Risk Stratification for Sudden Cardiac Death
A Plan for the Future
Sudden cardiac death (SCD) remains a high priority public health problem necessitating a multi-pronged approach for treatment and prevention. Tachyarrhythmic sudden cardiac death (SCD-VT/VF; ie, death attributable to potentially reversible ventricular tachyarrhythmias [ventricular tachycardia (VT) or fibrillation (VF)]), is a major cause of SCD. Accurate assessment of risk for SCD-VT/VF is of critical importance to assist clinical decision-making regarding prescription of preventive therapies that reduce mortality. These therapeutic decisions include adherence to standard medical therapies, often in conjunction with tailored medications, implantable devices, catheter ablation, or heretofore untested treatments, such as spinal cord stimulation.1 In cases in which the therapy is invasive or carries its own risk, such as these latter interventions, each should be based on reliable demonstration of added benefit to the patient.
Pre-emptive risk stratification for SCD-VT/VF has substantial implications to public health for the following reasons: (1) Heart disease remains the number 1 cause of death in the United States, with >600 000 deaths attributable to heart disease annually reported by the National Center for Health Statistics (http://www.cdc.gov/nchs/fastats/deaths.htm); (2) Approximately half of these deaths are estimated to be sudden; (3) Approximately 50% of all SCDs are the first recognized cardiac event; and (4) Only a minority of those who suffer out-of-hospital cardiac arrest will ultimately survive. Although the incidence of VF as a cause of out-of-hospital cardiac arrest is declining, it remains a leading cause.2 The introduction of the implantable cardioverter-defibrillator (ICD)—an effective, but costly therapy—has had meaningful, but limited, population impact on SCD2; thus, there are opportunities for new approaches (Figure) to address SCD. In particular, improved risk stratification techniques that identify individuals at high risk for SCD-VT/VF could have substantial impact,3 saving lives while stewarding medical resources for cases in which they are most effective. Since 2005, annual meetings …