ATRIAL FIBRILLATION OR ATRIAL FLUTTER

YVETTE R. WHITE · 2026 · Case ID: 26004161

DENIED

Summary

The Veteran, a Navy Veteran who served from November 1967 to September 1971, appeals the denial of service connection for atrial fibrillation, including a claim based on herbicide exposure. The Veteran contends his condition is due to Agent Orange exposure, citing his service on the USS Ranger and work on aircraft that flew to Vietnam. However, extensive VA development, including reviews of command histories, ship logs, and TERA memoranda, failed to corroborate any herbicide exposure. The Board found the Veteran's lay statements regarding exposure lacked probative value as they were speculative and not supported by specific evidence or scientific links to his condition. The Veteran's service treatment records showed a functional heart murmur during service, which was deemed not disqualifying. His atrial fibrillation was diagnosed post-service in 2009. The Board found the persuasive weight of the evidence, including multiple VA medical opinions, weighed against a service connection. The VA examiners opined that the atrial fibrillation was less likely than not related to service, citing the Veteran's in-service murmur as functional and noting significant non-military risk factors such as age, hypertension, and family history. Private medical opinions submitted by the Veteran were previously found conclusory. The Board denied service connection for atrial fibrillation.

Rationale

No competent evidence of herbicide exposure during service.; Lay statements regarding exposure lacked probative value.; In-service murmur deemed functional, not organic heart disease.; Post-service risk factors (age, hypertension, sleep apnea, family history) outweigh service connection.; VA medical opinions found less likely than not related to service.

Service Branch

NAVY

Special Benefit

NO SPECIAL BENEFIT

Docket No.

18-47 158

Full Decision Text

Citation Nr: 26004161
Decision Date: 04/03/26 Archive Date: 04/03/26

DOCKET NO. 18-47 158
DATE: April 3, 2026

ORDER

Entitlement to service connection for a heart condition diagnosed as atrial fibrillation, to include as due to exposure to herbicide agents, is denied.

FINDINGS OF FACT

1. The Veteran is not presumed or actually shown to have been exposed to herbicide agents in service.

2. The Veteran's atrial fibrillation did not have its onset during service and is not otherwise shown to be related to active service.

CONCLUSION OF LAW

The criteria for service connection for atrial fibrillation have not been met. 38 U.S.C. §§ 1110, 5107; 38 C.F.R. §§ 3.102, 3.303.

REASONS AND BASES FOR FINDINGS AND CONCLUSION

The Veteran served on active duty in the United States Navy from November 1967 to September 1971.

This matter comes before the Board of Veterans' Appeals (Board) on appeal from an April 2018 rating decision issued by a Department of Veterans Affairs (VA) Regional Office (RO), the Agency of Original Jurisdiction (AOJ). In December 2021, the Veteran testified at a hearing before the undersigned Veterans Law Judge (VLJ). A transcript of the hearing is of record.

In an August 2022 Board decision, the Veteran was denied entitlement to service connection for a heart condition diagnosed as atrial fibrillation, to include as due to exposure to Agent Orange herbicides. The Veteran appealed the decision to the United States Court of Appeals for Veterans Claims (Court).

In July 2023, the Court granted the parties' June 2023 Joint Motion for Remand (JMR), vacating the Board's August 2022 decision denying the claim and remanding the matter back to the Board for further development and readjudication.

This matter was again before the Board in December 2023 and (most recently) in September 2025. Consistent with the terms of the June 2023 JMR, the Board remanded the matter to obtain an adequate VA medical opinion on direct service connection. The Board also remanded the matter to the AOJ to adequately clarify the Veteran's in-service exposure(s) to herbicide agents, if any, and to issue a corrected TERA memorandum as needed. See September 2025 Board Decision.

Subsequently, the AOJ obtained new VA medical opinions on direct service connection in November 2025 (with addenda opinions in December 2025 and in January 2026) and in January 2026. In addition, the AOJ issued a corrected TERA memorandum on October 3, 2025. Thus, the Board finds that there has been substantial compliance with the remand directives. See Stegall v. West, 11 Vet. App. 268 (1998).

Entitlement to service connection for atrial fibrillation, to include as due to exposure to herbicide agents, is denied.

The Veteran contends that his heart condition is due to his exposure to Agent Orange. See December 2021 Hearing Transcript.

Service Connection

Service connection will be granted if the evidence demonstrates that a current disability resulted from an injury or disease incurred in active military service. 38 U.S.C. § 1110; 38 C.F.R. § 3.303(a). Establishing service connection generally requires competent evidence of three things: (1) a current disability; (2) in-service incurrence or aggravation of a disease or injury; and (3) a relationship between the current disability and the in-service disease or injury. Shedden v. Principi, 381 F.3d 1163, 1166-67 (Fed. Cir. 2004). Consistent with this framework, service connection is warranted for a disease first diagnosed after discharge when all of the evidence, including that pertinent to service, establishes that the disease was incurred in service. 38 C.F.R. § 3.303(d).

In addition, if a veteran was exposed to an herbicide agent during active military, naval, or air service, certain enumerated diseases, including ischemic heart disease (IHD), shall be service connected if the requirements of §3.307(a)(6) are met even though there is no record of such disease during service, provided further that the rebuttable presumption provisions of §3.307(d) are also satisfied. 38 U.S.C. § 1116; 38 C.F.R. § 3.309(e).

A Veteran who during active military, naval, or air service
that pertinent to service, establishes that the disease was incurred in service. 38 C.F.R. § 3.303(d).

A Veteran who during active military, naval, or air service, served in the Republic of Vietnam (including the inland waterways or the 12-nautical mile territorial sea thereof) during the period beginning on January 9, 1962, and ending on May 7, 1975, shall be presumed to have been exposed during such service to an herbicide agent, unless there is affirmative evidence to establish that the Veteran was not exposed to any such agent during that service. 38 U.S.C. § 1116(f); 38 C.F.R. § 3.307(a)(6)(iii). For Veterans who have been exposed to an herbicide agent (to include Agent Orange) during active service, presumptive service connection is available for certain enumerated diseases including IHD. See 38 C.F.R. § 3.309(e).

Nevertheless, a presumption of service connection provided by law is not the sole method for showing causation in establishing a claim for service connection for disability due to herbicide exposure. See Stefl v. Nicholson, 21 Vet. App. 120 (2007) (holding that the availability of presumptive service connection for some conditions based on exposure to Agent Orange does not preclude direct service connection for other conditions based on exposure to Agent Orange).

When there is an approximate balance of positive and negative evidence regarding any issue material to the determination of a matter, the benefit of the doubt shall be given to the claimant. 38 U.S.C. § 5107(b).

Exposure to Herbicide Agents

As a preliminary matter, the Board has considered whether the evidence of record indicates that the Veteran was exposed to herbicide agents during service. For the following reasons, the Board finds that the totality of the evidence fails to establish the Veteran's exposure to herbicide agents during service.

The Veteran does not contend that he served in an area that would entitle him to a presumption of exposure to herbicide agents under governing law and regulation. See, e.g., July 2022 IHP. Rather, the Veteran contends that he was exposed to herbicide agents when serving on an aircraft carrier, the USS Ranger, as an aviation electrician mate, during which he worked on aircraft that would fly off the ship over to Vietnam and back. See December 2021 Hearing Transcript (further testifying that he was in an F-4 squadron, that he was sure the planes had flown through Agent Orange, and that he would crawl all over the planes when they returned). See also April 2022 VA Form 21-4138 (Veteran's report that he was stationed aboard the USS Ranger CVA 61 from October 1970 until June 1971 and that his duties were aviation electrician mate AE3 for VF 154 F4 Phantoms). The Veteran also contends that "the USS Ranger was exposed to Agent Orange in the Navy... [and]... there was residual toxins in the water system when [the Veteran] was on board." See July 2022 IHP.

VA conducted extensive development to determine if exposure to Agent Orange herbicides could be verified during the Veteran's active military service.

A June 2022 VA memorandum indicates that exposure to herbicides could not be conceded as the evidence of record did not show the Veteran had duty or visitation in the Republic of Vietnam, or on its inland waterways, or nautical service in the offshore waters as defined in the Blue Water Navy Vietnam Veterans Act of 2019, Public Law 116-23. See June 2022 VA Memorandum (Subject: Herbicide Exposure Verification Memo).

In addition, a June 2022 Records Research Center Response indicates that an employee from the Veterans Benefits Administration, Office of Field Operations, had completed comprehensive research on the Veteran's claimed exposure event, including a review of the 1970 and 1971 Command History Reports submitted by Fighter Squadron-154 and the 1970 and 1971 Command History Reports submitted by the USS Ranger CVA 61. The report concluded that no evidence was located to support documentation of the Veteran's claimed exposure. See June 2022 Records Research Center Response
defined in the Blue Water Navy Vietnam Veterans Act of 2019, Public Law 116-23. See June 2022 VA Memorandum (Subject: Herbicide Exposure Verification Memo).

In addition, a June 2022 Records Research Center Response indicates that an employee from the Veterans Benefits Administration, Office of Field Operations, had completed comprehensive research on the Veteran's claimed exposure event, including a review of the 1970 and 1971 Command History Reports submitted by Fighter Squadron-154 and the 1970 and 1971 Command History Reports submitted by the USS Ranger CVA 61. The report concluded that no evidence was located to support documentation of the Veteran's claimed exposure. See June 2022 Records Research Center Response (additionally stating: "We are unable to concede herbicide exposure for this Veteran based on the Ship Locator Tool and other VBA approved tools.").

In February 2025, a Records Research Response indicates that an employee from the Veterans Benefits Administration, Office of Field Operations, Records Acquisition & Research (RAR), had completed comprehensive research on the Veteran's claimed exposure event, claiming that he was exposed to herbicides while assigned to the USS Ranger (CVA-61) from October 1970 through June 1971. It stated that VBA partnered with the classified records archivists at Naval History and Heritage Command (NHHC), the custodian of classified records for Navy vessels/units, and that their classified researcher was unable to confirm the RVN/blue water exposure claimed by the veteran. It also notes that areas of exposure associated with the Sergeant First Class Heath Robinson Honoring Our Promise to Address Comprehensive Toxics (PACT) Act of 2022 were reviewed, and that their classified researcher was unable to confirm exposure in a location(s) associated with the PACT Act. See Records Research Center Response received February 25, 2025.

In March 2025, a Records Research Memo indicates that a review of the 1970 and 1971 Command History for VF 154 and the USS Ranger CVA 61 showed no qualifying service. See VA Memo received March 17, 2025.

Also in March 2025, a VA Herbicide Exposure Verification Memorandum indicates that: (1) exposure to herbicides could not be recognized as the evidence of record did not show the Veteran had service in a qualifying nautical location; and (2) exposure to herbicides could not be conceded as the evidence of record did not show the Veteran had duty or visitation in the Republic of Vietnam, or on its inland waterways, or nautical service in the offshore eligible waters as defined in the Blue Water Navy Vietnam Veterans Act of 2019, Public Law 116-23. See VA Herbicide Exposure Verification Memorandum received March 18, 2025.

Finally, the Board notes that the claims file includes numerous TERA memoranda (some contradictory and some internally inconsistent). Following the September 2025 Board remand, the AOJ issued a corrected TERA memorandum on October 3, 2025, which indicates that the Veteran did not qualify for a presumption of exposure for Herbicide Agent - 2,3,7,8 - Tetrachlorodibenzodioxin (TCDD). It also indicates that ILER entries did not corroborate toxic exposure to occupational or environmental hazards, i.e., "no ILER." See October 3, 2025 TERA Memorandum.

In sum, the Board finds that the evidence fails to establish the Veteran's exposure to herbicide agents during his service in the Fighter Squadron 154 from June 1970 to September 1971 and while deployed on board the USS Ranger CVA 61 from September 1970 to June 1971.

The Board acknowledges the Veteran's lay statements that he believes he was exposed to Agent Orange through his work on aircraft that flew into Vietnam and through contaminated water. See, e.g., July 2023 IHP.

The Board does not doubt the Veteran's sincere belief that he was exposed to herbicides when he served aboard the USS Ranger, and it acknowledges that a layperson is competent to report on matters of which he has personal knowledge. See Layno v. Brown, 6 Vet. App. 465, 470 (1994) (a Veteran is competent to report on that of which he or she has personal knowledge). However, there is no indication in the record that the Veteran is competent to determine what, if any, chemicals or substances adhered to the exterior of the aircraft or were present in the potable water through requisite knowledge, training, and expertise. See Bardwell v. Shinseki, 24 Vet. App. 36, 40 (2010) (holding that the veteran's lay assertions indicating exposure to gases or chemicals during service were
that a layperson is competent to report on matters of which he has personal knowledge. See Layno v. Brown, 6 Vet. App. 465, 470 (1994) (a Veteran is competent to report on that of which he or she has personal knowledge). However, there is no indication in the record that the Veteran is competent to determine what, if any, chemicals or substances adhered to the exterior of the aircraft or were present in the potable water through requisite knowledge, training, and expertise. See Bardwell v. Shinseki, 24 Vet. App. 36, 40 (2010) (holding that the veteran's lay assertions indicating exposure to gases or chemicals during service were not sufficient evidence alone to establish that such an event actually occurred during service). Thus, the Veteran's opinion that he was exposed to herbicides on the USS Ranger lacks probative value.

The Board also acknowledges that in a July 2022 IHP, the Veteran's representative cites to an Australian study, a fact sheet on dioxins, and an Institute of Medicine publication in support of the contention that the Veteran's potable water may have been contaminated aboard the USS Ranger. See July 2022 IHP. However, these references are generalized and speculative. None of these sources mention the USS Ranger specifically or provide direct testing data to demonstrate that its water supply was contaminated. For example, the Australian study assessed results that compared mortality rates of veterans of the Royal Australian Navy (RAN) versus other Australian Vietnam Veterans between the years 1980 and 1994. Moreover, the language used throughout the Institute of Medicine publication, such as "plausible," "may have," and "could be," is noncommittal and fails to provide the specificity required to establish actual exposure in this case. The articles also do not address the Veteran's primary theory of exposure through direct physical contact with returning aircraft. Therefore, the Board finds that the cited evidence lacks probative value in the Veteran's case.

In sum, the competent evidence of record fails to establish exposure to herbicide agents during the Veteran's service. Accordingly, the Veteran's claim for service connection based on in-service exposure to herbicides agents must be denied.

Other Bases for Direct Service Connection

Although herbicide exposure has not been shown, the Board has considered whether there is otherwise a direct link between the Veteran's atrial fibrillation and active service.

Relevant Factual Background

The Veteran's July 1967 enlistment examination showed that his heart was abnormal on clinical evaluation. A handwritten note on the signature page referenced a "cardiac consult." A stamp under the handwritten note indicates that a physical inspection on November 27, 1967, found no additional defects and deemed the Veteran fit for military service. On the same page under Summary of Defects and Diagnoses, the examiner notes an apical systolic murmur and described it as "functional" and "NDQ" (or not disqualifying). See STR-Medical received February 21, 2018.

An undated cardiology consultation report in the Veteran's service treatment records indicates that he was seen in connection with a systolic, apical murmur. The report indicates that no murmurs were heard at rest, that the heart was not enlarged, that after exercise a brief systolic murmur was heard, localized to the apex, that the murmur disappeared soon afterwards, and that there were no thrills. The military cardiologist concludes that the Veteran did not have any organic heart disease and notes that the Veteran's condition was "NDQ." See STR-Medical received February 21, 2018.

The Veteran's August 1971 separation examination shows that his heart was normal on clinical evaluation. In addition, a chest X-ray taken in connection with the separation examination was within normal limits. See STR-Medical received February 21, 2018.

A March 2018 VA treatment record notes that the Veteran reported a history of atrial fibrillation since 2009 and also reported undergoing surgery to implant a pacemaker in 2015. The treatment record notes a family history of coronary artery disease (CAD) and congestive heart failure (CHF). See VA treatment record dated March 26, 2018 (Primary Care New Visit Note). See also December 2021 Hearing Transcript (testimony from the Veteran that he first experienced heart problems in 2009).

In September 2018, the Veteran had a consultation with the VA cardiology clinic to establish care. The Veteran reported that he was diagnosed with atrial fibrillation in 2009. The VA cardiologist confirmed a diagnosis of atrial fibrillation. See VA treatment record dated September 26, 201
and also reported undergoing surgery to implant a pacemaker in 2015. The treatment record notes a family history of coronary artery disease (CAD) and congestive heart failure (CHF). See VA treatment record dated March 26, 2018 (Primary Care New Visit Note). See also December 2021 Hearing Transcript (testimony from the Veteran that he first experienced heart problems in 2009).

The Veteran was provided a VA examination in April 2018 for his heart disability claim. See April 2018 VA Heart Conditions (Including Ischemic and Non-Ischemic Heart Disease, Arrhythmias, Valvular Disease and Cardiac Surgery) Disability Benefits Questionnaire (DBQ). The examiner notes the Veteran's diagnosis of atrial fibrillation since 2009 and his implanted cardiac pacemaker in 2015 due to atrial fibrillation. The examiner also indicates that the Veteran's heart disability did not qualify within the generally accepted medical definition of ischemic heart disease (IHD). Id.

The April 2018 VA examiner opines that the Veteran's atrial fibrillation was less likely than not incurred in or caused by the claimed in-service injury, event, or illness. See April 2018 VA Medical Opinion DBQ. This opinion was later deemed inadequate in the parties' June 2023 Joint Motion for Remand (JMR).

Another VA medical opinion was obtained in April 2025, in which a VA examiner again provides a negative nexus opinion. This opinion was later deemed inadequate in the Board's September 2025 decision.

As noted above, new VA medical opinions on direct service connection were obtained in November 2025 (with addenda opinions in December 2025 and in January 2026) and in January 2026.

In November 2025, a VA examiner opines that the Veteran's atrial fibrillation was less likely than not incurred in or caused by service. The examiner explains that the Veteran's service treatment records and separation notes did not indicate cardiac issues or arrhythmias. He notes that the Veteran was evaluated for apical systolic murmur during service, which was heard best after exercise but subsided soon thereafter, and that no organic heart condition was found. He explains that atrial fibrillation results in irregular heart rate; in contrast, a murmur is not the result of irregular heartbeat but rather is the result of turbulence created as blood flow is disturbed by openings in the heart or stenosis in valves.

The examiner also explains that the Veteran's medical treatment notes indicate a history of sleep apnea, hypertension, sick sinus syndrome, and chronic kidney disease; that other risk factors includes being over 65 years of age; and that these risk factors and comorbidities had a higher likelihood of causing atrial fibrillation than the Veteran's time in service. See November 2025 VA Medical Opinion DBQ.

In a December 2025 addendum opinion, the same examiner opines that the Veteran's atrial fibrillation was less likely than not due to exposure to asbestos during service. See December 2025 VES Addendum Opinion. He explains that asbestos is more commonly associated with respiratory conditions and that no known direct link has been established between asbestos and atrial fibrillation. He again explains that the Veteran's other risk factors and comorbidities, including sleep apnea, hypertension, sick sinus syndrome, chronic kidney disease, and age, had a higher likelihood of causing his atrial fibrillation.

The examiner also discusses the undated evaluation of the Veteran's murmur again, noting that the Veteran was evaluated for apical systolic murmur, which was heard best after exercise but subsided soon after, that no organic heart condition was noted, and that this would most likely describe a functional murmur or "athlete's heart," and have no meaningful significance. He further notes that an October 2025 echocardiogram showed no structural issues with the heart. See December 2025 VES Addendum Opinion. See also January 2026 VES Addendum Opinion (citing an NIH publication on the causes and risk factors of atrial fibrillation).

In January 2026, a different VA examiner similarly opines that it was less likely than not that the Veteran's atrial fibrillation had its onset during, or was otherwise related to, his active duty service, to include the indicated toxic exposure risk activity(ies), after considering the total potential exposure through all applicable
that this would most likely describe a functional murmur or "athlete's heart," and have no meaningful significance. He further notes that an October 2025 echocardiogram showed no structural issues with the heart. See December 2025 VES Addendum Opinion. See also January 2026 VES Addendum Opinion (citing an NIH publication on the causes and risk factors of atrial fibrillation).

In January 2026, a different VA examiner similarly opines that it was less likely than not that the Veteran's atrial fibrillation had its onset during, or was otherwise related to, his active duty service, to include the indicated toxic exposure risk activity(ies), after considering the total potential exposure through all applicable military deployments of the Veteran and the synergistic, combined effect of all toxic exposure risk activities of the Veteran. See January 2026 VA Medical Opinion DBQ. The examiner explains that there is no medical or scientific evidence available which provides any indication of a relationship between the development of atrial fibrillation and asbestos exposure. The examiner also cites publications relating to asbestos exposure. The examiner explains that while asbestos exposure can primarily lead to lung cancer, there is no known mechanism by which it could cause atrial fibrillation.

The examiner also explains that the Veteran had multiple risk factors outside of military service (hereditary, congenital, weight, lab findings, and multifactorial) that far outweighs the factors such as the Veteran's asbestos exposure during service. He explains that those non-military risk factors that are unique to this Veteran includes his poorly controlled hypertension, thyroid condition, sleep apnea, advanced age, and family history of cardiovascular disease. See January 2026 VA Medical Opinion DBQ.

Analysis

As noted above, establishing service connection generally requires competent evidence of three things: (1) a current disability; (2) in-service incurrence or aggravation of a disease or injury; and (3) a relationship between the current disability and the in-service disease or injury. Shedden v. Principi, supra.

Regarding the first element of service connection, the Veteran has a diagnosis of atrial fibrillation. See April 2018 VA Heart Conditions DBQ. Thus, the first element has been met.

Regarding the second element of service connection, the Veteran had an undated cardiology consult for a heart murmur during active service. See STR-Medical received February 21, 2018. In addition, the Veteran's in-service exposure to asbestos is conceded based on his MOS of aviation electrician's mate. See October 2025 TERA Memorandum. Thus, the second element has been met.

The remaining question is whether there is a nexus between the Veteran's atrial fibrillation and his active duty service. Here, the probative evidence is against finding that the Veteran's atrial fibrillation began during active service or is otherwise related to service, to include his cardiology consultation and conceded exposure to asbestos.

In this regard, the November 2025 and January 2026 VA examiners opine that it was less likely than not that the Veteran's atrial fibrillation had its onset during, or was otherwise related to, his active duty service, to include the cardiology consultation for apical systolic murmur and conceded in-service exposure to asbestos. The Board finds that the November 2025 opinion (as modified by the addenda opinions in December 2025 and in January 2026) and the January 2026 opinion are entitled to probative weight, as both considered the Veteran's history and the medical evidence and provided an explanation that contains clear conclusions and supporting data. See Nieves-Rodriguez v. Peake, 22 Vet. App. 295, 304 (2008) (most of the probative value of a medical opinion comes from its reasoning).

The Board acknowledges that the Veteran submitted two private opinions, in which the physicians opine that the Veteran's heart condition was caused by his exposure to Agent Orange during military service. See December 2021 Private Opinion; August 2023 Private Opinion. The Board previously found these opinions to be conclusory and, therefore, inadequate for adjudication purposes. See December 2023 Board Decision. Moreover, as discussed above, the Veteran's in-service exposure to herbicide agents has not been shown.

In sum, there is no competent probative evidence to support a finding that the Veteran incurred atrial fibrillation during or as a result of his military service, to include exposure to asbestos. Rather, the evidence persuasively weighs against a finding of a military nexus for any post-service atrial fibrillation. As the persuasive weight of the evidence is against the instant claim and is neither evenly balanced nor approximately so on this question, the benefit-of-the-doubt doctrine is
. The Board previously found these opinions to be conclusory and, therefore, inadequate for adjudication purposes. See December 2023 Board Decision. Moreover, as discussed above, the Veteran's in-service exposure to herbicide agents has not been shown.

In sum, there is no competent probative evidence to support a finding that the Veteran incurred atrial fibrillation during or as a result of his military service, to include exposure to asbestos. Rather, the evidence persuasively weighs against a finding of a military nexus for any post-service atrial fibrillation. As the persuasive weight of the evidence is against the instant claim and is neither evenly balanced nor approximately so on this question, the benefit-of-the-doubt doctrine is not for application. Lynch v. McDonough, 21 F.4th 776, 781-82 (Fed. Cir. 2021) (only when the evidence persuasively favors one side or the other is the benefit of the doubt doctrine not for application).

(Continued on the next page)

The Board is grateful to the Veteran for his service and regrets that it cannot render a favorable decision in this matter.

YVETTE R. WHITE

Veterans Law Judge

Board of Veterans' Appeals

Attorney for the Board C.D., Associate Counsel

The Board's decision in this case is binding only with respect to the instant matter decided. This decision is not precedential and does not establish VA policies or interpretations of general applicability. 38 C.F.R. § 20.1303.

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