Dr. Dennis McCullough, a pioneer of the “slow medicine” movement, which advocates palliative care over invasive regimens for older patients suffering from the inevitable and irreversible decline of aging, died on Friday in Bar Harbor, Me. He was 72.

The cause was a heart attack, his wife, the poet Pamela Harrison, said.

Dr. McCullough, who lived in Norwich, Vt., had gone to Maine to address community nurses in a conference about slow medicine, a protocol that, dying suddenly and relatively young, he never had the opportunity to apply to himself.

Slow medicine, which is akin to palliative and hospice care, has been increasingly available in nursing homes.

Dr. McCullough’s involvement in the movement was inspired by a medical ordeal he endured, and then reinforced six years later by his mother’s lingering debility before her death.