Evaluation and Management of Arrhythmic Risk in Neuromuscular Disorders

Publication Date: April 27, 2022

Overview

Overview

Top 10 Take-Home Messages

  1. 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.
  2. 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.
  3. 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.
  4. 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.
  5. 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.
  6. 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.
  7. 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.
  8. 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.
  9. 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.
  10. 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

...eral Principles for Arrhythmic Risk in...

...ble 1. Genetics, cardiovascular compli...


Duchenne, Becker, and Recessive Limb-girdle Muscular Dystrophies

...cker, and Recessive Limb-girdle Muscular Dyst...

...le 2. Recessive forms (type 2) of LGMDs...


...ing and risk stratification in Duchenne,...

...oordinated care of patients with D...

...patients with DMD, BMD, or LGMD2, guideline-d...

...th DMD, BMD, or LGMD2, cardiac evaluation...

...es who are carriers of a pathogenic...

...ients with DMD, BMD, or LGMD2 who have symptoms of...


...as, conduction disorders, and use of pacing...

In patients with DMD, BMD, or LGMD2, with do...

...s with DMD, BMD, or LGMD2 and third-d...

...atients with DMD, BMD, or LGMD2 with an L...


...ythmias in Duchenne, Becker, and rec...

...th DMD, BMD, or LGMD2, anticoagulation accordin...


...As, sudden cardiac death, and use of ICDs in...

...patients with DMD, BMD, or LGMD2 with spontaneous...

...with DMD, BMD, or LGMD2 with an LVEF ≤35% d...


...Rhythm management and CIED in patients with DMD,...


...inical scenarios for the management of arrhythmia...

...Clinical sce...

...ario 2 A 31-year-old man with BMD is f...

...Clinical s...


Myotonic Dystrophy Types 1 and 2

Myotonic Dystrophy Typ...

...ng and risk stratification in DM1 and DM2...

...dinated care of patients with DM1 or DM2...

...th DM1 or DM2, cardiac evaluation inclu...

...ith DM1 or DM2 and cardiac conduction disorder, cl...

...s with DM1 or DM2 with symptoms con...

...DM1 or DM2 with symptoms suggestiv...


...ardias, conduction disorders, and use of paci...

...ith DM1 or DM2 with an LVEF ≤35%, sinus rh...

...tients with DM1 or DM2 and documente...

...s with DM1 or DM2 and third-degree or advanced se...

...th DM1 or DM2 and marked first-degr...

...patients with DM1 or DM2 with HV interv...


...l arrhythmias in DM1 and...

...patients with DM1 or DM2, anticoagulation acc...


...dden cardiac death, and use of ICDs in DM1 and DM2...

...with DM1 or DM2 in whom ICD therapy is plan...

...n patients with DM1 or DM2, who are survivors of...

...ith DM1 or DM2 and an LVEF ≤35%,...

...with DM1 or DM2 in whom clinically rele...

...ith DM1 or DM2 in whom PPM implantation is...


...2. Rhythm management and CIED implantation...


...cal scenarios for the management of a...

...different degrees of muscle impair...

...M1...

...rio 1 A 63-year-old man with D...

...rio 2 A 52-year-old man with DM1 and...

...MD

Clinical scenario 3 A 72-year-old...

...scenario 4 A 68-year-old woman with DM1...


Emery-Dreifuss and Limb-girdle Type 1B Muscular Dystrophy

...reifuss and Limb-girdle Type 1B Muscul...

...sting and risk stratification in EDMD a...

...e of patients with EDMD or LGMD1B should be condu...

...patients with EDMD or LGMD1B, cardiac eval...

...relatives of patients with genetically confi...

...th EDMD or LGMD1B, who have symptoms...

...with EDMD or LGMD1B with symptoms cons...


...s, conduction disorders, and use of...

...atients with EDMD or LGMD1B with an LVEF...

In patients with EDMD or LGMD1B in whom pacing is...


...arrhythmias in EDMD and LGMD1B...

...ents with EDMD or LGMD1B, anticoagul...

...with EDMD, anticoagulation is recommen...


...iac death, and use of ICDs in EDMD...

...tients with EDMD or LGMD1B in whom ICD ther...

...ents with EDMD or LGMD1B who are s...

In patients with EDMD or LGMD1B with...

...with EDMD or LGMD1B with an LVEF ≤3...

...with EDMD or LGMD1B in whom clinicall...

...ts with EDMD or LGMD1B with LVEF...

...ts with EDMD or LGMD1B with at least o...

...ients with EDMD or LGMD1B with symptomat...


...gure 3. Rhythm management and CIED implan...


...5. Clinical scenarios for the management of...

...DMD

...nario 1 A 25-year-old man prese...

...al scenario 2 A 64-year-old man with EDM...

...inical scenario 3 A 12-year-old boy wit...

...GMD1B

...scenario 4 A 42-year-old woman...

...linical scenario 5 A 35-year-old man wi...


Facioscapulohumeral Muscular Dystrophy

...scapulohumeral Muscular Dystroph...

Diagnostic testing and risk stratification...

...h FSHD, cardiac evaluation including examin...


Mitochondrial Myopathies Including Friedreich Ataxia

...opathies Including Friedreich Ataxia...

...stic testing and risk stratification in mito...

...re of patients with mitochondrial myopathies i...

...tients with mitochondrial myopathies including...


...nduction disorders, and use of pacing or CRT in...

...patients with mitochondrial myopathie...

...patients with mitochondrial myopathies includ...

...with FA with an LVEF ≤35% despit...

...s with mitochondrial myopathies includi...


...rhythmias in mitochondrial myopathies including...

...atients with mitochondrial myopath...


...sudden cardiac death, and use of IC...

...patients with mitochondrial myopathie...

...h mitochondrial myopathies including FA with an L...


...hythm management and CIED implantation...


.... Clinical scenarios for management of patient...

...l scenario A 30-year-old man with FA...


Shared Decision-making and End-of-life Care

Shared Decision-making and End-of-life...

...NMDs, use of pacemakers and ICDs, shared decision...


...d decision-making and end-of-life decisions...

...with NMD who are considering or have a...

...atients with NMD in whom the presence of...

...nts with NMD who are considering ICD re...

...th NMD who have an ICD and are undertaking advanc...

...with NMD who have an ICD and are expe...

...with NMD who have a pacemaker or ICD...


...e 8. Clinical scenarios for end-of-life manag...

...nario 1 A 62-year-old woman with DM1, n...

...nical scenario 2 A 39-year-old woman with E...

...cenario 3 A 17-year-old adoles...

...cenario 4 A 46-year-old woman with DM1 an...