1. Bring a large pot of lightly salted water to boiling.
2. In a large skillet, simmer diced tomatoes with marinara plus the liquid from the artichoke hearts over medium-high heat. Once simmering, cook for 10 minutes or until some of the liquid has evaporated.
3. Meanwhile, cook orzo in the boiling water as directed. Drain well and transfer to a large serving bowl.
4. Stir artichoke hearts and shrimp into sauce. Simmer 5 minutes, stirring occasionally, until cooked through. Add to orzo in bowl; toss with cheese.