Temporarily disable hotkeys

I am working on a Sharepoint hosted app, and reassigning some of the keys and key combinations to my custom functions. Here's the fragment of my JavaScript code that does the reassignments:

        containerElement = $("#myDiv").length;

        if (containerElement) {

            // handle alt key combinations
            if (e.altKey) {
                e.preventDefault();

                if (window.event) {
                    keycode = window.event.keyCode;
                } else if (e) {
                    keycode = e.which;
                }

                // copy the current window object event
                var e = e || window.event;

                /* ALT-V */
                if (keycode == 86 && e.altKey) {
                    var pMode = $("#PageMode").val();

                    if (pMode === "Edit") {
                        alert("in edit");
                    } else {
                        alert("NOT in edit");
                    }

                }
            }
        }

I thought I was catching the whole ALT-A combination but after the alert popup is closed the browser is opening the ribbon's drop down menu for 'View'. Is there a method either programmatically or by some policy etc. to temporarily disable the hotkeys/shortcuts that Sharepoint have assigned to the keys that I want to use, or even maybe all of them?

Any idea is appreciated