In J. Curren v. WCAB (City of Chester) the Commonwealth Court reversed an Order of the Workers' Compensation Appeal Board that held a mental stress causing physical injury standard of proof applies in a heart attack case. The Court accepted the Claimant's argument that compensation was awarded on a physical stress causing physical injury basis. The Court held the medical testimony credited by the Workers' Compensation Judge provided substantial evidence to support a physical stress causing physical injury standard of proof. Accordingly, the Claimant did not have to meet the heightened burden in a mental/physical case to show abnormal working conditions.