on the heels of

The Running ManとなったRichardsはいよいよ逃亡を始めました。追跡者達に見つかるのではないかと常にびくびくしています。
If I'd had a gun, I would have burned him where he stood, Richards thought. Christ. Oh, Christ. And on the heels of that: Next time it won't be a purse snatcher. It'll be you.
英語では何故か "heel" が使われている慣用句が多いのですが、上の "on the heels of" はどんな意味でしょうか？
・Oxford English Dictionary: Following closely after: September frosts would be on the heels of the dog days of August.
・McGraw-Hill Dictionary of American Idioms and Phrasal Verbs: Fig. soon after something. There was a rainstorm on the heels of the windstorm. The team held a victory celebration on the heels of their winning season.
踵は前からではなく、直ぐ後ろにいると目につくので、例えば特にエスカレータで前の人の踵が目についた時にこの "on the heels of" を思い出せば覚えられそう。
ついでに今までにとりあげた "heel" の慣用句を復習します。
"heel in" (12/10/2014): to insert (cuttings, shoots, etc) into the soil before planting to keep them moist
"dig in your heels" (6/30/2014): Resist stubbornly; refuse to give in
"head over heels" (): a) At top speed; frantically b) completely; utterly (esp in the phrase head over heels in love)
"heel" 自体も踵以外に次の意味でも使われます。
"heel" (10/16/2014): a person who treats other people badly and unfairly
"heels of your hands" (2009/8/18): the part of the palm of the hand next to the wrist