Malignant Arrhythmias and Sudden Cardiac Death Flashcards
What is Noncompaction Cardiomyopathy (NCCM)?
A distinct primary genetic cardiomyopathy recognized by the AHA and classified as unclassified cardiomyopathy by the ESC.
What are the key complications associated with NCCM?
- Chronic heart failure
- Lethal arrhythmias
- Thromboembolic events
- Sudden cardiac death (SCD)
What is the reported mortality rate in adults with NCCM?
18%
What is the reported mortality rate in children with NCCM?
0–13%
How is Sudden Cardiac Death (SCD) defined?
Death from cardiac causes with an abrupt loss of consciousness less than 1 hour after onset of symptoms.
What percentage of sudden cardiac deaths are attributed to coronary artery disease?
65–70%
In NCCM patients, what are the primary causes of sudden cardiac death?
- Ventricular tachycardia (VT)
- Ventricular fibrillation (VF)
- Asystole
What is the most effective therapy to prevent sudden death in NCCM patients?
Implantable cardioverter defibrillator (ICD)
What is the incidence of NCCM in infants?
0.80 per 100,000 individuals per year
What is the incidence of NCCM in adults?
0.05%
What arrhythmias are commonly associated with NCCM?
- Bundle branch reentry
- Idiopathic VT
- Right ventricular outflow tract origin
- Left bundle branch and right bundle branch morphologies
- Bidirectional and fascicular VT
- Polymorphic VT and VF
What percentage of adults with NCCM experience ventricular arrhythmias?
38–47%
What are the proposed causes of arrhythmias in NCCM patients?
- Arrest in embryogenic development of the heart
- Disturbed compaction of the myocardium
- Inappropriate maturation of the cardiac conduction system
- Subendocardial ischemia
What is the significance of early repolarization (ER) in NCCM patients?
ER is associated with malignant ventricular arrhythmias and is found in a high percentage of NCCM patients.
What is the clinical presentation of NCCM?
- Chest pain
- Dyspnea
- Palpitations
- Edema
- Syncope
- Embolic ischemic stroke
- Myocardial infarction
- Sudden cardiac death
What are the major clinical manifestations of NCCM?
- Heart failure
- Supraventricular or ventricular arrhythmias
- Thrombo-embolic events
What is the relationship between ECG findings and NCCM?
Approximately 90% of NCCM patients have ECG abnormalities, but these findings are not specific.
What is the frequency of atrial fibrillation in adult NCCM patients?
5–29%
What is Wolff-Parkinson-White syndrome?
A preexcitation syndrome characterized by the presence of an accessory pathway that predisposes to arrhythmias.
What is the typical diagnostic approach for NCCM?
Careful history taking and physical examination, with attention to cardiac symptoms and family history.
What percentage of NCCM patients experience sudden cardiac death according to a large pediatric study?
6%
What is the significance of the diagnosis of NCCM in asymptomatic individuals?
The true prevalence may be higher as asymptomatic individuals may go unnoticed.
What was the outcome for the 35-year-old woman with NCCM mentioned in the case report?
She had an out-of-hospital cardiac arrest and was successfully resuscitated, later receiving an ICD.
What is a key challenge in epidemiological research of NCCM?
Lack of consensus on absolute diagnostic criteria.
