Abstract 2492: Impact of Circadian Rhythm of STEMI Onset on the Myocardial Tissue-reperfusion after Primary PCI
Plaque rapture adds to the pathomechanism of STEMI in 50% of cases. Its occurrence was shown to predict no-reflow. Interestingly, STEMI that onset between 6a.m. and 12p.m. are more often triggered by plaque rupture. Whether the time of STEMI onset influences myocardial tissue-reperfusion after primary PCI is unknown.
Methods. In 431 consecutive pts (59.9±11.7yrs, 73% males) treated within the 12h from the pain-onset, diagnostic and postprocedural ECGs were analysed. Pts were categorized into the 4 groups depending on the time of the STEMI onset. Unsuccessful myocardial tissue-reperfusion was defined as the % resolution of the initial sum of ST-elevation&depression of <50%.
Results. In 36.2% of pts, STEMI onset in the morning (6a.m.-12p.m). Overall, unsuccessful myocardial tissue reperfusion was identified in 31.8% of subjects. Except shorter time-to-treatment in pts with STEMI onset in the morning (3.9±2.4h vs. 6.3±6.0h in other, p<0.001), studied groups did not differ with regard to the demographics and baseline clinical characteristic. Unsuccessful myocardial tissue-reperfusion occurred more frequently in pts with the STEMI onset between 6a.m.-12p.m. (44.9% vs. 24.4% in other, p<0.001, Table⇓).
Conclusions. Despite comparable baseline clinical characteristics and even shorter time-to-treatment, patients with STEMI onset in the morning had more frequently unsuccessful myocardial tissue-reperfusion after primary PCI. Suspected occurrence of plaque rupture is likely explanation of phenomenon.