Remove all the leaves from the artichokes, then pare the hearts. Using a sharp spoon, remove the fuzzy chokes. Cut the hearts into ¼-inch slices and drop them in water acidulated with lemon juice. Heat
Heat a large saucepan of water to boiling. Add the peas and boil 1 minute. Remove and refresh in ice water. Add the carrot julienne, if using, to the boiling water and blanch until crisp-tender, 1 to 2 minutes. Drain and refresh in ice water.
Heat a large pot of salted water to boiling for the pasta.
Meanwhile, add the pasta to the boiling water and cook until tender, about 2 minutes if the pasta is thin.
Drain the pasta and transfer to a pasta bowl. Add the sauce and quickly toss to combine. Sprinkle with Parmesan and parsley if you like. Serve hot.