Author's Reply.

To the Editor,

We thank the authors for their comments about our article entitled “Admission serum potassium level is associated with in-hospital and

long-term mortality in ST-elevation myocardial infarction” published in Anatol J Cardiol 2015 Feb 11. (1). In the study, we conducted ST elevation myocardial infarction (STEMI) in patients undergoing primary percutaneous coronary intervention (PCI). An admission serum potassium (sK) level of >4.5 mmol/L was found to be associated with short- and long-term mortality (1).

Firstly, all patients in the study were treated with the dual antiplatelet therapy (clopidogrel 75 mg/day and acetylsalicylic acid 100 mg/day) for at least one year (1). Even though ticagrelor and prasugrel are associated with better results in patients with STEMI, during the period the study was conducted, neither prasugrel nor ticagrelor was administered in our center (2, 3). The effect of ticagrelor or prasugrel was not evaluated in our study.

The effect of aldosterone antagonists was not evaluated. The global left ventricular ejection fraction did not significantly differ between groups. Even though we did not evaluate the effect of aldosterone antagonists, in our opinion, this could not affect the outcome between the groups. However, cumulative end points will probably be affected. The effect of aldosterone antagonists could be a part of another study.

Thirdly, all patients with STEMI underwent primary PCI in our center regardless of the admission creatinine level. The patients’ blood at the time of admission was drawn at the emergency department without procedure delay. No significant correlation was found between admission sK level and door-to-balloon time (p=0.19).

In conclusion, despite the presence of many confounding factors, we thought that an sK level of >4.5 mmol/L is associated with short- and long-term mortality. The effect of aldosterone antagonists, prasugrel, and ticagrelor could be evaluated in different studies.