The A in PUFA is just acid, as in polyunsaturated fatty acid. Manufacturers add potent antioxidants(ie vitamin e) to fragile oils to extend their shelf life. Fat fragility with cooking is one thing, but inside our bodies is more important. The strongest source of oxidants is within our mitochondria. No real way to avoid that so it's better to ensure that they (cardiolipin in particular) are built from more resilient fatty acids.

As for heart disease, atherosclerosis only happens with oxidized or glycated cholesterol. Of course the 'medical establishment' focuses on lowering cholesterol when people should instead build their cholesterol out of more robust fatty acids (Saturated or mono) instead of PUFA. Macrophages and resulting foam cells don't even react to native, non-oxidized or glycated cholesterol. The statin drug industry has earned $1 trillion for them over the last several decades. Completely unnecessary, and harmful to normal hormone production which requires cholesterol.

Olive oil is high in monounsaturated fatty acids are beneficial. Even when the single double bond is broken it goes into two shorter chain saturated fats, not the poisonous junk that pufas degrade into. Many off-the-shelf olive or avocado oils are spiked with cheap soybean oil (high pufa) so I just use butter (or ghee), coconut oil and tallow.