Long-term changes in collagen formation expressed by serum carboxyterminal propeptide of type-I procollagen and relation to left ventricular function after acute myocardial infarction

Biomarkers of inflammation and fibrosis in young adults with history of Kawasaki disease

Background

Myocardial histology from autopsies of young adults with giant coronary artery aneurysms following Kawasaki disease (KD) shows bridging fibrosis beyond the territories supplied by the aneurysmal arteries. The etiology of this fibrosis is unknown, but persistent, low-level myocardial inflammation and microcirculatory ischemia are both possible contributing factors. To investigate the possibility of subclinical myocardial inflammation or fibrosis, we measured validated biomarkers in young adults with a remote history of KD.

Methods

We measured plasma calprotectin, galectin-3 (Gal-3), growth differentiation factor-15 (GDF-15), soluble ST2 (sST2), and serum procollagen type 1C-terminal propeptide (P1CP) in 91 otherwise healthy young adults with a remote history of KD and in 88 age-similar, healthy controls. KD subjects were stratified by coronary artery aneurysm (CAA) status and history of remote myocardial infarction (MI).

Results

After correction for multiple testing, calprotectin, Gal-3, and GDF-15 levels were significantly higher in subjects with persistent CAA (n = 26) compared with KD subjects with remodeled CAA (n = 20, p = 0.005, 0.001, 0.0036, respectively). In a multivariable regression model with CA status as the main predictor and adjusting for sex, MI history, and interval from KD onset, CA status was a significant predictor (Persistent CAA vs KD Normal CA) of calprotectin, Gal-3, GDF-15 and sST2 levels (p = 0.004, <0.001, 0.007, and 0.049, respectively).

Conclusions

These results suggest that ongoing inflammation and fibrosis may be occurring in individuals with persistent CAA. Longitudinal follow-up is needed to clarify the clinical significance of these elevated biomarker levels in this patient population that requires life-long monitoring.

Biomarkers of Inflammation and Fibrosis in Kawasaki Disease Patients Years After Initial Presentation With Low Ejection Fraction

Background Coronary artery aneurysms and myocarditis are well-recognized complications of Kawasaki disease (KD) but no systematic evaluation of the consequences of myocarditis has been performed in the subset presenting with low ejection fraction (EF). We postulated that more severe myocardial inflammation as evidenced by low EF during the acute phase could lead to late myocardial fibrosis. Methods and Results We measured the carboxyterminal propeptide of procollagen type I (PIPC), soluble suppressor of tumorigenicity 2, galectin-3 (Gal-3), growth-differentiation factor-15, and calprotectin by ELISA in late convalescent blood samples from 16 KD patients who had an EF ≤55% on their initial echocardiogram. Results were compared with samples from sex- and age-matched KD patients with initial EF >60%. In the univariate analysis, the median Gal-3 and PIPC levels in the low EF group were significantly higher than those in the normal EF group (Gal-3: low EF 6.216 versus normal EF 4.976 mg/dL P=0.038, PIPC: low EF 427.4 versus normal EF 265.2 mg/dL, P=0.01). In a multivariable analysis, there were significant differences for Gal-3 and PIPC levels between the low and normal EF groups, adjusting for age, sex, and worst z score. Conclusions Convalescent KD patients with a history of low EF during the acute illness had significantly elevated levels of Gal-3 and PIPC when compared with matched-control KD patients with normal EF. These findings raise concern for myocardial fibrosis as a potential late sequela of the more severe myocarditis experienced by a subset of KD patients during the acute phase.

Biomarkers of Myocardial Fibrosis: Revealing the Natural History of Fibrogenesis in Fabry Disease Cardiomyopathy

Background

Cardiomyopathy is a major determinant of overall Fabry disease (FD) prognosis, with the worst outcomes in patients with myocardial fibrosis. Late gadolinium enhancement is currently the gold standard for evaluation of replacement myocardial fibrosis; however, this event is irreversible, thus identification of biomarkers of earlier diffuse fibrosis is paramount.

Methods and Results

Type I collagen synthesis and degradation biomarkers (PICP [carboxyterminal propeptide of procollagen type I], ICTP [carboxyterminal telopeptide of type I collagen], and MMP1 [matrix metalloproteinase 1] and MMP2) and markers of bone synthesis and degradation were evaluated (to adjust type I collagen metabolism to bone turnover) in FD patients and controls. FD patients were grouped by cardiomyopathy severity, according to echocardiogram: (1) normal, (2) tissue Doppler abnormalities, (3) left ventricular hypertrophy. A significant increase in PICP and a significant decrease in matrix metalloproteinases were observed in FD patients; even the group with normal echocardiogram had a significant increase in PICP. We also found a significant correlation between left ventricular mass and PICP (ρ=0.378, P=0.003) and MMP1 (ρ=−0.484, P<0.001). PICP (adjusted for bone turnover) was the better predictor of left ventricular mass in multivariable regression, and its diagnostic accuracy to predict late gadolinium enhancement was also significant.

Conclusions

Collagen type I synthesis is increased in FD cardiomyopathy, even in the earlier stages of the disease, and this profibrotic state has good predictive value for and is likely to be critical to the development of overt left ventricular hypertrophy. Moreover, inhibition of enzymes involved in collagen type I cleavage also seems crucial to myocardial collagen deposition.

Fibrosis-related biomarkers and incident cardiovascular disease in older adults: the cardiovascular health study

BACKGROUND

Fibrotic changes in the heart and arteries have been implicated in a diverse range of cardiovascular diseases (CVD), but whether circulating biomarkers that reflect fibrosis are associated with CVD is unknown.

METHODS AND RESULTS

We determined the associations of 2 biomarkers of fibrosis, transforming growth factor- β (TGF-β), and procollagen type III N-terminal propeptide (PIIINP), with incident heart failure, myocardial infarction, and stroke among community-living older adults in the Cardiovascular Health Study. We measured circulating TGF-β (n=1371) and PIIINP (n=2568) from plasma samples collected in 1996 and ascertained events through 2010. Given TGF-β's pleiotropic effects on inflammation and fibrogenesis, we investigated potential effect modification by C-reactive protein in secondary analyses. After adjustment for sociodemographic, clinical, and biochemical risk factors, PIIINP was associated with total CVD (hazard ratio [HR] per SD=1.07; 95% confidence interval [CI], 1.01-1.14) and heart failure (HR per SD=1.08; CI, 1.01-1.16) but not myocardial infarction or stroke. TGF-β was not associated with any CVD outcomes in the full cohort but was associated with total CVD (HR per SD=1.16; CI, 1.02-1.31), heart failure (HR per SD=1.16; CI, 1.01-1.34), and stroke (HR per SD=1.20; CI, 1.01-1.42) among individuals with C-reactive protein above the median, 2.3 mg/L (P interaction <0.05).

CONCLUSIONS

Our findings provide large-scale, prospective evidence that circulating biomarkers of fibrosis, measured in community-living individuals late in life, are associated with CVD. Further research on whether TGF-β has a stronger fibrogenic effect in the setting of inflammation is warranted.

Usefulness of circulating biomarkers for the prediction of left ventricular remodeling after myocardial infarction

Left ventricular (LV) remodeling after myocardial infarction (MI) indicates a high risk of heart failure and death, but LV remodeling remains difficult to predict. Biomarkers may help to refine risk stratification for a more personalized medical approach. They may also shed light on the pathophysiologic processes involved. We performed a systematic review of the published evidence about the association of circulating biomarkers with LV remodeling after MI. We selected 59 publications. Overall, these studies examined 112 relations between 52 different biomarkers and LV remodeling. The biomarkers most consistently associated with LV remodeling were involved in extracellular matrix turnover or neurohormonal activation: matrix metalloproteinase-9, collagen peptides, and B-type natriuretic peptide. This review underscores the vitality of the research on LV remodeling but concludes that the ideal biomarker has not yet been identified. To reach this goal, future studies will have to be larger, have standardized imaging end points, and include replication populations to define optimal cutoffs for LV remodeling prediction. Cardiovascular magnetic resonance appears to be the best technique for LV remodeling assessment but its current availability may be a concern for recruitment for multicenter studies. Recent technologic advances will probably yield new candidate biomarkers of LV remodeling. Tests are necessary to determine whether a multimarker approach would significantly improve risk prediction.

Biomarkers: optimizing treatment guidance in heart failure

Heart failure is a frequent and life-threatening syndrome which is not only the result of myocardial injury or hemodynamic overload as commonly perceived, but appears to be the result of an interplay among genetic, neurohormonal, inflammatory, and biochemical factors, collectively referred to as biomarkers. Biomarkers can become risk factors in case their therapeutic modification results in an improvement of clinical outcomes. Among those markers identified in patients with heart failure, a number appears to have direct clinical relevance in aiding diagnosis, risk stratification, monitoring therapy, and treating to targets in order to improve clinical outcomes. These include brain natriuretic peptides (e.g., BNP, NT-proBNP), inflammatory markers (e.g., hsCRP), neurohormones (e.g., aldosterone), cardiorenal markers (e.g., cycstatin C), and novel markers (e.g., galectin-3). While their utility to indicate risk is mostly well established, there are less data to establish that a treatment using biomarkers as a guidance results in better outcomes than a more generalized intensified treatment of patients with heart failure. Future directions may involve larger platforms that facilitate to simultaneously analyze hundreds of biomarkers and may help to tailor heart failure therapy on a single patient basis, considering the specific pathogenesis and prognosis. Also from a therapeutic perspective there are data that a single intervention such as aldosterone blockade may affect multiple biomarkers at the same time. Taken together the data indicate that biomarkers are evolving into a valuable addendum to the diagnostic and therapeutic armamentarium.

Myocardial fibrosis as an early manifestation of hypertrophic cardiomyopathy

BACKGROUND

Myocardial fibrosis is a hallmark of hypertrophic cardiomyopathy and a proposed substrate for arrhythmias and heart failure. In animal models, profibrotic genetic pathways are activated early, before hypertrophic remodeling. Data showing early profibrotic responses to sarcomere-gene mutations in patients with hypertrophic cardiomyopathy are lacking.

METHODS

We used echocardiography, cardiac magnetic resonance imaging (MRI), and serum biomarkers of collagen metabolism, hemodynamic stress, and myocardial injury to evaluate subjects with hypertrophic cardiomyopathy and a confirmed genotype.

RESULTS

The study involved 38 subjects with pathogenic sarcomere mutations and overt hypertrophic cardiomyopathy, 39 subjects with mutations but no left ventricular hypertrophy, and 30 controls who did not have mutations. Levels of serum C-terminal propeptide of type I procollagen (PICP) were significantly higher in mutation carriers without left ventricular hypertrophy and in subjects with overt hypertrophic cardiomyopathy than in controls (31% and 69% higher, respectively; P<0.001). The ratio of PICP to C-terminal telopeptide of type I collagen was increased only in subjects with overt hypertrophic cardiomyopathy, suggesting that collagen synthesis exceeds degradation. Cardiac MRI studies showed late gadolinium enhancement, indicating myocardial fibrosis, in 71% of subjects with overt hypertrophic cardiomyopathy but in none of the mutation carriers without left ventricular hypertrophy.

CONCLUSIONS

Elevated levels of serum PICP indicated increased myocardial collagen synthesis in sarcomere-mutation carriers without overt disease. This profibrotic state preceded the development of left ventricular hypertrophy or fibrosis visible on MRI. (Funded by the National Institutes of Health and others.)

Effect of aldosterone antagonism on exercise tolerance, Doppler diastolic function, and quality of life in older women with diastolic heart failure

Optimal therapy for diastolic heart failure (DHF), the most common form of heart failure in older persons, is unclear. To determine the effect of aldosterone antagonism in DHF, the authors conducted an open-label preliminary trial of spironolactone 25 mg/d in 11 women with DHF. Cardiopulmonary exercise testing, Doppler echocardiography, and a quality-of-life survey were administered at baseline and after 4 months. Peak exercise VO(2) increased by 8.3% (P=.001), the ratio of Doppler diastolic early filling velocity to mitral annulus velocity decreased by 25% (P=.02), quality-of-life score improved by 21% (P=.16 for trend), and median New York Heart Association class improved from class III to class II (P=.004). Findings from this preliminary study confirm the role of aldosterone in the pathophysiology of DHF and suggest that aldosterone antagonism may benefit such patients. These hypotheses are currently being tested in two separated National Institutes of Health-funded, randomized trials, the Spironolactone for Failure in the Elderly (SPIFFIE) and the Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist (TOPCAT) trials.

Vascular remodeling and extracellular matrix breakdown in the uterine spiral arteries during pregnancy

During pregnancy, trophoblasts invade and transform the maternal spiral arteries that supply blood to the placenta. Recent work has revealed that this process occurs in several stages, and details of the molecular and cellular mechanisms are beginning to emerge, including changes that precede or accompany trophoblastic colonization of the vascular media. Disruption and eventual loss of smooth muscle cells and their associated extracellular matrix are central to physiological transformation. Advances in understanding will lead to the identification of the causative factors involved in failure of remodeling in pathological pregnancies and suggest novel diagnostic and therapeutic avenues.

Propeptide of procollagen type I (PIP) and outcomes in decompensated heart failure

BACKGROUND

Changes in extracellular matrix are recognized as a contributing factor in the cardiac remodeling process. Several studies have addressed the value of turnover markers of collagen as predictors of death or new heart failure episodes. The aim of the present study was to evaluate the relationship between peripheral serum concentration of propeptide of procollagen type I (PIP) and outcomes in patients with decompensated heart failure.

METHODS

A total of 111 patients admitted to our Unit between September 2000 and May 2003 for decompensated heart failure were analyzed. Death from any cause or due to heart failure and readmission were considered primary endpoints.

RESULTS

The mean PIP concentration was 80.84+/-36.40 ng/mL. The PIP serum level was significantly higher among those patients who suffered some endpoint during follow-up (88.12+/-37.31 ng/mL vs 73.13+/-34.06 ng/mL; p=0.029). Twenty-five (22.52%) of the 111 patients died during the 21 months of follow-up, and 54 (48.6%) were readmitted with new bouts of heart failure. Using Cox proportional hazards regression analyses, serum PIP levels, systolic dysfunction, and diabetes mellitus were identified as independent predictors of death. Serum PIP levels, age, and sex were independent predictors of new heart failure episodes and readmission.

CONCLUSION

A single serum measurement of PIP seems to have prognostic value in patients with decompensated heart failure. Accordingly, patients with higher values of PIP at decompensation are at a higher risk of death or readmission during follow-up.

Changes of collagen metabolism predict the left ventricular remodeling after myocardial infarction

OBJECTIVES

To analyze the predictive value of cardiac collagen metabolism "in vivo" in patients with myocardial infarction (MI) treated with percutaneous coronary intervention (PCI).

DESIGN

Forty-five patients (age 66 +/- 8.27) underwent biochemical analysis for cardiac collagen metabolism (groups A, B and C); 30 patients with their first MI were treated with successful PCI (group A; n = 30), group B (n = 5) were MI patients with unsuccessful PCI. Group C were patients without MI (n = 10), they underwent elective diagnostic coronary angiography only. The collagen metabolism was analyzed in acute and subacute MI phases by using serum blood markers: the carboxy-terminal propeptide of type I procollagen (PICP), amino-terminal propeptide of type III procollagen (PIIINP) and carboxy-terminal telopeptide of type I collagen (ICTP). Furthermore, the ejection fraction (EF) and left ventricular end-diastolic volume maximal changes in the course of 6 months were measured by echocardiography.

RESULTS

A significant increase of both PICP and PIIINP on day 4 following MI was detected. Furthermore, PICP and PIIINP level assessed on the 30th day was significantly higher in the PCI unsuccessful group versus successful group. PICP level on day 4 above 110 microg/l and PIIINP level above 4 microg/l was significantly often found in the subgroup of patients with the EF improvement less than 10% or worsening and with significant left ventricular dilatation during 6 months follow-up. Cardiac catheterization itself does not affect collagen metabolism.

CONCLUSION

We concluded that collagen metabolism markers enable to study in vivo the MI healing and to predict left ventricular functional and volume changes.

Circulating biomarkers of extracellular matrix remodeling and risk of atherosclerotic events

PURPOSE OF REVIEW

Disturbances of the synthesis and breakdown of the extracellular matrix of arterial walls have emerged as key features of the atherosclerotic process. Altered levels of circulating extracellular matrix markers have frequently been observed in relation to manifestations of atherosclerotic disease and its risk factors.

RECENT FINDINGS

Research has been focused on the matrix-degrading metalloproteinases, their tissue inhibitors, and procollagen peptides. The most promising matrix metalloproteinase is matrix metalloproteinase-9, which has been observed to predict rapid coronary artery narrowing, ischemic heart disease incidence, abdominal aortic aneurysm expansion, worse outcome in stroke patients, and cardiovascular death. The use of tissue inhibitors of metalloproteinases for prognostication is uncertain thus far. The procollagen marker with most prognostic potential is the marker for type III collagen turnover rate, the N-terminal propeptide PIIINP, higher levels of which predict an adverse outcome after a myocardial infarction and in chronic heart failure, and portend abdominal aortic aneurysm expansion and risk of rupture. Also, the marker for type I collagen synthesis, the C-terminal propeptide PICP, predicts adverse outcomes following myocardial infarction and in chronic heart failure. Extracellular matrix remodeling is also a promising therapeutic target, being favorably affected by several conventional cardiovascular drugs and select dietary interventions. Synthetic matrix metalloproteinase inhibitors are also under development.

SUMMARY

Circulating matrix markers have emerged as candidate biomarkers for predicting risk of subsequent atherosclerotic events. Future large longitudinal observational and intervention studies will determine the role of matrix biomarkers in diagnosis and prognostication, and as targets for intervention in cardiovascular diseases.

Influence of Primary Coronary Intervention on Myocardial Collagen Metabolism and Left Ventricle Remodeling Predicted by Collagen Metabolism Markers

The aims of the present study were to analyze cardiac collagen metabolism changes in vivo during acute and nonacute phases of ST elevation myocardial infarction (STEMI) in patients who were treated with primary coronary intervention (PCI) only, and to determine the predictive significance of collagen I and III synthesis markers (PICP, PIIINP) as well as the collagen I degradation marker (ICTP) on left ventricular function and volume changes after STEMI. Serum levels of the carboxy-terminal propeptide of type I procollagen (PICP) and amino-terminal propeptide of type III procollagen (PIIINP) assessed on the 30th day and the carboxyterminal telopeptide located at the C end of collagen type I (ICTP) assessed on the 7th day after STEMI were significantly higher (P = 0.01, P = 0.019, P = 0.04, respectively) in the PCI unsuccessful group than in the PCI successful group. These findings support the theory that early and successful PCI not only limits the amount of muscle necrosis but also protects cardiac collagen from ischemia-related injury. PICP and PIIINP levels assessed on the fourth day after acute STEMI enables us to predict the development of left ventricular function (EF) and end-diastolic volume changes over the course of 6 months, irrespective of the initial EF or revascularization success.

Impact of early changes in left ventricular filling pattern on long-term outcome after acute myocardial infarction

BACKGROUND

In patients with heart failure due to chronic ischemic heart disease improvement of diastolic function indicates improved survival and a reduced morbidity, but whether this is also the case after acute myocardial infarction is not known.

METHODS

To assess the prognostic importance of changes in left ventricular filling pattern, assessed with mitral deceleration time and colour M-mode flow propagation velocity, on cardiac death and readmission due to heart failure serial Doppler echocardiography was carried out in 103 patients with a first myocardial infarction. Based on echocardiography on hospital admission and after 1 month, patients were divided into three groups: group A (n=29) comprised patients with normal filling at either examination, group B (n=29) comprised patients with improvement of initially abnormal filling, and group C (n=45) patients with deterioration or no change of an abnormal filling pattern.

RESULTS

One-year survival free of cardiac death or hospitalisation for heart failure was 97% in group A, 86% in group B and 64% in group C (P<0.0001). In Cox analysis persistence of abnormal filling or deterioration of left ventricular filling was still a predictor of the combined endpoint (risk ratio 4.4, 95% CI 1.8-12.0, P=0.003) after adjustment of LV filling on admission, left ventricular systolic function and clinical variables. Serial analyses of left ventricular systolic function demonstrated a significant improvement after 1 year in ejection fraction in groups A and B, whereas ejection fraction remained unchanged in group C.

CONCLUSION

Patients with a persistently abnormal or a deterioration of left ventricular filling pattern as opposed to improved or normal filling are at increased risk of cardiac death and readmission due to heart failure after acute myocardial infarction.