Use of Cardiac Pacemakers and Antiarrythmia Devices: ACC/AHA Guidelines Summary

Transcription

1 A/AHA ardiology Guideline Summaries Volume 101 Number 101 raunwald: Heart Disease: A Textbook of ardiovascular Medicine, 6e. Use of ardiac Pacemakers and Antiarrythmia Devices: A/AHA Guidelines Summary Thomas H. Lee An American ollege of ardiology/american Heart Association (A/ AHA) task force updated guidelines for the implantation of cardiac pacemakers and antiarrhythmia devices in [1] These guidelines evaluate potential indications for the implantation of pacemakers and antiarrhythmic devices. The guidelines use the same system as other guidelines from these organizations; i.e., they divide them into classes according to their appropriateness. lass signifies general agree ment that the device or therapy is indicated. lass indicates a divergence of opinion with respect to their usefulness, with lass a favoring and lass b not favoring usefulness. The level of evidence to support each position is rated on a scale from A to (see Electrocardiography: A/AHA Guidelines Summary), in which "A" indicates that data were derived from multiple randomized trials involving a large number of individuals, "" indicates that data were derived from a limited number of trials involv ing a relatively small number of patients or from well-designed obser vational studies, and "" indicates that expert consensus was the primary source of the recommendation. NDATONS FOR PERMANENT PANG (Table G-1) Acquired Atrioventricular lock For patients with acquired atrioventricular (AV), bifascicular or trifascicular, or sinus node dysfunction, permanent pacing was considered appropri ate when the abnormality caused complications and was not precipi tated by a drug that could be discontinued. Examples of complications include symptomatic bradycardia, congestive heart failure, and confu sional states. Permanent pacing was also deemed appropriate for asymptomatic patients with a high risk for the subsequent develop ment of complications, such as patients with complete heart and periods of asystole of 3 seconds or more or a slow escape rate or patients with bifascicular or trifascicular with intermittent third- degree AV. For patients with first-degree AV who have symptoms sug gestive of pacemaker syndrome, these guidelines include a new indi cation for permanent pacing that is considered equivocal but sup ported by some data (lass a). Patients with pacemaker syndrome need a dual-chamber pacemaker to restore normal AV synchrony. A lass b indication for permanent pacing was described for patients with a prolonged PR interval and drug-refractory dilated cardiomyopa thy if acute hemodynamic studies demonstrate the benefit of pacing. ndications for permanent pacing for patients who do not have symptoms or complications are less certain. n asymptomatic patients, complete heart with a ventricular escape rate of 40 or more beats/min or type seconddegree AV was considered an equivocal (lass a) indication for permanent pacing. ifascicular or trifascicular in patients with syncope was also not a clear indica tion for permanent pacing but was regarded as acceptable if other possible causes of syncope cannot be identified. Pacemakers were explicitly discouraged for patients with mild asymptomatic conduction abnormalities, such as type second-degree AV at the supra- His level, fascicular with no or only a first-degree AV, and sinus node dysfunction. Symptoms do not play as important a role in determination of the appropriateness of permanent pacing in patients with acute myocar dial infarction because of the poor prognosis and high incidence of sudden death in postinfarction patients with conduction system distur bances. The A/AHA task force emphasized that the requirement for temporary pacing after acute myocardial infarction is not in itself an indication for permanent pacing (see Guidelines to hap. 35 for guidelines on temporary pacing in acute myocardial infarction). How ever, permanent pacemakers were considered appropriate for patients with persistent advanced-degree AV or transient infranodal AV and associated bundle branch. The usefulness of electro physiology study to determine the site of was acknowledged. The usefulness of permanent pacemakers for patients with advanced at the AV node was less clear (lass ), but permanent pacing was discouraged if the sole indication was transient AV conduction disturbances or left anterior hemi.

2 The A/AHA guidelines also defined explicit criteria for the ap propriateness of permanent pacing in patients with hypersensitive ca rotid sinus and neurovascular syndromes. The only lass indication was recurrent syncope [2] associated with clear, spontaneous events provoked by carotid sinus stimulation. n such patients, minimal ca rotid sinus pressure should induce asystole of 3 seconds or more in the absence of medications that depress the sinus node. Recommendations were also included for the use of permanent pacemakers for termination of tachyarrhythmias. Antitachycardia de vices include permanent pacemakers that can be programmed to interrupt reentrant arrhythmias or prevent their occurrence, as well as automatic defibrillator devices. The A/AHA guidelines stressed that these devices should be implanted only after careful evaluation by experienced electrophysiologists. Permanent pacemakers were considered appropriate for use for recurrent supraventricular tachycardias in patients who were sympto matic and whose arrhythmias could not be controlled with drug ther apy or catheter ablation. For patients with symptomatic ventricular tachycardia, permanent pacemakers were considered appropriate as part of an automatic defibrillator system. For patients with hypertrophic cardiomyopathy or dilated cardiomy opathy, clearly appropriate indications for permanent pacemakers were similar to those for patients without these conditions. The task force thought there was some evidence to support the use of dual- chamber or right ventricular pacemakers in some patients with medi cally refractory, symptomatic hypertrophic cardiomyopathy and signifi cant resting or provoked left ventricular outflow obstruction (lass b). Similarly, permanent pacemakers for patients with symptomatic, drug- refractory dilated cardiomyopathy with a prolonged PR interval were considered to be possibly appropriate when acute hemodynamic stud ies demonstrated hemodynamic benefit from pacing. For patients who have undergone cardiac transplantation, permanent pacemakers were considered appropriate when the patients had symptomatic bradyar rhythmias that were not expected to resolve. The guidelines offer general recommendations on the type of per manent pacemaker most appropriate for specific patient subsets but noted that technologies are evolving quickly and prospective random ized data are few. TALE G-1 -- A/AHA GUDELNES FOR PERMANENT PANG * ssue lass Recommendation Level of Evidence Permanent pacing in acquired AV Third-degree AV at any anatomical level associated with any one of the following conditions: radycardia with symptoms presumed to be due to AV Arrhythmias and other medical conditions that require drugs that result in symptomatic bradycardia Documented periods of asystole of 3.0 sec or any escape rate of < 40 beats/min in awake, symptom-free patients After catheter ablation of the AV junction Postoperative AV that is not expected to resolve Neuromuscular diseases with AV such as myotonic muscular dystrophy, Kearns- Sayre syndrome, Erb's dystrophy (limb-girdle), and,,

3 TALE G-1 -- A/AHA GUDELNES FOR PERMANENT PANG * ssue lass Recommendation Level of Evidence Permanent pacing in chronic bifascicular and trifascicular a peroneal muscular atrophy Second-degree AV, regardless of the type or site of, with associated symptomatic bradycardia Asymptomatic third-degree AV at any anatomical site with average awake ventricular rates of 40 beats/min or faster Asymptomatic type seconddegree AV Asymptomatic type seconddegree AV at the intra- or infra-his levels found incidentally at electrophysiological study performed for other indications First-degree AV with symptoms suggestive of pacemaker syndrome and documented alleviation of symptoms with temporary AV pacing b Marked first-degree AV (> 0.30 sec) in patients with LV dysfunction and symptoms of congestive heart failure in whom a shorter AV interval results in hemodynamic improvement, presumably by decreasing left atrial filling pressure a Asymptomatic first-degree AV Asymptomatic type 1 seconddegree AV at the supra- His (AV node) level or not known to be intra- or infra- Hisian AV expected to resolve and unlikely to recur (e.g., drug toxicity, Lyme disease) ntermittent third-degree AV Type second-degree AV Syncope not proved to be due to AV when other likely causes have been excluded, specifically VT ncidental finding at electrophysiological study of markedly prolonged H-V interval (> 100 msec) in asymptomatic patients ncidental finding at,,

4 TALE G-1 -- A/AHA GUDELNES FOR PERMANENT PANG * ssue lass Recommendation Level of Evidence Permanent pacing after the acute phase of myocardial infarction Permanent pacing in sinus node dysfunction b a electrophysiological study of a pacing-induced infra-his that is not physiological Fascicular without AV or symptoms Fascicular with firstdegree AV without symptoms Persistent second-degree AV in the His-Purkinje system with a bilateral bundle branch or third-degree AV within or below the His-Purkinje system after acute M Transient advanced (secondor third-degree) infranodal AV and associated bundle branch. f the site of is uncertain, an electrophysiological study may be necessary Persistent and symptomatic second- or third-degree AV Persistent second- or thirddegree AV at the AV node level Transient AV in the absence of intraventricular conduction defects Transient AV in the presence of isolated left anterior fascicular Acquired left anterior in the absence of AV Persistent first-degree AV in the presence of a bundle branch that is old or age indeterminate Sinus node dysfunction with documented symptomatic bradycardia, including frequent sinus pauses that produce symptoms Symptomatic chronotropic incompetence Sinus node dysfunction occurring spontaneously or as a result of necessary drug therapy, with a heart rate of <40 beats/min when a clear association between significant symptoms consistent with bradycardia and the actual presence of bradycardia has

5 TALE G-1 -- A/AHA GUDELNES FOR PERMANENT PANG * ssue lass Recommendation Level of Evidence Permanent pacemakers that automatically detect and pace to terminate tachycardias Pacing indications to prevent tachycardia b b a b not been documented n minimally symptomatic patients, chronic heart rate of less than 30 beats/min while awake Sinus node dysfunction in asymptomatic patients, including those in whom substantial sinus bradycardia (heart rate of <40 beats/min) is a consequence of long-term drug treatment Sinus node dysfunction in patients with symptoms suggestive of bradycardia that are clearly documented as not associated with a slow heart rate Sinus node dysfunction with symptomatic bradycardia from nonessential drug therapy Symptomatic recurrent supraventricular tachycardia that is reproducibly terminated by pacing after drugs and catheter ablation fail to control the arrhythmia or produce intolerable side effects Symptomatic recurrent sustained VT as part of an automatic defibrillator system Recurrent supraventricular tachycardia or atrial flutter that is reproducibly terminated by pacing as an alternative to drug therapy or ablation Tachycardias frequently accelerated or converted to fibrillation by pacing The presence of accessory pathways with the capacity for rapid anterograde conduction regardless of whether the pathways participate in the mechanism of the tachycardia Sustained pause-dependent VT, with or without a prolonged QT, in which the efficacy of pacing is thoroughly documented High-risk patients with congenital long QT syndrome AV reentrant or AV node reentrant supraventricular tachycardia not responsive to medical or ablative therapy

6 TALE G-1 -- A/AHA GUDELNES FOR PERMANENT PANG * ssue lass Recommendation Level of Evidence Permanent pacing in hypersensitive carotid sinus syndrome and neurally mediated syncope Hypertrophic cardiomyopathy a b b Prevention of symptomatic, drug-refractory, recurrent atrial fibrillation Frequent or complex ventricular ectopic activity without sustained VT in the absence of long QT syndrome Long QT syndrome from reversible causes Recurrent syncope caused by carotid sinus stimulation; minimal carotid sinus pressure induces ventricular asystole of >3-sec duration in the absence of any medication that depresses the sinus node or AV conduction Recurrent syncope without clear, provocative events and with a hypersensitive cardioinhibitory response Syncope of unexplained origin when major abnormalities of sinus node function or AV conduction are discovered or provoked in electrophysiological studies Neurally mediated syncope with significant bradycardia reproduced by a head-up tilt with or without isoproterenol or other provocative maneuvers A hyperactive cardioinhibitory response to carotid sinus stimulation in the absence of symptoms A hyperactive cardioinhibitory response to carotid sinus stimulation in the presence of vague symptoms such as dizziness, lightheadedness, or both Recurrent syncope, lightheadedness, or dizziness in the absence of a hyperactive cardioinhibitory response Situational vasovagal syncope in which avoidance behavior is effective lass indications for sinus node dysfunction or AV as previously described Medically refractory, symptomatic hypertrophic cardiomyopathy with significant resting or provoked LV outflow obstruction

7 Dilated cardiomyopathy TALE G-1 -- A/AHA GUDELNES FOR PERMANENT PANG * ssue lass Recommendation Level of Evidence b Patients who are asymptomatic or medically controlled Symptomatic patients without evidence of LV outflow obstruction lass indications for sinus node dysfunction or AV as previously described Symptomatic, drug-refractory dilated cardiomyopathy with a prolonged PR interval when acute hemodynamic studies have demonstrated a hemodynamic benefit of pacing Asymptomatic dilated cardiomyopathy Symptomatic dilated cardiomyopathy when patients are rendered asymptomatic by drug therapy Symptomatic ischemic cardiomyopathy ardiac transplantation Symptomatic bradyarrhythmias/chronotropic incompetence not expected to resolve and other lass indications for permanent pacing AV = atrioventricular; LV = left ventricular; M = myocardial infarction; VF = ventricular fibrillation; VT = ventricular tachycardia. From Gregoratos G, heitlin M, onill A, et al: A/AHA guidelines for implantation of cardiac pacemakers and antiarrhythmia devices. A report of the American ollege of ardiology/american Heart Association Task Force on Practice Guidelines (ommittee on Pacemaker mplantation). J Am oll ardiol 31: , *For definition of classes and levels of evidence, see guildelines AHA/A guidelines for Electrocardiography. MPLANTALE ARDOVERTER-DEFRLLATOR THERAPY The enthusiasm for implanting cardioverter-defibrillator devices has been increasing because of disappointing data on the lack of impact of antiarrhythmic medications on survival and data showing low rates of sudden cardiac death and improved quality of life after device implantation. mplantable cardioverter-defibrillators (Ds) can be combined with drug therapy or ablation techniques applied at surgery or percutaneously via catheter techniques. Ablation techniques are in particularly rapid evolution, which hinders the ability to develop formal guidelines for their appropriateness and relative merits in comparison to alternative strategies. Ds are now regarded as clearly appropriate therapy for patients who have had cardiac arrest as a result of ventricular fibrillation or ventricular tachycardia without a transient or reversible cause, as well as for patients with spontaneous sustained ventricular tachycardia (Table G-2). The A/AHA guidelines consider Ds appropriate for patients who have electrophysiological studies that suggest ar rhythmia as a likely cause of syncope and other patients with high- risk electrophysiology tests. Ds are not recommended by the A/AHA task force for sev eral groups, including the following: a) Patients for whom a reversible triggering factor for arrhythmia can be identified, such as evolving myocardial infarction or elec trolyte abnormalities.

8 b) Patients with coronary disease without inducible or spontaneous ventricular tachycardia who are undergoing routine coronary ar tery bypass graft surgery. c) Patients with Wolff-Parkinson-White syndrome and ventricular fibrillation secondary to atrial fibrillation. (These patients should undergo catheter or surgical ablation if their accessory pathways are amenable to such treatment.) d) Patients with frequent tachyarrhythmias that may trigger shock therapy. TALE G-2 -- A/AHA GUDELNES FOR MPLANTALE ARDOVERTER-DEFRLLATOR THERAPY * lass Recommendation Level of Evidence b ardiac arrest due to VF or VT not due to a transient or reversible cause Spontaneous sustained VT Syncope of undetermined origin with clinically relevant, hemodynamically significant sustained VT or VF induced at electrophysiological study when drug therapy is ineffective, not tolerated, or not preferred Nonsustained VT with coronary disease, prior M, LV dysfunction, and inducible VF or sustained VT at electrophysiological study that is not suppressible by a class antiarrhythmic drug ardiac arrest presumed to be due to VF when electrophysiological testing is precluded by other medical conditions Severe symptoms attributable to sustained ventricular tachyarrhythmias while awaiting cardiac transplantation Familial or inherited conditions with a high risk for life-threatening ventricular tachyarrhythmias such as long QT syndrome or hypertrophic cardiomyopathy Nonsustained VT with coronary artery disease, prior M, and LV dysfunction and inducible sustained VT or VF at electrophysiological study Recurrent syncope of undetermined etiology in the presence of ventricular dysfunction and inducible ventricular arrhythmias at electrophysiological study when other causes of syncope have been excluded Syncope of undetermined cause in a patient without inducible ventricular tachyarrhythmias ncessant VT or VF LV = left ventricular; M = myocardial infarction; VF = ventricular fibrillation; VT = ventricular tachycardia. From Gregoratos G, heitlin M, onill A, et al: A/AHA guidelines for implantation of cardiac pacemakers and antiarrhythmia devices. A report of the American ollege of ardiology/american Heart Association Task Force on Practice Guidelines (ommittee on Pacemaker mplantation). J Am oll ardiol 31: , *For definition of classes and levels of evidence, see guildelines AHA/A guidelines for Electrocardiography. A References 1. Gregoratos G, heitlin M, onill A, et al: A/AHA guidelines for implanta tion of cardiac pacemakers and antiarrhythmia devices. A report of the Amer ican ollege of ardiology/american Heart Association Task Force on Prac tice Guidelines (ommittee on Pacemaker mplantation). J Am oll ardiol 31: , onnolly SJ, Sheldon R, Roberts RS, Gent M: The North American Vasova gal Pacemaker Study (VPS): A randomized trial of permanent cardiac pacing for the prevention of vasovagal syncope. J Am oll ardiol 36:16-20, 1999.