PMID- 14727967
OWN - NLM
STAT- MEDLINE
DCOM- 20040414
LR  - 20181025
IS  - 1175-3277 (Print)
IS  - 1175-3277 (Linking)
VI  - 2
IP  - 4
DP  - 2002
TI  - Cardiac resynchronization therapy in patients with chronic heart failure: 
      pathophysiology and current experience.
PG  - 219-26
AB  - Congestive heart failure afflicts 2 to 4 million people in the US and nearly 15 
      million people worldwide. Accepted goals of heart failure treatment include: 
      improvement of symptoms;prevention of disease progression; and reduction in 
      morbidity and mortality. Complex pharmacological therapies achieve these goals, 
      but not in all patients with heart failure. Cardiac resynchronization therapy 
      (CRT) represents a new therapeutic approach in patients with chronic heart 
      failure. CRT is only applicable to a subgroup of patients with ventricular 
      conduction system delay, characterized by prolonged QRS duration. Bundle branch 
      block impacts 20 to 30% of patients with New York Heart Association (NYHA) 
      functional class III-IV heart failure and consists predominantly of left bundle 
      branch block. When left ventricular (LV) conduction delay is superimposed upon 
      ventricular dysfunction, it appears to be a marker of disease severity. These 
      conduction abnormalities have deleterious effects both on systolic function and 
      LV filling, and they can induce or enhance mitral functional regurgitation. CRT 
      attempts to correct the deleterious effect of dysynchrony by increasing LV 
      filling time, decreasing septal dyskinesis and reducing mitral regurgitation. 
      Several observational studies and randomized, controlled trials have shown the 
      benefit of CRT in a subgroup of patients with heart failure, with conduction 
      delays. Improvements were found in the mean distance walked in 6 minutes, quality 
      of life (QOL), NYHA functional class, in peak oxygen uptake (V-dot(2)), total 
      exercise time, reduction of hospitalization, LV function and reduction of the LV 
      end-diastolic diameter. These studies support the therapeutic value of 
      ventricular resynchronization in patients with severe heart failure, who have 
      intraventricular conduction delay but who do not have a standard indication for 
      the implantation of a pacemaker. In respect to these study results, possible 
      indications for a biventricular pacing device at this time are as follows: NYHA 
      functional class III, LV ejection fraction <35%, sinus rhythm, QRS duration >150 
      msec and drug refractory despite individual optimal heart failure therapy. CRT 
      significantly improved symptoms, exercise tolerance and QOL in most patients. 
      However, further studies are needed to assess long-term clinical effects and 
      prognosis, as well as economic benefit of this therapeutic approach.
FAU - Seidl, Karlheinz
AU  - Seidl K
AD  - Department of Cardiology, Heart Centre, Ludwigshafen, Germany. seidlk@klilu.de
FAU - Rameken, Monika
AU  - Rameken M
FAU - Vater, Margit
AU  - Vater M
FAU - Senges, Jochen
AU  - Senges J
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Review
PL  - New Zealand
TA  - Am J Cardiovasc Drugs
JT  - American journal of cardiovascular drugs : drugs, devices, and other 
      interventions
JID - 100967755
SB  - IM
MH  - Cardiac Pacing, Artificial/*methods
MH  - *Defibrillators, Implantable
MH  - Heart Conduction System/physiopathology
MH  - Heart Failure/physiopathology/*therapy
MH  - Humans
MH  - Randomized Controlled Trials as Topic
MH  - Ventricular Dysfunction/physiopathology/therapy
RF  - 53
EDAT- 2004/01/20 05:00
MHDA- 2004/04/15 05:00
CRDT- 2004/01/20 05:00
PHST- 2004/01/20 05:00 [pubmed]
PHST- 2004/04/15 05:00 [medline]
PHST- 2004/01/20 05:00 [entrez]
AID - 020401 [pii]
AID - 10.2165/00129784-200202040-00001 [doi]
PST - ppublish
SO  - Am J Cardiovasc Drugs. 2002;2(4):219-26. doi: 10.2165/00129784-200202040-00001.