Citation Nr: 21076610 Decision Date: 12/27/21 Archive Date: 12/27/21 DOCKET NO. 18-37 482 DATE: December 27, 2021 REMANDED Entitlement to service connection for hypertension, to include as due to herbicide exposure is remanded. Entitlement to service connection for thoracic aortic aneurysm as secondary to hypertension is remanded. REASONS FOR REMAND The Veteran served on active duty from October 1963 to October 1967, including in the Republic of Vietnam. This matter comes before the Board of Veterans' Appeals (Board) on appeal from an August 2014 rating decision issued by a Department of Veterans Affairs (VA) Regional Office (RO). The claims were previously remanded by the Board in April 2019 and November 2020. 1. Entitlement to service connection for hypertension, to include as due to herbicide exposure is remanded. The Veteran asserts that his hypertension is the result of herbicide exposure during service. Pursuant to 38 C.F.R. § 3.309 (e), if a Veteran was exposed to an herbicide agent (including Agent Orange) during active service, certain enumerated diseases shall be service connected if the requirements of 38 U.S.C. § 1116, 38 C.F.R. § 3.307 (a)(6)(iii) are met, even though there is no record of such disease during service, provided further that the rebuttable presumption provisions of 38 U.S.C. § 1113; 38 C.F.R. § 3.307 (d) are also satisfied. Although the Veteran is presumed to have been exposed to herbicides during his service in the Republic of Vietnam, the Board notes that hypertension is not an enumerated disease for which presumptive service connection for exposure to an herbicide agent is available. However, the Board observes that the National Academies of Sciences, Engineering, and Medicine upgraded the likelihood of an association between hypertension and exposure to an herbicide agent from "limited or suggestive" to "sufficient" evidence of an association. 38 C.F.R. § 3.309 (e); see Veterans and Agent Orange: Update 11 (2018). Where the evidence does not warrant presumptive service connection, a Veteran is not precluded from establishing service connection for disability due to exposure to herbicides with proof of direct causation. Combee v. Brown, 34 F.3d 1039, 1041 (Fed. Cir. 1994). A claimant is permitted to demonstrate in-service incurrence or aggravation through actual evidence of Agent Orange exposure, and a claimant may establish a nexus to service by actual evidence of a link between a present disability and the in-service event. See Combee, 34 F.3d at 1043-44; 38 C.F.R. § 3.303 (d). The Board notes that a VA medical opinion was obtained in July 2020, but in the November 2020 decision, the Board determined that the opinion was inadequate. A new VA medical opinion was obtained in May 2021. However, the Board also finds the May 2021 opinion is not sufficient to adjudicate the claim. The May 2021 VA examiner opined that the Veteran's hypertension is less likely than not related to service, to include herbicide exposure. Although the examiner acknowledged that the Veteran was exposed to herbicides during service, no explanation was provided as to why that exposure was not the cause of the Veteran's hypertension. Instead, the examiner stated that the Veteran's in-service blood pressure readings were normal, and listed several risk factors for how hypertension develops in men. The examiner did not indicate which, if any, of the listed risk factors were the likely cause of the Veteran's hypertension. The Board finds this opinion is inadequate, as it is not supported by sufficient rationale. Although the Board regrets the additional delay, remand is required to obtain a new medical opinion. See Stegall v. West,11 Vet. App. 268, 271 (1998). 2. Entitlement to service connection for thoracic aortic aneurysm as secondary to hypertension is remanded. Because the hypertension service connection claim is being remanded, the service connection claim for thoracic aortic aneurysm, which the Veteran asserts is secondary to hypertension, must also be remanded as the claims are inextricably intertwined. The Board notes that VA medical opinions have been provided that indicate the Veteran's thoracic aortic aneurysm is caused by the Veteran's hypertension. Therefore, new opinions will not be requested on remand. The matters are REMANDED for the following action: 1. Obtain an addendum opinion from a VA examiner to determine the nature and etiology of the Veteran's hypertension. The examiner must review the claims file and note that review in the report. The examiner should be aware that herbicide exposure is conceded. Following a review of the file, the examiner should respond to the following: (a.) Is it at least as likely as not (50 percent probability or more) that the Veteran's hypertension began in service, was caused by service, or is otherwise related to service, to include the Veteran's presumed Agent Orange exposure from his Vietnam service? (b.) Any opinion expressed by the VA examiner must be supported by sufficient rationale, containing clear conclusions, and supporting data. (c.) Attention is drawn to the National Academies of Sciences, Engineering, and Medicine decision to upgrade the likelihood of an association between hypertension and exposure to an herbicide agent from "limited or suggestive" to "sufficient" evidence of an association. 38 C.F.R. § 3.309 (e); see Veterans and Agent Orange: Update 11 (2018). Cynthia M. Bruce Veterans Law Judge Board of Veterans' Appeals Attorney for the Board N. Miller, 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.