The Limitations of Current CAD Tests

Cardiovascular diseases (CVDs) remain the leading cause of death globally, with recent estimates showing a continued rise in the total number of fatalities. In 2023, nearly 20 million people died from CVDs. Ischemic heart disease (also known as coronary artery disease or CAD) is the world’s biggest killer, accounting for roughly 9 million deaths annually¹˒². Each day, many people experience chest pain, shortness of breath, dizziness or nausea. People often see these as signs of CAD. However these symptoms of heart problems are not always indicative for CAD. In fact, most people with CAD have no signs until the condition is more serious. This makes accurate and timely diagnosis extremely challenging³.

Heartbeat over a globe illustration

Why CAD Often Goes Undetected

Coronary artery disease (CAD) usually involves blockages in the main coronary arteries. This leads to myocardial ischemia. Myocardial ischemia happens when the heart’s need for oxygen does not match its supply.

This ischaemia-centric model, despite being present for centuries, has shown limitations in clinical practice. By the time ischaemia is detectable, the disease is often already advanced, limiting opportunities for preventive care and making treatment more invasive and costly.

coronary artery disease leads to Myocardial ischemia graphic
A range of diagnostic methods is available, including ECG stress tests, echocardiography, CT angiography and invasive coronary angiography. However, each faces limitations in accessibility, diagnostic accuracy and scalability¹⁰˒¹¹˒¹². Most are resource-intensive, require specialist interpretation, or are poorly positioned to detect asymptomatic CAD. Stress tests can sometimes produce false-negative or inconclusive results, particularly in women and people with microvascular disease¹³˒¹⁴. This can cause healthcare providers to refer patients too late or refer individuals who do not actually have CAD, leading to delayed care for those at true risk and unnecessary testing for others. This adds pressure to cardiology services and increases healthcare costs.
Patient undergoing CT angiography procedure

A Risk Assessment System Designed for Symptomatic Patients

Doctors calculate pre-test probability (PTP) using a person’s age, sex, and symptoms like chest pain or shortness of breath.

According to the American College of Cardiology (ACC) and the American Heart Association (AHA) guidelines, healthcare professionals should further diagnose the risk for coronary artery disease (CAD) when a person’s pre-test probability is above 15%. If PTP is between 5% and 15%, doctors may decide based on each case.

The European Society of Cardiology (ESC) recommends no testing for coronary artery disease (CAD) when a person’s pre-test probability is 5% or lower. If the PTP falls between 5% and 15%, doctors should decide on testing based on the individual case².

Patients with angina and/or dyspnoea and suspected coronary artery disease

Pre-test probability of coronary artery disease

Typical
Atypical
Non-anginal
Dyspnoea
Age
Men
Women
Men
Women
Men
Women
Men
Women
30-39
3%
5%
4%
3%
1%
1%
0%
3%
40-49
22%
10%
10%
6%
3%
2%
12%
3%
50-59
32%
13%
17%
6%
11%
3%
20%
9%
60-69
44%
16%
26%
11%
22%
6%
27%
14%
70+
52%
27%
34%
19%
24%
10%
32%
12%

Click to enlarge table

In practice, most screening for coronary artery disease (CAD) still centers on common symptoms, rather than a person’s actual risk factors such as underlying physiology or family history, even though all three contribute significantly to coronary risk³.

As a result, individuals who do not present symptoms but may have underlying coronary conditions are often classified as low risk. These individuals typically aren’t screened for CAD and are rarely referred for further risk assessment. This symptom-based approach means silent CAD frequently goes undetected, excluding many at-risk individuals from existing screening protocols.

Patient undergoing CardioClin test - Doctor viewing test progress in application HeartForce

The Inefficacy of Symptom-Based CAD Risk Screening

Even in patients with symptoms, available risk screening tests are less than ideal. Studies show that 4 out of 5 patients sent for testing don’t have obstructive coronary artery disease (CAD). Most tests come back negative, yet many patients still go through extra procedures and face higher costs, even though they’re not truly at risk⁴.

This over-referral leads to:

  • Improper usage of limited healthcare resources
  • Unnecessary patient anxiety
  • High system costs
  • Delays in identifying those truly at risk


Not only is CAD underdiagnosed, it is overexamined in the wrong populations.

Doctor examining patient's heart rhythm

Diagnostic Gaps Across Care Settings

The issue is not limited to general practice. Across hospitals and clinics, healthcare professionals decide who gets tested for coronary artery disease (CAD) based on a person’s symptoms. But these symptoms don’t always match the real disease, so many cases go missed or misjudged. 

As a result:

  • Emergency departments often overuse high-cost imaging
  • General practitioners often refer patients to rule out CAD when faced with diagnostic uncertainty
  • Specialists face overloaded workflows when evaluating false positives


Current screening technology is reactive, designed to confirm disease after symptoms appear. But the opportunity is truly in identifying CAD risk sooner, especially in high risk patients with multiple CAD-associated risk factors. Not only will it improve clinical outcomes, but it will also significantly reduce the healthcare burden.

Medical professional analyzing heart images.

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