Twelve-year trends in unprotected left main coronary artery occlusion: insights from a real-world multicentre study.

AIMS: Acute myocardial infarction (AMI) resulting from unprotected left main coronary artery (LMCA) occlusion and subtotal occlusion is a life-threatening condition. Although AMI management has improved in the past two decades, there is limited information on recent trends in patient characteristics, management, and outcomes for acute unprotected LMCA-related AMI. This study aims to assess such trends over a 12 year period. METHODS AND RESULTS: This retrospective multicentre study includes patients with unprotected LMCA occlusion/subtotal occlusion admitted to three tertiary hospitals between 2008 and 2020. The patients were divided into two groups based on the chronology of presentation: a 'past group' (January 2008 to December 2014) and a 'contemporary group' (January 2015 to December 2020). The study compares clinical characteristics, management approaches, and outcomes between the two groups. The study includes 128 patients, with 51 (40%) in the 'past group' and 77 (60%) in the 'contemporary group'. Baseline risk factors did not show statistically significant differences between the two groups, except for hypertension (49% vs. 74%; P = 0.005). Chest pain was more frequent in the 'past group' (98% vs. 89%; P = 0.014), and a trend towards more cardiac arrests was observed in the 'contemporary group' (18% vs. 31%; P = 0.087). Revascularization type did not differ significantly (P = 0.419), but manual thrombectomy was less frequently used (41% vs. 23%; P = 0.032) and stent implantation showed a trend towards higher rates (66% vs. 78%; P = 0.150) in the 'contemporary cohort'. There was a gradual shift from bare-metal to drug-eluting stents, with a significantly higher percentage of ticagrelor/prasugrel loading in the 'contemporary cohort' (5% vs. 79%; P < 0.001). The use of mechanical circulatory support (MCS), although not statistically significant, was higher among patients in the 'past group' (67% vs. 51%; P = 0.073). The type of MCS differed significantly between groups, with a decrease in intra-aortic balloon pump use (67% vs. 42%; P = 0.005) and an increase in veno-arterial extracorporeal membrane oxygenation (4% vs. 22%; P = 0.005) and Impella system (0% vs. 3%) over time. Survival analysis showed no significant differences (P = 0.599; log-rank test) in all-cause mortality between the different time groups, with the long-term survival rate being approximately 30%. CONCLUSIONS: In our real-world population, despite the progressive use of newer drugs and more advanced devices over time, patients with unprotected LMCA occlusion/subtotal occlusion remain a subpopulation with poor prognosis.

A report on a survey among Portuguese Association of Interventional Cardiology associates regarding ionizing radiation protection practices in national interventional cath-labs.

INTRODUCTION AND OBJECTIVES: Concerns surrounding the consequences of ionizing radiation (IR) have increased in interventional cardiology (IC). Despite this, the ever-growing complexity of diseases as well as procedures can lead to greater exposure to radiation. The aim of this survey, led by Portuguese Association of Interventional Cardiology (APIC), was to evaluate the level of awareness and current practices on IR protection among its members. METHODS: An online survey was emailed to all APIC members, between August and November 2021. The questionnaire consisted of 50 questions focusing on knowledge and measures of IR protection in the catheterization laboratory. Results were analyzed using descriptive statistics. RESULTS: From a response rate of 46.9%, the study obtained a total sample of 159 responses (156 selected for analysis). Most survey respondents (66.0%) were unaware of the radiation exposure category, and only 60.4% reported systematically using a dosimeter. A large majority (90.4%) employed techniques to minimize exposure to radiation. All participants used personal protective equipment, despite eyewear protection only being used frequently by 49.2% of main operators. Ceiling suspended shields and table protectors were often used. Only two-thirds were familiar with the legally established limit on radiation doses for workers or the dose that should trigger patient follow-up. Most of the survey respondents had a non-certified training in IR procedures and only 32.0% had attended their yearly occupational health consultation. CONCLUSIONS: Safety methods and protective equipment are largely adopted among interventional cardiologists, who have shown some IR awareness. Despite this, there is room for improvement, especially concerning the use of eyewear protection, monitoring, and certification.

Ticagrelor Loading on ST-Elevation Myocardial Infarction: Interaction With Prodromal Angina on Infarct Size and Clinical Events.

INTRODUCTION: Ticagrelor might reduce infarct size by exerting a more potent antiplatelet effect or by promoting a potential conditioning stimulus in ST-elevation myocardial infarction (STEMI) patients. Pre-infarction angina (PIA) is an effective preconditioning stimulus that reduces ischemia-reperfusion injury. Because little is known on the interaction of PIA in STEMI-patients loaded with ticagrelor, we sought to determine if patients loaded with ticagrelor had improved clinical outcomes as compared to clopidogrel and to study if it is modulated by the presence of PIA. METHODS: From 1272 STEMI patients submitted to primary percutaneous coronary intervention and treated with clopidogrel or ticagrelor from January 2008 to December 2018, 826 were analyzed after propensity score matching. Infarct size was estimated using peak creatine kinase (CK) and troponin T (TnT), and clinical impact was evaluated through cumulative major cardiac and cerebrovascular events (MACCE) at 1-year follow-up. Matched patients and their interaction with PIA were analyzed. RESULTS: Patients loaded with ticagrelor had lower peak CK [1405.50 U/L (730.25-2491.00), P < .001] and TnT [3.58 ng/mL (1.73-6.59), P < .001)], regardless of PIA. The presence of PIA was associated with lower CK (P = .030), but not TnT (P = .097). There was no interaction between ticagrelor loading and PIA (P = .788 for TnT and P = .555 for CK). There was no difference in MACCE incidence between clopidogrel or ticagrelor loading (P = .129). Cumulative survival was also similar between clopidogrel or ticagrelor, regardless of PIA (P = .103). CONCLUSION: Ticagrelor reduced infarct sizes independently and without a synergic effect with PIA. Despite reducing infarct size, clinical outcomes were similar across both groups.

Acute total occlusion of the unprotected left main coronary artery: Patient characteristics and outcomes.

INTRODUCTION AND OBJECTIVES: Acute total occlusion of the unprotected left main coronary artery (LMCA) is a dramatic event. There are limited data regarding this population. We aimed to describe the clinical presentation and outcomes of patients and to determine predictors of in-hospital mortality. METHODS: This retrospective study included patients presenting with acute (<12 h) myocardial infarction due to total occlusion of the LMCA (TIMI flow 0) between January 2008 and December 2020 in three tertiary hospitals. RESULTS: During this period, 11036 emergent coronary angiographies were performed, 59 (0.5%) of which revealed acute total occlusion of the LMCA. Patients' mean age was 61.2 (SD±12.2) years and 73% were male. No patients had left dominance. At presentation, 73% were in cardiogenic shock, aborted cardiac arrest occurred in 27% and 97% underwent myocardial revascularization. Primary percutaneous coronary intervention was performed in 90% of cases and angiographic success was achieved in 56% of procedures, while 7% of patients underwent surgical revascularization. In-hospital mortality was 58%. Among survivors, 92% and 67% were alive after one and five years, respectively. After multivariate analysis, only cardiogenic shock and angiographic success were independent predictors of in-hospital mortality. Use of mechanical circulatory support and presence of well-developed collateral circulation were not predictive of short-term prognosis. CONCLUSION: Acute total occlusion of the LMCA is associated with a dismal prognosis. Cardiogenic shock and angiographic success play a major role in predicting the prognosis of these patients. The effect of mechanical circulatory support on patient prognosis remains to be determined.

Coil Embolization for Management of Brachiocephalic Artery Perforation and Mediastinal Hematoma Following Percutaneous Coronary Intervention.

In this clinical image vignette, we illustrate the presentation and management of an extremely rare and lethal complica- tion of radial access percutaneous coronary intervention. We present a case of perforation of a small collateral branch of the brachiocephalic artery with subsequent mediastinal hematoma formation and stridor presentation. We suspect the perforation was probably caused by the hydrophilic-coated guidewire. After a multidisciplinary heart team discussion, a percutaneous approach was recommended. We performed the procedure with a single coil embolization of the collateral branch perforation, achieving complete resolution of the hemorrhage.

Temporary atrial septal defect balloon occlusion test as a must in the elderly.

BACKGROUND: Atrial septal defect (ASD) can often remain asymptomatic until adulthood. It still remains unclear whether large ASD closure in senior people should be performed or not. Temporary ASD balloon occlusion test has been suggested as a tool to assess the risk of acute left ventricular heart failure post-ASD closure, and it allows to better distinguish responders from non-responders. CASE PRESENTATION: An 83-year-old man with a long-standing uncorrected secundum ASD was admitted for recently decompensated right-sided heart failure. During hospitalization, this patient was studied with trans-esophageal echocardiography, cardiac magnetic resonance imaging, and right heart catheterization, showing high Qp:Qs ratio and favorable anatomical conditions for percutaneous closure. Because of patient's increasing need for intravenous diuretics and worsening renal function, it was considered that transcatheter ASD closure could improve symptoms, hence it was performed an attempt of percutaneous closure of the ASD with a fenestrated device. Unfortunately, irrespective of ASD being hemodynamically significant, it was found a very significant increase in pulmonary capillary wedge pressure during the temporary balloon occlusion test, supporting the existence of concealed left ventricular diastolic dysfunction. As a result, it was decided to abandon the procedure and not to close the ASD. CONCLUSION: This clinical case illustrates the value of temporary balloon occlusion test before permanent percutaneous closure of ASD in elderly patients, regardless of left ventricular (systolic or diastolic) dysfunction.

Atmospheric features and risk of ST-elevation myocardial infarction in Porto (Portugal): A temperate Mediterranean (Csb) city.

INTRODUCTION AND OBJECTIVES: Some atmospheric features have been linked to the triggering of myocardial infarction. Because data from the Temperate-Mediterranean is scarce, we sought to study whether meteorological parameters influence the incidence of ST-elevation myocardial infarction (STEMI) as confirmed by primary percutaneous intervention in a city with temperate weather (Porto, Portugal). METHODS: Retrospective analysis of a series of STEMI-patients from January 2010 to December 2017. Temperature (T), relative humidity (RH), precipitation, and atmospheric pressure were obtained from a government-led institute. We utilized a generalized linear model (GLM) with a Poisson distribution, where a series of models with multivariable analysis were computed. The effects (GLM coefficients) are presented as excess relative risk (ERR). RESULTS: One thousand and four consecutive STEMI-patients were included. The most important predictors of STEMI were Tmin two days before (for 1°C drop ERR=1.9%, p=0.009) and a 1% increase in RH three days before (EER=0.7%, p=0.006). Conversely, the same increase in RH the day before reduced the relative risk (EER=-0.6%, p=0.023). Temperature range, atmospheric pressure and precipitation had no impact on STEMI incidence. CONCLUSION: In a Temperate-Mediterranean city hot or cold temperature extremes, temperature drop and relative humidity had a significant impact on the occurrence of STEMI.

Platypnoea Orthodeoxia Syndrome and Patent Foramen Ovale Closure: Single-Centre Experience and Long-Term Follow-Up.

INTRODUCTION: Platypnoea orthodeoxia syndrome (POS) is an uncommon condition characterised by dyspnoea and arterial desaturation induced by an upright position and relieved in the supine position, usually due to a patent foramen ovale (PFO). Percutaneous closure of a PFO is the preferred treatment to cure POS. This study aimed to evaluate the clinical and gasometrical characteristics and to describe the long-term outcomes of percutaneous PFO closure in a group of patients with POS. METHODS: Patients with POS and a PFO treated by percutaneous intervention from 2010-2020 were reviewed. The primary efficacy outcome was the arterial oxygen pressure to fraction of inspired oxygen (PaO2/FiO2) ratio before and 24 hours after the procedure. Total clinical success was considered if the arterial oxygen saturation measured by pulse oximetry (SpO2) improved to >94% in the supine and sitting positions without supplemental oxygen, while partial success was considered if SpO2 improved from baseline but still required oxygen to achieve >94%. Secondary outcomes were an absolute improvement in SpO2 and sense of dyspnoea, without significant residual shunt on transthoracic echocardiography (TTE) at follow-up. RESULTS: Of 168 patients undergoing PFO or atrial septal defect closure, 14 had POS (8.3%). Percutaneous PFO closure was successfully performed in all patients with a single device. Twelve of 14 patients had total clinical success (86%) and one patient had partial success. The PaO2/FiO2 ratio increased from 155.9±50.6 to 318.3±73.4 after PFO closure (p=0.002). All patients with total clinical success had a successful secondary efficacy outcome with an absolute improvement in SpO2 and complete resolution of dyspnoea, which was maintained at follow-up (37±20 months; range, 11 months to 6 years). None had a significant residual shunt between 12 and 24 months of follow-up. CONCLUSION: The PFO percutaneous closure was a successful, durable and safe method for patients presenting with POS; it achieved major improvements in both gasometrical parameters and quality of life.

Myocardial Bridging Leading to Cardiac Collapse in a Marathon Runner.

Myocardial bridging (MB) is a congenital coronary anomaly, which is defined as cardiac muscle overlying a portion of a coronary artery. Although traditionally considered benign in nature, increasing attention is being given to specific subsets of MB. Sports medicine recognizes MB as a cause of sudden death among young athletes. We present a case of a 30-year-old man who suddenly collapsed during a marathon running. Diagnostic workup with coronary computed tomography angiography revealed the presence of three simultaneous myocardial bridges in this patient, possibly explaining the exercise-induced syncope. The other diagnostic tests excluded seizures, cranioencephalic lesions, ionic or metabolic disturbances, acute coronary syndromes, cardiomyopathies, myocarditis, or conduction disturbances. Exertional syncope is a high-risk complaint in the marathon runner. In the context of intense physical activity, the increased sympathetic tone leading to tachycardia and increased myocardial contractility facilitates MB ischemia. In this illustrative case, the patient's syncope might probably be associated with an ischemia-induced arrhythmia secondary to MB and potentiated by dehydration in the context of prolonged stress (marathon running). In conclusion, this case highlights that MB may be associated with dangerous complications (myocardial ischemia and life-threatening ventricular arrhythmias), particularly during intense physical activity and in the presence of a long myocardial bridge.

Successful Percutaneous Management of Iatrogenic Left Main Coronary Artery and Ascending Aorta Dissection.

Iatrogenic left main coronary artery and aortic root dissection is a rare but life-threatening complication of percutaneous coronary intervention. This is a case where this complication was induced by catheter manipulation. Prompt percutaneous closure of the dissection point of entry was effective in managing this complication. (Level of Difficulty: Advanced.).

Predictors and mid-term outcomes of nosocomial infection in ST-elevation myocardial infarction patients treated by primary angioplasty.

BACKGROUND: Nosocomial infections (NI) are associated with high morbidity and mortality. Existing data on the impact of NI on patients with ST-elevation myocardial infarction (STEMI) is scarce. AIM: Our aim was to determine the incidence, predictors, and prognosis of NI in a contemporary series of STEMI patients. METHODS: 1131 consecutive STEMI patients treated by primary percutaneous coronary intervention from January 2008 to December 2017 were analyzed. Binary logistic regression and Cox proportional hazard models were used to identify predictors of NI and major adverse cardio-cerebrovascular events (MACCE) at 1-year follow-up, respectively. RESULTS: Of all patients, 126 (11.1%) were diagnosed with NI (>48 hours from admission), mostly of respiratory (50.8%) and urinary (39.7%) tract origin. Insulin-treated diabetics were 3-fold more likely to develop NI. Other independent predictors were peripheral arterial disease, intra-aortic balloon pump insertion, age, lower systolic blood pressure, and higher peak creatine-kinase. Only pre-infarction angina was negatively related to NI. Age, peripheral arterial disease, femoral approach and larger infarct were related to MACCE at 1-year follow-up. NI in isolation was not independently related to MACCE (hazard ratio [HR], 1.24; 95% confidence interval [CI], 0.80-1.94; P = 0.34). However, we found a significant interaction between NI and smoking (HR, 2.33; 95% CI, 1.03-5.24; Pinterc = 0.04). CONCLUSION: Larger infarct size, hemodynamic instability, and co-morbidities were related to both NI and 1-year adverse events. Smokers who developed NI also had a higher 1-year risk of MACCE.

Contemporary management of severe symptomatic bicuspid aortic valve stenosis: the BiTri Registry.

AIMS: A greater number of patients with bicuspid aortic valves (BAV) may be identified and treated as indications for transcatheter aortic valve implantation (TAVI) are expected to expand to younger patients. We evaluated the contemporary frequency and management of symptomatic patients with stenotic BAV in a multicenter European registry. METHODS: Between November 2017 and February 2018, all consecutive patients admitted for symptomatic aortic stenosis across six high-volume European hospitals were prospectively enrolled in the BiTri registry. RESULTS: Of the 832 patients, 17% (n = 138) had a BAV. The most frequent BAV phenotypes were type 1 (left--right coronary cusps fusion 64%) and type 1 (right-noncoronary cusps fusion 17%). Type 0 and type 2 accounted for 12 and 2%, respectively. When compared with tricuspid patients (n = 694), BAV patients were younger, with lower surgical risk. The transthoracic echocardiography (TTE) identified BAV in 64% of patients. Multisliced computed tomography (MSCT) additionally completed the diagnosis in 20% of patients. Surgical inspection finally identified the remaining undiagnosed 16% of BAV. A combination of TTE and MSCT was the most common diagnosis method for BAV. Surgical aortic valve replacement (SAVR) was the predominant therapeutic option for BAV (70%) whilst TAVI was performed in 26%. CONCLUSION: BAV is frequently observed in symptomatic patients with aortic stenosis. These patients are younger, have a lower risk profile and are predominantly treated with SAVR as compared with tricuspid patients. However, TAVI is performed in almost one-third of BAV patients in contemporary European practice. TTE combined with MSCT identified 84% of BAV.

Pre-infarction angina is associated with improved prognosis in diabetic patients with ST-elevation myocardial infarction - data from a contemporary cohort.

BACKGROUND: Pre-infarction angina (PIA) is associated with improved prognosis in patients with ST-elevation myocardial infarction (STEMI). Some studies suggest that diabetes may blunt the effect of ischaemic preconditioning. We sought to study the impact of PIA in diabetic patients with STEMI. METHODS: Consecutive patients with STEMI who underwent primary angioplasty were included. PIA was defined as ≥1 episode of chest pain during the week preceding STEMI diagnosis. Incident major adverse cardiovascular events (MACE) were defined as the first occurrence of all-cause death, stroke or acute myocardial infarction. RESULTS: Of the 1143 included patients, 25% were diabetic and 32% had a history of PIA. Diabetic patients with PIA had smaller infarct sizes as estimated by peak creatine kinase (CK) [1144 (500-2212) vs. 1715 (908-3309) U/L, P = 0.003] and peak troponin [3.30 (1.90-6.58) vs. 4.88 (2.50-9.58) ng/ml, P = 0.002], compared to diabetics without PIA. They also had a lower likelihood of evolving with moderate to severe reduced left ventricle ejection fraction (LVEF) (25.6%, n = 22 vs. 46.6%, n = 82, P = 0.001). In non-diabetic patients, PIA was associated with reduced peak CK [1549 (909-2909) vs. 1793 (996-3078), P = 0.0497], but not troponin (3.74 [2.23-7.11] vs. 4.56 [2.44-7.77] ng/ml, P = 0.19), and was not associated with reduced LVEF (32.0%, n = 85 vs. 37.4%, n = 207, P = 0.13). Both diabetic and non-diabetic patients with PIA had a lower likelihood of evolving with a Killip class III/VI (non-diabetic patients: 5.6% vs. 14.1%, P = 0.002; diabetic patients: 12.8% vs. 24.6%, P = 0.049). Over a median follow-up of 18.0 (12.1-25.5) months, PIA was associated with a significant reduction in the incidence of MACE [hazard ratio 0.52, 95% confidence interval (CI) 0.37-0.74, P < 0.001], irrespective of diabetes status. CONCLUSION: PIA is an independent predictor of favourable outcomes in the setting of STEMI for both diabetic and non-diabetic patients.

Incidence and outcome of peri-procedural transcatheter heart valve embolization and migration: the TRAVEL registry (TranscatheteR HeArt Valve EmboLization and Migration).

AIMS: Peri-procedural transcatheter valve embolization and migration (TVEM) is a rare but potentially devastating complication of transcatheter aortic valve implantation (TAVI). We sought to assess the incidence, causes, and outcome of TVEM in a large multicentre cohort. METHODS AND RESULTS: We recorded cases of peri-procedural TVEM in patients undergoing TAVI between January 2010 and December 2017 from 26 international sites. Peri-procedural TVEM occurred in 273/29 636 (0.92%) TAVI cases (age 80.8 ± 7.3 years; 53.8% female), of which 217 were to the ascending aorta and 56 to the left ventricle. The use of self-expanding or first-generation prostheses and presence of a bicuspid aortic valve were independent predictors of TVEM. Bail-out measures included repositioning attempts using snares or miscellaneous tools (41.0%), multiple valve implantations (83.2%), and conversion to surgery (19.0%). Using 1:4-propensity matching, we identified a cohort of 235 patients with TVEM (TVEMPS) and 932 patients without TVEM (non-TVEMPS). In the matched cohort, all-cause mortality was higher in TVEMPS than in non-TVEMPS at 30 days (18.6% vs. 4.9%; P < 0.001) and after 1 year (30.5% vs. 16.6%; P < 0.001). Major stroke was more frequent in TVEMPS at 30 days (10.6% vs. 2.8%; P < 0.001), but not at 1 year (4.6% vs. 1.9%; P = 0.17). The need for emergent cardiopulmonary support, major stroke at 30 days, and acute kidney injury Stages 2 and 3 increased the risk of 1-year mortality, whereas a better renal function at baseline was protective. CONCLUSION: Transcatheter valve embolization and migration occurred in approximately 1% and was associated with increased morbidity and mortality.

How to Make the TAVI Pathway More Efficient.

Transcatheter aortic valve implantation (TAVI) has been in use for 16 years. As there has been a rapid expansion in its use, there is a need to optimise TAVI programmes to ensure efficiency. In this article, the authors discuss the reasons why clinicians need to make the TAVI pathway more efficient and describe the most important steps to take from screening to early discharge, including procedural optimisation.

The impact of preinfarct angina on the incidence of acute kidney injury in patients with myocardial infarction: interaction with pre-existent chronic kidney disease.

AIM: Remote ischemic conditioning may reduce acute kidney injury (AKI) in patients undergoing a coronary intervention. As preinfarct angina (PIA) might act as a preconditioning stimulus in patients with ST-elevation myocardial infarction (STEMI), we aimed to study whether PIA reduces AKI in accordance to pre-existing chronic kidney disease. PATIENTS AND METHODS: We conducted a retrospective study including 891 consecutive STEMI patients who underwent primary coronary intervention from January 2008 to March 2016. AKI was determined on the basis of KDIGO criteria. The impact of PIA was evaluated in three groups according to the baseline glomerular filtration rate: less than 45 ml/min/1.73 m (group 1, n = 89), 45-59 ml/min/1.73 m (group 2, n = 117), and greater than or equal to 60 ml/min/1.73 m (group 3, n = 642). Univariate and multivariate predictors for AKI were determined. RESULTS: AKI developed in 13.8% of patients (n = 117) and was more prevalent in patients with worse baseline renal function (35% in group 1; 22% in group 2; and 9% in group 3, P < 0.01). The prevalence of PIA was similar across groups (28-34%, P = 0.2). Only in group 1 did patients with PIA have a significantly lower rate of AKI than patients without PIA (19 vs. 42%, P = 0.033). In multivariate analysis, the absence of PIA in group 1 patients conferred an almost three-fold risk of developing AKI (odds ratio = 2.92, P = 0.009), whereas no differences were found for the other groups. Age, total ischemic time, and intra-aortic balloon pump utilization were also related independently to AKI. CONCLUSION: In our series, STEMI patients with at least stage 3B chronic kidney disease had a three-fold risk of developing AKI in the absence of PIA. These findings suggest that patients with worse renal function may be more susceptible to the renoprotective effect of myocardial ischemic preconditioning.

The Stent for Life initiative: Factors predicting system delay in patients with ST-segment elevation myocardial infarction.

INTRODUCTION AND AIMS: System delay (time between first medical contact and reperfusion therapy) is an indicator of quality of primary percutaneous coronary intervention (pPCI) in ST-segment elevation myocardial infarction (STEMI) patients. This study aimed to assess changes in system delay between 2011 and 2015, and to identify its predictors. METHODS: The study included 838 patients admitted to 18 Portuguese interventional cardiology centers suspected of having STEMI with less than 12 hours' duration who were referred for primary percutaneous coronary intervention. Data were collected for a one-month period every year from 2011 to 2015. Univariate and multivariate logistic regression models were used to determine predictors of system delay. RESULTS: No significant changes in system delay were observed during the study. Only 27% of patients had a system delay of ≤90 min. Multivariate analysis identified four predictors of system delay: age ≥75 years (OR 2.57; 95% CI 1.50-4.59; p=0.001), attending a center without pPCI (OR 4.08; 95% CI 2.75-6.10; p<0.001), not calling the national medical emergency number (112) (OR 0.47; 95% CI 0.32-0.68; p<0.001), and Central region (OR 3.43; 95% CI 1.60-8.31; p=0.003). CONCLUSIONS: The factors age ≥75 years, attending a center without pPCI, not calling 112, and Central region were identified as predicting longer system delay. This knowledge may help in planning interventions to reduce system delay and to improve the clinical outcomes of patients with STEMI.