GUIDE-IT is a prospective , randomized , controlled , unblinded , multicenter clinical trial designed to randomize approximately 1,100 high-risk subjects with systolic HF ( left ventricular ejection fraction40 % ) to either usual care ( optimized guideline-recommended therapy ) or a strategy of adjusting therapy with the goal of achieving and maintaining a target NT-proBNP level of < 1,000 pg/ml .