There are several literary devices and stylistic peculiarities in the lines spoken by Lady Macbeth:
The first one is an asyndeton, which Baldick defines as "a form of verbal compression which consists of the omission of connecting words (usually conjunctions) between clauses". Lady Macbeth omits the conjunction "and" in "Thou wouldst be great; [and] Art not without ambition". This results in a paratactic style, as in Julius Caesar's famous "Veni, vidi, vici".
There is an ellipsis of the pronoun "thou" in the second line.
The phrase "Not without [ambition]" is an example of litotes, which Baldick defines as "a figure of speech by which an affirmation made indirectly by denying its opposite, usually with an effect of understatement". Hence, we are meant to understand that Macbeth is very ambitious.
There is another asyndeton in the omission of the relative pronoun "that" in "The illness [that] should attend it". This is not unusual in Shakespeare.
Finally, since, Macbeth is not present on the stage, the speech itself is an example of apostrophe, i.e. "a rhetorical figures in which the speaker addresses a dead or absent person, or an abstraction or inanimate object" (Baldick).
Baldick, Chris: The Concise Oxford Dictionary of Literary Terms. Second edition. Oxford University Press, 2001.