Leadbetter, Inc. and its insurer (hereinafter collectively referred to as “employer”) appeal a decision of the Workers’ Compensation Commission awarding temporary total disability benefits to Benjamin Penkalski (claimant). Employer contends that the commission erred in finding that (1) American Furniture Co. v. Doane, 230 Va. 39, 334 S.E.2d 548 (1985), does not control this case; (2) the “two causes” rule applies to this case and requires reinstatement of temporary total disability benefits; (3) the claimant’s work-related ankle injuries, in part, caused his inability to continue performing the light duty job he had been performing until his December 11, 1992 heart attack; (4) any amount of the claimant’s partial disability attributable to his compensable ankle injuries was sufficient to support reinstatement of temporary total disability benefits; (5) a portion of the claimant’s loss of earning capacity after December 11, 1992 was attributable to his compensable ankle injuries; and (6) the claimant had no residual work capacity after his heart attack, and therefore he had no obligation to *457market his residual work capacity. For the reasons stated below, we find that the Supreme Court’s holding in Doane controls this case, and that the “two causes” rule does not apply. Accordingly, we reverse the commission’s decision.
BACKGROUND
Stipulations of the Parties:
On April 9, 1991, the claimant sustained compensable injuries to both ankles while working for employer. The claimant received temporary total disability benefits as a result of those compensable injuries. On May 18, 1992, the commission entered an award providing the claimant with permanent partial disability benefits to compensate him for thirty percent permanent partial loss of function to his left leg and twenty percent permanent partial loss of function to his right leg. The claimant’s entitlement to permanent partial disability benefits ended on September 30,1993. He did not receive any additional disability benefits from employer after September 30, 1993. At all times since April 9, 1991, the claimant was restricted from performing his regular pre-injury work. However, the claimant was permitted by his treating physician, Dr. E. Claiborne Irby, an orthopedic surgeon, to resume light-duty selective employment within his limitations. Employer provided the claimant with light-duty work consistent with his limitations. As of December 10, 1992, the claimant was performing light duty work for employer. On December 11,1992, the claimant suffered a heart attack. As a result of the heart attack, the claimant developed ischemia of his feet. The claimant lost additional function of his feet as a consequence of the ischemia. The heart attack, ischemia, and resulting treatment were not caused by the claimant’s compensable April 9, 1991 accident, and are not work-related.
Medical Records:
Dr. Irby released the claimant to return to restricted work in May 1992. On May 27, 1993, Dr. Irby wrote that the claimant had problems unrelated to his April 9, 1991 accident and problems directly related to his April 9, 1991 accident. Dr. Irby concluded that the claimant was disabled from per*458forming any work that required prolonged standing and walking. On June 11, 1993, Dr. Irby clarified his opinion by writing that “[the claimant’s] disability has two causes, one which is work-related and one which is not.” On September 9, 1993, Dr. Irby wrote that, after taking into account the claimant’s ankle injuries, his heart problems, and ischemia, he was totally disabled from any future employment. Dr. Irby stated that “the ankle part is ... based on my following the patient” and “the cardiac and ischemic foot disability [is based] on Dr. John T. Funai’s report____”
On September 3, 1993, Dr. Funai, a cardiologist, wrote that the claimant developed severe ischemia of the foot as a result of his heart attack, threatening the loss of his foot. Dr. Funai reported that prolonged rest and intensive medical therapy had stabilized the condition. However, Dr. Funai stated that the possibility of future deterioration of the claimant’s cardiac condition and foot condition was unclear. Therefore, Dr. Funai opined that “the combination of [the claimant’s] cardiac condition and the potential loss of a foot prohibits any future employment.”
Claimant’s Testimony:
The claimant testified that in September 1991, employer made selective employment available to him consistent with his restrictions. He stated that he performed this work until he had his heart attack, and that, before the heart attack, he was “getting stronger all the time.” He testified that, before the heart attack, he had been doing exercises that resulted in significant improvement in the condition of his ankles. After the heart attack, the claimant was not able to do the ankle exercises until November 1993. He stated that the ability to move his feet had worsened since December 11,1992, and that both ankles were stiff and swollen. The claimant agreed that, as far as he knew, the light-duty employment provided to him by employer would have continued but for his heart attack.
Proceedings:
On September 10, 1993, the claimant filed an application alleging a change in condition causally related to the April 1, *4591991 compensable accident. He sought temporary total disability benefits for the period beginning October 1, 1993 and continuing. The employer defended the application on the ground that the claimant’s inability to perform light-duty work was caused by his heart attack and its sequelae, which were unrelated to the compensable accident, and that claimant’s condition was tantamount to an unjustified refusal of selective employment. The employer also contended that, at most, the claimant was partially disabled, and that he failed to market his residual work capacity.
The deputy commissioner awarded temporary total disability benefits to the claimant on the basis that Dr. Irby’s opinion brought the case within the “two causes” rule. The full commission affirmed, finding that Doane did not apply. The commission’s holding was based upon a finding that the claimant was unable to continue with light-duty work provided by employer, both because of the industrial injury and because of the non-work-related heart attack. The commission found that the medical evidence showed that the claimant was totally disabled because of the heart attack and its sequelae, as well as the industrial injury. In Doane, the claimant was unable to continue with light-duty work solely because of a non-work-related disability. The commission further found that the claimant had no obligation to market his residual work capacity because these conditions rendered him totally disabled. In her concurring opinion, Commissioner Diamond found that Doane was inapplicable, because the medical evidence proved that the claimant’s work-related condition was exacerbated by a non-work-related cause. In his dissenting opinion, Commissioner Tarr stated that he did not believe that the claimant was entitled to an award of temporary total benefits because he was in the same position as the claimant in Doane.
ANALYSIS
This appeal does not present a case of conflicting evidence or a dispute concerning the commission’s findings of fact. *460When the issue is the sufficiency of the evidence and there is no conflict in the evidence, the issue is purely a question of law. This Court is not bound by the legal determinations made by the commission. “[W]e must inquire to determine if the correct legal conclusion has been reached.”
Cibula v. Allied Fibers & Plastics, 14 Va.App. 319, 324, 416 S.E.2d 708, 711 (1992) (quoting City of Norfolk v. Bennett, 205 Va. 877, 880, 140 S.E.2d 655, 657 (1965) (other citations omitted)), aff'd, 245 Va. 337, 428 S.E.2d 905 (1993).
Here, there is no conflict in the evidence. Therefore, we must determine if the correct legal conclusion has been reached by the commission.
Applicability of Doane:
Claimant bore the burden of proving that he sustained a change in his capacity to work and that such change was due to a condition causally connected with his compensable injury. AMP, Inc. v. Ruebush, 10 Va.App. 270, 273-74, 391 S.E.2d 879, 881 (1990). In Eppling v. Schultz Dining Programs/Commonwealth, we stated as follows:
[W]hen a non-work-related disability prevents a partially disabled employee from returning to his or her pre-injury work or from accepting selective employment, for purposes of the Act, the unrelated disability is not justification for the employee to refuse or not to perform selective employment or to fail to market his or her residual work capacity. Thus, the inability of a disabled employee to do selective work or to market his or her residual capacity due to an unrelated disability is equivalent to an unjustified refusal of selective employment.
18 Va.App. 125, 130, 442 S.E.2d 219, 222 (1994) (citing Doane, 230 Va. at 42-43, 334 S.E.2d at 550-51, and Code § 65.2-510).
The facts of this case place it squarely within the Supreme Court’s holding in Doane. In Doane, a partially disabled employee was precluded from performing selective employment because of an arm impairment causally unrelated to her compensable back injury. The Supreme Court held that “[a]n *461employer is ... absolved of liability for compensation if the employee refuses selective employment because of a physical condition unrelated to the original industrial accident and arising since the accident.” Doane, 230 Va. at 43, 334 S.E.2d at 550.
Here, even though the claimant was partially disabled because of his ankle condition prior to suffering his heart attack, he was able to perform selective employment. After his heart attack, the claimant was precluded from performing selective employment. The claimant stipulated that the heart attack and ischemia were not work-related nor were they related to his compensable ankle injuries. In addition, he stipulated that his additional loss of foot function was caused by the ischemia.
Dr. Funai attributed claimant’s total disability to his heart attack and ischemia. Dr. Funai made no mention of the claimant’s compensable ankle injuries when rendering his opinion. Dr. Irby did not state that the heart attack and its sequelae exacerbated the claimant’s ankle injuries, thereby precluding him from performing selective employment. Dr. Irby merely stated that a portion of claimant’s disability was work-related and a portion of his disability was not work-related. However, Dr. Irby did not opine that claimant’s inability to return to selective employment after his heart attack was caused by claimant’s compensable ankle injuries or by an exacerbation of those injuries.
Based upon this record, we find that the commission erroneously concluded that the physicians reported that the claimant was totally disabled because of the heart attack and its sequelae, as well as the industrial accident. No medical evidence proved that the claimant’s heart attack and its sequelae aggravated or exacerbated his ankle condition, resulting in disability which precluded him from returning to selective employment. In order to have been entitled to an award of temporary total disability benefits, the claimant was required to prove a causal connection between his heart attack and its sequelae and his compensable ankle injuries. The claimant failed to meet this burden. Thus, the claimant’s non-work-*462related heart condition and ischemia did not relieve him of his obligation to perform selective employment or market his residual work capacity. See Eppling, 18 Va.App. at 130, 44S.E.2d at 222.
Applicability of “Two Causes” Rule:
The “ ‘two causes’ rule ‘refers to the case where a disability has two causes: one related to the employment and one unrelated.’ ” Smith v. Fieldcrest Mills, Inc., 224 Va. 24, 28, 294 S.E.2d 805, 808 (1982) (citation omitted) (emphasis added). In such a case, benefits are allowed “when it is shown that ‘the employment is a contributing factor to the disability.’” Id. at 28-29, 294 S.E.2d at 808 (citation omitted).
In order for the “two causes” rule to apply in this case, the claimant was required to present evidence that, after his heart attack, his ankle condition prevented him from returning to selective employment, and that the disability due to his ankle condition had two causes, one work-related and one non-work-related. The medical evidence did not establish that the claimant’s ankle condition resulted in disability that was caused in part by the compensable accident and in part by the heart attack and its sequelae, and that this disability precluded him from returning to selective employment. Dr. Irby opined that the claimant was totally disabled because of his ankle injuries, heart condition, and ischemia. However, he did not opine that the claimant’s ankle condition resulted in total disability that had two causes, one work-related and one not work-related, and that this disability prevented the claimant from returning to selective employment. Therefore, the commission erroneously applied the “two causes” rule as a basis for awarding temporary total disability benefits to the claimant.
Because our holdings on these points dispose of this appeal, we will not address any remaining issues raised by employer in its brief.
We reverse the commission’s award and remand the case for entry of an appropriate order, consistent with the views *463expressed in this opinion, suspending the claimant’s compensation benefits.
Reversed and remanded.