Foley, Paul W X and Chalil, Shajil and Khadjooi, Kayvan and Jordan, Paul and Smith, Russell E A and Frenneaux, Michael P and Leyva, Francisco (2010) Effects of cardiac resynchronization therapy in patients unselected for mechanical dyssynchrony. International journal of cardiology, 143 (1). pp. 51-6. ISSN 1874-1754. This article is accessible to all HEFT staff and students via NHS Evidence www.evidence.nhs.uk by using their HEFT Athens login IDsFull text not available from this repository.
Observational echocardiographic studies have suggested that pre-implant dyssynchrony is required for a response to cardiac resynchronization therapy. Some clinical guidelines on CRT have adopted dyssynchrony as a requirement prior to CRT.
To assess the effects of CRT in patients with heart failure who are unselected for mechanical dyssynchrony.
248 consecutive patients with heart failure (sinus rhythm, NYHA class III [n=171, 89%]) or IV (n=77, 31%; LVEF<or=35%, QRS>or=120 ms) underwent a clinical assessment, including NYHA class, 6-min walking distance and quality of life (Minnesota Living with Heart Failure questionnaire) before and after CRT. Clinical event variables included mortality and hospitalizations for major cardiovascular events and for heart failure.
At follow-up, NYHA class was reduced from 3.25+/-0.56 to 2.06+/-0.84 (mean+/-SD, p<0.0001). There were also improvements in 6-min walking distance (232.2+/-113.8 to 302.9+/-119.5 m) and quality of life scores (56.1+/-20.4 to 32.5+/-23.4) (both p<0.0001). Responder rate, defined as improvement by >or=1 NYHA classes or>or=25% in 6-min walking distance, was 81% (202/248 patients). Over a follow-up period of up to 7.4 years (median 720 days), the annualized total and cardiovascular mortality rates were 11.7% and 9.89%, respectively.
In patients undergoing CRT, the improvements in functional capacity and quality of life as well as the event rates expected from landmark trials are achievable by selecting patients on the basis of NYHA class, LVEF and QRS duration alone. The added value of echocardiographic measures of dyssynchrony remains questionable.
|Additional Information:||This article is accessible to all HEFT staff and students via NHS Evidence www.evidence.nhs.uk by using their HEFT Athens login IDs|
|Subjects:||WG Cardiovascular system. Cardiology|
|Divisions:||Emergency Services > Cardiology|
|Depositing User:||Sophie Rollason|
|Date Deposited:||10 Jun 2014 13:28|
|Last Modified:||10 Jun 2014 13:28|
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