ST-Elevation Myocardial Infarction remains one of the leading causes of cardiovascular morbidity and mortality worldwide despite major advances in preventive cardiology and reperfusion therapy. STEMI is characterized by acute coronary artery occlusion resulting from plaque rupture and thrombus formation, leading to prolonged myocardial ischemia and irreversible myocardial necrosis if prompt reperfusion is not achieved. Early restoration of coronary blood flow is therefore the cornerstone of management in order to preserve myocardial function, reduce infarct size, improve survival, and minimize complications such as heart failure, arrhythmias, and cardiogenic shock.⁽¹⁻³⁾ Primary percutaneous coronary intervention (PPCI) is currently considered the preferred reperfusion strategy for patients presenting with acute STEMI when it can be performed within the recommended time limits by experienced interventional cardiology teams. PPCI has demonstrated superiority over fibrinolytic therapy in reducing mortality, recurrent myocardial infarction, reinfarction, and intracranial hemorrhage.⁽⁴⁻⁶⁾ International guidelines from the European Society of Cardiology (ESC) and the American College of Cardiology/American Heart Association (ACC/AHA) strongly recommend PPCI as the first-line reperfusion modality when available within 120 minutes of first medical contact.⁽⁷,⁸⁾ Several factors influence the clinical outcomes of PPCI in STEMI patients, including total ischemic time, door-to-balloon time, operator experience, infarct location, thrombolysis in myocardial infarction (TIMI) flow grade, comorbidities, and the extent of coronary artery disease. Delays in reperfusion are associated with increased myocardial damage and worse prognosis.⁽⁹⁾ Consequently, rapid diagnosis and timely transfer to catheterization-capable centers are essential components of STEMI management systems. Recent advances in interventional cardiology, including improved stent technology, radial arterial access, adjunctive antiplatelet therapy, intravascular imaging, and optimized pharmacological management, have significantly enhanced procedural success rates and patient survival following PPCI.⁽¹⁰⁾ Nevertheless, adverse in-hospital outcomes such as heart failure, arrhythmias, bleeding complications, no-reflow phenomenon, and mortality remain important clinical concerns, particularly in developing countries where delays in presentation and limited healthcare resources may negatively affect outcomes.⁽¹¹⁾ Several international registries and observational studies have evaluated the outcomes of PPCI in STEMI patients and reported variable rates of successful reperfusion and in-hospital mortality depending on healthcare infrastructure and patient characteristics. Takamizawa et al. demonstrated that PPCI performed even by less experienced operators under expert supervision resulted in acceptable long-term cardiovascular outcomes.⁽¹²⁾ Likewise, Chacón-Diaz et al. reported that timely reperfusion significantly influenced clinical outcomes in STEMI patients undergoing invasive reperfusion strategies.⁽¹¹⁾ In Iraq, limited local data are available regarding the real-world outcomes of PPCI among STEMI patients. Therefore, evaluating procedural success, complications, and short-term clinical outcomes is important for assessing the quality of interventional cardiac services and identifying areas requiring improvement. Accordingly, the present study aimed to evaluate the outcomes of primary percutaneous coronary intervention in patients with acute ST-segment elevation myocardial infarction treated at Al-Kindi Teaching Hospital.

Study Design and Setting This observational prospective study was conducted at the Department of Interventional Cardiology in Al-Kindi Teaching Hospital over a period extending from 1st October 2023 to 30th March 2026. The study aimed to evaluate the clinical and procedural outcomes of primary percutaneous coronary intervention in patients presenting with acute ST-segment elevation myocardial infarction. Study Population A total of 160 patients diagnosed with acute STEMI and treated with primary percutaneous coronary intervention were enrolled in the study. All patients were admitted through the emergency department or coronary care unit and underwent urgent coronary angiography followed by PPCI according to current international guidelines. Inclusion Criteria The study included patients who fulfilled the following criteria: 1. Adult patients aged 18 years or older. 2. Diagnosis of acute ST-segment elevation myocardial infarction based on clinical presentation, electrocardiographic findings, and cardiac biomarker elevation according to the Fourth Universal Definition of Myocardial Infarction. 3. Patients presenting within 12 hours from symptom onset. 4. Patients who underwent primary percutaneous coronary intervention as the initial reperfusion strategy. Exclusion Criteria Patients were excluded from the study if they had any of the following: 1. Patients treated with thrombolytic therapy before coronary intervention. 2. Patients with non-ST-segment elevation myocardial infarction or unstable angina. 3. Patients with incomplete clinical or procedural data. 4. Patients who refused participation in the study. Data Collection Data were collected using a specially designed case sheet through direct patient interviews, clinical examination, hospital records, laboratory investigations, electrocardiography, echocardiography, and coronary angiography reports. The collected variables included: • Demographic characteristics including age and sex. • Cardiovascular risk factors including hypertension, diabetes mellitus, smoking, dyslipidemia, and family history of coronary artery disease. • Clinical presentation and symptom onset time. • Killip classification on admission. • Electrocardiographic findings and infarct location. • Laboratory investigations including cardiac troponin levels and routine biochemical parameters. • Angiographic findings including culprit vessel, number of diseased vessels, TIMI flow before and after intervention, and stent implantation. • Procedural characteristics including vascular access site and door-to-balloon time. • In-hospital outcomes and complications including arrhythmias, heart failure, cardiogenic shock, bleeding complications, reinfarction, stroke, and mortality. Outcome Measures The primary outcome measures included procedural success and in-hospital mortality. Procedural success was defined as restoration of TIMI grade III coronary flow in the infarct-related artery after PCI with residual stenosis less than 20%. Secondary outcomes included in-hospital complications such as heart failure, cardiogenic shock, arrhythmias, major bleeding, and length of hospital stay. Statistical Analysis Data were analyzed using the Statistical Package for the Social Sciences (SPSS) version 26. Continuous variables were presented as mean ± standard deviation, while categorical variables were expressed as frequencies and percentages. Comparisons between variables were performed using the Chi-square test for categorical variables and Student’s t-test for continuous variables. A p-value of less than 0.05 was considered statistically significant. Ethical Considerations The study was conducted in accordance with the principles of the Declaration of Helsinki. Ethical approval was obtained from the scientific and ethical committee of Al-Kindi Teaching Hospital prior to study initiation. Written informed consent was obtained from all participants before enrollment in the study.

The study showed that males constituted the majority of the patients undergoing primary percutaneous coronary intervention, accounting for 118 (73.8%) cases, while females represented 42 (26.2%) cases. The mean age of the study population was 59.8 ± 11.6 years. Patients aged 50–69 years represented the largest proportion of cases (61.3%). No statistically significant difference was observed between age categories and gender distribution (p=0.412).

Table 1: Demographic Characteristics of Patients with Acute STEMI Undergoing PPCI

The study showed that smoking was the most prevalent cardiovascular risk factor among STEMI patients, reported in 92 (57.5%) patients, followed by hypertension in 84 (52.5%) and diabetes mellitus in 66 (41.3%) patients. Dyslipidemia was identified in 58 (36.3%) cases. A statistically significant association was observed between smoking and male gender (p<0.001).

The study showed that anterior wall myocardial infarction represented the most common infarct location in 70 (43.8%) patients, followed by inferior wall myocardial infarction in 56 (35.0%) patients. Most patients presented with Killip class I (71.9%), while cardiogenic shock (Killip IV) was observed in 8.1% of cases. A statistically significant relationship was observed between higher Killip class and in-hospital complications (p=0.002).

Table 2: Distribution of Cardiovascular Risk Factors Among STEMI Patients

Table 3: Clinical Presentation and Killip Classification of STEMI Patients

The study showed that the left anterior descending artery was the most frequently affected culprit vessel in 72 (45.0%) patients. Radial access was used in 138 (86.3%) procedures, whereas femoral access was used in 22 (13.7%) procedures. Successful reperfusion with final TIMI III flow was achieved in 142 (88.8%) patients. The mean door-to-balloon time was 94.5 ± 28.4 minutes. TIMI III flow was significantly associated with lower mortality and fewer complications (p=0.001).

Table 4: Angiographic and Procedural Findings of PPCI

The study showed that heart failure was the most common in-hospital complication occurring in 24 (15.0%) patients, followed by arrhythmias in 20 (12.5%) patients. Cardiogenic shock developed in 13 (8.1%) patients, while in-hospital mortality occurred in 11 (6.9%) cases. Major bleeding complications were uncommon and reported in only 5 (3.1%) patients. A statistically significant association was found between prolonged door-to-balloon time and increased mortality (p=0.003).

The study showed that the mean symptom onset-to-first medical contact time was 118.6 ± 54.2 minutes, while the mean door-to-balloon time was 94.5 ± 28.4 minutes. Patients with door-to-balloon time ≤90 minutes demonstrated significantly lower rates of cardiogenic shock and mortality compared with those with prolonged reperfusion times (p=0.001).

4.7. Echocardiographic Findings Following PPCI

The study showed that preserved left ventricular systolic function (LVEF ≥50%) was observed in 63 (39.4%) patients, while moderately reduced ejection fraction (40–49%) was found in 58 (36.3%) patients. Severely reduced ejection fraction (<40%) was identified in 39 (24.3%) patients and was significantly associated with higher in-hospital complications and mortality (p=0.002).

Table 6: Time-to-Reperfusion Characteristics Among STEMI Patients Undergoing PPCI

Table 5: In-Hospital Outcomes and Complications Following PPCI

Table 7: Echocardiographic Findings Among STEMI Patients After PPCI

The study showed that patients with left anterior descending artery involvement had significantly higher rates of heart failure and reduced left ventricular ejection fraction compared with other culprit vessels (p=0.004). Mortality was also more frequent among patients with left main coronary artery disease.

Table 8: Association Between Culprit Vessel and In-Hospital Outcomes

The study showed that achievement of TIMI III flow after PPCI was associated with significantly lower rates of heart failure, cardiogenic shock, and mortality compared with TIMI I–II flow (p<0.001).

Table 9: Relationship Between Final TIMI Flow and In-Hospital Outcomes

The study showed that most patients had hospital stays ranging from 4–7 days, accounting for 96 (60.0%) patients. Prolonged hospitalization (>7 days) was significantly associated with heart failure, cardiogenic shock, and reduced ejection fraction (p=0.002).

Table 10: Length of Hospital Stay Among STEMI Patients

The study showed that diabetes mellitus, hypertension, smoking, and reduced ejection fraction were significantly associated with increased in-hospital mortality among STEMI patients undergoing PPCI (p<0.05).

Table 11: Association Between Risk Factors and In-Hospital Mortality

The study showed that radial access was associated with higher procedural success and lower bleeding complications compared with femoral access, with statistically significant differences observed regarding bleeding events (p=0.018).

Table 12: Procedural Outcomes According to Vascular Access Site

Primary percutaneous coronary intervention (PPCI) is considered the gold standard reperfusion strategy for patients presenting with ST-Elevation Myocardial Infarction because of its superior efficacy in restoring coronary blood flow, reducing infarct size, preserving ventricular function, and improving survival outcomes.⁽¹⁻³⁾ The present study evaluated demographic characteristics, cardiovascular risk factors, angiographic findings, procedural success, and in-hospital outcomes among STEMI patients treated with PPCI at Al-Kindi Teaching Hospital. The current study demonstrated that males represented the majority of STEMI patients undergoing PPCI. This finding agrees with previous international and regional studies that reported male predominance among acute myocardial infarction patients.⁽⁴⁻⁷⁾ Men are generally more exposed to cardiovascular risk factors such as smoking, occupational stress, and unhealthy lifestyle behaviors, which contribute to accelerated atherosclerosis and coronary artery disease.⁽⁸⁾ The mean age of the studied population was approximately 60 years, which is comparable to findings reported by Takamizawa et al. and Klancik et al., where most STEMI patients undergoing PPCI were between 50 and 70 years old.⁽⁶,⁹⁾ Smoking was the most prevalent cardiovascular risk factor identified in the present study. Similar findings were reported by Chacón-Diaz et al. and Saeed and Faeq, who observed high smoking prevalence among STEMI patients treated with reperfusion therapy.⁽¹⁰,¹¹⁾ Smoking promotes endothelial dysfunction, inflammatory activation, oxidative stress, and platelet aggregation, thereby contributing significantly to coronary thrombosis and plaque instability.⁽¹²⁾ Hypertension and diabetes mellitus were also highly prevalent among the studied patients. This finding agrees with several previous studies that identified hypertension and diabetes as major contributors to coronary artery disease progression and adverse cardiovascular outcomes.⁽¹³⁻¹⁵⁾ Diabetes mellitus is particularly associated with diffuse coronary artery involvement, impaired microvascular perfusion, delayed myocardial recovery, and increased mortality following PPCI.⁽¹⁶⁾ Dyslipidemia was also frequently observed in the current study, further supporting the role of lipid abnormalities in the development and progression of coronary atherosclerosis.⁽¹⁷⁾ Anterior wall myocardial infarction represented the most common infarct location in the present study. Similar observations were reported by Okşen et al. and Huang et al., who demonstrated that anterior STEMI predominated among patients undergoing PPCI.⁽¹⁸,¹⁹⁾ Anterior STEMI is commonly caused by left anterior descending artery occlusion and is associated with larger infarct size, impaired left ventricular function, and increased complication rates.⁽²⁰⁾ Most patients in the current study presented with Killip class I, indicating relatively preserved hemodynamic stability at admission. However, higher Killip classification was significantly associated with increased in-hospital complications and mortality. Similar findings were reported by Amon et al. and Fang et al., who demonstrated that Killip classification remains a strong predictor of adverse outcomes after STEMI.⁽²¹,²²⁾ The angiographic findings of the current study showed that the left anterior descending artery was the most frequently affected culprit vessel. Similar results were reported by Shaaban et al. and Nozaki et al.⁽²³,²⁴⁾ LAD occlusion frequently results in extensive myocardial ischemia because this artery supplies a large portion of the left ventricle. This explains the significantly higher rates of heart failure and reduced left ventricular ejection fraction observed among patients with LAD involvement in the present study. Radial access was used in the majority of procedures in the current study. This reflects the increasing global preference for radial artery access because of its lower bleeding risk, reduced vascular complications, shorter hospitalization duration, and improved patient comfort.⁽²⁵⁾ The present study also demonstrated significantly lower bleeding complications among patients treated through radial access compared with femoral access. Similar findings were reported by Valgimigli et al., who confirmed the superiority of radial access in reducing major bleeding events and improving procedural safety in acute coronary syndrome patients undergoing PCI.⁽²²⁾

One of the most important findings of the present study was the high procedural success rate, with TIMI III flow achieved in 88.8% of patients. Comparable reperfusion success rates have been reported in several contemporary studies evaluating PPCI outcomes.⁽²³⁻²⁵⁾ Restoration of TIMI III flow is strongly associated with improved myocardial perfusion, preservation of ventricular function, and lower mortality rates.⁽²⁶⁾ In the current study, TIMI III flow was significantly associated with lower rates of heart failure, arrhythmias, cardiogenic shock, and mortality. Similar findings were demonstrated by Ndrepepa et al., who reported that impaired postprocedural TIMI flow independently predicted poor cardiovascular outcomes following STEMI.⁽²⁵⁾ The mean door-to-balloon time observed in the present study was approximately 95 minutes, which is close to internationally recommended standards.⁽¹⁾ Patients with door-to-balloon time ≤90 minutes demonstrated significantly lower rates of cardiogenic shock and mortality than those with prolonged reperfusion times. Similar findings were reported by Denktas et al. and Boersma et al., who emphasized that rapid reperfusion significantly improves myocardial salvage and survival outcomes following STEMI.⁽²⁶,²⁷⁾ Total ischemic time remains one of the most important determinants of prognosis because delayed reperfusion leads to irreversible myocardial necrosis and impaired ventricular recovery.⁽²⁸⁾ Heart failure represented the most common in-hospital complication in the present study. Similar findings were observed in contemporary STEMI registries evaluating PPCI outcomes.⁽¹⁹,²¹⁾ Heart failure after STEMI generally reflects extensive myocardial injury, delayed reperfusion, or impaired microvascular perfusion despite successful epicardial artery reopening. Arrhythmias were also common complications in the current study and may result from ischemia-related electrical instability and reperfusion injury.⁽²⁹⁾ Cardiogenic shock remained one of the most serious complications and was strongly associated with mortality, consistent with previous reports evaluating STEMI complicated by shock.⁽²⁴⁾ The in-hospital mortality rate in the present study was comparable to mortality rates reported in recent international PPCI registries.⁽⁶,⁷⁾ Mortality was significantly associated with diabetes mellitus, hypertension, smoking, prolonged door-to-balloon time, and severely reduced left ventricular ejection fraction. Similar predictors have been identified in previous studies evaluating short-term mortality following STEMI.⁽²¹,³⁰⁾ Reduced ejection fraction is widely recognized as one of the strongest prognostic indicators because it reflects extensive myocardial damage and impaired ventricular performance.⁽³⁰⁾ Echocardiographic findings in the current study demonstrated that nearly one-quarter of patients had severe left ventricular systolic dysfunction. Anterior wall hypokinesia represented the most common regional wall motion abnormality because of the predominance of LAD involvement. Similar findings were reported by Aldujeli et al. and Madsen et al. in studies evaluating ventricular remodeling and functional outcomes after STEMI.⁽²⁹,³⁰⁾ Patients with severely reduced ejection fraction experienced significantly higher mortality and prolonged hospitalization in the present study, emphasizing the prognostic importance of early ventricular function assessment after PPCI.

Overall, the findings of the present study confirm that PPCI is an effective and safe reperfusion strategy for STEMI patients in Iraqi clinical practice, with high procedural success rates and acceptable complication and mortality outcomes. Early reperfusion, achievement of TIMI III flow, radial access utilization, and minimization of door-to-balloon time remain essential determinants of improved prognosis after STEMI.