Combustor dome heat shield

A combustor dome heat shield has a heat shield panel adapted to be mounted to a combustor dome with a back face of the heat shield panel in spaced-apart facing relationship with an inner surface of the combustor dome to define an air gap between the heat shield panel and the combustor dome. Rails extend from the back face of the heat shield panel across the air gap. An anti-rotation notch is defined in at least one of the rails for receiving an anti-rotation tab of an adjacent element, such as a fuel nozzle floating collar. The rails include notch cavity rails extending on either side of the anti-rotation notch. The notch cavity rails define a notch cavity for capturing coolant air leaking through the anti-rotation notch.