This is a workers’ compensation case with reference to coronary heart disease in which the claimant underwent coronary bypass surgery for “coronary artery disease.” The administrative law judge made findings of fact that from “1979 to July, 1981,” claimant was employed as a supervisor having nine stores located in south Georgia (from Homerville to Americus) all of which “required him to work ten to twelve hours per day . . . [and the] pressure and stress of claimant’s employment duties precipitated and caused claimant’s coronary artery disease to develop which necessitated the coronary bypass [and as a result, on the date of the coronary bypass operation, he] sustained an accidental injury which arose out of and in the course of his employment with this employer.” On appeal to the board the findings of the administrative law judge (with one director dissenting) were made the findings of fact and conclusions of law of the board. The superior court affirmed. We granted a discretionary appeal to review in the light of the recent Supreme Court decision in Southwire Co. v. Cato, 250 Ga. 895 (302 SE2d 91). Held:
In that case (Southwire, supra), after discussion of Guye v. Home Indem. Co., 241 Ga. 213, 215 (244 SE2d 864), the Supreme Court again recited that in heart attack cases “it is often difficult for the trier of fact to find the line between a noncompensable heart injury that is a symptom of an existing disease merely manifested during job exertion, and a compensable heart injury to which the job exertion was a contributing precipitating factor.” The Supreme Court in Guye reversed this court because the employee suffered a heart attack due to exertion and that same was sufficient evidence for the fact finder *618(the board) under the presumptive evidence rule found in former Code § 38-102 (now OCGA § 24-1-1), that is, “evidence which consists of inferences drawn by human experience from the connection of cause and effect and from observations of human conduct,” and at page 217 held there was “competent, creditable evidence as to causation sufficient to be found to satisfy the preponderance of the evidence requirement” of former Code Ann. § 114-102 (Ga. L. 1982, p. 2485) (now OCGA § 34-9-1). OCGA § 34-9-1 (4) provides that an injury shall not “include heart disease . . . the failure or occlusion of any of the coronary blood vessels . . . unless it is shown by a preponderance of competent and credible evidence that any of such conditions were attributable to the performance of the usual work of employment.” In reversing this court, the Supreme Court in Guye concluded the board was “authorized to and did determine that the performance of claimant’s work activities precipitated or contributed to his heart injury . . In Southwire the Supreme Court held that since the heart attack occurred while the claimant was at home there was “uncontradicted medical opinion that the employee’s work did not cause or contribute to his heart injury,” but also held that the ruling in Guye “should not be read as an implication that the natural inference from human experience disappears upon presentation of medical testimony,” then holding “that the ‘natural inference’ is not available where . . . the symptoms of the heart attack did not occur until the claimant had been home several hours.”
The facts in the case sub judice are entirely different from either those of Guye or Southwire. Hence this case is not controlled by Southwire Co. v. Cato, 250 Ga. 895, supra. Both the claimant and his wife had testified to facts obviously establishing extreme stress in that the claimant was working a six-day week, frequently “in excess of ten hours each day,” and “his personality changed,” he became “short tempered, worried and ... [a] different person” after his promotion to his supervisory position. Further, this 38-year-old man began to experience pains in his chest and nervousness and after the second hospitalization for evaluation he underwent the artery bypass operation. It is true other expert testimony was sufficient to establish that his atherosclerosis revealed “a degenerative disease” of the coronary arteries, that is, the depositing of material inside the arteries giving rise to the need for bypass surgery. A medical expert did testify that in his opinion the claimant’s employment did not cause the atherosclerosis. However, he conceded that stress could contribute over a period of time to the development of atherosclerosis. With reference to stress his own doctor stated directly as to causation that stress is “undoubtedly one of the factors contributing to coronary artery disease,” although other risk factors are “common denominators and are more objectively assessed . . . [and in his opinion] these risk factors *619are primarily responsible for his coronary disease,” and further that it is very difficult to quantitate whether his coronary disease was due to the occupational stress or the other risk factors therein mentioned. This expert further testified that “working conditions could have been a precipitating cause of his developing the condition which necessitated coronary bypass surgery and disability.” Accordingly, the board’s award of compensation was supported by evidence. The superior court did not err in affirming that award.
Neither law nor medicine are exact sciences, and we have not reached that degree of certainty where a medical expert can state a definite and certain diagnosis that the claimant’s heart disease did not arise out of and in the course of his employment. This case is similar to that of City Council of Augusta v. Williams, 137 Ga. App. 177, 178 (223 SE2d 227). In the case sub judice, both physicians have expressed opinions that other risk factors were primarily responsible for the claimant’s heart disease, but they did testify that stress is one of the factors contributing to coronary heart disease, and certainly the laymen’s testimony by the claimant and his wife establishes that this claimant was under extreme stress by reason of his promotion to a supervisory position from 1979 to July 1981. The fact finder under OCGA § 24-1-1 (6) (formerly Code § 38-102) was authorized to consider the presumptive evidence consisting of inferences drawn by human experience from the connection of cause and effect and from observations of human conduct as derived from all of the evidence, that is, the lay testimony, as well as the expert opinion testimony and find in this case that the claimant’s heart disease, as of the date of the bypass, resulted in an accidental injury within the definition of the law “which arose out of and in the course of his employment.” The fact finder (the board) is not required to accept the experts’ more definite opinions as overriding their other opinions that stress “could” or “would” have caused the claimant’s heart disease. The weight and credibility of the experts’ testimony along with that of the lay testimony as to stress was for the fact finder, and the fact finder weighed this testimony and accepted same to the exclusion of an expert’s opinion that claimant’s employment did not cause the atherosclerosis. There was direct evidence of the required causal connection between the stress and the resulting heart disease requiring surgery. This is not a heart attack case, and it is not a case of location (location being simply a matter of whether the injury manifested itself on or off the job). Rather, the present case is one of preventive surgery. It is possibly the first instance of bypass surgery in workers’ compensation to be dealt with at length by this court. In effect, what we have here is a living autopsy. Instead of waiting for the patient to die and then determining the cause of death, medical doctors operated, found a cause of sure death, and arrested it. The record discloses direct evidence of *620a stressful job. The record also discloses opinion evidence by a doctor that stress could have been a precipitating factor in the deterioration of claimant’s heart. Given these facts, even though other medical evidence is contradictory, the present case falls within the “any evidence” rule, and the “natural inference” discussed in Southwire Co. v. Cato, 250 Ga. 895, supra, is not reached or relied upon. Any other approach would put this court in the untenable position of weighing evidence in the guise of semantic criticism of medical opinion in each heart-related workers’ compensation case. Accordingly, we must affirm the judgment.
Decided March 12, 1984 — Rehearing denied April 2, 1984 — Michael D. Usry, John T. Woodall, Marvin W. McGahee, for appellants. Jack J. Helms, Thomas C. Chambers III, for appellee.Judgment affirmed.
Deen, P. J., Banke, Carley, and Pope, JJ., concur. Quillian, P. J., Shulman, P. J., Birdsong, and Sognier, JJ., dissent.