[Limits and scopes of invasive risk stratification. Do we still need programmed ventricular stimulation?]

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Context:

• Patients with ischemic heart disease (ICM), dilated (DCM), hypertrophic (HCM), or arrhythmogenic right ventricular cardiomyopathy (ARVCM) have a high risk of sudden cardiac death (SCD).
• Internal cardioverter defibrillators (ICDs) treat ventricular tachyarrhythmias causing SCD, but many high-risk patients do not require them.
• Accurate risk stratification markers are needed to avoid unnecessary ICD implantation due to risks, inconvenience, and costs.

Purpose:

• To evaluate the prognostic ability of programmed ventricular stimulation (PVS) in stratifying SCD risk across various cardiomyopathies.
• To highlight the limitations of PVS, particularly its modest prognostic value and poor negative predictive value in certain patient groups.
• To explore future directions for improving SCD risk stratification, including combining PVS with noninvasive parameters and its role in guiding ablation therapy.

Summary:

• Programmed ventricular stimulation (PVS) is used to assess sudden cardiac death (SCD) risk in patients with ICM, DCM, HCM, and ARVCM.
• PVS shows some utility in ICM patients with reduced ejection fraction (30-40%), identifying those at higher SCD risk.
• The prognostic value of PVS is less clear in DCM, HCM, and ARVCM, as arrhythmia inducibility does not consistently correlate with risk, and noninducibility does not guarantee a good prognosis.

Impact:

• Current German guidelines provide class IIb recommendations for PVS in specific ICM, HCM, or ARVCM patients, acknowledging its uncertainties.
• Future research should focus on integrating PVS with noninvasive markers to enhance prognostic accuracy.
• Expanding PVS to guide ventricular arrhythmia ablation could potentially reduce SCD risk in affected patients.