Seattle Angina Questionnaire and Quality of Life in Chronic Coronary Syndrome: Opportunities for Implementation in Bulgarian Clinical Practice – A Narrative Review

Background: Chronic coronary syndrome (CCS) is a leading cause of morbidity and mortality worldwide, substantially impairing patients’ quality of life. Patient-reported outcomes (PROs) complement traditional clinical endpoints, with the Seattle Angina Questionnaire (SAQ) recognized as the most validated disease-specific tool for assessing symptom burden and health-related quality of life. Methods: A narrative review of the literature was conducted through searches in PubMed, Scopus, and Web of Science, focusing on studies evaluating the SAQ’s development, validation, clinical applications, and prognostic value, as well as its potential use in Bulgaria. Results: Evidence from pivotal trials consistently demonstrated the sensitivity of the SAQ in detecting treatment-related benefits. In the COURAGE trial, percutaneous coronary intervention (PCI) in addition to optimal medical therapy improved angina frequency and quality of life without affecting mortality. The ISCHEMIA trial confirmed greater improvements in SAQ scores with an initial invasive strategy, particularly in patients with frequent baseline angina. The EuroCTO trial showed significant gains in angina relief and quality of life following successful revascularization of chronic total occlusions. Observational registries further established low baseline SAQ scores as predictors of hospitalization and mortality. Conclusions: The SAQ is an indispensable instrument for quantifying quality of life in patients with CCS. Its systematic implementation in Bulgaria would align national practice with international standards, enhance patient-centered decision-making, and strengthen research capacity. Keywords