Absence of chest pain and long-term mortality in patients with acute myocardial infarction

Objective Chest pain is the predominant symptom in patients with acute myocardial infarction (AMI). A lack of chest pain in patients with AMI is associated with higher in-hospital mortality, but whether this outcome is sustained throughout the first years after onset is unknown. Therefore, we aimed to investigate long-term mortality in patients hospitalised with AMI presenting with or without chest pain. Methods All AMI cases registered in the SWEDEHEART registry between 1996 and 2010 were included in the study. In total, we included 172 981 patients (33.5% women) with information on symptom presentation. Results Patients presenting without chest pain (12.7%) were older, more often women and had more comorbidities, prior medications and complications during hospitalisation than patients with chest pain. Short-term and long-term mortality rates were higher in patients without chest pain than in patients with chest pain: 30-day mortality, 945 versus 236/1000 person-years; 5-year mortality, 83 versus 21/1000 person-years in patients <65 years. In patients ≥65 years, 30-day mortality was 2294 versus 1140/1000 person-years; 5-year mortality, 259 versus 109/1000 person-years. In multivariable analysis, presenting without chest pain was associated with an overall 5-year HR of 1.85 (95% CI 1.81 to 1.89), with a stronger effect in younger compared with older patients, as well as in patients without prior AMI, heart failure, stroke, diabetes or hypertension. Conclusion Absence of chest pain in patients with AMI is associated with more complications and higher short-term and long-term mortality rates, particularly in younger patients, and in those without previous cardiovascular disease.