You will be given a definition of a task first, then some input of the task.
In this task, you're given a sentence and your task is to generate a simplified sentence that focuses on lexical paraphrasing from the original sentence given in the input.

the ventricular muscle twitches randomly , rather than contracting in unison , and so the ventricles fail to pump blood into the arteries and into systemic circulation.
Output:
the ventricular muscle in the heart twitches sometimes , rather than pumping steadily , and so the ventricles do not pump blood into the arteries blocking circulation.