What should be listed as the cause of death in a patient with suspected ventricular arrhythmia (VA)?

Documenting Cause of Death in Suspected Ventricular Arrhythmia

When ventricular arrhythmia is suspected as the cause of death, document it as "sudden cardiac death" (SCD) or "sudden arrhythmic death" with specification of the underlying cardiac substrate if identified, or as "sudden arrhythmic death syndrome" (SADS) if the heart is structurally normal at autopsy. 1

Primary Documentation Framework

The cause of death should be documented based on the autopsy findings and clinical circumstances:

• If structural heart disease is identified at autopsy: Document as "sudden cardiac death due to [specific cardiac disease]" with ventricular arrhythmia as the mechanism 1, 2
• If the heart is structurally normal: Document as "sudden arrhythmic death syndrome" (SADS), which represents sudden death with a normal heart at postmortem examination 3
• Time-based definition: SCD is defined as death from unexpected circulatory arrest, usually due to cardiac arrhythmia, occurring within 1 hour of onset of symptoms 1

Essential Autopsy Requirements

A properly conducted autopsy must address five critical questions to accurately document the cause of death 1:

• Cardiac attribution: Whether death is attributable to cardiac disease
• Disease identification: The nature of any cardiac disease present
• Mechanism determination: Whether the mechanism of death was arrhythmic versus non-arrhythmic (e.g., aortic rupture)
• Hereditary assessment: Evidence of inheritable cardiac disease requiring family screening
• Toxicology exclusion: Possibility of toxic substances, illicit drugs, or other unnatural causes 1, 2

Mandatory Autopsy Components

Standard histological examination of the heart is required and should include mapped, labeled blocks of myocardium from representative transverse slices of both ventricles 1. This is critical because:

• Myocardial scarring, fibrosis, or fibrofatty replacement may indicate the arrhythmic substrate 4, 5
• Microscopic findings may reveal cardiomyopathy not apparent on gross examination 1
• Histology can identify inflammatory processes or infiltrative diseases 1

Analysis of blood and body fluids for toxicology and molecular pathology is recommended in all victims of unexplained sudden death 1. This helps exclude:

• Drug-induced arrhythmias (QT-prolonging medications, sodium channel blockers) 1
• Electrolyte disturbances (hypokalemia, hyperkalemia) 1
• Substance abuse or withdrawal states 2

Specific Documentation by Clinical Scenario

Witnessed Cardiac Arrest with Documented VF/VT

• Document as "sudden cardiac death due to ventricular fibrillation" or "ventricular tachycardia" 1, 6
• Note that VF is the first recorded arrhythmia in 75% of sudden cardiovascular collapse cases 6
• Specify the underlying substrate (e.g., "in the setting of coronary artery disease with prior myocardial infarction") 1

Unwitnessed Death with Suspected Arrhythmia

• Document as "sudden cardiac death, presumed arrhythmic" when circumstances suggest arrhythmic mechanism 1, 3
• Note that 82% of SADS deaths occur during sleep or at rest, while 16% occur with exercise or emotional stress 3
• In young patients (<18 years) or males, exercise-related death is more common and should be documented 3

Structurally Normal Heart (SADS)

• Document as "sudden arrhythmic death syndrome" when autopsy reveals no structural abnormalities 1, 3
• This represents 2-54% of sudden deaths depending on autopsy protocol thoroughness 1
• Targeted post-mortem genetic analysis should be considered for suspected channelopathies (long QT syndrome, Brugada syndrome, catecholaminergic polymorphic VT) or cardiomyopathies 1

Critical Pitfalls to Avoid

Do not use vague terminology such as "cardiac arrest" or "cardiopulmonary arrest" as the primary cause of death—these describe the terminal event, not the underlying cause 1. Instead:

• Specify "sudden cardiac death due to ventricular arrhythmia" with the substrate identified 1
• Distinguish arrhythmic from non-arrhythmic cardiac death, as sudden death is not necessarily arrhythmic 6

Do not assume all sudden deaths are arrhythmic without proper investigation 6. Non-arrhythmic causes include:

• Aortic dissection or rupture 1
• Massive pulmonary embolism 1
• Cardiac rupture or tamponade 1

Do not overlook the need for family screening documentation 1. When documenting the cause of death, note if:

• The condition may be inherited (channelopathies, cardiomyopathies, familial coronary disease) 1
• First-degree relatives require clinical screening and genetic counseling 7
• Molecular autopsy identified a disease-causing mutation 1

Supporting Clinical Information to Document

Include available clinical history that supports the arrhythmic mechanism 3:

• Prior symptoms: Syncope (4.1% of SADS cases), documented arrhythmia (3.4%), palpitations 3
• Family history: Sudden death in relatives (4.2% of cases) 3
• Circumstances: Exercise-related, sleep-related, or stress-related death 3
• Medications: QT-prolonging drugs, antiarrhythmics, or other pro-arrhythmic agents 1
• Misdiagnosed conditions: History of "epilepsy" (present in 6.6% of SADS cases) may actually represent arrhythmic syncope 3

Specific Disease Documentation

When specific substrates are identified, document accordingly:

• Coronary artery disease: "Sudden cardiac death due to ventricular arrhythmia in the setting of coronary atherosclerosis with [specify findings]" 1, 4
• Cardiomyopathy: Specify type (dilated, hypertrophic, arrhythmogenic right ventricular) with arrhythmic mechanism 7, 5
• Channelopathy (if suspected): "Sudden arrhythmic death syndrome, suspected [specific channelopathy] pending genetic testing" 1

Note that up to 90% of SADS victims have no preceding symptoms or recognized risk factors, making autopsy and genetic investigation essential for accurate documentation and family counseling 3.