ABSTRAK Latar Belakang: Gagal Jantung dibagi menjadi 3 kelompok yaitu gagal jantung fraksi ejeksi menurun (HfrEF <40%), rentang tengah (HFmrEF 40-49%), dan terpelihara (HfpEF ≥50%). Ekokardiografi masih menjadi pemeriksaan standar saat ini, sayangnya pemeriksaan tersebut masih terbatas dibeberapa pusat kesehatan. Perlu pemeriksaan awal yang lebih sederhana salah satunya elektrokardiografi (EKG) yang mudah digunakan. Penentuan skoring dari EKG diharapkan dapat memudahkan memprediksi fraksi ejeksi dan memberikan terapi yang tepat. Metode Penelitian: Pendekatan observasional dengan desain potong lintang. Diambil data rekam medis pasien gagal jantung kronik (GJK) di poliklinik Jantung RSUP Dr. M.Djamil Padang bulan Januari-Agustus 2017. Dilakukan analisis bivariat pada varibel EKG terhadap fraksi ejeksi dengan metode chi-square. Analisis multivariate dengan uji regresi binari logistik untuk mendapatkan variabel pada kalkulasi skor dengan uji Hosmer-Lameshow (p<0,25). Skoring dilakukan uji sensitivitas, spesifisitas dan analisis receiver operating curve (ROC). Hasil Penelitian : 283 subjek GJK dibagi menjadi tiga kelompok. Variabel yang memenuhi persyaratan untuk dilakukan kalkulasi skor adalah pembesaran atrium kiri (LAE) (OR=6,36; p= 0.000) dengan skor 2, QRS lebar (OR=13,06; p= 0.000) dengan skor 3, interval QTc memanjang (OR=2,18; p= 0.065) dengan skor 1 dan perubahan gelombang ST-T (OR=5,05; p= 0.000) dengan skor 2. Subjek dengan HFpEF mempunyai skor <3, HFmrEF mempunyai skor 3-4, dan HFrEF mempunyai skor >4. Sistem skoring EKG memiliki sensitivitas 71,4% dan spesifisitas 88,6% dengan AUC 87,9% Kesimpulan : Sistem skoring EKG pada penelitian ini dapat digunakan sebagai pedoman awal dalam menentukan fraksi ejeksi ventrikel kiri pada pasien GJK Kata kunci : elektrokardiografi, gagal jantung kronik, fraksi ejeksi ventrikel kiri Background: Heart failure (HF) are divided into HF reduced ejection fraction (HFrEF<40%), mid range (HFmrEF 40-49%), and preserved (HFpEF ≥50%). Nowadays echocardiography is used as gold standard examination, but it is limited only in several health centers. For this reason, a preliminary examination tools is needed. Electrocardiographic (ECG) examinations tool that available almost at every health center and easy to be used. Calculating the scores from ECG variables to determine the EF will make clinician’s earlier to give initial terapi Method: An observational approach with cross sectional study design. The data was taken from patient’s medical record with chronic heart failure (CHF) who went to the Tepartement of Cardiology at Dr. M. Djamil Padang Hospital in January-August 2017. Bivariate analysis was performed on each ECG variable then correlated with LVEF by chi-square method. Multivariate analysis with logistic binary regression test was conducted to obtain variables that would go into the score calculation stage with the Hosmer-Lameshow test (p <0.25). The sensitivity, specificity test and receiver operating curve (ROC) analysis were performed. Result: 283 subjects of CHF who had been divided into three groups. Obtained variables that met the requirements for calculating scores were left atrial enlargement (LAE) (OR = 6.36; p = 0.000) score was 2, wide QRS (OR = 13.06; p = 0,000) score was 3 , prolonged QTc interval (OR = 2,18; p = 0,065) score was 1 and ST-T change (OR = 5.05; p = 0.000) score was 2. Subjects with HFpEF if the scored were <3, HFmrEF if the scored were 3-4, and HFrEF if the scored were >4. It has sensitivity 71,4%, specificity 88,6% with AUC 87,9%. Conclusion: Electrocardiography scoring system in this study can be used as an initial tools to determining LVEF in patients with CHF. Keywords: electrocardiography, chronic heart failure, left ventricular ejection fraction