Statement of Principles concerning sick sinus syndrome (Reasonable Hypothesis) (No. 66 of 2022)

The SOP turns on a small set of core concepts that determine its operation: the definition of sick sinus syndrome; the “reasonable hypothesis” evidentiary threshold; the lists of specified factors and their temporal limits; the requirement of a relationship to relevant service; and the cross‑reference to other SOPs.

Meaning of sick sinus syndrome. The instrument defines SSS as a group of cardiac arrhythmias caused by sinus node dysfunction producing atrial rates inappropriate for physiological requirements, with accompanying clinical symptoms (s7(2)(a)-(b)). The SOP excludes congenital SSS (s7(2)(b)). The notes to s7(2) state common manifestations (bradycardia, pauses, bradycardia-tachycardia syndrome) and typical symptoms (fatigue, presyncope, syncope, dyspnoea on exertion, chest discomfort); the notes also record that documented sinus node dysfunction correlates with symptoms and that symptoms are frequently intermittent and progressively worse (s7(2) Notes 1-2). The SOP expressly ties, but does not substitute, the ICD‑10‑AM code I49.5 to its meaning, emphasising that the textual definition controls application (s7(3)-(4)).

Reasonable hypothesis threshold. The SOP repeatedly frames its test as whether “a reasonable hypothesis has been raised” connecting SSS or death from SSS with relevant service (title; s9 introductory text). Section 9 then states that at least one of the enumerated factors must exist “as a minimum” before a reasonable hypothesis can be said to have been raised. This establishes a threshold that is applied by decision‑makers in the VEA/MRCA claim contexts specified in s5. The instrument does not define “reasonable hypothesis”; the phrase functions as the operative standard within which the listed factors are the determinative inputs.

Lists of factors and temporal windows. Section 9 separates factors relevant to clinical onset (s9(1)-(25)) from those relevant to clinical worsening (s9(26)-(50)). The factors encompass comorbid cardiac conditions (atrial fibrillation/flutter, hypertension, ischaemic heart disease, heart failure), prior inflammatory or infiltrative myocardial disease (viral, non‑viral myocarditis, non‑infectious myocarditis, infiltrative diseases), structural causes (neoplasm involving the sinoatrial node, non‑neoplastic compression), procedures and interventions (thoracic or invasive cardiac procedures within 1 year, anaesthesia within 30 days, heart transplant, cardiac stereotactic ablative radiotherapy or cryotherapy within 6 months), trauma (penetrating cardiac trauma within 3 months), drug exposure (a specified list within 30 days), extreme exertion (strenuous activity >6 METs average 20 hours/week for at least 5 continuous years, with the 5‑year cessation rule), and specific toxic insults (Viperidae envenomation within 48 hours). The Schedule supplies key definitions and the specified lists (Schedule 1).

Relationship to relevant service and inter‑SOP interaction. Section 10 requires that any factor used to raise a reasonable hypothesis must be related to relevant service. The SOP defines the categories of relevant service in the Schedule (operational, peacekeeping, hazardous, British nuclear test defence under the VEA; warlike and non‑warlike under the MRCA). Section 10(2) narrows the application of the clinical worsening factors (s9(26)-(50)) to cases where SSS pre‑existed the relevant service or was suffered or contracted before or during service but did not arise out of it; those factors therefore operate as material contribution or aggravation inputs rather than primary causal factors in such circumstances. Section 11 prescribes that if a listed factor references an injury/disease already covered by another SOP, the other SOP applies as in force.

Death and terminal event. The SOP includes death from SSS, defined to include deaths from terminal events or conditions contributed to by SSS, with “terminal event” given a non‑exhaustive list (pneumonia, respiratory failure, cardiac arrest, circulatory failure, cessation of brain function) in the Schedule (s7(5); Schedule 1).

Practical implication: the SOP is an enumerative, time‑sensitive evidentiary matrix that prescribes when the statutory threshold of a “reasonable hypothesis” is met for SSS and related death claims arising from defined kinds of relevant service. The Schedule contains the definitional building blocks (MET, obstructive sleep apnoea, specified lists of drugs, infiltrative diseases, mineral/electrolyte abnormalities, autoimmune diseases and thyroid conditions, MRCA and VEA definitions, and terminal event).

Primary affected parties. The instrument is directed at persons who make claims under the VEA s120A or MRCA s338, because it “applies to a claim to which section 120A of the VEA or section 338 of the MRCA applies” (s5). Those claimants therefore include veterans, former members of the Forces, and members of Peacekeeping Forces who assert that SSS or death from SSS is related to their relevant service. The Schedule defines “relevant service” as operational, peacekeeping, hazardous, British nuclear test defence services under the VEA and warlike or non‑warlike service under the MRCA (Schedule 1).

Decision‑makers and agencies. The Repatriation Medical Authority makes the SOP and records the medical‑scientific basis (s3, s8). Although this instrument does not itself set out the decision‑making process, it is intended to be applied by decision‑makers within the VEA and MRCA frameworks when assessing claims that fall under the cited sections (s5). Those decision‑makers will be required to determine whether, on the SOP’s terms, a reasonable hypothesis has been raised, based on evidence tendered by the claimant and official medical records. The instrument also interacts with other SOPs; if a factor refers to an injury or disease covered by another SOP, that other SOP applies in accordance with its terms (s11). That means administratively, practitioners who advise claimants and those adjudicating claims must check cross‑references to other SOP instruments.

Medical practitioners and record holders. The lists of factors create direct evidentiary tasks for treating clinicians and hospitals: clinical documentation of atrial arrhythmias, hypertension, ischaemic heart disease, heart failure, myocarditis (viral or non‑infectious), pericarditis, cardiomyopathy, infiltrative disease, neoplasm or compressive lesions, procedural and surgical records (with dates), medication histories (including drugs listed in the Schedule and the dates of use), sleep study reports for obstructive sleep apnoea, electrolyte and mineral results, and records showing heart transplant or anaesthesia dates. The SOP’s timing windows (e.g. anaesthesia within 30 days, procedures within 1 year, envenomation within 48 hours) mean clinical and pre‑hospital records are likely to be central evidence.

Legal and allied advisers. Practising lawyers, advocates, and representatives preparing claims for affected persons must collect and frame medical and ancillary evidence to show a listed factor existed at the relevant time and that it is related to relevant service (s10(1)). For clinical worsening claims that rely on s9(26)-(50), advisers must also show that the person’s SSS pre‑existed the relevant service or was suffered/contracted before or during but did not arise out of it (s10(2)).

Third parties and insurers. The instrument does not itself alter private contractual rights or insurance arrangements, but it may affect determinations that other bodies take into account when assessing liability or benefits. Because the SOP identifies particular clinical and temporal connections that raise a reasonable hypothesis for service‑relatedness, other agencies that look to VEA/MRCA determinations may see corresponding changes in the number and character of accepted claims.

Concentrated versus diffuse effects. The benefits of the SOP (a clear enumerated list that can be relied upon in claims) are concentrated on claimants who can marshal the particular evidence listed and on medical practitioners who document those conditions. The evidentiary and administrative burdens are dispersed across claimants generally: retrospective proof of drug exposure, procedure timing, sleep studies, biochemical results, or sustained physical activity at the MET thresholds may be resource‑intensive to assemble.

What the SOP imposes and what it enables are narrowly expressed in the instrument’s text. The SOP itself does not create new civil or criminal duties; instead, it defines an evidentiary framework and the threshold capable of raising a reasonable hypothesis connecting SSS (or death from SSS) with relevant service. Key duties and rights therefore flow from how the SOP is applied within the VEA and MRCA claims processes and the requirements it sets for claimants and decision‑makers.

Claimant obligations and rights. Claimants seeking to rely on this SOP must show that at least one of the factors listed in s9 existed at the relevant time (for clinical onset: s9(1)-(25); for clinical worsening: s9(26)-(50)). The SOP states that “at least one of the following factors must as a minimum exist before it can be said that a reasonable hypothesis has been raised connecting” SSS or death from SSS with relevant service (s9). For the factor to be operative it must be “related to the relevant service rendered by the person” (s10(1)). For clinical worsening factors in s9(26)-(50), the SOP limits application to circumstances of material contribution or aggravation where SSS was suffered or contracted before or during but did not arise out of relevant service (s10(2)); claimants must therefore be prepared to demonstrate temporal sequencing and whether the condition pre‑existed service.

Right to rely on cross‑referenced SOPs. If a listed factor in s9 refers to an injury or disease that is the subject of another SOP made under s196B(2) of the VEA, then “the factors in that Statement of Principles apply in accordance with the terms of that Statement of Principles as in force from time to time” (s11). This gives claimants and their advisers the right to rely on the terms of those other SOPs where relevant; but it also means that duties to apply the other SOPs may alter the evidence required or the outcome.

Decision‑maker duties. The instrument is made by the Repatriation Medical Authority (s3). The SOP imposes an obligation on the decision‑maker in a VEA/MRCA claim to treat the listed factors as the determinative list for raising a reasonable hypothesis when considering claims covered by s120A VEA or s338 MRCA (s5). The SOP does not itself set out decision‑making mechanics, but it requires decision‑makers to assess whether the evidence establishes one or more of the factors and that that factor is related to relevant service (s9; s10(1)). If a factor is one that another SOP covers, the decision‑maker must apply the other SOP’s terms (s11).

Evidence and proof duties. The SOP implies certain evidentiary duties: proof that a factor existed at the stated time (documented atrial fibrillation/flutter, clinical diagnosis of myocarditis, procedural dates, drug use within 30 days, laboratory values showing electrolyte abnormality, a sleep study for OSA, etc.). The Schedule makes clear what counts as the specified lists and definitions (Schedule 1). The SOP also notes that documented sinus node dysfunction correlates with symptoms (s7(2) Note 2), signalling that objective cardiological evidence will be material.

No autonomous right to compensation or penalty. The SOP does not itself create entitlements or penalties; it is an evidentiary instrument to be used in adjudicating claims under the VEA and MRCA (s5). Any duties to pay or to impose penalty flows from those statutes and the administrative determinations that follow application of this SOP, not from the SOP alone.

Duty to consider temporal limits and scope. The SOP places duties on parties to address the temporal windows it prescribes (for example, s9(18): thoracic or invasive cardiac procedures within 1 year; s9(20): surgical procedure with general/regional anaesthesia within 30 days; s9(21): cardiac stereotactic ablative radiotherapy/cryotherapy within 6 months; s9(22): penetrating cardiac trauma within 3 months; s9(23) and s9(48): drug exposure within 30 days; s9(25) and s9(49): Viperidae envenomation within 48 hours). Parties must therefore present evidence specifically tied to these timing constraints.

The SOP itself does not create criminal penalties or civil fines, nor does it prescribe enforcement mechanisms internal to the instrument. Its enforcement role is procedural and evidentiary within the VEA and MRCA claims systems. The instrument is designed to be applied by the relevant decision‑makers when determining whether a reasonable hypothesis has been raised linking SSS (or death from SSS) to relevant service for the claims identified in s5.

No statutory penalties in the SOP. Nowhere in the text does the instrument prescribe sanctions, penalties, fines, or enforcement processes against individuals for non‑compliance with its terms. Its operative content is definitional and prescriptive in the sense of listing medical and temporal factors; it does not, for example, create criminal liability for failure to provide information, nor does it set administrative penalties.

Administrative enforcement via claim outcomes. The practical enforcement effect of the SOP will be realised in claim determinations under the VEA s120A and MRCA s338 frameworks. The SOP sets the criteria that, if met by the evidence, will raise a reasonable hypothesis. That evidentiary conclusion will then be used by the agency deciding the claim to accept or reject assertions of service connection in accordance with the governing statute and administrative rules. Because those decision processes are external to the SOP text, the SOP does not itself describe appeal rights, review mechanisms, or sanctions for false statements. Any consequences for adverse findings, fraudulent claims, or failures to disclose will derive from the VEA/MRCA and associated administrative and criminal laws, none of which are reproduced in this instrument.

Investigation and evidentiary processes. While the SOP does not specify investigative powers, the enumerated factors create a de facto investigative and evidentiary regime. Decision‑makers will require contemporaneous clinical records, procedural notes, laboratory data, medication histories, imaging and pathology reports, operative records, sleep studies, and similar documentary evidence to establish whether a factor in s9 existed at the relevant time. The SOP increases the importance of timely documentation and record retention for both claimants and providers.

Discretion and interpretive enforcement risk. Because the SOP frames the threshold as a “reasonable hypothesis” and uses medical categories with clinical judgment attached (e.g. whether myocarditis is “viral” or “non‑infectious”; whether physical activity exceeded 6 METs averaged over 20 hours a week for 5 continuous years), decision‑makers will exercise medical and administrative judgement in applying the SOP. The instrument provides the medical matrix; it leaves interpretive enforcement,application to the facts,to decision‑makers within the VEA/MRCA regime.

Cross‑SOP enforcement. Section 11 requires the application of other SOPs where a factor refers to an injury/disease that another SOP covers. This creates an enforcement interaction: where such cross‑references exist, the decision‑maker must apply the other SOP’s factors “as in force from time to time” (s11). This can affect which evidentiary standards and temporal constraints apply in any specific claim.

The SOP is expressly made under subsection 196B(2) of the VEA (s3) and applies to claims to which s120A of the VEA or s338 of the MRCA applies (s5). It therefore functions as a statutory instrument within the broader VEA/MRCA framework and interacts with other SOPs and with the administrative processes of those Acts.

Direct statutory interaction. The instrument's authority (s3) and application (s5) tie it directly to the VEA and MRCA. It does not, however, restate or alter substantive provisions of those Acts; it supplies medical‑scientific guidance about when a reasonable hypothesis of service connection is raised for SSS or death from SSS. Any rights and obligations to payment or rehabilitation remain governed by the VEA or MRCA, with this SOP operating as an input to those statutory determinations.

Cross‑SOP interplay. Section 11 provides that if a factor in this SOP refers to an injury or disease that another SOP addresses, then “the factors in that Statement of Principles apply in accordance with the terms of that Statement of Principles as in force from time to time” (s11). Practically, this creates three interactions:

• Where a listed factor is itself a condition covered by a different SOP, decision‑makers must consult that SOP for the applicable factors, timeframes and evidentiary rules.
• Such cross‑referencing can shift the evidentiary burden or apply additional temporal or causal tests contained in the other SOP.
• An up‑to‑date approach is mandated because s11 requires application of the other SOP “as in force from time to time,” meaning amendments to other SOPs will influence applications of factors referenced here.

This cross‑SOP mechanism centralises medical determinative criteria in SOP instruments while requiring co‑ordination among them. Advisers must therefore map factor references to the current operational SOPs.

Administrative procedures and evidence law. The SOP will be used within the VEA/MRCA decision frameworks. It does not specify evidentiary rules of proof (for example whether medical opinion must be from a specialist), nor does it alter disputable standards of causation within the governing Acts beyond supplying the “reasonable hypothesis” threshold and the list of factors that raise it (s9). How decision‑makers treat competing medical opinions, the admissibility of records, and the procedural rules for review and appeal remain governed by the VEA, the MRCA, and associated administrative law, not this SOP.

No alteration of private law liabilities. The SOP does not amend contracts, tort law, or private insurance law. It may, however, influence determinations that other bodies take into account when assessing liability or benefits if those agencies adopt or reference the RMA’s SOPs. The instrument itself contains no express provision that binds third parties outside the statutory claims processes it governs.

International law, health regulation, criminal law. The SOP does not engage international treaties, health regulation regimes, criminal penalties, or external licensing conditions directly. Any interface,for example, where a criminal assault causing penetrating cardiac trauma is alleged,will be managed via the usual criminal and civil systems; the SOP will only be relevant to the question of whether that specific injury or event is a factor raising a reasonable hypothesis of service relation for SSS claims.

This instrument replaces a prior SOP on the same clinical subject and records its creation date and commencement date. It is concise in amendment terms but provides the key transactional steps and identifiers.

Creation and commencement. The instrument is dated 24 June 2022 and “commences on 25 July 2022” (s2). The instrument is numbered No. 66 of 2022 in the Repatriation Medical Authority’s Statements of Principles catalogue (title). The Common Seal of the Repatriation Medical Authority was affixed “at the direction of Professor Terence Campbell AM, Chairperson” as recorded at the head of the instrument.

Repeal of prior SOP. Section 4 expressly repeals “The Statement of Principles concerning sick sinus syndrome No. 15 of 2014 (Federal Register of Legislation No. F2014L00020) made under subsection 196B(2) of the VEA.” The repeal is unconditional in the instrument and thus replaces the earlier SOP as the operative RMA statement on SSS from the commencement date. The instrument therefore represents an update or replacement rather than an amendment to the 2014 instrument.

Authority for change. Section 3 records that the instrument is “made under subsection 196B(2) of the Veterans' Entitlements Act 1986.” That citation supplies the statutory power under which the RMA may determine and amend SOPs. Although the instrument does not reproduce subsection 196B(2) itself, the entry asserts the statutory parentage.

No further amendments recorded. The instrument contains no schedule of amendments or transitional provisions beyond the repeal in s4 and the commencement date in s2. There is no express saving clause for determinations made under the repealed 2014 SOP; practitioners must therefore conclude that, from 25 July 2022, this instrument supersedes the prior SOP for the purposes of claims to which s120A VEA or s338 MRCA applies.

Operational implication. Because s11 requires application of other SOPs “as in force from time to time,” decision‑makers and practitioners must monitor any further SOPs or amendments that may be published after this instrument’s commencement. The instrument’s repeal of the 2014 SOP and its own status as No. 66 of 2022 mark it as the controlling RMA instrument for SSS matters from its commencement date.

Record and provenance. The instrument records its Federal Register reference indirectly via the repeal reference to the earlier SOP’s Federal Register number. The inclusion of the RMA Chairperson’s name and the affixed common seal shows the formal execution. There is no explanatory memorandum or second reading speech included in the text provided; the instrument’s own s8 supplies the RMA’s statement that there is “sound medical‑scientific evidence” supporting the connections described.

The instrument itself does not record any litigation history. It is a statement of medical principles and does not list cases, appeals, judicial reviews, or tribunal decisions. Therefore, within the text provided, there are no named court judgments, administrative appeals, or litigation outcomes anchored to this SOP.

Implications of absent litigation history in the instrument. Because the SOP is an administrative medical instrument and not a court decision, the absence of litigation history in the text is to be expected. The instrument prescribes how decision‑makers should treat certain medical facts when assessing claims under the VEA and MRCA. Any disputes arising from its application,such as disagreements about whether a listed factor existed at the relevant time, whether that factor is related to relevant service, or whether a “reasonable hypothesis” has been raised,would be litigated or reviewed under the appeal and review mechanisms available under the VEA/MRCA and administrative law, not within the SOP itself. The instrument does not specify or limit appeal routes or judicial review.

Potential grounds for dispute in practice. Although the instrument contains no litigation record, its content suggests predictable areas for contest in claims and potential judicial review:

• Interpretation of “reasonable hypothesis” and whether the existence of one of the factors is sufficient in particular fact patterns.
• Medical classification disputes (e.g. whether myocarditis is “viral” or “non‑infectious,” or whether an infiltrative disease on the specified list is present).
• Temporal disputes about whether a factor existed within the time windows set (e.g. anaesthesia within 30 days, procedure within 1 year, envenomation within 48 hours).
• The application of s9(26)-(50) for material contribution or aggravation where SSS pre‑existed or was suffered/contracted before or during service but did not arise out of it (s10(2)), which introduces factual complexity about whether SSS “arose out of” service.
• Cross‑SOP application issues where s11 requires resort to other SOPs “as in force from time to time.”

Because the text provides no litigation examples, practitioners and decision‑makers must anticipate disputes and prepare evidence accordingly. The SOP’s structure makes predictable the factual and medical contestation points that would be brought to administrative review or judicial appeal, even though no litigation history is recorded in the instrument text.

This SOP contains many specifics where errors, misunderstandings, or evidentiary failures can materially affect outcomes. Below are concrete “gotchas” grounded in the text, focusing on timing windows, definitional traps, cross‑referencing, evidentiary proof and scope limits.

Timing windows are strict and varied. Several factors require evidence within tight temporal windows: thoracic or invasive cardiac procedure within 1 year before clinical onset/worsening (s9(18); s9(43)); surgical procedure involving general or regional anaesthesia within 30 days (s9(20); s9(45)); cardiac stereotactic ablative radiotherapy or cryotherapy within 6 months (s9(21); s9(46)); penetrating cardiac trauma within 3 months (s9(22); s9(47)); drug exposure within 30 days (s9(23); s9(48)); envenomation by a Viperidae snake within 48 hours (s9(25); s9(49)). Failure to document dates precisely can result in the factor being inoperative. Practitioners must gather start and end dates, theatre and anaesthesia records, ambulance/police reports for envenomation or trauma, and medication administration logs.

Definitions in the Schedule must be matched precisely. The Schedule defines MET, obstructive sleep apnoea, and the specified lists of drugs, infiltrative diseases, autoimmune diseases, thyroid conditions and mineral/electrolyte abnormalities. For example, the specified drug list in the Schedule is finite and includes named drug classes and examples (e.g. acetylcholinesterase inhibitors, beta blockers, digoxin, class 1A/1C/III anti‑arrhythmics, non‑dihydropyridine calcium channel blockers). If a claimant alleges exposure to a drug not listed, the SOP will not treat it as one of the determinative factors unless that exposure is captured by another listed factor or by a different SOP (s11). Similarly, infiltrative diseases are limited to amyloidosis, hereditary haemochromatosis and sarcoidosis (Schedule 1). Claims alleging other infiltrative processes must be matched to the Schedule language.

Strenuous physical activity test is onerous to prove. Clause s9(24) requires activity greater than 6 METs averaged for at least 20 hours per week for a continuous period of at least 5 years before clinical onset, and if ceased, the onset must occur within 5 years of cessation. MET calculation and retrospective quantification of hours per week over five continuous years are inherently evidentiary challenges. The Schedule defines MET quantitatively, but gathering contemporaneous evidence (training logs, unit physical fitness records, service diaries) will be necessary. Without this, relying on lay recollection may be insufficient.

Obstructive sleep apnoea requires objective sleep study data. The Schedule defines obstructive sleep apnoea “characterised on sleep study by repetitive cessation or decrease of airflow during sleep, despite respiratory effort.” An undiagnosed or suspected OSA without a sleep study report will not meet the explicit Schedule definition.

Electrolyte abnormalities must match the specified list. The Schedule limits mineral/electrolyte abnormalities to hyperkalaemia, hypocalcaemia or hypokalaemia. A claimant with, for instance, hyponatraemia cannot rely on this factor. The claimant must produce laboratory data showing the specified abnormality at the relevant time.

Ambiguity over “inability to obtain appropriate clinical management.” Section s9(50) lists “inability to obtain appropriate clinical management for sick sinus syndrome” as a factor for clinical worsening. The SOP does not define “appropriate,” nor does it specify a timeframe or the context in which inability must be shown. This introduces uncertainty: whether systemic constraints, remote posting, denial of care, or late referral suffice will be a matter for adjudication and may generate contested factual inquiries.

Cross‑SOP references can alter the outcome. Section 11 requires application of other SOPs where a factor overlaps. Practitioners must map each factor against the corpus of current SOPs. That can mean that a factor listed here will be governed by another SOP’s factors and temporal rules “as in force from time to time,” which can change the effective test without notice if other SOPs are amended.

Scope exclusions and pre‑existing disease rules. s7(2)(b) excludes congenital sick sinus syndrome. Section 10(2) limits the application of clinical worsening factors to cases where the SSS was suffered or contracted before or during relevant service but did not arise out of it. Determining whether SSS “arose out of” service or pre‑existed service is a critical factual question. Mischaracterising the temporal relationship can lead to misapplication of s9(26)-(50).

Death causation requires contribution to a terminal event. For death claims, s7(5) requires that the terminal event or condition be contributed to by the person’s SSS. The Schedule lists terminal events such as pneumonia or cardiac arrest, but practitioners must demonstrate how SSS materially contributed to that terminal event rather than that the terminal event was unrelated.

Specified lists are finite not illustrative. Several parts of the Schedule use clear enumerations (e.g. specified list of drugs, infiltrative diseases, autoimmune diseases). The instrument presents those lists as the determinative ones. Where a claimant’s exposure/disease is outside the specified list, reliance on that factor as a basis for raising a reasonable hypothesis will likely fail unless another factor in s9 applies.

Documentation quality matters. The SOP emphasises that documented sinus node dysfunction correlates with symptoms (s7(2) Note 2). This signals that objective cardiac evidence (ECG, Holter monitor, electrophysiology) will carry weight. Poorly documented or retrospective clinical notes will be less persuasive.

To comply with, and make reasonable use of, this SOP when preparing or adjudicating a claim under the VEA s120A or MRCA s338, parties should adopt a structured evidence‑gathering and analysis plan keyed to the SOP’s enumerated factors and definitions. Below are concrete steps, tied to specific provisions.

1. Establish the relevant claim framework. Confirm that the claim is one to which s120A VEA or s338 MRCA applies (s5). If not, this SOP does not apply. If the claim does fall under those sections, proceed to map the claim to the SOP’s factors.

2. Confirm the clinical diagnosis and timing. Gather objective cardiological evidence that SSS exists as defined in s7(2). This should include ECG strips, Holter monitor reports, electrophysiology studies, cardiology specialist letters, pacemaker implantation records (if any), and contemporaneous documentation of relevant symptoms (fatigue, syncope, presyncope, dyspnoea, palpitations) that correlate with documented sinus node dysfunction (s7(2) Note 2). Precisely date the clinical onset and any clinical worsening events.

3. Identify which SOP factor(s) in s9 are being relied upon. Review s9(1)-(25) for factors relevant to clinical onset and s9(26)-(50) for factors relevant to clinical worsening. For each chosen factor, assemble the specific evidence types described below.

4. Collect factor‑specific evidence:

• Atrial fibrillation/flutter (s9(1), s9(26)): ECG/Holter/clinic notes showing AF/AFL at the time of clinical onset or worsening.
• Hypertension, ischaemic heart disease, heart failure (s9(2)-(4); s9(27)-(29)): specialist letters, diagnostic test results (echocardiogram, coronary imaging), medication lists, hospital discharge summaries.
• Rheumatic fever, pericarditis, cardiomyopathy (s9(5)-(7); s9(30)-(32)): relevant hospital records, serology, histology, imaging, clinical summaries with dates.
• Myocarditis (non‑infectious or viral) and non‑viral myocarditis/infections (s9(8)-(10); s9(33)-(35)): biopsy, cardiac MRI, serology, microbiology, immunotherapy exposure notes (immune checkpoint inhibitors), infectious disease reports naming pathogens where possible (the Schedule lists examples such as SARS‑CoV‑2, HIV, group B coxsackie, dengue, Borrelia, Toxoplasma, Trypanosoma cruzi).
• Infiltrative disease (s9(11); s9(36)): histology, imaging, specialist letters confirming one of the specified infiltrative diseases (amyloidosis, hereditary haemochromatosis, sarcoidosis).
• Neoplasm or compressive lesion involving the sinoatrial node (s9(12)-(13); s9(37)-(38)): imaging, biopsy, operative records, oncology notes.
• Thoracic or invasive cardiac procedures, heart transplant (s9(18)-(19); s9(43)-(44)): operative notes, theatre records, procedure dates; ensure within the 1‑year window for procedures (s9(18)/s9(43)).
• General/regional anaesthesia (s9(20); s9(45)): anaesthetic records and procedure dates within 30 days.
• Cardiac stereotactic ablative radiotherapy or cryotherapy (s9(21); s9(46)): radiotherapy records, procedural reports within 6 months.
• Penetrating cardiac trauma (s9(22); s9(47)): emergency, surgical, police or incident reports showing trauma within 3 months.
• Drug exposure (s9(23); s9(48)): pharmacy dispensing records, inpatient medication charts, general practice prescriptions confirming drugs from the Schedule were taken within 30 days before onset/worsening. The Schedule provides a finite list of drugs and classes.
• Envenomation by Viperidae (s9(25); s9(49)): clinical records and acute incident reports verifying envenomation within 48 hours.
• Strenuous physical activity >6 METs averaged 20 hrs/week for 5 years (s9(24)): training logs, service physical training records, unit rosters, sporting records, or other contemporaneous documentation that can be converted to METs; demonstrate the continuous nature over 5 years and timing relative to onset, or cessation within 5 years if activity stopped.
• Obstructive sleep apnoea (s9(16); s9(41)): sleep study (polysomnography) reports consistent with the Schedule’s definition.
• Mineral/electrolyte abnormalities (s9(17); s9(42)): laboratory data showing hyperkalaemia, hypokalaemia or hypocalcaemia at the relevant time.
• Autoimmune or thyroid conditions from specified lists (s9(14)-(15); s9(39)-(40)): specialist endocrinology or rheumatology records confirming a listed condition (e.g. rheumatoid arthritis, lupus, systemic sclerosis; hyperthyroidism including Graves, hypothyroidism including Hashimoto, or thyrotoxicosis).
• Inability to obtain appropriate clinical management (s9(50)): document attempts to obtain care (referral records, appointment cancellations, evidence of lack of local facilities, correspondence), together with clinical notes showing deterioration consistent with lack of management.

5. Establish relationship to relevant service. For any factor relied on, prepare evidence to show it is connected to service circumstances (s10(1)). This can include service medical records, deployment logs, environmental exposure reports, incident reports, or occupational health files linking the factor to the relevant service period or events. For s9(26)-(50), ensure the record establishes that SSS was suffered or contracted before/during service and did not arise out of it, so that factors apply to material contribution or aggravation (s10(2)).

6. Map any cross‑references to other SOPs. Use s11 to identify whether a listed factor is itself the subject of another SOP. Where so, obtain and apply the current version of that SOP and align the evidence collection with its requirements.

7. Prepare a clear chronology and causal narrative. Construct a timeline that links onset/worsening dates to the factor(s) and to relevant service dates, and that explains how the factor is hypothesised to connect SSS to service. For death claims under s7(5), prepare medical cause‑of‑death documentation and evidence showing SSS contributed to the terminal event listed in the Schedule.

8. Use specialist opinion. Obtain contemporaneous or retrospective cardiology specialist opinions that interpret the objective evidence against the SOP’s factors. Because the SOP ties significance to documented sinus node dysfunction (s7(2) Note 2), specialist interpretation of ECG/Holter/EP data will be material.

9. Anticipate and address evidentiary limits. Where objective data are missing (for example, no sleep study or incomplete medication records), obtain corroborative evidence,hospital admission notes, GP letters, pharmacy searches, third‑party logs, unit records,rather than relying solely on lay statements. Where the SOP’s language is ambiguous (for example s9(50) “inability to obtain appropriate clinical management”), provide detailed contemporaneous documentation of system failures or lack of access.

10. Keep contemporaneous records and preserve originals. Because the SOP hinges on dates and specific tests, preserving original clinical records, imaging, and pathology reports will reduce contestability when the claim is assessed.

11. Review legal options for disagreement. If a decision‑maker does not accept that a reasonable hypothesis has been raised despite the above evidence, the claimant should consult the appeal and review pathways available under the VEA and MRCA. The SOP does not prescribe appeal mechanisms; those are located in the primary legislation and administrative rules.

By following these steps, claimants and their advisers will align their evidence and presentation with the SOP’s explicit requirements, increasing the prospects that the decision‑maker will find that a reasonable hypothesis has been raised connecting SSS or death from SSS to relevant service as framed by this instrument.