Cardiac resynchronization induces major structural and functional reverse remodeling in patients with New York Heart Association class I/II heart failure.
BACKGROUND
Cardiac resynchronization therapy (CRT) improves LV structure, function, and clinical outcomes in New York Heart Association class III/IV heart failure with prolonged QRS. It is not known whether patients with New York Heart Association class I/II systolic heart failure exhibit left ventricular (LV) reverse remodeling with CRT or whether reverse remodeling is modified by the cause of heart failure.


RESULTS
Six hundred ten patients with New York Heart Association class I/II heart failure, QRS duration > or =120 ms, LV end-diastolic dimension > or =55 mm, and LV ejection fraction < or =40% were randomized to active therapy (CRT on; n=419) or control (CRT off; n=191) for 12 months. Doppler echocardiograms were recorded at baseline, before hospital discharge, and at 6 and 12 months. When CRT was turned on initially, immediate changes occurred in LV volumes and ejection fraction; however, these changes did not correlate with the long-term changes (12 months) in LV end-systolic (r=0.11, P=0.31) or end-diastolic (r=0.10, P=0.38) volume indexes or LV ejection fraction (r=0.07, P=0.72). LV end-diastolic and end-systolic volume indexes decreased in patients with CRT turned on (both P<0.001 compared with CRT off), whereas LV ejection fraction in CRT-on patients increased (P<0.0001 compared with CRT off) from baseline through 12 months. LV mass, mitral regurgitation, and LV diastolic function did not change in either group by 12 months; however, there was a 3-fold greater reduction in LV end-diastolic and end-systolic volume indexes and a 3-fold greater increase in LV ejection fraction in patients with nonischemic causes of heart failure.


CONCLUSIONS
CRT in patients with New York Heart Association I/II resulted in major structural and functional reverse remodeling at 1 year, with the greatest changes occurring in patients with a nonischemic cause of heart failure. CRT may interrupt the natural disease progression in these patients. Clinical Trial Registration- Clinicaltrials.gov Identifier: NCT00271154.
St John Sutton
Martin
M
University of Pennsylvania Medical Center, Philadelphia, PA 19104, USA. suttonm@mail.med.upenn.edu
Ghio
Stefano
S
Plappert
Ted
T
Tavazzi
Luigi
L
Scelsi
Laura
L
Daubert
Claude
C
Abraham
William T
WT
Gold
Michael R
MR
Hassager
Christian
C
Herre
John M
JM
Linde
Cecilia
C
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000368:Aged; D047228:Angiotensin II Type 1 Receptor Blockers / Q000627:therapeutic use; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D002304:Cardiac Pacing, Artificial; D002306:Cardiac Volume; D003131:Combined Modality Therapy; D015150:Echocardiography, Doppler; D004562:Electrocardiography; D005260:Female; D054143:Heart Failure, Systolic / Q000145:classification / Q000000981:diagnostic imaging* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013318:Stroke Volume; D016896:Treatment Outcome; D020257:Ventricular Remodeling
D000319:Adrenergic beta-Antagonists; D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors