Characteristics and long-term outcome of echocardiographic super-responders to cardiac resynchronisation therapy: ‘real world’ experience from a single tertiary care centre

BackgroundThe individual benefit from cardiac resynchronisation therapy (CRT) varies largely among patients.AimsTo compare different definitions of echocardiographic super-response to CRT regarding their ability to predict the incidence of adverse events.MethodsThree definitions of super-response to CRT were evaluated in 110 consecutive patients with CRT implantation: (1) an absolute increase in ejection fraction of ≥10%; (2) a decrease in left ventricular end-systolic volume of ≥30%; and (3) a decrease in left ventricular end-diastolic volume of ≥20%. The primary endpoint was a combination of time to death, heart transplantation, ventricular assist device implantation and hospitalisation for heart failure. Secondary endpoints included time to first appropriate implantable cardioverter defibrillator (ICD) discharge during follow-up.ResultsAll three definitions of super-response were highly predictive of a reduced risk for reaching the primary combined endpoint (3-year estimators: 64%±7% vs 82%±7% for ejection fraction ≥10%; 63%±8% vs 92%±5% for end-systolic volume ≥30%; and 62%±8% vs 94%±4% for end-diastolic volume ≥20%; all p