Aim
The no-or-slow-reflow phenomenon after primary percutaneous coronary intervention is associated with more extensive myocardial injury in patients with ST-elevation myocardial infarction (STEMI). Soluble suppression of tumourigenicity 2 (sST2) is released in acute myocardial response to injury, and an increase in plasma level in the initial phase of STEMI is associated with increased mortality and risk of heart failure. We have therefore explored the association of pre-intervention plasma sST2 with the post-procedural no-or-slow-reflow phenomenon in patients with STEMI.

Methods and results
We included consecutive patients with verified STEMI from two tertiary heart centres. Blood samples were collected at admission before angiography. Post-procedural coronary flow was assessed according to thrombolysis in myocardial infarction (TIMI) classification for STEMI. Patients were divided into two groups: post-procedural TIMI 0–2 as no-or-slow reflow and TIMI 3 as normal reflow. The association between sST2 and TIMI flow was explored using multiple logistic regression. A total of 1607 patients with available TIMI flow classification were included in the analysis. Normal reflow was seen in 1520 (94.6%), while 87 (5.4%) had no-or-slow reflow. No-or-slow-reflow patients had higher all-cause 30-day mortality [10 (11%) vs. 65 (4.3%), P = 0.006]. Pre-procedural sST2 was higher in the no-or-slow-flow group [47 ng/mL, interquartile range (IQR, 33–83) vs. 39 ng/mL (IQR 29–55), P < 0.001] and was independently associated with post-procedural no-or-slow flow [two-fold sST2 increase: odds ratio 1.44 (1.15–1.78), P = 0.0012].

Conclusion
In patients with STEMI, the sST2 level at admission before coronary angiography is independently associated with the post-procedural no-or-slow-reflow phenomenon.