Background: The aim of this study was to examine the prognostic value of several clinical characteristics on long-term mortality and causes of death after acute coronary syndrome.

Methods: The   ABC-2   study   is   a   prospective   investigation   comprising  557  patients  with  acute  coronary  syndrome.  During  hospitalization,   33   clinical   variables,   including   demographics,   cardiovascular  risk  factors,  in-hospital  characteristics,  and  blood  components, were examined. “Acute models” were survival models containing  the  variables  accrued  within  72  h  from  admission,  and  “sub-acute  models”  contained  data  accrued  over  a  7-day  period.  Cox regression models were used for the survival analysis.

Results: The  12-year  follow-up  study  revealed  that  51.2%  of  the  patients  died  (15.8%  of  the  patients  died  from  coronary  artery  disease  and/or  heart  failure,  12.6%  of  the  patients  experienced  sudden death, 8.3% of the patients died from other-cardiovascular diseases, and 14.5% of the patients died from non-cardiovascular causes. The following factors were independently associated with all-cause  mortality  in  both  the  acute  and  sub-acute  models:  age,  left ventricular ejection fraction (negative), body mass index (non-linear),  previous  myocardial  infarction,  diabetes  mellitus,  blood  glucose  (non-linear),  Killip  class>1,  albumin/creatinine  ratio,  and  pre-hospital  time  delay.  The  variables  associated  with  coronary  artery  disease  and/or  heart  failure  included  age,  left  ventricular  ejection fraction (negative), body mass index (non-linear), previous myocardial   infarction,   Killip   class>1,   albumin/creatinine   ratio,   and  pre-hospital  time  delay,  while  the  variables  associated  with  sudden  death  included  age,  hypertension  (negative),  uric  acid,  left  ventricular  ejection  fraction  (negative),  and  pre-hospital  time  delay,  and  those  associated  with  other-  cardiovascular  causes  included age, hypertension, and albumin/creatinine ratio. The only variable associated with non- cardiovascular mortality was age. The C-statistic of the predictive models was 0.86 for all-cause mortality, whereas the C-statistic ranged from 0.74 to 0.80 for cardiovascular causes.

Conclusions: The  ABC-2  study  revealed  clinical  predictors  of long-term  mortality  after  acute  coronary  syndrome  that  might  help  prognostication,  patient  education,  and  risk  modification. Furthermore,  the  results  showed  that  the  modes  of  death  are  independently associated with different baseline clinical features.

Keywords: Acute coronary syndrome;  Mortality; Risk   prediction; Survival analysis