Cardiology Coding Alert

When the electrophysiologist stops an ablation mid-procedure, look to these modifiers.

Catheter ablation procedures are common in electrophysiology (EP) labs, but not every attempted ablation is completed. Sometimes the physician begins a planned ablation and determines the patient needs a different intervention instead — such as an atrioventricular (AV) nodal ablation combined with a dual-chamber pacemaker (PPM) upgrade. When this occurs, you have to determine how to report the attempted service accurately and compliantly.

Understanding when a procedure qualifies as discontinued — and how to support the claim with documentation — can help reduce denials and ensure proper reimbursement.

Below are key coding tips for reporting an ablation attempt that is stopped before completion.

First, Understand What an Ablation Procedure Entails

Electrophysiologists perform catheter ablation to treat abnormal heart rhythms by destroying small areas of heart tissue responsible for abnormal electrical signals. They guide catheters through the vascular system into the heart and deliver energy — typically radiofrequency or cryothermal energy — to eliminate the arrhythmogenic tissue.

Common ablation procedures in the CPT^® code book include:

• 93650 (Intracardiac catheter ablation of atrioventricular node function, atrioventricular conduction for creation of complete heart block, with or without temporary pacemaker placement)
• 93653 (Comprehensive EP evaluation; with treatment of supraventricular tachycardia by ablation of fast or slow atrioventricular pathway, accessory atrioventricular connection, cavo-tricuspid isthmus or other single atrial focus or source of atrial re-entry)
• 93654 (Comprehensive EP evaluation; with treatment of ventricular tachycardia or focus of ventricular ectopy including left ventricular pacing and recording, when performed)
• 93656 (Comprehensive EP evaluation; with atrial fibrillation by pulmonary vein isolation, including intracardiac electrophysiologic 3-dimensional mapping, intracardiac echocardiography with imaging supervision and interpretation, right ventricular pacing/recording, and His bundle recording, when performed)
• During an EP procedure, physicians may begin mapping or preparing for ablation but stop the procedure after identifying new clinical findings. For example, mapping may reveal that the patient requires AV nodal ablation with permanent pacing rather than the originally planned ablation approach.

When this happens, you have to determine whether the attempted ablation qualifies as a discontinued procedure.

Tip 1: Determine Whether the Procedure Was Truly Discontinued

Before assigning modifiers, verify whether the procedure meets the definition of a discontinued procedure.

A discontinued procedure typically occurs when the physician starts the procedure and it is terminated before completion due to patient safety concerns, clinical findings, or other extenuating circumstances.

If the electrophysiologist begins the EP study or delivers ablation energy but must stop the procedure due to changing clinical conditions, safety concerns, or other extenuating circumstances, the case may qualify as a discontinued procedure. Clear documentation must support why the procedure was terminated and what portion of the planned service was performed.

If the physician never began the procedure (for example, the patient became unstable before the procedure started), the discontinued procedure modifiers should not be used. Instead, code only what was actually performed, if anything.

Tip 2: Use the Correct Modifier for a Discontinued Procedure

The most common modifier used by physicians to report a discontinued procedure is modifier 53 (Discontinued Procedure). This modifier indicates that a physician started a procedure but terminated it due to extenuating circumstances or patient safety concerns.

Example scenario: An electrophysiologist begins a planned supraventricular tachycardia (SVT) ablation and stops the procedure after patient safety concerns arise or new findings require the physician to terminate the attempt before completion.

Report modifier 53 on the physician claim when a procedure is started and discontinued due to extenuating circumstances or those that threaten the patient’s well-being.

For facility claims, hospitals may use one of the following:

• Modifier 73 (Discontinued before anesthesia)
• Modifier 74 (Discontinued after anesthesia or after the procedure begins)

Important: Always verify payer policies for modifier usage.

Tip 3: Do Not Report a Completed Ablation Code Without a Modifier

If the physician did not complete an ablation, reporting the full CPT^® code without a modifier can lead to compliance issues.

For instance, if the planned procedure was 93653 but the physician was unable to complete the service, reporting 93653 without modifier 53 would be inaccurate.

Instead, report 93653 with modifier 53 to indicate the procedure was discontinued.

Tip 4: Code any Procedure That Was Actually Completed

If the physician performs a different procedure during the same encounter, you can code that service separately if it was completed.

For example, the physician may:

• Begin mapping for an SVT ablation
• Determine the patient requires AV nodal ablation with pacemaker therapy
• Stop the original ablation attempt

If the physician does not perform the pacemaker upgrade during the same session, you may only report the discontinued service.

If they complete the pacemaker upgrade during the same encounter, you may report the pacemaker codes separately, according to CPT^® guidelines. Pacemaker implantation and upgrade codes typically fall within the 33206 (Insertion of new or replacement of permanent pacemaker with transvenous electrode(s); atrial) through 33229 (Removal of permanent pacemaker pulse generator with replacement of pacemaker pulse generator; multiple lead system) range, depending on the device and leads involved.

Always review the operative report carefully to determine which procedures were planned, attempted, and completed.

Tip 5: Documentation Must Clearly Explain Why the Procedure Stopped

Strong documentation is critical when reporting discontinued procedures.

The operative report should describe:

• The original procedure plan
• Steps already performed before stopping
• The clinical reason for discontinuation
• The recommended alternative treatment

For example, documentation may indicate that mapping findings suggested the patient required AV nodal ablation with permanent pacemaker placement, making the original ablation approach inappropriate.

Without clear documentation, payers may deny the claim or request additional records.

Coding Scenario: Attempted Ablation

A patient presents for a planned supraventricular tachycardia ablation. The electrophysiologist begins the procedure and performs intracardiac mapping. During the study, the physician determines that the patient actually requires AV nodal ablation with a dual-chamber pacemaker upgrade. The physician terminates the planned ablation procedure and schedules the patient for the more appropriate intervention at a later date.

Solution: Report 93653 with modifier 53 to reflect that the planned ablation was begun but discontinued before completion.

Do not report an AV nodal ablation or pacemaker code if those procedures were not performed during the encounter.

Documentation should include: the intended ablation procedure, the stage at which the procedure stopped, clinical findings that prompted termination, and the revised treatment plan.

Key Takeaway

When the physician stops an ablation attempt because they determine the patient requires a different or more extensive procedure, you must determine whether the procedure was started but discontinued or never performed.

Ask these key questions:

• Did the physician begin the ablation procedure?
• Why was the procedure discontinued?
• Was another procedure completed during the encounter?

If the ablation began but could not be completed, report the appropriate ablation code with modifier 53 on the physician claim (or the appropriate facility modifier).

Careful review of the EP report and clear physician documentation are essential to ensure compliant coding and accurate reimbursement.

Suzanne Burmeister, BA, MPhil, Medical Writer and Editor