ST-segment resolution after reperfusion therapy: can this predict the long-term effects of a heart attack?

This study investigated the long-term effects of ST-segment resolution after a heart attack.

They concluded that 

Coronary artery disease refers to blockages, or plaques, in vessels that supply blood to the heart. Following a heart attack (myocardial infarction), a procedure called reperfusion is performed. This involves administering drugs and/or performing surgery to remove a blockage in the vessel and restore blood flow.

Percutaneous coronary intervention (PCI) is a type of reperfusion therapy. Following a heart attack, a symptom called ‘ST-segment abnormalities’ can persist. This is an abnormality in the heart rhythm. Resolution of ST segment (STR) after therapy such as PCI is important to restore blood flow and heart function.

In some cases, ST segment abnormalities will not fully resolve and this may have long-term effects for the patient.

This study investigated if STR following PCI had any long-term implications on the survival of patients.

This study included 1351 patients who underwent PCI following a heart attack. The degree of STR was categorized as less than 50%, or less than 70%. Rates of death, heart attack or revascularization procedures (e.g. bypass surgery) after 5 years were measured. 

Patients without STR were more likely to have had a number of conditions including diabetes, previous stroke and high blood pressure. Patients with diabetes had a greater chance of less than 50% resolution (71% greater). Less than 50% and less than 70% STR increased the risk of negative outcomes such as death or heart attack. Less than 70% STR was a significant predictor of these outcomes.

The authors concluded that less than 50% and less than 70% resolution of ST-segment was associated with increased risk of heart attack and death.

This study was retrospective. As a result, patient care varied and data on drug treatment was not available for these participants. This may have an impact on the outcomes. Further investigation is needed.