Inclusion criteria were EF45 % , a mitral E-wave velocity/mitral annular velocity ratio ( E/E ' ) > 15 or N-terminal pro-B-type natriuretic peptide ( NT-proBNP ) concentration > 220 pg/ml , a left ventricular end-diastolic pressure ( LVEDP ) 18 mm Hg , and time-constant of relaxation ( tau ) 50 ms. Patients were randomized to ranolazine ( n = 12 ) or placebo ( n = 8 ) .