Combine the cream cheese and all but 1/2 cup of the crabmeat in a medium bowl. Mix until thoroughly combined. Roll into an 8-inch log and refrigerate until firmed up slightly, about 1 hour. Refrigerate the remaining 1/2 cup crabmeat until serving.
Meanwhile, combine the ketchup, horseradish, lemon juice, salt and some pepper in a medium bowl. Taste and adjust to your liking.
Place the log on a serving platter. Spoon some of the sauce over it, reserving the remaining sauce in a small bowl to serve on the side. Sprinkle the reserved 1/2 cup crabmeat on top and garnish with the chives. Rub the garlic onto one side of each slice of bread and arrange the bread on the serving platter.
Adapted from "One Dish at a Time: Delicious Recipes from My Italian-American Childhood and Beyond" by Valerie Bertinelli © Rodale 2012. Provided courtesy of Valerie Bertinelli. All rights reserved.