Common Heart Test May Miss Deadly Disease, Study Warns
A new study from King’s College London has raised serious concerns about the reliability of one of the most widely used tests for diagnosing heart disease, revealing that it may miss the deadliest form in more than 25 percent of patients.
The research, published in Heart, focused on patients with inwardly damaged coronary arteries, a condition known as Ischemia with No Obstructive Coronary Arteries (INOCA). This lesser-known but highly dangerous form of heart disease doesn’t block arteries in the traditional way, and as a result, often escapes detection using standard stress tests and angiograms.
“This is a blind spot in modern cardiology,” said Professor Geraldine Ong, lead author of the study. “Our findings show that people are being sent home with a clean bill of health, and then suffering heart attacks or worse, because the problem was never caught.”
The study examined data from thousands of patients who had undergone conventional cardiac tests but continued to report chest pain, shortness of breath, and fatigue. Upon more advanced testing, a significant proportion were found to have microvascular dysfunction, a condition where tiny blood vessels in the heart malfunction, restricting blood flow without visible blockages.
Patients with INOCA are twice as likely to experience heart attacks or heart failure over a ten-year period compared to healthy individuals, yet they are rarely diagnosed or treated properly.
The King’s team calls for immediate changes in clinical guidelines, urging doctors to consider alternative diagnostic tools, such as coronary function testing, especially in women, who are disproportionately affected.
“This is not just a technical issue, it's a public health failure,” said Ong. “We need to update how we detect heart disease, or we risk losing patients who might otherwise survive.”
The takeaway? Normal test results don’t always mean a healthy heart. For many, the most dangerous disease is the one that hides in plain sight.