Risk markers of complications of acute myocardial infarction in long-term follow-up depending on the age of patients
- State Institution «National Science Center «Institute of Cardiology the name of academician M.D. Strazheskaya» NAMS of Ukraine», Kyiv
Summary. The aim is to identify risk markers for complications of acute myocardial infarction (AMI) in long-term follow-up, depending on the age of the patients. Object and research methods. The data of remote monitoring of patients hospitalized with a diagnosis of «Acute coronary syndrome with ST segment elevation» and undergoing treatment in the intensive care unit were analyzed. Depending on age, patients are divided into two groups: 1-st (n=160) — <45, 2-nd (n=457) — ≥45 years. The mean follow-up was 4.89±2.66 years. We evaluated the death rate from any causes within 5 years of observation, the development of a combined endpoint (CEP), cardiovascular death (CVD)/AMI/stroke over 5 and 10 years. Results. Patients of the 1st group had significantly better survival during 10 years of observation than the 2nd (Log-rank test — LRT; p=0.027). The difference in the curves was determined after the 1-st year of observation (LRT; p=0.031), as well as after 3; 5 and 10 years. CVD or repeated AMI was also more often observed in patients of the 2-nd group (LRT; p=0.021). Patients aged <35 years showed better survival rates among the studied subgroups; with increasing age, the frequency of complications increased. Arterial hypertension is the main risk factor for the development of long-term complications in young patients (relative risk 4.0; 95% confidence interval 1.5–10.7; p=0.006). Patients with a low left ventricular ejection fraction (LV EF) (<40%) on the 1-st day after AMI had a high probability of death from any causes within 5 years of follow-up (relative risk 3.4; 95% confidence interval 1.2–2.05; p=0.022). Patients who underwent myocardial revascularization during the first 3 years had significantly fewer ischemic complications (CVD/repeated AMI/stroke) (LRT; p=0.048). Findings. Patients of a young age (<45 years) with AMI are characterized by fewer complications during a long (<10 years) out-of-hospital observation period compared with the older age group. Among the risk factors for recurring cardiovascular events in these patients are concomitant arterial hypertension and LV dysfunction. However, reduced LVEF (<40%) upon admission was more important for the death within 5 years of observation, and maintaining values <50% on the 5–7-th day of the disease was important for the development of CEP. Myocardial revascularization (thrombolysis or primary percutaneous intervention) reduces the risk of developing CEP only during the first 3 years of observation, then its positive value is lost. The absence of hemodynamically significant stenosis of the coronary arteries according to coronary ventriculography, the age <35 years and the timely conduct of drug or mechanical myocardial revascularization indicate a low risk of complications during prolonged observation.