September 1, 2008Open Access
View Full PaperMyocardial Collagen Metabolism in Failing Hearts Before and During Cardiac Resynchronization Therapy
Key Result
Cardiac resynchronization therapy responders demonstrated a significant increase in serum PINP (from 32.9 to 46.7 microg/L; p<0.001) over 6 months, indicating increased collagen synthesis.
Study Design
Type
Observational (n=64)
Structured PICO
Does cardiac resynchronization therapy alter myocardial collagen metabolism in patients with heart failure?
P
Population
64 patients with heart failure
I
Intervention
Cardiac resynchronization therapy (CRT) for 6 months
C
Comparator
Baseline values (before CRT) and comparison between CRT responders (>10% reduction in LV end-systolic volume) and non-responders
O
Outcome
Changes in serum concentrations of aminoterminal propeptides of type I and type III collagen (PINP and PIIINP) and carboxyterminal telopeptide of type I collagen (ICTP) at 6 monthssurrogate
Reverse left ventricular remodeling following CRT in heart failure patients is associated with an increase in systemic markers of collagen synthesis over 6 months.
Main Result
p-value: p=<0.001
Abstract
BACKGROUND: In patients with heart failure cardiac resynchronization therapy (CRT) leads to reverse ventricular remodelling. AIM: To evaluate whether myocardial collagen metabolism in patients with heart failure is implicated in adverse ventricular remodelling and response to CRT. METHODS: Collagen synthesis and degradation were assessed from the concentrations of aminoterminal propeptides of type I and type III collagen (PINP and PIIINP) and carboxyterminal telopeptide of type I collagen (ICTP), respectively, in serum of 64 patients with heart failure before and after 6 months of CRT. Forty-six patients (72%) showed a > 10% reduction in LV end-systolic volume at follow-up and were classified as responders to CRT, the other 18 patients (28%) were classified as non-responders. RESULTS: Responders demonstrated a mean (+/-SEM) increase of serum PINP and PIIINP during follow-up, from 32.9+/-2.2 to 46.7+/-4.0 microg/L (p < 0.001) and from 4.59+/-0.24 to 5.13+/-0.36 microg/L (p < 0.05), respectively. In non-responders, serum PINP and PIIINP remained unchanged during follow-up. At baseline, responders had significantly lower serum PINP than non-responders (32.9+/-2.2 vs. 41.8+/-4.3 microg/L; p < 0.05). ICTP levels of responders at baseline tended to be higher than in non-responders (3.54+/-0.56 vs. 2.08+/-0.37 microg/L, p = ns), and in both groups ICTP levels did not change upon CRT. CONCLUSION: Reverse LV remodelling following CRT is associated with increased collagen synthesis rate in the first 6 months of follow-up.