Sudden Adult Death Syndrome (SADS): Coronial Cardiology and Family Screening

Sudden adult death syndrome (SADS) represents a complex and sensitive area within medico-legal practice. When a previously healthy adult dies suddenly and unexpectedly, the coronial process often seeks to determine whether an inherited cardiac condition may have contributed. For solicitors acting in clinical negligence, personal injury, or inquest proceedings, understanding the interplay between coronial cardiology, family screening obligations, and the role of expert evidence is essential. This article outlines the clinical frameworks, legal considerations, and practical steps for instructing a consultant cardiologist expert witness in cases involving SADS.

Clinical Context: Sudden Adult Death Syndrome and Inherited Cardiac Conditions

Sudden adult death syndrome is defined as a sudden, unexplained death in an individual over the age of one, where post-mortem examination fails to identify a clear cause. In many cases, SADS is attributed to an underlying inherited cardiac condition, such as:

• Hypertrophic cardiomyopathy (HCM)
• Arrhythmogenic right ventricular cardiomyopathy (ARVC)
• Long QT syndrome (LQTS)
• Brugada syndrome
• Catecholaminergic polymorphic ventricular tachycardia (CPVT)
• Dilated cardiomyopathy (DCM)

These conditions often remain undiagnosed during life, either because symptoms are absent or because they are attributed to other causes, such as anxiety or vasovagal syncope. The first presentation may be a fatal arrhythmia, making post-mortem investigation and family screening critical for identifying at-risk relatives.

In medico-legal practice, expert opinion may address whether the deceased exhibited symptoms or signs that should have prompted earlier investigation. For example, a history of unexplained syncope, palpitations, or a family history of sudden death may raise questions about whether appropriate referrals to cardiology or cardiac genetics services were made. Current NICE guidance emphasises the importance of recognising red flags for inherited cardiac conditions, particularly in young adults presenting with syncope or arrhythmias.

Coronial Process and the Role of the Expert Witness

Under the Coroners and Justice Act 2009, a coroner must investigate deaths that are violent, unnatural, or of unknown cause. When SADS is suspected, the coroner may instruct a consultant cardiologist to provide an expert report addressing:

• The likely cause of death, based on post-mortem findings, clinical history, and family history
• Whether an inherited cardiac condition may have contributed
• The appropriateness of family screening recommendations
• Whether any alleged breaches of duty in the deceased’s clinical care may have contributed to the outcome

In cases where an inherited condition is suspected, the coroner may issue a Prevention of Future Deaths report under regulation 28 of the Coroners (Investigations) Regulations 2013. These reports highlight systemic issues, such as delays in diagnosis or failures to implement family screening programmes, and are addressed to organisations with the power to effect change. For solicitors, such reports can provide valuable evidence in clinical negligence claims, particularly where multiple deaths in a family suggest a pattern of missed opportunities for intervention.

The expert witness’s role in coronial proceedings is governed by CPR Part 35, which requires that reports are objective, unbiased, and address the specific questions posed by the coroner. The expert must also consider whether their opinion is consistent with the Bolam and Bolitho tests, particularly where allegations of clinical negligence are made. For example, if the deceased presented to primary or secondary care with symptoms suggestive of an inherited arrhythmia syndrome, the expert may be asked to assess whether the standard of care fell below what would be expected of a reasonably competent practitioner.

Family Screening: Legal and Clinical Obligations

One of the most contentious areas in SADS cases is the duty to screen surviving family members. When an inherited cardiac condition is identified or suspected, current clinical guidelines recommend cascade screening for first-degree relatives. This may include:

• Clinical assessment, including history and examination
• 12-lead electrocardiogram (ECG)
• Echocardiogram or cardiac MRI
• Genetic testing, where a pathogenic variant has been identified in the deceased

The legal duty to screen family members arises from the principle that healthcare providers owe a duty of care not only to the patient but also to their relatives, where harm is foreseeable. This was explored in the case of ABC v St George’s Healthcare NHS Trust and others [2020], where the Court of Appeal held that clinicians may owe a duty of care to disclose genetic information to at-risk relatives, even where the patient refuses consent. While this case concerned Huntington’s disease, the principles are applicable to inherited cardiac conditions, particularly where early intervention could prevent sudden death.

In medico-legal practice, expert witnesses may be asked to assess whether the duty to screen was fulfilled, and whether delays or omissions in screening contributed to harm. For example, if a relative of the deceased later dies suddenly and is found to have the same inherited condition, questions may arise about whether earlier screening could have prevented the second death. The expert’s report must address whether the standard of care met the requirements of Bolam and Bolitho, and whether any alleged breaches were causative of harm.

Common Pitfalls in Family Screening

Several issues frequently arise in SADS cases involving family screening:

• Delays in referral: Delays in referring relatives for screening, particularly where the deceased’s post-mortem identifies a likely inherited condition, are a common allegation. Expert witnesses may be asked to assess whether the delay fell below the standard of care and whether earlier intervention could have altered the outcome.
• Incomplete screening: Screening may be limited to an ECG without further imaging or genetic testing. While this may be appropriate in some cases, the expert must consider whether the screening provided was sufficient given the clinical context.
• Failure to act on results: Even where screening is performed, failure to act on abnormal results (e.g., not referring a relative with a prolonged QT interval for further assessment) may give rise to liability.
• Genetic testing limitations: Genetic testing may not always identify a pathogenic variant, even where an inherited condition is clinically suspected. The expert must clarify whether the absence of a genetic diagnosis excludes the possibility of an inherited condition, or whether clinical screening remains necessary.

Medico-Legal Challenges in SADS Cases

Cases involving SADS present unique challenges for solicitors and expert witnesses alike. Key issues include:

1. Causation and the Eggshell Skull Principle

In clinical negligence claims, establishing causation can be difficult where the deceased had an underlying, undiagnosed condition. The eggshell skull principle, as established in Smith v Leech Brain [1962], holds that a defendant must take their victim as they find them. However, where the harm is the result of a pre-existing condition, the claimant must demonstrate that the alleged breach of duty materially contributed to the outcome. In SADS cases, this may involve assessing whether earlier diagnosis or intervention could have prevented the fatal arrhythmia.

The case of Bailey v Ministry of Defence [2008] is also relevant, as it established that where a breach of duty contributes to an outcome, even if other factors are also at play, the defendant may be liable for the full extent of the harm. For example, if a delay in diagnosing an inherited condition contributed to the deceased’s death, the defendant may be liable even if the condition itself was the primary cause.

2. Limitation Issues

The Limitation Act 1980 imposes a three-year time limit for bringing clinical negligence claims, running from the date of knowledge of the injury. In SADS cases, this can be problematic where the deceased’s relatives only become aware of a potential claim years after the death, particularly if they were not informed of the coroner’s findings or the possibility of an inherited condition. Solicitors must carefully consider whether an application to disapply the limitation period under section 33 of the Act is appropriate.

3. Apportionment of Liability

In cases where multiple healthcare providers are involved (e.g., primary care, emergency medicine, and cardiology), apportionment of liability may be necessary. The expert witness may be asked to assess the relative contributions of each provider’s alleged breaches to the outcome. For example, if the deceased presented to primary care with syncope but was not referred, and later presented to the emergency department with the same symptoms but was discharged without investigation, the expert may need to determine which breach was more significant in contributing to the death.

4. Inquests and Article 2 ECHR

Where the state’s obligations under Article 2 of the European Convention on Human Rights (the right to life) are engaged, the coroner must conduct an enhanced investigation. This may arise where there are allegations of systemic failures, such as delays in implementing family screening programmes or failures to follow up abnormal test results. For solicitors, identifying whether Article 2 is engaged can be critical, as it may influence the scope of the inquest and the evidence required.

Instructing a Cardiology Expert Witness in SADS Cases

For solicitors acting in SADS cases, instructing a consultant cardiologist with expertise in inherited cardiac conditions and medico-legal practice is essential. Key considerations when selecting an expert include:

• Subspecialty expertise: The expert should have experience in inherited cardiac conditions, including the interpretation of genetic test results, imaging findings, and post-mortem reports. Subspecialty accreditation in cardiac genetics or electrophysiology may be advantageous.
• Medico-legal experience: The expert should be familiar with CPR Part 35 requirements, including the duty to provide an objective and unbiased report. Experience in preparing reports for coronial proceedings, clinical negligence claims, and inquests is essential.
• Understanding of legal tests: The expert must be able to apply the Bolam and Bolitho tests to the facts of the case, and to address questions of causation and apportionment. Familiarity with relevant case law, such as Montgomery v Lanarkshire Health Board [2015] and Khan v Meadows [2021], is also important.
• Communication skills: The expert must be able to explain complex clinical concepts in a manner that is accessible to solicitors, barristers, and the court. This includes the ability to prepare clear, concise reports and to give oral evidence effectively.

When instructing an expert, solicitors should provide:

• All relevant medical records, including primary and secondary care notes, emergency department attendances, and any previous cardiology investigations
• The post-mortem report and any specialist cardiac pathology findings
• Coronial documents, including the coroner’s report and any Prevention of Future Deaths reports
• Details of any family screening that has been performed, including genetic test results
• A clear letter of instruction, outlining the specific questions the expert is being asked to address

Practical Guidance for Solicitors

For solicitors acting in SADS cases, the following steps can help to build a robust claim or defence:

1. Early instruction of an expert: Given the complexity of inherited cardiac conditions, early instruction of a cardiology expert witness can help to identify key issues and guide the investigation. This is particularly important where limitation may be an issue.
2. Review of coronial documents: The coroner’s report and any Prevention of Future Deaths reports can provide valuable evidence of systemic issues or missed opportunities for intervention. These documents should be reviewed carefully, as they may highlight areas for further investigation.
3. Assessment of family screening: If family screening was performed, the expert should review whether it was appropriate and timely. If screening was not performed, the expert should assess whether there was a duty to screen and whether any alleged breach contributed to harm.
4. Consideration of genetic testing: Where genetic testing has been performed, the expert should review the results and consider whether further testing or counselling was indicated. The absence of a genetic diagnosis does not necessarily exclude an inherited condition, and the expert should clarify whether clinical screening remains necessary.
5. Engagement with Article 2 ECHR: Where systemic failures are alleged, solicitors should consider whether Article 2 is engaged. This may influence the scope of the inquest and the evidence required to establish a breach of duty.
6. Preparation for joint statements: In cases where both parties instruct experts, the preparation of a joint statement under CPR Part 35.12 can help to narrow the issues in dispute. Solicitors should ensure that their expert is prepared to engage constructively in this process.

Conclusion

Sudden adult death syndrome presents unique challenges in medico-legal practice, particularly where inherited cardiac conditions are suspected. For solicitors, understanding the coronial process, the duty of family screening, and the role of expert evidence is essential for navigating these complex cases. Early instruction of a consultant cardiologist expert witness, with subspecialty expertise in inherited cardiac conditions, can provide clarity on the clinical and legal issues at stake. By adopting a structured approach to instruction and evidence gathering, solicitors can ensure that their clients’ cases are built on a robust foundation of expert opinion.

Specialist cardiology medico-legal assessment from an experienced consultant cardiologist expert witness can be pivotal in cases of this nature, particularly where questions of breach of duty, causation, or the appropriateness of family screening arise.