Serum markers of collagen turnover predict future shocks in implantable cardioverter-defibrillator recipients with dilated cardiomyopathy on optimal treatment.
OBJECTIVE
We investigated prospectively whether serum markers of collagen turnover could be used as predictors for the occurrence of malignant ventricular arrhythmias in patients with nonischemic dilated cardiomyopathy (NIDC) who had received an implantable cardioverter-defibrillator (ICD) for primary prevention.


BACKGROUND
Extracellular matrix alterations in NIDC might provide electrical heterogeneity, thus potentially contributing to the occurrence of ventricular arrhythmia and subsequent sudden cardiac death (SCD).


METHODS
Serum C-terminal propeptide of collagen type-I, C-terminal telopeptide of collagen type-I, matrix metalloproteinase (MMP)-1, and tissue inhibitor of MMP-1 were measured as markers of collagen synthesis and degradation in 70 patients with mild to moderate symptomatic heart failure due to NIDC with left ventricular ejection fraction <35%, who received an ICD for primary prevention of SCD. Patients were evaluated for any appropriate ICD delivered therapy, whether shock or antitachycardia pacing, during a 1-year follow-up period.


RESULTS
Appropriate device therapies were delivered in 14 of the 70 patients during the follow-up period, with antitachycardia pacing in 2, antitachycardia pacing with shocks in 4, and shocks in 8. Pre-implantation serum concentrations of C-terminal telopeptide of collagen type-I levels were significantly higher in patients who had appropriate ICD-delivered therapy than in those who did not have any therapy (0.46 +/- 0.19 ng/ml vs. 0.19 +/- 0.07 ng/ml, p < 0.001, respectively). The same was true for baseline MMP-1 and tissue inhibitor of MMP-1 (27.7 +/- 1.6 ng/ml vs. 24.1 +/- 2.5 ng/ml, p < 0.001, and 89 +/- 14 ng/ml vs. 58 +/- 18 ng/ml, p = 0.008, respectively).


CONCLUSIONS
If the maximum benefit is to be achieved from ICD therapy in NIDC patients for the primary prevention of SCD, a more precise risk stratification is required. As extracellular matrix alterations affect the arrhythmogenic substrate in NIDC, we observed that serum markers of collagen turnover could predict arrhythmic events in ICD recipients.
Department of Cardiology, Heraklion University Hospital, Crete, Greece.
Emmanuel M
EM
Kanoupakis
Emmanuel G
EG
Manios
Eleftherios M
EM
Kallergis
Hercules E
HE
Mavrakis
Christos A
CA
Goudis
Ilias G
IG
Saloustros
Maria E
ME
Milathianaki
Gregory I
GI
Chlouverakis
Panos E
PE
Vardas
D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood*; D002311:Cardiomyopathy, Dilated / Q000097:blood* / Q000503:physiopathology / Q000628:therapy; D003094:Collagen / Q000096:biosynthesis / Q000097:blood; D024042:Collagen Type I; D016757:Death, Sudden, Cardiac / Q000517:prevention & control; D017147:Defibrillators, Implantable; D018450:Disease Progression; D004554:Electric Countershock / Q000295:instrumentation*; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000097:blood*; D008875:Middle Aged; D010446:Peptide Fragments / Q000097:blood*; D010455:Peptides; D011347:Procollagen / Q000097:blood*; D011379:Prognosis; D011474:Prosthesis Design; D012307:Risk Factors; D013318:Stroke Volume / Q000502:physiology; D016277:Ventricular Function, Left / Q000502:physiology
D015415:Biomarkers; D024042:Collagen Type I; D010446:Peptide Fragments; D010455:Peptides; D011347:Procollagen; C052929:collagen type I trimeric cross-linked peptide; C042813:procollagen type I carboxy terminal peptide; D003094:Collagen; D020781:Matrix Metalloproteinase 1