In young patients (<40 years of age) without structural heart disease who have unexplained cardiac arrest, unex- plained near drowning, or recurrent exertional syncope, genetic testing may be important to identify an inherited arrhythmia syndrome as a likely cause.S4.2.6-17 S4.2.6-23 Recommendation-Specific Supportive Text 1. The decision to proceed with genetic testing requires discussion regarding the clinical use of genetic information to be obtained for both the proband and family members, as well as consideration of the important psychological, financial, employment, disability, and life insurance implications of posi- Balancing privacy of health care information for the proband with the right to know for family members, and the ability to provide appropriate communication of information to all potentially affected family mem- bers can be challenging on many levels, including family dynamics, geographic proximity, and access to health care.S4.2.6-25 For these reasons, genetic counseling generally occurs before proceeding with genetic testing, and, from a patient s perspective, is optimally provided by genetic counselors, if avail- able, in collaboration with physicians.S4.2.6-26,S4.2.6-27 A combined approach of genetic counseling with medical guidance may appropriately balance the decision as to whether genetic testing would be beneficial on an individual basis. 4.3. Invasive Testing 4.3.1. Invasive Cardiac Imaging: Cardiac Catheterization or CT Angiography Recommendation for Invasive Imaging: Cardiac Catheterization COR LOE Recommendation I C-EO In patients who have recovered from unexplained SCA, CT or invasive coronary angiography is useful to confirm the presence or absence of ischemic heart disease and guide decisions for myocardial revascularization. Recommendation-Specific Supportive Text 1. Although randomized studies are unavailable, coronary angiography has an important role in establishing or excluding the presence of sig- nificant obstructive ischemic heart disease in patients with SCA or those with life-threatening Recurrent polymorphic VT or VF can be due to ongoing myocardial ischemia that resolves with coronary revascularization. 