FREQUENCY OF FRAGMENTED QRS COMPLEX IN PATIENTS WITH ST-ELEVATED MYOCARDIAL INFARCTION UNDERGOING MYOCARDIAL REPERFUSION THERAPY IN REHMAN MEDICAL INSTITUTE, PESHAWAR: A DESCRIPTIVE CROSS-SECTIONAL STUDY

Background: Fragmented QRS (fQRS) on a standard 12-lead ECG has emerged as a clinically relevant marker of myocardial scarring and conduction disturbances in patients with ST-elevation myocardial infarction (STEMI). Despite advancements in reperfusion strategies such as percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), and thrombolysis, early identification of high-risk patients remains a priority. Understanding the frequency and distribution of fQRS in local populations can help optimize risk stratification, therapeutic decisions, and long-term management outcomes. Objective: The study aimed to determine the frequency and distribution of fragmented QRS complex patterns on 12-lead ECG in patients with STEMI undergoing different reperfusion therapies. Methods: A descriptive cross-sectional study was conducted at Rehman Medical Institute, Peshawar, from January to June 2025. A total of 276 patients diagnosed with STEMI (192 males and 84 females) who underwent reperfusion therapy were enrolled. Patients received PCI (n=140), CABG (n=79), or thrombolytic therapy (n=57). Fragmented QRS was defined as the presence of notching of the R or S wave or an additional R’ wave in at least two contiguous leads. Clinical variables including age, gender, ejection fraction (30–60%), hypertension, hyperlipidemia, smoking, obesity, and family history of myocardial infarction were recorded. Data were analyzed using SPSS version 26. Results: Fragmented QRS was observed in 161 patients (58.3%). Gender-wise distribution showed 113 males (70.2%) and 48 females (29.8%) with fQRS. Prevalence was highest in thrombolysis-treated patients (83.3% in males and 77.8% in females), followed by CABG (69.7% in males and 69.2% in females). The lowest frequency occurred in PCI-treated patients (43.8% in males and 40.9% in females). Pattern analysis revealed that the R’ wave was predominant in males (58%), while R wave notching was more frequent in females (42%). Reduced ejection fraction was more common among patients with fQRS, particularly in males. Conclusion: The study demonstrated a high prevalence of fragmented QRS among STEMI patients undergoing reperfusion therapy, particularly in those with reduced ventricular function and multiple comorbidities. Routine recognition of fQRS on ECG may serve as a cost-effective, non-invasive prognostic marker to guide clinical decision-making and improve risk stratification in acute cardiac care.