H eartsinks, in doctors’ private and profane lingo, are difficult patients who conjure dismay in the hearts of the medical professionals they come to see. So Dr Jeffrey Longford (Aden Gillett) reminds his friend and fellow GP after dealing with a “fit as a flea” hypochondriac who returns, week after week, albeit always with a slice of cake.

Jeffrey becomes something of a heartsink himself when he turns from doctor to patient after being diagnosed with terminal cancer. The real-life cases of Paul Kalanithi (in When Breath Becomes Air ) and Henry Marsh (in And Finally ) show how difficult it is for doctors to adjust to the patient role.…