Coronary Artery Disease (CAD) is among the leading causes of mortality in the U.S. CAD affects some 16 million people in the U.S., causes 1.2 million heart attacks, and over 450,000 deaths, according to the American Heart Association. The direct costs of CAD are estimated at over $87 billion. Because current diagnostic techniques are often equivocal, nearly two million, primarily low to mid risk patients are admitted from emergency departments (ED) to the hospital for further testing at an annual cost of $10-$13 billion; CAD is subsequently ruled out in these patients.
Coronary CT Angiography (cCTA) has demonstrated particular promise in single and multicenter trials as a powerful tool to rule out patients suspected of CAD who are at low to mid risk. In these studies, cCTA has demonstrated negative predictive values approaching 100 percent (i.e. every patient ruled out by cCTA was also ruled out based on a ‘gold standard,’ such as coronary angiography). In addition, studies have demonstrated that cCTA is cost effective in the ED setting because it can both shorten patient time in the ED and provide a more accurate assessment of heart attack risk, reducing both inappropriate patient admissions and discharges.
Despite cCTA’s demonstrated potential as an effective diagnostic modality there are several challenges associated with its use which have slowed adoption and led to underutilization. Analysis of cCTA studies is complex, and thus requires special expertise to interpret the results. This requirement, along with time needed to analyze cCTA studies, often creates turnaround time bottlenecks that hinder the timeliness of delivering appropriate patient care. In the ED setting for example, where timely decision making is critical to patient care and avoiding unnecessary admissions, expert radiologist or cardiologist readers are not usually available 24/7.