Management of Dysrhythmias During ESWL in Patients with Cardiac Devices
For patients with cardiac implantable electronic devices (CIEDs) undergoing ESWL, avoid focusing the lithotripsy beam near the pulse generator, consider preoperative disabling of atrial pacing if the system triggers on the R-wave, ensure continuous ECG monitoring with immediate availability of temporary pacing and defibrillation equipment, and suspend antitachyarrhythmia functions in ICD patients before the procedure 1.
Preoperative Preparation for CIED Patients
Device Assessment and Programming
- Interrogate the device to determine current settings and pacing dependency 2
- Suspend antitachyarrhythmia functions in ICD patients to prevent inappropriate shocks from electromagnetic interference (EMI) 1
- Consider disabling atrial pacing if the lithotripsy system triggers on the R-wave, as this can interfere with proper device function 2, 1
- Determine pacing dependency through history of symptomatic bradyarrhythmia, prior AV nodal ablation, or inadequate escape rhythm 2
Equipment Readiness
- Position temporary pacing and defibrillation equipment at bedside before starting 2, 1
- Ensure external defibrillation pads are available and positioned away from the pulse generator if needed 2, 1
Intraoperative Management
Monitoring Requirements
Conduct continuous ECG monitoring per ASA standards with peripheral pulse monitoring (pulse oximetry, arterial line, or manual palpation) 2, 1. This dual monitoring approach is critical because EMI can cause artifact on ECG that masks the true cardiac rhythm.
Lithotripsy-Specific Precautions
- Position the lithotripsy beam away from the pulse generator - maintain maximum distance between shock wave focus and device 2, 1
- Monitor for device dysfunction during treatment, as shock waves can be sensed by CIEDs 1
- For R-wave triggered systems, atrial pacing should be disabled preoperatively to prevent triggering conflicts 2, 1
Managing Arrhythmias in Non-CIED Patients
The most recent EAU guidelines note that dysrhythmias occur in approximately 1% of ESWL cases 3. When arrhythmias develop during ESWL in patients without CIEDs:
- Immediately pause treatment for 2 minutes to allow rhythm to normalize 4
- If arrhythmia recurs upon resuming, rotate patient position 15-20 degrees away from original position 4
- This maneuver eliminates arrhythmias in approximately 55% of cases and reduces them to minor unsustained forms in another 20% 4
- If arrhythmia persists after repositioning, implement ECG-gated triggering to synchronize shock waves with the refractory phase of the cardiac cycle 5, 6
Risk Factors for ESWL-Induced Arrhythmias
Arrhythmias occur more frequently with:
- Lower BMI (shock waves reach heart more easily) 4
- Younger age 4
- Right-sided stones 4
- Renal stones (versus ureteral stones) 6
- General anesthesia (38% arrhythmia rate) compared to regional (14%) or IV sedation (27%) 6
Postoperative Management
Device Restoration
Immediately interrogate and restore CIED function in the postoperative period before discharge to unmonitored settings 1. Failure to reactivate antitachyarrhythmia therapies has resulted in sudden death 7.
Continued Monitoring
- Continuously monitor cardiac rate and rhythm with backup pacing/defibrillation immediately available throughout the immediate postoperative period 1
- Maintain monitoring for 24-48 hours until hemodynamics are stable 8
Critical Pitfalls to Avoid
- Never discharge a patient with an ICD without reactivating antitachyarrhythmia functions - this has caused preventable deaths 7
- Do not rely solely on ECG monitoring during ESWL in CIED patients - use peripheral pulse monitoring as EMI creates artifact 2, 1
- Avoid assuming newer lithotripters eliminate all risks - while the 2025 EAU guidelines suggest newer devices may reduce reprogramming needs, technical precautions remain essential 3
- Do not continue treatment through sustained arrhythmias - pause, reposition, or implement ECG gating 4, 5
Special Consideration: Intracardiac Lithotripsy
Recent 2025 data shows that intravascular lithotripsy (IVL) used in cardiac catheterization can induce intracardiac potentials that are sensed by pacemakers, causing pacing inhibition in 100% of cases tested, with 20.6% of pulses capturing the ventricle 9. This represents a distinct concern for patients requiring both ESWL and interventional cardiac procedures, though the mechanisms differ (external shock waves versus intravascular spark discharge).