NPPB and stroke disorder: Similarly, in a small study involving cryptogenic stroke patients, NT-proBNP <505 pg/ml (within 24 h of stroke admission) had a negative predictive value of 98% suggesting a potential role in identifying those who may least benefit from extended cardiac monitoring.24 These statistics are very useful, particularly if considering inexpensive tests like 12 lead ECG or pulse checks for screening purposes and a biomarker with high sensitivity.