The cardiac resynchronization therapy (CRT), based on correction of electro-mechanical dyssynchrony by biventricular pacing in patientswith severe chronicHF unresponsive to optimalmedical treatment and left ventricular conduction disturbances, has been developed. The determination of plasma adrenomedullin (ADM) levels before implantation could provide important additional information to reduce the high percentage (30%) of patients not responding to treatment despite the use of increasingly sophisticatedmethods for selecting candidates. The case described illustrates the importance of basal ADM plasma levels in predicting the clinical and functional improvement after treatment with CRT
