FFREIIA METHOD: A SYSTEMATIZED APPROACH TO INTERPRETING THE 12-LEAD ELECTROCARDIOGRAM FOR THE NON-SPECIALIST

Abstract

Even in the age of Artificial Intelligence, electrocardiogram (ECG) interpretation remains a challenge for many healthcare professionals outside the cardiology specialty. Therefore, the authors propose the FFREIIA-A method, a systematized and didactic tool designed to guide the analysis of 12-lead ECGs by students and non-specialist professionals. The approach seeks to balance simplicity with technical rigor, promoting greater diagnostic certainty and progressive learning. The method organizes electrocardiographic interpretation into seven sequential steps: Shape, Heart Rate, Rhythm, Cardiac Axis, Intervals, Ischemia/Infarction, and Alterations, followed by a final integrated analysis. Each step was conceived based on updated guidelines from the Brazilian Society of Cardiology and international reference literature, favoring a clinical application consistent with the reality of healthcare services. The Shape stage encompasses the analysis of the technical quality of the tracing (recording speed, calibration, applied filters), as well as the morphology of the P, QRS, T, and U waves. Next, the heart rate is calculated practically, using different methods for regular and irregular rhythms. In the Rhythm analysis, the focus is on recognizing the presence of sinus or non-sinus rhythm, emphasizing the morphology of the P wave in specific leads. The cardiac axis is evaluated based on the combined analysis of D1 and aVF, quickly identifying deviations. The Intervals stage includes PR, QRS, and QTc, highlighting their clinical implications in conduction disorders and arrhythmic risk. The investigation of Ischemia and Infarction follows objective criteria, such as ST segment changes, the presence of pathological Q waves, and T wave inversion in contiguous leads. Finally, the Alterations stage promotes a systematic review of the findings based on the FFREIIA-A model, allowing for the correlation of electrocardiographic data with the patient's clinical information. This sequential systematization allows professionals in training to conduct ECG interpretation with greater autonomy and confidence. One of the main differentiators of the FFREIIA-A method is its cyclical and revisable nature: in the face of any anomalous finding—whether technical (such as calibration errors or electrode placement), heart rate alterations (bradycardia or tachycardia), pathological intervals (such as QTc prolongation or atrioventricular blocks), signs of ischemia or infarction, or other electrolyte and metabolic alterations (such as hypo/hyperkalemia)—the interpreter is instructed to return to the previous steps of the method, systematically reassessing each component. This iterative process leads to a more robust, logical, and contextualized final diagnostic analysis, integrating the electrocardiographic findings with the patient's clinical presentation. Conclusion: The approach to electrocardiographic findings of undetermined clinical significance remains insufficiently systematized, particularly in scenarios where the initial diagnostic evaluation does not identify evidence of structural or functional cardiac pathology. This article proposes a methodological framework, based on published evidence and expert consensus, for the analysis and classification of these findings. The objective is to support the standardization of clinical decision-making, with emphasis on defining criteria for the indication of complementary diagnostic methods, determining the appropriate extent of cardiac investigation, and assessing the need for longitudinal follow-up. The FFREIIA-A method represents a valuable teaching and clinical practice tool for ECG interpretation by non-specialists. Its systematized application can reduce errors, increase the autonomy of professionals in training, and support real-time clinical decisions. Its inclusion in medical education programs and multidisciplinary health training is recommended.