Why does my car slow down whenever I reach 50 or 60 miles per hour and then shuts off?

I had the fuel filter replaced because it was leaking gas. Now when I drive and try to accelerate to 50 or 60 miles per hour, the car****** and then begins to slow down no matter how much I step on the gas pedal. It will then shut off. It takes a while to start back up. When it does start up again, it runs ok until I try to go faster.