Cardiac resynchronization therapy: which device to implant?

Cardiac resynchronization therapy is now a validated treatment for patients with moderate to severe heart failure despite optimal drug treatment with left ventricular systolic dysfunction and cardiac dyssynchrony defined by wide QRS greater than 120 ms. Once an indication for cardiac resynchronization therapy has been confirmed the choice of the most appropriate device (pacemaker or intracardiac cardioverter defibrillator (ICD)) needs to be made. In heart failure patients the risk of sudden death, mainly but not always related to arrhythmic cause is high. Previous studies of primary prevention of sudden cardiac death in patients with a poor left ventricular function have shown that ICD therapy significantly reduces overall mortality and arrhythmic mortality. However patients candidates to cardiac resynchronization therapy are different from those included in the ICDs trials because they are older and have more comorbidities. The choice of the devices has to consider the potential benefit of the therapy, the comorbidities, the life expectancy but also the cost-effectiveness and the potential complications related to the device. Now, new devices provide information about the hemodynamic status of this heart failure population and thus provide an early detection of heart failure decompensation. The development of home monitoring should alert very early the physicians of the occurrence of a heart failure decompensation and thus to avoid recurrent hospitalisations for heart failure decompensation.