There are conflicting data on the clinical outcomes of percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) based on the time of admission to the catheterization laboratory. Thus, we aimed to assess clinical outcomes in an unselected cohort of consecutive patients with STEMI treated with PCI during on- and off-hours of work. A total of 99,783 patients were included in the analysis. Patients were divided using the most frequently used definition: On-hours (Monday-Friday 07:00 AM-04:59 PM); off-hours (Monday-Friday 05:00 PM-06:59 AM, Saturday, Sunday and nonworking Holidays)(37,469 matched pairs) To avoid potential preselection bias, a propensity score was calculated to compare on- and off-hours group. Higher radiation doses were observed for PCIs performed during off-hours (1055.2(±1006.5) vs. 1081.6(±1003.25)[mGy], p=0.001). A similar prevalence of periprocedural complications was observed during on- and off-hours. However, there was a higher mortality rate during off-hours compared to regular working hours ( 1.17% (439) vs. 1.49% (559), p=0.001). Primary PCIs in STEMI performed during off-hours might be associated with a higher rate of periprocedural mortality and higher radiation doses than procedures conducted during regular working hours.

Myocardial infarction (MI) with non-obstructive coronary arteries (MINOCA) is an important clinical problem especially in the era of extensive utilization of coronary angiography in MI patients. Its pathophysiology is poorly understood which makes diagnostics and treatment of MINOCA challenging in everyday clinical practice. The aim of the study was to assess characteristics of MINOCA patients in Poland based on data from the Polish National ORPKI Registry. In 2016, 49,893 patients with non-ST-segment elevation (NSTEMI) or ST-segment elevation (STEMI) myocardial infarction entered the ORPKI registry. MINOCA was defined as a non-obstructive coronary artery disease (CAD) and a lack of previous coronary revascularization. MINOCA was identified in 3924 (7.8%) patients and clinical presentation was more often NSTEMI than STEMI (MINOCA: 78 vs. 22%; obstructive CAD 51.1 vs. 48.9%; p < 0.0001). MINOCA patients were younger and more often females with significantly lower rates of diabetes, smoking, arterial hypertension, kidney disease, previous MI and previous stroke comparing to patients with obstructive CAD. Myocardial bridge was visualized in angiography more often in the MINOCA group (2.2 vs. 0.4%; p < 0.0001). Additional coronary assessment inducing fractional flow reserve, intravascular ultrasound, optical coherence tomography was marginally (< 1%) used in both groups. Periprocedural mortality was lower in MINOCA group (0.13% vs. 0.95%; p < 0.0001). MINOCA patients represent a significant proportion of MI patients in Poland. Due to multiple potential causes, MINOCA should be considered rather as a working diagnosis after coronary angiography and further efforts should be taken to define the cause of MI in each individual patient.

We sought to evaluate the impact of experience and proficiency with radial approach (RA) on clinical outcomes of percutaneous coronary interventions (PCI) performed via femoral approach (FA) in the “real-world” national registry. A total of 539 invasive cardiologists performing PCIs in 151 invasive cardiology centers in Poland between 2014 and 2017 were included. Proficiency threshold was set at >300 PCIs during four consecutive years per individual operator. The majority of operators performed >75% of all PCIs via RA (449 (65.4%)), 143 (20.8%) in 50–75% of cases, 62 (9.0%) in 25–50% and only 33 (4.8%) invasive cardiologists were using RA in <25% of all PCIs. Operators with the highest proficiency in RA were associated with increased risk of periprocedural death, stroke and bleeding complications at access site during angiography via FA. Similarly, higher prevalence of periprocedural mortality during PCI with FA was observed in most experienced radial operators as compared to other groups. The detrimental effect of FA utilization by the most experienced radial operators was observed in both stable angina and acute coronary syndromes. Higher experience and utilization of RA might be linked to worse outcomes of PCIs performed via femoral artery in both stable and acute settings.