Cook fusilli according to instructions on package. Drain.
While fusilli are cooking, make the alfredo sauce: Add butter and cream to large saucepan. Bring to a light simmer over medium heat, stirring continually. Remove from heat, and whisk in grated parmesan, continuing to stir until cheese is melted, and sauce is smooth.
Once the sauce is ready, toss the drained fusilli lightly with the alfredo sauce, until well coated with sauce.
Plate the pasta into 4 large bowls, adding 1/4 of the tuna fillets and 1/4 of the fresh herbs to each serving.
Top with a grating of high-quality parmesan cheese, and wedge of lemon if desired. Serve immediately.