Sudden Cardiac Death in Children Affected by Cardiomyopathies: An Update on Risk Factors and Indications at Transvenous or Subcutaneous Implantable Defibrillators

Abstract

In the present paper, we will discuss the main cardiomyopathies affecting children with a specific focus on risk stratification and prevention of sudden cardiac death (SCD). We will discuss the main clinical features of hypertrophic cardiomyopathy (HCM), dilated and restrictive cardiomyopathies, left ventricular non-compaction (LVNC) and arrhythmogenic cardiomyopathy (AC), always highlighting their peculiarities in the pediatric age. Since sudden cardiac death may be the first manifestation of the disease, even in children, the identification of the specific underlying condition and of risk factors are pivotal to carry out the appropriate preventing strategies. ICD recommendations in children are similar to adults, but supporting evidences are not so solid, being based on registries or single center studies. Furthermore, children and young patients are most likely to manifest long term complications related to an implanted ICD, and this should be taken into account when evaluating the risk benefit ratio. In this perspective, subcutaneous ICDs (S-ICDs) could carry an advantage; however, they cannot be considered in small children for technical reasons. Data on effectiveness and safety of S-ICDs in a pediatric population is still lacking, although some limited experiences are reported and will be discussed in the current review.

Aborted Sudden Death Due to Severe Ventricular Arrhythmia in Timothy Syndrome

“…23,24 Thus, in small body patients, NT-ICDs are often the only option. [22][23][24][25] It is possible to use either an abdominal device and subcutaneous shock coil, or a subcardiac device and a pleural shock coil. 25 Clinical evidence shows that infectious diseases are the second leading cause of death in TS.…”

“…[22][23][24][25] It is possible to use either an abdominal device and subcutaneous shock coil, or a subcardiac device and a pleural shock coil. 25 Clinical evidence shows that infectious diseases are the second leading cause of death in TS. 11 In the present case report, the patient presented a reversed CRA, and later developed septic lung disease, culminating in death.…”

Cadherin 2-Related Arrhythmogenic Cardiomyopathy

“…Another issue to be considered is that if the concept that the CDH2-associated ACM has a predominantly arrhythmogenic profile will be validated-similar to other genetic forms of ACM, such as those linked to lamin A (LMNA), filamin C (FLNC), and phospholamban (PLN) 4 specific recommendations for internal cardioverterdefibrillator implantation might ensue. 25 Clearly, all these observations are based on a limited number of patients. Further research and wider ascertainment strategies should provide more robust data for accurate genetic counseling of patients with CDH2 variants.…”

ICD Outcome in Pediatric Cardiomyopathies

“…ICD may prevent SCD from malignant ventricular arrhythmias in children with cardiomyopathies [5][6][7], increasing the number of ICDs implanted for primary prevention [8]. However, in this specific cohort, several factors may affect the use of ICD, causing complications related mainly to physiologic parameters in children (body dimensions, progressive growth both in height and weight, complex anatomy, physical activity) and devices (size, lead characteristics, implantation approach and procedure) [9].…”