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/pdf/acc-aha-2005-guideline-update-for-the-diagnosis-and-4hik65ngbe.pdf

ACC/AHA 2005 Guideline Update for the Diagnosis and Management of Chronic Heart Failure in the Adult

Background Previous studies have suggested that cardiac resynchronization achieved through atrial-synchronized biventricular pacing produces clinical benefits in patients with heart failure who have an intraventricular conduction delay. We conducted a double-blind trial to evaluate this therapeutic approach. Methods Four hundred fifty-three patients with moderate-to-severe symptoms of heart failure associated with an ejection fraction of 35 percent or less and a QRS interval of 130 msec or more were randomly assigned to a cardiac-resynchronization group (228 patients) or to a control group (225 patients) for six months, while conventional therapy for heart failure was maintained. The primary end points were the New York Heart Association functional class, quality of life, and the distance walked in six minutes. Results As compared with the control group, patients assigned to cardiac resynchronization experienced an improvement in the distance walked in six minutes (+39 vs. +10 m, P=0.005), functional clas...

Cardiac Resynchronization in Chronic Heart Failure

ACC/AHA 2005 guideline update for the diagnosis and management of chronic heart failure in the adult: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Update the 2001 Guidelines for the Evaluation and Management of Heart Failure).

Mariell Jessup, MD, FACC, FAHA, Chair [*][1]

William T. Abraham, MD, FACC, FAHA[†][2]

Donald E. Casey, MD, MPH, MBA[‡][3]

Arthur M. Feldman, MD, PhD, FACC, FAHA[§][4]

Gary S. Francis, MD, FACC, FAHA[§][4]

Theodore G. Ganiats, MD[∥][5]

Marvin A. Konstam, MD, FACC[¶][6]

Donna M.

/pdf/2009-focused-update-incorporated-into-the-acc-aha-2005-3z9lhvyqwq.pdf

2009 Focused Update Incorporated Into the ACC/AHA 2005 Guidelines for the Diagnosis and Management of Heart Failure in Adults A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines: Developed in Collaboration With the International Society for Heart and Lung Transplantation

ContextCardiac resynchronization therapy (CRT) through biventricular pacing
is an effective treatment for heart failure (HF) with a wide QRS; however,
the outcomes of patients requiring CRT and implantable cardioverter defibrillator
(ICD) therapy are unknown.ObjectiveTo examine the efficacy and safety of combined CRT and ICD therapy in
patients with New York Heart Association (NYHA) class III or IV congestive
HF despite appropriate medical management.Design, Setting, and ParticipantsRandomized, double-blind, parallel-controlled trial conducted from October
1, 1999, to August 31, 2001, of 369 patients with left ventricular ejection
fraction of 35% or less, QRS duration of 130 ms, at high risk of life-threatening
ventricular arrhythmias, and in NYHA class III (n = 328) or IV (n = 41) despite
optimized medical treatment.InterventionsOf 369 randomized patients who received devices with combined CRT and
ICD capabilities, 182 were controls (ICD activated, CRT off) and 187 were
in the CRT group (ICD activated, CRT on).Main Outcome MeasuresThe primary double-blind study end points were changes between baseline
and 6 months in quality of life, functional class, and distance covered during
a 6-minute walk. Additional outcome measures included changes in exercise
capacity, plasma neurohormones, left ventricular function, and overall HF
status. Survival, incidence of ventricular arrhythmias, and rates of hospitalization
were also compared.ResultsAt 6 months, patients assigned to CRT had a greater improvement in median
(95% confidence interval) quality of life score (–17.5 [–21 to
–14] vs –11.0 [–16 to –7], P =
.02) and functional class (–1 [–1 to –1] vs 0 [–1
to 0], P = .007) than controls but were no different
in the change in distance walked in 6 minutes (55 m [44-79] vs 53 m [43-75], P = .36). Peak oxygen consumption increased by 1.1 mL/kg
per minute (0.7-1.6) in the CRT group vs 0.1 mL/kg per minute (–0.1
to 0.8) in controls (P = .04), although treadmill
exercise duration increased by 56 seconds (30-79) in the CRT group and decreased
by 11 seconds (–55 to 12) in controls (P<.001).
No significant differences were observed in changes in left ventricular size
or function, overall HF status, survival, and rates of hospitalization. No
proarrhythmia was observed and arrhythmia termination capabilities were not
impaired.ConclusionsCardiac resynchronization improved quality of life, functional status,
and exercise capacity in patients with moderate to severe HF, a wide QRS interval,
and life-threatening arrhythmias. These improvements occurred in the context
of underlying appropriate medical management without proarrhythmia or compromised
ICD function.

https://jamanetwork.com/journals/jama/articlepdf/1108361/JOC30332.pdf

Craig Roy

Papers

Natural history of abnormal conduction and its relation to prognosis in patients with dilated cardiomyopathy

Association of reduced PR-AC interval with ventricular early potentials in dilated cardiomyopathy.