Extravascular ICD Pivotal Study

Pivotal Inclusion Criteria: * Patient has a Class I or IIa indication for implantation of an ICD according to the ACC/AHA/HRS Guidelines \[i\], or ESC guidelines \[ii\]. * Patient is at least 18 years of age and meets age requirements per local law. * Patient is geographically stable and willing and able to complete the study procedures and visits for the duration of the follow-up. \[i\] Al-Khatib SM, Stevenson WG, Ackerman MJ, Bryant WJ, Callans DJ, Curtis AB, Deal BJ, Dickfeld T, Field ME, Fonarow GC, Gillis AM, Hlatky MA, Granger CB, Hammill SC, Joglar JA, Kay GN, Matlock DD, Myerburg RJ, Page RL. 2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias. \[ii\] Priori SG, Blomstrom-Lundqvist C, Mazzanti A, Blom N, Borggrefe M, Camm J, Elliot PM, Fitzsimons D, Hatala R, Hindricks G, Kirchhof P, Kjeldsen K, Kuck KH, Hernandez-Madrid A, Nikolaou N, Norekval TM, Spaulding C, Van Veldhuisen DJ. 2015 ESC guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death. European Heart Journal 2015 36:41 (2793-2867). https://doi.org/10.1093/eurheartj/ehv316 Pivotal Exclusion Criteria: * Patient is unwilling or unable to personally provide Informed Consent. * Patient has indications for bradycardia pacing \[iii\] or Cardiac Resynchronization Therapy (CRT) \[iv\] (Class I, IIa, or IIb indication). * Patient with an existing pacemaker, ICD, or CRT device implant or leads. * Patients with these medical interventions are excluded from participation in the study: * Prior sternotomy * Any prior medical condition or procedure that leads to adhesions in the anterior mediastinal space (i.e., prior mediastinal instrumentation, mediastinitis) * Prior abdominal surgery in the epigastric region * Planned sternotomy * Prior chest radiotherapy Or any other prior/planned medical intervention not listed that precludes their participation in the opinion of the Investigator. * Patient has previous pericarditis that: * Was chronic and recurrent, or * Resulted in pericardial effusion \[v\], or * Resulted in pericardial thickening or calcification \[vi\]. * Patients with these medical conditions or anatomies are excluded from participation in the study: * Hiatal hernia that distorts mediastinal anatomy * Marked sternal abnormality (e.g., pectus excavatum) * Decompensated heart failure * COPD with oxygen dependence * Gross hepatosplenomegaly Or any other known medical condition or anatomy type not listed that precludes their participation in the opinion of the Investigator. * Patients with a medical condition that precludes them from undergoing defibrillation testing: * Severe aortic stenosis * Intracardiac LA or LV thrombus * Severe proximal three-vessel or left main coronary artery disease without revascularization * Hemodynamic instability * Unstable angina * Recent stroke or transient ischemic attack (within the last 6 months) * Known inadequate external defibrillation * LVEF \<20% * LVEDD \>70 mm Or any other known medical condition not listed that precludes their participation in the opinion of the Investigator. * Patient with any evidence of active infection or undergoing treatment for an infection. * Patient is contraindicated from temporary suspension of oral/systemic anticoagulation * Patient with current implantation of neurostimulator or any other chronically implanted device that delivers current in the body. * Patient meets ACC/AHA/HRS or ESC clinical guideline Class III criteria for an ICD (e.g., life expectancy of less than 12 months). * Patient is enrolled or planning to enroll in a concurrent clinical study that may confound the results of this study, without documented pre-approval from a Medtronic study manager. * Patient with any exclusion criteria as required by local law (e.g., age or other). * Pregnant women or breastfeeding women, or women of child bearing potential and who are not on a reliable form of birth regulation method or abstinence. \[iii\] 2015 HRS/EHRA/APHRS/SOLAECE expert consensus statement on optimal implantable cardioverter-defibrillator programming and testing). \[iv\] ACC/AHA/HRS guidelines for Cardiac Resynchronization Therapy. \[v\] As documented on echo or MRI. \[vi\] As documented on CT scan or MRI. Continued Access Inclusion Criteria 1. Patient has a Class I or IIa indication for implantation of an ICD according to the ACC/AHA/HRS Guidelines.\[1\] 2. Patient is willing and able to sign and date the Informed Consent Form for their participation in the study. 3. Patient is at least 18 years of age and meets age requirements per local law. 4. Patient is geographically stable and willing and able to comply with the study procedures and visits for the duration of the follow-up. \[1\] Al-Khatib SM, Stevenson WG, Ackerman MJ, Bryant WJ, Callans DJ, Curtis AB, Deal BJ, Dickfeld T, Field ME, Fonarow GC, Gillis AM, Granger CB, Hammill SC, Hlatky MA, Joglar JA, Kay GN, Matlock DD, Myerburg RJ, Page RL. 2017 AHA/ACC/HRS Guideline for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol. 2018 Oct 2;72(14):e91-e220. doi: 10.1016/j.jacc.2017.10.054. Epub 2018 Aug 16. Review. Erratum in: J Am Coll Cardiol. 2018 Oct 2;72(14):1760. Continued Access Exclusion Criteria 1. Patient has indications for bradycardia pacing\[2\] or Cardiac Resynchronization Therapy (CRT)\[3\] (Class I, IIa, or IIb indication). 2. Patients with an existing pacemaker, ICD, or CRT device or leads. 3. Patients with these medical interventions are excluded from participation in the study: * Prior sternotomy * Any prior medical condition or procedure that leads to adhesions in the anterior mediastinal space (i.e., prior mediastinal instrumentation, mediastinitis) * Prior abdominal surgery in the epigastric region * Planned sternotomy * Prior chest radiotherapy Or any other prior/planned medical intervention not listed that precludes their participation in the opinion of the Investigator. 4. Patients with these medical conditions or anatomies are excluded from participation in the study: * Hiatal hernia that distorts mediastinal anatomy * Marked sternal abnormality (e.g., pectus excavatum that impedes the substernal tunneling path or procedure) * Decompensated heart failure * COPD with oxygen dependence * Gross hepatosplenomegaly Or any other known medical condition or anatomy type not listed that precludes their participation in the opinion of the Investigator. 5. Patients with a medical condition that precludes them from undergoing defibrillation testing: * Severe aortic stenosis * Current Intracardiac LA or LV thrombus * Severe proximal three-vessel or left main coronary artery disease without revascularization * Hemodynamic instability * Unstable angina * Recent stroke or transient ischemic attack (within the last 6 months) * Known inadequate external defibrillation * LVEF \< 20% * LVEDD \>70 mm Or any other known medical condition not listed that precludes their participation in the opinion of the Investigator. 6. Patient with any evidence of active infection or undergoing treatment for an infection. 7. Patient is contraindicated from temporary suspension of oral/systemic anticoagulation. 8. Patient with current implantation of neurostimulator or any other chronically implanted device that delivers current in the body. 9. Patient meets ACC/AHA/HRS or ESC clinical guideline Class III criteria for an ICD (e.g., life expectancy of less than 12 months). 10. Patient is enrolled or planning to enroll in a concurrent clinical study that may confound the results of this study, without documented pre-approval from a Medtronic study manager. 11. Patient with any exclusion criteria as required by local law (e.g., age or other). 12. Pregnant women or breastfeeding women, or women of childbearing potential and who are not on a reliable form of birth regulation method or abstinence\* (\*If required by local law, women of child-bearing potential must undergo a pregnancy test within seven days prior to EV ICD Continued Access Study procedures) \[2\] Wilkoff BL, Fauchier L, Stiles MK, Morillo CA, Al-Khatib SM, Almendral J, Aguinaga L, Berger RD, Cuesta A, Daubert JP, Dubner S, Ellenbogen KA, Mark Estes NA 3rd, Fenelon G, Garcia FC, Gasparini M, Haines DE, Healey JS, Hurtwitz JL, Keegan R, Kolb C, Kuck KH, Marinskis G, Martinelli M, McGuire M, Molina LG, Okumura K, Proclemer A, Russo AM, Singh JP, Swerdlow CD, Teo WS, Uribe W, Viskin S, Wang CC, Zhang S. 2015 HRS/EHRA/APHRS/SOLAECE expert consensus statement on optimal implantable cardioverter-defibrillator programming and testing. Heart Rhythm. 2016 Feb;13(2):e50-86. doi: 10.1016/j.hrthm.2015.11.018. Epub 2015 Dec 1. \[3\] Kusumoto FM, Schoenfeld MH, Barrett C, Edgerton JR, Ellenbogen KA, Gold MR, Goldschlager NF, Hamilton RM, Joglar JA, Kim RJ, Lee R, Marine JE, McLeod CJ, Oken KR, Patton KK, Pellegrini CN, Selzman KA, Thompson A, Varosy PD. 2018 ACC/AHA/HRS Guideline on the Evaluation and Management of Patients With Bradycardia and Cardiac Conduction Delay: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol. 2019 Aug 20;74(7):e51-e156. doi: 10.1016/j.jacc.2018.10.044. Epub 2018 Nov 6. Erratum in: J Am Coll Cardiol. 2019 Aug 20;74(7):1016-1018.