Relationship of Echocardiographic Dyssynchrony to Long-Term Survival After Cardiac Resynchronization Therapy

• Published in: Circulation (New York, N.Y.) N.Y.), 2010-11, Vol.122 (19), p.1910-1918
• Main Authors: GORCSAN, John, OYENUGA, Olusegun, HABIB, Phillip J, TANAKA, Hidekazu, ADELSTEIN, Evan C, HARA, Hideyuki, MCNAMARA, Dennis M, SABA, Samir
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Blood and lymphatic vessels; Blood. Blood coagulation. Reticuloendothelial system; Cardiac Pacing, Artificial - methods; Cardiac Resynchronization Therapy - methods; Cardiac Resynchronization Therapy - mortality; Cardiology. Vascular system; Disease-Free Survival; Diseases of the peripheral vessels. Diseases of the vena cava. Miscellaneous; Echocardiography - methods; Female; Heart Failure - mortality; Heart Failure - physiopathology; Heart Failure - therapy; Heart Rate - physiology; Humans; Longitudinal Studies; Male; Medical sciences; Mitral Valve Insufficiency - physiopathology; Mitral Valve Insufficiency - therapy; Observer Variation; Pharmacology. Drug treatments; Probability; Prospective Studies; Stroke Volume - physiology; Survival Rate; Survivors
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/circulationaha.110.954768

The ability of echocardiographic dyssynchrony to predict response to cardiac resynchronization therapy (CRT) has been unclear. A prospective, longitudinal study was designed with predefined dyssynchrony indexes and outcome variables to test the hypothesis that baseline dyssynchrony is associated with long-term survival after CRT. We studied 229 consecutive class III to IV heart failure patients with ejection fraction ≤35 and QRS duration ≥120 milliseconds for CRT. Dyssynchrony before CRT was defined as tissue Doppler velocity opposing-wall delay ≥65 milliseconds, 12-site SD (Yu Index) ≥32 milliseconds, speckle tracking radial strain anteroseptal-to-posterior wall delay ≥130 milliseconds, or pulsed Doppler interventricular mechanical delay ≥40 milliseconds. Outcome was defined as freedom from death, heart transplantation, or left ventricular assist device implantation. Of 210 patients (89) with dyssynchrony data available, there were 62 events: 47 deaths, 9 transplantations, and 6 left ventricular assist device implantations over 4 years. Event-free survival was associated with Yu Index (P=0.003), speckle tracking radial strain (P=0.003), and interventricular mechanical delay (P=0.019). When adjusted for confounding baseline variables of ischemic origin and QRS duration, Yu Index and radial strain dyssynchrony remained independently associated with outcome (P