Acute coronary syndrome(ACS) classically manifests with chest pain; however, up to one-third of patients present with atypical symptoms such as isolated back pain, nausea, fatigue, or diaphoresis. These presentations pose a significant diagnostic challenge in primary care, where rapid identification and referral are critical to prevent morbidity and mortality. This case illustrates how clinical vigilance, combined with the use of a national digital risk-stratification tool, enabled timely recognition of ACS despite the absence of chest pain.A48-year-old man with  family health center with six hours of persistent upper back pain, nausea, and mild diaphoresis, but without chest discomfort.. Physical examination was unremarkable, and musculoskeletal palpation did not reproduce symptoms. Although the presentation appeared non-cardiac at first glance, the family physician evaluated cardiovascular risk using Türkiye’s national digital decision-support system. Based on the patient’s age, smoking status, dyslipidemia, and symptoms,HYP indicated a moderate-to-high 10-year cardiovascular risk and recommended ECG despite the atypical presentation. An in-clinic ECG showed non-specific ST-T abnormalities. Hospital evaluation demonstrated elevated troponin I levels, confirming NSTEMI.This case emphasizes that ACS may present without chest pain and that digital decision-support platforms can play a pivotal role in guiding diagnostic decisions in real time. The integration of HYP into routine assessment prevented potential diagnostic delay by alerting the clinician to cardiovascular risk despite nonclassical symptoms.Atypical symptoms alone should not rule out ACS, especially in individuals with cardiovascular risk factors. Combining clinical judgment with validated digital tools enhances risk stratification and supports timely referral. Wider integration of decision-support systems into primary care may reduce missed ACS diagnoses and improve outcomes.Literature indicates that atypical ACS presentations are associated with delayed care and worse prognosis. This case demonstrates that primary care clinicians must consider ACS in patients with unexplained upper back pain and risk factors.Digital platforms may augment clinical vigilance by triggering cardiac evaluation before overt myocardial injury occurs.ACS can present atypically, and reliance on classical chest pain may lead to missed or delayed diagnosis. Continuous symptom vigilance, awareness of risk factors, and technology-assisted clinical decision-making can support accurate evaluation and prompt referral, strengthening primary care management of ACS.