Maxim Avanesov MD, Presenter: Nothing to Disclose

Monica Patten, Abstract Co-Author: Nothing to Disclose

Julia Munch, Abstract Co-Author: Nothing to Disclose

Peter Bannas MD, Abstract Co-Author: Nothing to Disclose

Dennis Saring, Abstract Co-Author: Nothing to Disclose

Enver Guner Tahir MD, Abstract Co-Author: Nothing to Disclose

Gerhard B. Adam MD, Abstract Co-Author: Nothing to Disclose

Gunnar Lund MD, Abstract Co-Author: Nothing to Disclose

Myocardial fibrosis is associated with abnormal cardiac remodeling and a poorer prognosis in patients with hypertrophic cardiomyopathy (HCM). We aimed to quantify myocardial fibrosis in patients with HCM by Late Gadolinium Enhancement MRI (LGE-MRI) and evaluate its correlation with serum MMP9, a marker of myocardial fibrosis.

LGE-MRI was performed in 51 patients (54.9±14.2 years) with HCM by use of a 1.5 Tesla scanner (Achieva, Philips). The extent of fibrosis was measured by the HeAT software in percent of total myocardium on inversion-recovery images after injection of 0.2ml/kg gadolinium and compared with serum MMP9 levels. A serum MMP9 level of > 46 ng/ml was regarded as increased. This cutoff was defined as >2 standard deviations above the mean MMP9 value of 26.3 ± 9.78ng/ml obtained from 8 healthy control patients. A myocardial signal intensity >2 standard deviations above remote myocardium was regarded as LGE which was quantified in % LV area.

80,4% of all patients with HCM (41/51) showed a mean LGE of 13.3±10.3% of LV area on MR images that significantly correlated with the serum MMP9 (R2=0.397, Spearman’s ρ= 0.63, p<0.001). In all patients, the mean MMP9 level was 54.4±35.2ng/ml. The remaining 10 patients without LGE revealed a mean MMP9 level of 29.6 ± 14.2ng/ml that was significantly lower compared to the 41 patients with LGE and levels of 59.8 ± 36.2ng/ml, p =0.01. 2 of the 10 patients (20%) without LGE had increased MMP9 levels.

The extent of LGE significantly correlated with the serum fibrosis marker MMP9, underlying its value as indicator of myocardial fibrosis and poor outcome of patients with HCM. No patient had increased fibrosis on LGE-CMR and normal MMP9, so that an increased MMP9 makes myocardial fibroses visible by LGE probable. 2 patients with a mismatch of LGE and MMP9 levels (no LGE, increased MMP9) might have a diffuse fibrosis that is not detectable by standard LGE-CMR.

In patients with HCM the size of LGE correlates well with the serum myocardial fibrosis marker MMP9, so that increased MMP9 levels may predict the detection of LGE as well as poor clinical outcome.

Avanesov, M, Patten, M, Munch, J, Bannas, P, Saring, D, Tahir, E, Adam, G, Lund, G, Quantification of Late Gadolinium Enhancement in Patients with Hypertrophic Cardiomyopathy in Correlation with Serum MMP9 as an Indicator of Myocardial Fibrosis.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14009409.html