Final answer:
Duloxetine is the preferred treatment for painful diabetic neuropathy in a 65-year-old male with a cardiac history due to its safer cardiac profile compared to the other listed medications.
Step-by-step explanation:
The treatment of choice for painful diabetic neuropathy in a 65-year-old male with a cardiac history would be Duloxetine. This medication is a serotonin-norepinephrine reuptake inhibitor (SNRI) that is often prescribed for diabetic neuropathy and has a relatively safer profile for patients with cardiac conditions compared to other options like Amitriptyline, which is a tricyclic antidepressant with potential cardiac side effects. Unlike Pregabalin and Gabapentin, which are anticonvulsants that may also be used for neuropathic pain, Duloxetine is considered to have a better safety profile in the presence of cardiac conditions. Therefore, among the listed options, Duloxetine (option c) is the preferred choice.