I'm not an expert but I have some information that should be shared with you mate
so don't worry, even if the engine is affected, there's still a solution, (you can machine/overhaul the engine, to equalize the inner walls of the cylinders (and get rid of the wears which resulted from poor lubrication inside) and install new fitting pistons and valves or even buy a new engine) but as judderbar please don't do anything till you diagnose the problem first.
If you had a diagnosis done for you, and the problem you stated is confirmed and also the solution / fix is confirmed as either to get a new engine or overhaul your current engine, let me clarify the differences for you mate, first of all the price of a new engine of the same type as your current one, and the price of work / machining that will be done on your current affected engine, secondly, the performance / operation of your vehicle afterwards, the new engine replacement should be quiet the same as your current engine (sister engine from similar fiat car, same specs, a twin one) for same operation and performance matching, you MUST be sure / aware of that new engine, it must be a HEALTHY engine. The engine replacement simply should provide you with the same performance / experience as the older engine or at least not so different. Now for the second choice of "machining" the engine, as we said before, the pricing should be considered, secondly, the good news is that the performance here will be much increased to better (increase in torque and power) since machining the engine will create bigger cylinders (volume is increased) than before machining, so you will have a bigger combustion chamber for more combustion of air & fuel mixture, but the downside maybe will be the price of this operation this task is huge, I mean, larger and bigger cylinders will require you to buy new larger pistons sets and valves and other engine components perhaps, so maybe a whole engine will be cheaper I think but you must ask for prices in your local country, so in case a mechanic diagnosed the current car situation, Decision is the first and most important step I think, Good Luck Mate