Evaluation and Management of Arrhythmic Risk in Neuromuscular Disorders
Overview
Overview
Top 10 Take-Home Messages
- Shared decision-making among patients, their families, and clinicians is essential whenever diagnostic studies or therapies, particularly those that are invasive, are being utilized or contemplated. Counseling and education may result in patients’ refusal or withdrawal of such measures if inconsistent with their goals of care, and this should be respected.
- Cardiac testing is appropriate in most patients with neuromuscular disorders (NMDs) to evaluate for cardiac involvement. The type of cardiac test and the need for and frequency of repeat testing is governed by the underlying disorder, results of previous or new studies, and the patient’s symptomatic status. It should be noted that skeletal muscle impairment may mask or confound cardiovascular symptoms, requiring heightened vigilance to cardiac involvement and modification of testing.
- Previously published guideline-based indications for cardiovascular implantable electronic device (CIED) use, including cardiac resynchronization therapy (CRT), and for management of cardiomyopathy (CM) and heart failure may be applied in patients with NMDs. For some indications, the level of evidence (LOE) and/or class of recommendation (COR) in the current document have been modified from prior guidelines to reflect the under-representation of patients with NMDs in past studies.
- A patient’s overall prognosis may be affected by the impact of their underlying neuromuscular condition. Condition-specific technical challenges including body habitus (such as kyphoscoliosis), respiratory muscle weakness and sedation-related risks may influence clinical management. These effects may dominate a patient’s clinical picture and prognosis, possibly attenuating the benefit from arrhythmia therapy, particularly CIED implantation, when compared with other patient populations.
- Patients with Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD), and recessive forms of limb-girdle muscular dystrophy (LGMD) rarely develop bradyarrhythmias, but CM, heart failure, and ventricular arrhythmias (VAs) may occur with increased frequency. When indicated, CIED therapy in these patients may pose technical challenges and limited benefit, particularly in those with advanced neuromuscular impairment.
- In addition to established indications, pacemaker implantation or, in selected individuals, pacing-capable implantable cardioverter-defibrillator (ICD) placement is indicated in patients with myotonic dystrophy type 1 (DM1) or type 2 (DM2) who have evidence of abnormal atrioventricular (AV) conduction, marked by PR interval ≥240 ms, QRS duration ≥120 ms, and/or HV interval ≥70 ms, even when asymptomatic.
- Patients with Emery-Dreifuss muscular dystrophy (EDMD) or limb-girdle muscular dystrophy type 1B (LGMD1B) with abnormal AV conduction, including PR interval ≥230 ms, or HV interval ≥70 ms, are at higher risk of arrhythmic events including sudden death, even when asymptomatic. Transvenous (or equivalent pacing-capable) ICD placement is indicated in such patients.
- Patients with mitochondrial myopathies, such as Kearns-Sayre syndrome, are susceptible to developing advanced, distal conduction disease. Pacemaker implantation is indicated in these patients who demonstrate AV conduction abnormalities, particularly if progressive, including fascicular block.
- Initiation of oral anticoagulation in patients with NMDs who develop atrial fibrillation (AF) should be based on established risk criteria (e.g., CHA2DS2-VASc, HAS-BLED in adults). Individuals with EDMD or LGMD1B and AF should be treated with oral anticoagulation regardless of CHA2DS2-VASc score because of the association with atrial standstill and suspected heightened risk of thromboembolism.
- Early but limited experience with gene modification in some heritable diseases has been promising and is now being employed in patients with NMDs. The hope for additional advances must be tempered by the complexity of these therapeutics and the small number of patients with NMDs who qualify for such treatment.
General Principles for Arrhythmic Risk in NMDs
...les for Arrhythmic Risk in NMDs...
Table 1. Genetics, cardiovascular com...
Duchenne, Becker, and Recessive Limb-girdle Muscular Dystrophies
...enne, Becker, and Recessive Limb-girdle Mu...
...ecessive forms (type 2) of LGMDs a...
...nostic testing and risk stratification in Duche...
...ted care of patients with DMD, BMD, or LGMD2 shou...
...atients with DMD, BMD, or LGMD2, guideline-direct...
...tients with DMD, BMD, or LGMD2, cardiac evalua...
...females who are carriers of a pathogenic or l...
...n patients with DMD, BMD, or LGMD2 who ha...
...conduction disorders, and use of pacing or...
In patients with DMD, BMD, or LGMD2, with doc...
...with DMD, BMD, or LGMD2 and third-degr...
...n patients with DMD, BMD, or LGMD2 with an...
...rhythmias in Duchenne, Becker, and rece...
...ts with DMD, BMD, or LGMD2, anticoagulation a...
...n cardiac death, and use of ICDs i...
...n patients with DMD, BMD, or LGMD2 w...
...patients with DMD, BMD, or LGMD2 with an L...
...Rhythm management and CIED in patient...
...3. Clinical scenarios for the management of arrh...
...Clinical scen...
...ario 2 A 31-year-old man with BMD...
...GMD2 C...
Myotonic Dystrophy Types 1 and 2
...ic Dystrophy Types 1 and 2...
...stic testing and risk stratification in DM1...
...re of patients with DM1 or DM2 should be co...
...with DM1 or DM2, cardiac evaluation including phys...
...atients with DM1 or DM2 and cardiac conduc...
...ients with DM1 or DM2 with symptoms consistent w...
...th DM1 or DM2 with symptoms suggestive...
...radycardias, conduction disorders,...
...h DM1 or DM2 with an LVEF ≤35%, sinus rhyt...
...ents with DM1 or DM2 and documented sy...
...with DM1 or DM2 and third-degree or advanced s...
...h DM1 or DM2 and marked first-degr...
...with DM1 or DM2 with HV interval ≥70 ms on E...
...trial arrhythmias in DM1 and D...
...th DM1 or DM2, anticoagulation acc...
..., sudden cardiac death, and use of ICDs in DM1 an...
...ith DM1 or DM2 in whom ICD therapy is...
...s with DM1 or DM2, who are survivors of spont...
...n patients with DM1 or DM2 and an LVEF ≤3...
...with DM1 or DM2 in whom clinically relevan...
...nts with DM1 or DM2 in whom PPM impla...
...re 2. Rhythm management and CIED impl...
...ble 4. Clinical scenarios for the ma...
...s cover different degrees of muscle impairm...
...M1
...ario 1 A 63-year-old man with DM1 and m...
...cenario 2 A 52-year-old man with...
...MD...
Clinical scenario 3 A 72-year-old w...
...enario 4 A 68-year-old woman with DM1 an...
Emery-Dreifuss and Limb-girdle Type 1B Muscular Dystrophy
...s and Limb-girdle Type 1B Muscular Dystrophy...
Diagnostic testing and risk stratification in E...
...nated care of patients with EDMD or L...
...n patients with EDMD or LGMD1B, cardiac ev...
First-degree relatives of patients with...
...patients with EDMD or LGMD1B, who have...
...with EDMD or LGMD1B with symptoms...
...as, conduction disorders, and use of pacing or CR...
...EDMD or LGMD1B with an LVEF ≤35% de...
...s with EDMD or LGMD1B in whom pacing is ind...
...hythmias in EDMD and LGMD1B...
...th EDMD or LGMD1B, anticoagulation is recommen...
...ith EDMD, anticoagulation is recommended...
...cardiac death, and use of ICDs in EDMD and LGMD1B...
...EDMD or LGMD1B in whom ICD therapy is planned,...
...ts with EDMD or LGMD1B who are survivo...
...EDMD or LGMD1B with at least one of the foll...
...with EDMD or LGMD1B with an LVEF ≤35% despi...
...n patients with EDMD or LGMD1B in whom cli...
...n patients with EDMD or LGMD1B with LV...
...h EDMD or LGMD1B with at least one of...
...with EDMD or LGMD1B with symptomatic...
...hythm management and CIED implantat...
...Clinical scenarios for the management of arrhy...
...DMD...
...scenario 1 A 25-year-old man pre...
...nario 2 A 64-year-old man with EDMD2 p...
...inical scenario 3 A 12-year-ol...
LGMD...
...scenario 4 A 42-year-old woman is admit...
...nical scenario 5 A 35-year-old m...
Facioscapulohumeral Muscular Dystrophy
...pulohumeral Muscular Dystrophy...
...esting and risk stratification in FSH...
...with FSHD, cardiac evaluation including ex...
Mitochondrial Myopathies Including Friedreich Ataxia
...opathies Including Friedreich Ataxia...
...gnostic testing and risk stratification in mi...
...e of patients with mitochondrial myopathies...
...patients with mitochondrial myopathies includ...
...s, conduction disorders, and use of pacing or...
...ith mitochondrial myopathies including...
...atients with mitochondrial myopath...
...patients with FA with an LVEF ≤35% desp...
...ents with mitochondrial myopathies including F...
...as in mitochondrial myopathies including FA...
In patients with mitochondrial myopathies includi...
...ardiac death, and use of ICDs in mitochondri...
...ents with mitochondrial myopathies includin...
...with mitochondrial myopathies including...
...ythm management and CIED implantati...
...able 6. Clinical scenarios for mana...
...enario A 30-year-old man with FA is referred...
Shared Decision-making and End-of-life Care
...cision-making and End-of-life Care...
...MDs, use of pacemakers and ICDs, s...
Shared decision-making and end-of-...
...ents with NMD who are considering or have a...
...ts with NMD in whom the presence of...
...patients with NMD who are considerin...
...n patients with NMD who have an ICD and are und...
...tients with NMD who have an ICD and are expe...
...patients with NMD who have a pacemaker or ICD an...
...Clinical scenarios for end-of-life mana...
...scenario 1 A 62-year-old woman with...
...cenario 2 A 39-year-old woman with Emer...
...inical scenario 3 A 17-year-old...
...ical scenario 4 A 46-year-old woman w...