Rambam, Laws of one who Injures or Damages, 2:7:
ז המבעית את חברו--אף על פי שחלה מן הפחד, הרי זה פטור מדיני אדם; וחייב בדיני שמיים: והוא שלא נגע בו, אלא כגון שצעק מאחוריו או נתראה לו באפילה וכיוצא בזה. וכן אם צעק באוזנו, וחירשו--פטור מדיני אדם; וחייב בדיני שמיים. אחזו, ותקע באוזנו וחירשו, או שנגע בו, ודחפו בעת שהבעיתו, או שאחז בבגדיו וכיוצא בדברים אלו--חייב בתשלומין.
If one startles his fellow, even sickening him by fright: he is exempted from man's justice, but liable to Heaven. This assumes he never touched the person; rather, he yelled from behind him or suddenly appeared out of the darkness or the like. Similarly if he yelled in his ear and that deafened him, he is exempted from man's justice but liable to Heaven's accounting. If he grabbed him and yelled in his ear, deafening him; or touched him and pushed him when surprising him, or grabbed his clothing -- he would be obligated to pay restitution.
Throughout the discussion of damages in Halacha, courts can generally only punish for actions, not words. (Giving false testimony in court is the major exception.) The Talmud's examples of liability for "embarrassment" are spitting on someone, slapping them, or tearing off their clothes in public, not saying mean things to them. The Torah absolutely prohibits vicious speech as words can absolutely cut someone down, but we say that God will deal with such a person; it's not in the hands of our justice system.
If running up and yelling BOO! at someone, giving them a heart attack, is "guilty as far as God is concerned but not in our hands to punish", I'd strongly assume that delivering shockingly bad news is in the same category. Now God only knows what I was or wasn't thinking or intending when delivering the bad news; but it's not in the place of our courts to deal with such an act.
There is also discussion of whether killing someone by metaphysical means, e.g. calling out to God to strike them dead -- is considered murder vis-a-vis our courts. (For instance, the Midrashim that Moses killed the Egyptian assailant by invoking the name of God.) See section III of Rabbi JD Bleich's "Liability for Harm Caused by Metaphysical Forces", Tradition 46:1.