =10%, the data show a U-shaped relationship between the dichotomy limit for LVEF used and the number of patients who must be treated to prevent one arrhythmic death in 2 years. At an LVEF of 16-20%, more patients are likely to die from arrhythmic than non-arrhythmic cardiac deaths, whereas in those with LVEF < or =10% all deaths were non-arrhythmic. However, the total number of deaths substantially decreased with lower LVEF. CONCLUSION: A trade-off exists between the sensitivity and positive predictive accuracy across a range of LVEF, and no single dichotomy limit is completely satisfactory. In patients with LVEF < or =10% ICD treatment was not beneficial as all patients in this subgroup died from non-arrhythmic causes. The use of a single dichotomy limit for LVEF alone is not sufficient in selecting patients for ICD treatment in the primary prevention of cardiac arrest.

AB - BACKGROUND: The selection of patients for prophylactic implantable cardioverter-defibrilator (ICD) treatment after myocardial infarction (MI) remains controversial. AIM: To determine the optimum left ventricular ejection fraction (LVEF) dichotomy limit for ICD treatment in patients with a history of MI. METHODS AND RESULTS: Data from the placebo arms of four randomised trials were pooled to create a cohort of 2828 patients (2206 men, mean (SD) age 65 (11) years) with reduced left ventricular function after MI. The median LVEF was 33% (range 6-40%). LVEF significantly predicted mortality. Each 10% reduction in LVEF <40% conferred a 42% increase in all-cause mortality, a 39% increase in arrhythmic cardiac mortality and a 49% increase in non-arrhythmic cardiac mortality over the 2-year period of follow-up (p<0.001 for all modes of mortality). As the LVEF progressively decreased from < or =40% to < or =10%, the data show a U-shaped relationship between the dichotomy limit for LVEF used and the number of patients who must be treated to prevent one arrhythmic death in 2 years. At an LVEF of 16-20%, more patients are likely to die from arrhythmic than non-arrhythmic cardiac deaths, whereas in those with LVEF < or =10% all deaths were non-arrhythmic. However, the total number of deaths substantially decreased with lower LVEF. CONCLUSION: A trade-off exists between the sensitivity and positive predictive accuracy across a range of LVEF, and no single dichotomy limit is completely satisfactory. In patients with LVEF < or =10% ICD treatment was not beneficial as all patients in this subgroup died from non-arrhythmic causes. The use of a single dichotomy limit for LVEF alone is not sufficient in selecting patients for ICD treatment in the primary prevention of cardiac arrest.

U2 - 10.1136/hrt.2006.102186

DO - 10.1136/hrt.2006.102186

M3 - Journal article

C2 - 17237132

SN - 1355-6037

VL - 93

SP - 832

EP - 836

JO - Heart

JF - Heart

IS - 7

ER -