From the Guidelines
NSTEMI does not necessarily present with chest pain, as some patients may experience atypical or silent presentations, particularly in elderly patients, women, and those with diabetes or chronic kidney disease. According to the 2021 European Society of Cardiology guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation 1, the clinical presentation of acute coronary syndromes is broad and may include symptoms other than chest pain. Some patients may present with dyspnea, epigastric pain, or pain in the left arm, while others may have no symptoms at all, with the NSTEMI only being detected through abnormal cardiac biomarkers and ECG changes during routine testing.
The 2011 ACCF/AHA focused update incorporated into the ACC/AHA 2007 guidelines for the management of patients with unstable angina/non-ST-elevation myocardial infarction 1 also highlights the variability in presentation of NSTEMI, noting that some patients may have no chest discomfort but present solely with jaw, neck, ear, arm, shoulder, back, or epigastric discomfort or with unexplained dyspnea without discomfort. The guidelines emphasize the importance of considering NSTEMI in high-risk patients even without typical chest pain, as the underlying pathophysiology remains the same regardless of symptoms: partial blockage of a coronary artery leading to damage of heart muscle tissue.
Key points to consider in the diagnosis of NSTEMI include:
- Atypical presentations are more common in elderly patients, women, and those with diabetes or chronic kidney disease
- Symptoms may include shortness of breath, fatigue, nausea, vomiting, sweating, lightheadedness, or pain in other locations such as the jaw, neck, back, or arms
- Some patients may have no symptoms at all, with the NSTEMI only being detected through abnormal cardiac biomarkers and ECG changes during routine testing
- The underlying pathophysiology remains the same regardless of symptoms: partial blockage of a coronary artery leading to damage of heart muscle tissue.
From the Research
Presentation of Non-ST-Elevation Myocardial Infarction (NSTEMI)
- NSTEMI does not necessarily present with chest pain, as some patients may experience atypical symptoms or no chest pain at all 2, 3, 4.
- Studies have shown that a significant proportion of patients with NSTEMI present without chest pain, with estimates ranging from 6.4% to 43.6% 2, 4.
- Patients with NSTEMI who present without chest pain are often older, more frequently female, and have a higher prevalence of comorbidities such as diabetes and heart failure 2, 4.
Diagnostic Challenges
- The absence of chest pain can lead to delayed diagnosis and treatment of NSTEMI, as patients may not be recognized as having acute coronary syndrome (ACS) 3, 4.
- Electrocardiograms (ECGs) may be normal or non-diagnostic in patients with NSTEMI, making diagnosis more challenging 5, 6.
- Cardiac enzyme levels, such as troponin I, are essential for diagnosing NSTEMI, even in patients with normal ECGs 6.
Treatment and Outcomes
- Patients with NSTEMI who present without chest pain are less likely to receive evidence-based medical therapies and invasive cardiac procedures, which can lead to poorer outcomes 2, 3.
- Hospital mortality is higher in patients with NSTEMI who present without chest pain, compared to those with typical symptoms 2, 3, 4.
- Atypical symptoms are an independent predictor of 1-year mortality in patients with NSTEMI 3.