Acute onset chest pain is a common presentation at the emergency department. It encompasses some life-threatening diagnoses and accounts for a considerable portion of admissions. The most common important diagnosis that should be confirmed or excluded is acute coronary syndrome.1
Chest pain units are designed to rule in or rule out acute myocardial ischemia by several protocols and non-invasive modalities.1
Their use involves the assessment of the likelihood of acute coronary syndrome (and not non-cardiac chest pain) and risk stratification of patients with acute coronary syndrome.3
Hence, a chest pain unit is based on an accelerated diagnostic strategy containing clinical observation, serial ECGs, and cardiac markers.1
Assessment of patients with high probability of ischemic heart disease requires a protocol to test cardiac necrosis and ischemia during rest and stress conditions.4
Therefore, chest pain units do not decrease admission rates for patients who have acute coronary syndrome. They in fact decrease unnecessary hospitalization.5
Unnecessary admissions of patients can lead to crowding of wards and suboptimal patient care and resource use.1
This benefit is not limited to patients presenting with chest pain but can be applied to patients presenting with exacerbation of heart failure.1
Our results showed that 43% of patients had been discharged after evaluation in chest pain unit during 2010. However, this rate was only 26% using traditional methods during 2007. On the other hand, CCU admission rate was also increased from 23% to 36% using chest pain units. The main explanation may be the decreased number of patients that had discharged themselves against medical advice (37% using traditional methods vs. 14% using chest pain units). It means the emergency ward care has been improved and more patients were satisfied.
The mortality rate increased from 1.1% in 2007 to 1.3% in 2010. However, the difference was not statistically significant. It may be related to the decreased number of patients who had left the emergency ward against medical advice and increased number of patients who underwent invasive procedures during their hospital stay. Consequently, in our conditions, it is useful to provide a chest pain unit in emergency wards of general hospitals to reduce unnecessary admissions and improve patients and their families’ satisfaction. Each chest pain unit should have a protocol according to the equipments they can access. Although we performed this task with the least facilities, an ideal chest pain unit should be better equipped. In many cardiovascular emergency centers, radionuclide perfusion imaging and multislice computed tomography scan are used as important tools to assess patients who present with possible acute coronary syndrome.4
Ideally, cardiac biomarkers bedside testing gives the physician rapid data such as CK-MB and the troponins I and T levels. It thus allows the physicians to quickly stratify risks in chest pain units.4
Measuring myoglobin combined with more specific cardiac biomarkers in a serial fashion is also recommended. The negative predictive value of normal myoglobin levels during six hours of observation and without doubling over any two-hour period is 97%. It is most valuable in patients presenting early in the course of symptoms.4
Because the patients are in the chest pain unit for at least six hours, providing some comforts that are not generally available in traditional emergency wards (like meals, hospital beds, and television sets) can improve patient satisfaction.4
A chest pain unit also requires trained nurses because the patients require close monitoring and assessment, serial biomarker testing, ECG, and noninvasive testing.4
Our study had some important limitations. First, we did not follow the patients after discharge. Therefore, we cannot estimate the percentage of patients with undiagnosed acute coronary syndrome who had been discharged. Moreover, we cannot estimate the real mortality rate. Second, we did not evaluate the cost-effectiveness of chest pain unit. A comprehensive study to assess the cost-effectiveness of chest pain units can thus be very helpful.
Providing a special chest pain unit in emergency departments of general hospitals or adjacent to it is useful. It reduces unnecessary admission of patients without coronary artery disease and improves patient satisfaction.