decompensated arrhythmia congestive heart failure uncontrolled ejection fraction absence left threatening maintenance arrhythmias ventricular infarction myocardial ongoing life congestive heart heart congestive failure symptomatic history chf disease active requiring arrhythmia threatening stroke cardiovascular arrhythmia unstable infarction myocardial life problems congestive heart arrhythmias cardiovascular disease class infarction myocardial congestive symptomatic significant coronary artery disease cardiac symptomatic heart failure congestive myocardial infarction cardiac heart significant arrhythmia myocardial failure infarction congestive disease clinically ischemia evidence symptomatic peripheral myocardial ecg cardiac arrhythmia significant muscle heart nyha controlled abnormalities york association arrhythmia infarction myocardial congestive