93024

Ergonovine Provocation Test

CPT 93024 describes the ergonovine provocation test, a specialized diagnostic procedure utilized primarily in the cardiac catheterization laboratory to induce coronary artery vasospasm in patients suspected of having Prinzmetal's (variant) angina. This condition is characterized by chest pain at rest associated with transient ST-segment elevation on the electrocardiogram, often occurring in individuals with otherwise normal or non-obstructive coronary arteries. During the procedure, the patient is carefully monitored via continuous 12-lead ECG and invasive blood pressure measurement. Ergonovine maleate, a potent vasoconstrictor that acts on alpha-adrenergic and serotonergic receptors in the vascular smooth muscle, is administered intravenously or intracoronary in incremental, escalating doses. The clinician performs coronary angiography at baseline and after each dose of ergonovine to visualize luminal narrowing. A positive test is generally defined as the induction of focal or diffuse coronary artery spasm causing significant luminal narrowing (typically greater than 70 to 90 percent) accompanied by the patient's typical chest pain and/or ischemic ECG changes. Because the test carries risks of severe ischemia, myocardial infarction, or life-threatening arrhythmias, it must be performed in a highly controlled environment by experienced cardiologists. Once a spasm is induced or the maximum dose is reached, intracoronary nitroglycerin is promptly administered to reverse the vasoconstriction and restore normal blood flow. This test is crucial for patients whose symptoms suggest ischemia despite relatively clean angiograms, allowing for the initiation of appropriate therapy such as calcium channel blockers or long-acting nitrates.

Clinical Indications

  • Suspected Prinzmetal's or variant angina
  • Recurrent chest pain at rest with normal or near-normal coronary arteries
  • Syncope of unknown origin with suspected cardiac etiology
  • Exertional chest pain not explained by obstructive coronary disease
  • Sudden cardiac arrest survivors where vasospasm is a suspected trigger

Procedure Steps

  1. Establish baseline cardiac hemodynamics and perform initial coronary angiography.
  2. Ensure continuous 12-lead ECG and invasive arterial pressure monitoring.
  3. Administer ergonovine maleate in incremental doses (e.g., 0.05 mg, 0.1 mg, 0.2 mg) intravenously or intracoronary.
  4. Wait for a specified interval between doses to monitor for symptoms or ECG changes.
  5. Repeat coronary angiography after each dose or at the onset of symptoms/ECG changes.
  6. Assess for luminal narrowing, ST-segment elevation/depression, and symptom reproduction.
  7. Administer intracoronary nitroglycerin immediately upon confirmation of spasm or completion of the protocol to reverse vasoconstriction.
  8. Perform final angiographic assessment to ensure the coronary arteries have returned to baseline diameters.
  9. Monitor the patient post-procedure for any delayed reactions or arrhythmias.

Coding Guidelines

  • Code 93024 covers the ergonovine provocation test itself, including monitoring and interpretation.
  • This procedure is typically performed in conjunction with cardiac catheterization; refer to codes 93451-93461 for the primary catheterization services.
  • Do not report 93024 as a standalone code if it is considered part of a larger bundled experimental protocol unless clinical documentation supports separate necessity.
  • Supplies used during the test, such as the ergonovine maleate medication, may sometimes be reported separately depending on the payer and the setting (e.g., HCPCS J-codes).
  • Ensure that the medical record clearly documents the dosages of ergonovine and the specific physiological responses observed.

Associated ICD-10 Codes