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Santangeli P, Rame JE, Birati EY, Marchlinski FE. Management of Ventricular Arrhythmias in Patients With Advanced Heart Failure. J Am Coll Cardiol 2017; 69:1842. 22. Pacifico A, Hohnloser SH, Williams JH, et al. Prevention of implantable-defibrillator shocks by treatment with sotalol. d,l-Sotalol Implantable Cardioverter-Defibrillator Study Group. N Engl J Med 1999; 340:1855. 23. Connolly SJ, Dorian P, Roberts RS, et al. Comparison of beta-blockers, amiodarone plus beta- blockers, or sotalol for prevention of shocks from implantable cardioverter defibrillators: the OPTIC Study: a randomized trial. JAMA 2006; 295:165. 24. Dorian P, Borggrefe M, Al-Khalidi HR, et al. Placebo-controlled, randomized clinical trial of azimilide for prevention of ventricular tachyarrhythmias in patients with an implantable cardioverter defibrillator. Circulation 2004; 110:3646. 25. Singer I, Al-Khalidi H, Niazi I, et al. Azimilide decreases recurrent ventricular tachyarrhythmias in patients with implantable cardioverter defibrillators. J Am Coll Cardiol 2004; 43:39. 26. K hlkamp V, Mewis C, Mermi J, et al. Suppression of sustained ventricular tachyarrhythmias: a comparison of d,l-sotalol with no antiarrhythmic drug treatment. J Am Coll Cardiol 1999; 33:46. https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 23/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate 27. Ferreira-Gonz lez I, Dos-Subir L, Guyatt GH. Adjunctive antiarrhythmic drug therapy in patients with implantable cardioverter defibrillators: a systematic review. Eur Heart J 2007; 28:469. 28. Randomized antiarrhythmic drug therapy in survivors of cardiac arrest (the CASCADE Study). The CASCADE Investigators. Am J Cardiol 1993; 72:280. 29. Sim I, McDonald KM, Lavori PW, et al. Quantitative overview of randomized trials of amiodarone to prevent sudden cardiac death. Circulation 1997; 96:2823. 30. Mason JW. A comparison of seven antiarrhythmic drugs in patients with ventricular tachyarrhythmias. Electrophysiologic Study versus Electrocardiographic Monitoring Investigators. N Engl J Med 1993; 329:452. 31. Haverkamp W, Martinez-Rubio A, Hief C, et al. Efficacy and safety of d,l-sotalol in patients with ventricular tachycardia and in survivors of cardiac arrest. J Am Coll Cardiol 1997; 30:487. 32. Kovoor P, Eipper V, Byth K, et al. Comparison of sotalol with amiodarone for long-term treatment of spontaneous sustained ventricular tachyarrhythmia based on coronary artery disease. Eur Heart J 1999; 20:364. 33. Man KC, Williamson BD, Niebauer M, et al. Electrophysiologic effects of sotalol and amiodarone in patients with sustained monomorphic ventricular tachycardia. Am J Cardiol 1994; 74:1119. 34. Boriani G, Lubinski A, Capucci A, et al. A multicentre, double-blind randomized crossover comparative study on the efficacy and safety of dofetilide vs sotalol in patients with inducible sustained ventricular tachycardia and ischaemic heart disease. Eur Heart J 2001; 22:2180. 35. Baquero GA, Banchs JE, Depalma S, et al. Dofetilide reduces the frequency of ventricular arrhythmias and implantable cardioverter defibrillator therapies. J Cardiovasc Electrophysiol 2012; 23:296. 36. Greenspan AM, Spielman SR, Horowitz LN. Combination antiarrhythmic drug therapy for ventricular tachyarrhythmias. Pacing Clin Electrophysiol 1986; 9:565. 37. Cronin EM, Bogun FM, Maury P, et al. 2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias. Heart Rhythm 2020; 17:e2. 38. Willems S, Tilz RR, Steven D, et al. Preventive or Deferred Ablation of Ventricular Tachycardia in Patients With Ischemic Cardiomyopathy and Implantable Defibrillator (BERLIN VT): A Multicenter Randomized Trial. Circulation 2020; 141:1057. https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 24/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate 39. Di Biase L, Santangeli P, Burkhardt DJ, et al. Endo-epicardial homogenization of the scar versus limited substrate ablation for the treatment of electrical storms in patients with ischemic cardiomyopathy. J Am Coll Cardiol 2012; 60:132. 40. Ja s P, Maury P, Khairy P, et al. Elimination of local abnormal ventricular activities: a new end point for substrate modification in patients with scar-related ventricular tachycardia. Circulation 2012; 125:2184. 41. Vergara P, Trevisi N, Ricco A, et al. Late potentials abolition as an additional technique for reduction of arrhythmia recurrence in scar related ventricular tachycardia ablation. J Cardiovasc Electrophysiol 2012; 23:621. 42. Tanawuttiwat T, Nazarian S, Calkins H. The role of catheter ablation in the management of ventricular tachycardia. Eur Heart J 2016; 37:594. 43. Stevenson WG, Tedrow UB, Reddy V, et al. Infusion Needle Radiofrequency Ablation for Treatment of Refractory Ventricular Arrhythmias. J Am Coll Cardiol 2019; 73:1413. 44. Di Biase L, Burkhardt JD, Lakkireddy D, et al. Ablation of Stable VTs Versus Substrate Ablation in Ischemic Cardiomyopathy: The VISTA Randomized Multicenter Trial. J Am Coll Cardiol 2015; 66:2872. 45. Romero J, Cerrud-Rodriguez RC, Di Biase L, et al. Combined Endocardial-Epicardial Versus Endocardial Catheter Ablation Alone for Ventricular Tachycardia in Structural Heart Disease: A Systematic Review and Meta-Analysis. JACC Clin Electrophysiol 2019; 5:13. 46. Sarkozy A, Tokuda M, Tedrow UB, et al. Epicardial ablation of ventricular tachycardia in ischemic heart disease. Circ Arrhythm Electrophysiol 2013; 6:1115. 47. Piers SR, Tao Q, de Riva Silva M, et al. CMR-based identification of critical isthmus sites of ischemic and nonischemic ventricular tachycardia. JACC Cardiovasc Imaging 2014; 7:774. 48. Njeim M, Yokokawa M, Frank L, et al. Value of Cardiac Magnetic Resonance Imaging in Patients With Failed Ablation Procedures for Ventricular Tachycardia. J Cardiovasc Electrophysiol 2016; 27:183. 49. Reddy VY, Reynolds MR, Neuzil P, et al. Prophylactic catheter ablation for the prevention of defibrillator therapy. N Engl J Med 2007; 357:2657. 50. Stevenson WG, Wilber DJ, Natale A, et al. Irrigated radiofrequency catheter ablation guided by electroanatomic mapping for recurrent ventricular tachycardia after myocardial infarction: the multicenter thermocool ventricular tachycardia ablation trial. Circulation 2008; 118:2773. 51. Al-Khatib SM, Daubert JP, Anstrom KJ, et al. Catheter ablation for ventricular tachycardia in patients with an implantable cardioverter defibrillator (CALYPSO) pilot trial. J Cardiovasc https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 25/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate Electrophysiol 2015; 26:151. 52. Sapp JL, Wells GA, Parkash R, et al. Ventricular Tachycardia Ablation versus Escalation of Antiarrhythmic Drugs. N Engl J Med 2016; 375:111. 53. Kuck KH, Schaumann A, Eckardt L, et al. Catheter ablation of stable ventricular tachycardia before defibrillator implantation in patients with coronary heart disease (VTACH): a multicentre randomised controlled trial. Lancet 2010; 375:31. 54. Kuck KH, Tilz RR, Deneke T, et al. Impact of Substrate Modification by Catheter Ablation on Implantable Cardioverter-Defibrillator Interventions in Patients With Unstable Ventricular Arrhythmias and Coronary Artery Disease: Results From the Multicenter Randomized Controlled SMS (Substrate Modification Study). Circ Arrhythm Electrophysiol 2017; 10. 55. Ha AH, Ham I, Nair GM, et al. Implantable cardioverter-defibrillator shock prevention does not reduce mortality: a systemic review. Heart Rhythm 2012; 9:2068. 56. Tung R, Xue Y, Chen M, et al. First-Line Catheter Ablation of Monomorphic Ventricular Tachycardia in Cardiomyopathy Concurrent With Defibrillator Implantation: The PAUSE-SCD Randomized Trial. Circulation 2022; 145:1839. 57. Della Bella P, Baratto F, Vergara P, et al. Does Timing of Ventricular Tachycardia Ablation Affect Prognosis in Patients With an Implantable Cardioverter Defibrillator? Results From the Multicenter Randomized PARTITA Trial. Circulation 2022; 145:1829. 58. Anderson RD, Ariyarathna N, Lee G, et al. Catheter ablation versus medical therapy for treatment of ventricular tachycardia associated with structural heart disease: Systematic review and meta-analysis of randomized controlled trials and comparison with observational studies. Heart Rhythm 2019; 16:1484. 59. Martinez BK, Baker WL, Konopka A, et al. Systematic review and meta-analysis of catheter ablation of ventricular tachycardia in ischemic heart disease. Heart Rhythm 2020; 17:e206. 60. Palaniswamy C, Kolte D, Harikrishnan P, et al. Catheter ablation of postinfarction ventricular tachycardia: ten-year trends in utilization, in-hospital complications, and in-hospital mortality in the United States. Heart Rhythm 2014; 11:2056. 61. Santangeli P, Frankel DS, Tung R, et al. Early Mortality After Catheter Ablation of Ventricular Tachycardia in Patients With Structural Heart Disease. J Am Coll Cardiol 2017; 69:2105. 62. Vergara P, Tzou WS, Tung R, et al. Predictive Score for Identifying Survival and Recurrence Risk Profiles in Patients Undergoing Ventricular Tachycardia Ablation: The I-VT Score. Circ Arrhythm Electrophysiol 2018; 11:e006730. 63. Santangeli P, Muser D, Zado ES, et al. Acute hemodynamic decompensation during catheter ablation of scar-related ventricular tachycardia: incidence, predictors, and impact on https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 26/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate mortality. Circ Arrhythm Electrophysiol 2015; 8:68. 64. Tzou WS, Tung R, Frankel DS, et al. Ventricular Tachycardia Ablation in Severe Heart Failure: An International Ventricular Tachycardia Ablation Center Collaboration Analysis. Circ Arrhythm Electrophysiol 2017; 10. 65. Turagam MK, Vuddanda V, Atkins D, et al. 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Role of cardiac sympathetic denervation in ventricular tachycardia: A meta-analysis. Pacing Clin Electrophysiol 2020; 43:828. 71. Cuculich PS, Schill MR, Kashani R, et al. Noninvasive Cardiac Radiation for Ablation of Ventricular Tachycardia. N Engl J Med 2017; 377:2325. 72. Robinson CG, Samson PP, Moore KMS, et al. Phase I/II Trial of Electrophysiology-Guided Noninvasive Cardiac Radioablation for Ventricular Tachycardia. Circulation 2019; 139:313. 73. Neuwirth R, Cvek J, Knybel L, et al. Stereotactic radiosurgery for ablation of ventricular tachycardia. Europace 2019; 21:1088. 74. Lloyd MS, Wight J, Schneider F, et al. Clinical experience of stereotactic body radiation for refractory ventricular tachycardia in advanced heart failure patients. Heart Rhythm 2020; 17:415. Topic 1040 Version 52.0 https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 27/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate GRAPHICS Algorithm for initial treatment of SMVT in responsive patients with a pulse SMVT: sustained monomorphic ventricular tachycardia; CV: cardioversion. Hemodynamically unstable patients have evidence of hemodynamic compromise, such as hypotension, altered mental status, chest pain, or heart failure. Hemodynamically stable patients should have none of these findings. Initial choice of pharmacologic agents includes: Intravenous lidocaine (1 to 1.5 mg/kg [typically 75 to 100 mg] at a rate of 25 to 50 mg/minute; lower doses of 0.5 to 0.75 mg/kg can be repeated every 5 to 10 minutes as needed), which may be more effective in the setting of acute myocardial ischemia or infarction Intravenous procainamide (20 to 50 mg/minute until arrhythmia terminates or a maximum dose of 17 mg/kg is administered) Intravenous amiodarone (150 mg IV over 10 minutes, followed by 1 mg/minute for the next six hours; bolus can be repeated if VT recurs) Electrical cardioversion should be synchronized if possible, using 100-joule biphasic shock or 200- joule monophasic shock. If first shock is unsuccessful, energy level should be escalated on subsequent shocks. https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 28/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate Conditions associated with SMVT include myocardial ischemia, electrolyte disturbances (eg, hypokalemia, hypomagnesemia), drug-related proarrhythmia, and heart failure. Graphic 108831 Version 1.0 https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 29/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate Adult cardiac arrest algorithm https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 30/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 31/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate Reprinted with permission. Highlights of the 2020 American Heart Association Guidelines for CPR and ECC. Copyright 2020 American Association, Inc. Graphic 129983 Version 9.0 https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 32/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate Amiodarone dosing in adults by indication Indications Loading dose Maintenance dose Atrial arrhythmias Prevention of recurrent PAF Total loading dose: 6 to 10 grams Lowest effective dose, usually 100 to 200 mg orally once per day Pharmacologic Outpatient: Given as 400 to cardioversion of PAF 600 mg orally per day in divided doses with meals Maximum 200 mg orally per day Inpatient: Given as 400 to 1200 mg orally per day in divided doses with meals Pretreatment before elective cardioversion or catheter ablation of AF Total loading dose: 6 to 10 grams orally over 2 to 6 weeks Lowest effective dose, usually 100 to 200 mg orally once per day Given as 400 to 1200 mg orally per day in divided Maximum 400 mg orally per day in most circumstances doses Restoration and maintenance of NSR in critically ill patients with AF Total IV loading dose: 1050 mg Given as 150 mg IV bolus over 10 to 30 minutes, followed by continuous IV Ventricular rate control in critically ill patients with AF and rapid ventricular response infusion at 1 mg per minute for 6 hours, then 0.5 mg per minute for 18 hours* IV infusion (0.5 mg per minute) may need to be extended past 24 hours if unable to transition to oral therapy If amiodarone will be used chronically: Following IV infusion, give 400 to 1200 mg orally per day in divided doses to complete a total (IV plus oral) loading dose of 10 grams; consider overlapping IV and oral amiodarone for 24 to 48 hours Ventricular arrhythmias https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 33/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate Primary and secondary Total oral loading dose: 6 to Maximum 400 mg orally per prevention of SCD in patients with LV 10 grams day in most circumstances Outpatient: 400 to 600 mg orally per day in divided Lowest effective dose, ideally 200 mg or less orally once dysfunction who are not candidates for or refuse ICD implantation doses with meal per day or in divided doses Inpatient: 400 to 1200 mg orally per day in divided doses with meals for 1 to 2 weeks Prevention of ventricular Total loading dose: 6 to 10 Maximum 400 mg orally per arrhythmias in patients with ICDs to decrease risk grams day in most circumstances Outpatient: Given as 400 to 600 mg orally per day in Lowest effective dose, ideally 200 mg or less orally per day of shocks divided doses with meals Inpatient: Given as 400 to 1200 mg orally per day in divided doses with meals until desired dose is achieved Cardiac arrest associated with VF or pulseless VT 300 mg IV or IO rapid bolus with a repeat dose of 150 mg as indicated Upon return of spontaneous circulation follow with an infusion of 1 mg per minute for 6 hours and then 0.5 mg per minute for 18 hours* Electrical (VT) storm and incessant VT in hemodynamically stable Total IV loading dose: 1050 mg If amiodarone is used chronically: Lowest effective dose, ideally 200 mg or less 150 mg IV bolus over 10 minutes, followed by patients orally per day; maximum 400 mg orally per day in most continuous IV infusion at 1 circumstances mg per minute for 6 hours, then 0.5 mg per minute for 18 hours IV infusion (0.5 mg per minute) may need to be extended past 24 hours if unable to transition to oral therapy Additional 150 mg boluses may be given if VT storm recurs https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 34/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate If amiodarone will be used chronically: Following IV infusion 400 to 1200 mg orally per day in divided doses to complete a total (IV plus oral) loading dose of 10 grams. Consider overlapping IV and oral amiodarone for 24-48 hours PAF: paroxysmal atrial fibrillation; AF: atrial fibrillation; NSR: normal sinus rhythm; IV: intravenous; SCD: sudden cardiac death; LV: left ventricular; ICD: implantable cardioverter-defibrillator; VF: ventricular fibrillation; VT: ventricular tachycardia; IO: intraosseous. When administered to critically ill patients with atrial fibrillation and rapid ventricular response, repeated 150 mg boluses can be given over 10 to 30 minutes if needed, but no more than six to eight additional boluses should be administered in any 24-hour period. Typically, patients are given 1 or 2 doses of oral amiodarone prior to discontinuation of the IV infusion. Graphic 117524 Version 5.0 https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 35/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate Electrophysiology study (EPS) tracings showing concealed entrainment (A) Pacing from the distal electrode pair of the mapping/ablation catheter during mapping of sustained ventr tachycardia. On the left side of the figure are the last three stimuli during a train of pacing at a cycle length o milliseconds. Following pacing, the tachycardia (cycle length 430 milliseconds) resumes. The interval from the paced beat to resumption of tachycardia, measured in the distal ablation catheter (Abl d), is just 10 millisecon greater than the tachycardia cycle length. Note that the interval from the pacing stimulus to onset of the QRS is the same as the interval from the local electrogram to the QRS onset when VT resumes after pacing. Note a the paced VT morphology replicates the morphology of the spontaneous tachycardia. This is an example of "concealed entrainment" and implies the catheter is within a critical part of a reentrant circuit. (B) Same site on the ablation catheter (Abl d) during sinus rhythm as shown during VT in figure A. During sinu rhythm, a late potential is present. The vertical line denotes the end of the QRS complex. Delivery of radiofreq energy at this site resulted in termination of VT. The tachycardia was no longer inducible after ablation. Sites this displaying late potentials may be targeted during "substrate-guided ablation." VT: ventricular tachycardia. Graphic 107237 Version 2.0 https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 36/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate Complications of invasive cardiac electrophysiology studies Associated with percutaneous catheterization of veins and arteries Pain Adverse drug reaction Infection/abscess at the catheterization site, sepsis Excessive bleeding, hematoma formation Thrombophlebitis Pulmonary thromboembolism Arterial damage, aortic dissection Systemic thromboembolism Transient ischemic attack/stroke Associated with intracardiac catheters and programmed cardiac stimulation Cardiac chamber or coronary sinus perforation Hemopericardium, cardiac tamponade Atrial fibrillation Ventricular tachycardia/ventricular fibrillation Myocardial infarction Right or left bundle branch block Associated with transcatheter ablation Complete heart block Thromboembolism Vascular access problems (bleeding, infection, hematoma, vascular injury) Cardiac trauma (myocardial perforation, tamponade, valvular damage) Coronary artery thrombosis/myocardial infarction Cardiac arrhythmias Pericarditis Pulmonary vein stenosis Phrenic nerve paralysis Radiation skin burns Possible late malignancy Atrioesophageal fistula https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 37/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate Death resulting from one of the above complications Graphic 63157 Version 4.0 https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 38/39 7/6/23, 3:39 PM Sustained monomorphic ventricular tachycardia in patients with structural heart disease: Treatment and prognosis - UpToDate Contributor Disclosures Alfred Buxton, MD No relevant financial relationship(s) with ineligible companies to disclose. Peter J Zimetbaum, MD Consultant/Advisory Boards: Abbott Medical [Lead extraction]. All of the relevant financial relationships listed have been mitigated. Nisha Parikh, MD, MPH No relevant financial relationship(s) with ineligible companies to disclose. Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence. Conflict of interest policy https://www.uptodate.com/contents/sustained-monomorphic-ventricular-tachycardia-in-patients-with-structural-heart-disease-treatment-and-prognos 39/39