Adenosine Stress Test, Protocol, Dose Chart, CPT Code, Contraindications, Side Effects

Content:

• What is Adenosine Stress Test?
• Protocol
• Dose Chart
• CPT Code
• Contraindications
• Side Effects

What is Adenosine Stress Test?

The adenosine stress test is a diagnostic procedure used to evaluate blood flow to the heart muscle and detect coronary artery disease (CAD). Instead of relying on physical exercise, this test uses a medication called adenosine to temporarily increase blood flow in the coronary arteries. Adenosine dilates the blood vessels, creating differences in perfusion between healthy and narrowed arteries. These differences are then captured through imaging techniques such as nuclear perfusion scans, helping physicians assess areas of reduced blood flow.

This test is particularly useful for patients who cannot perform treadmill or exercise-based stress tests due to mobility issues, advanced age, or other health conditions. The adenosine stress test is widely performed in cardiology clinics and hospitals and plays a key role in non-invasive evaluation of heart health. It provides valuable insight into coronary circulation and guides further management decisions, including lifestyle changes, medications, or interventional procedures like angioplasty.

Protocol

The protocol for an adenosine stress test follows a systematic approach to ensure both safety and accuracy. Patients are usually asked to avoid caffeine and certain medications for at least 12–24 hours before the procedure, since these substances can interfere with adenosine’s action. During the test, an intravenous (IV) line is inserted, and adenosine is infused over a period of approximately 4–6 minutes. Imaging agents, such as technetium or thallium, may be administered during infusion to track blood flow in the heart.

Throughout the test, the patient’s heart rate, blood pressure, and ECG are closely monitored to detect any changes or complications. Once the infusion is complete, images are captured to compare perfusion at rest versus under stress conditions. The entire procedure typically takes between 30–60 minutes. Afterward, patients are observed briefly to ensure they are stable before discharge. The structured protocol ensures accurate results while minimizing risks.

Dose Chart

Adenosine is administered intravenously based on a standardized dose regimen. The typical dose is 140 micrograms per kilogram per minute (µg/kg/min) given as a continuous IV infusion over 4–6 minutes. This dosage achieves maximum coronary vasodilation without causing prolonged side effects. For example, a patient weighing 70 kg would receive approximately 9.8 mg per minute of adenosine during the infusion.

In some cases, adjustments may be made depending on patient tolerance, weight, and clinical response. The drug is prepared in a concentration that allows precise dosing, and infusion pumps are commonly used for accuracy. Unlike exercise stress tests, the effect is immediate and controllable—once the infusion stops, the drug’s action dissipates within seconds due to its short half-life. This makes adenosine an effective and safe pharmacologic agent for stress testing.

CPT Code

In medical billing and coding, the adenosine stress test is identified by specific CPT (Current Procedural Terminology) codes. The primary code used is **78452** when performed with nuclear myocardial perfusion imaging. This code represents the complete procedure, including stress and rest imaging studies. If only the infusion component is billed separately, CPT code **93015** may also be used for cardiovascular stress testing services.

Accurate coding is important for proper reimbursement, insurance claims, and clinical documentation. Healthcare providers ensure that the correct code is applied based on whether imaging was included and whether additional professional interpretation was required. Following CPT guidelines helps standardize reporting and ensures patients and providers are properly covered for the test.

Contraindications

While the adenosine stress test is generally safe, there are important contraindications to consider. Patients with severe asthma or chronic obstructive pulmonary disease (COPD) are at higher risk of bronchospasm, since adenosine can cause airway constriction. Likewise, individuals with second- or third-degree atrioventricular (AV) block without a pacemaker should avoid the test, as adenosine can slow heart conduction further. Severe hypotension and unstable angina are also absolute contraindications.

Relative contraindications include recent caffeine intake, uncontrolled arrhythmias, and certain medications that interact with adenosine. In such cases, physicians may opt for alternative stress agents such as regadenoson or dobutamine. Thorough patient screening before the test ensures safety and minimizes the likelihood of adverse reactions during the procedure.

Side Effects

Common side effects of the adenosine stress test are generally mild and short-lived due to the drug’s brief half-life. Patients may experience flushing, chest discomfort, shortness of breath, dizziness, or nausea during infusion. These effects typically resolve within seconds to minutes after the infusion stops. Because the drug is rapidly metabolized, no long-term side effects are expected in most patients.

However, more serious side effects can occasionally occur, such as bronchospasm, significant hypotension, or arrhythmias. These are rare but require immediate medical attention. Continuous monitoring throughout the test ensures that any complications are quickly identified and managed. Overall, the adenosine stress test is considered a safe diagnostic tool, with benefits far outweighing the risks in properly selected patients.