Scholarly article on topic 'Effects of myocardial fibrosis and ventricular dyssynchrony on response to therapy in new-presentation idiopathic dilated cardiomyopathy: insights from cardiovascular magnetic resonance and echocardiography'

Effects of myocardial fibrosis and ventricular dyssynchrony on response to therapy in new-presentation idiopathic dilated cardiomyopathy: insights from cardiovascular magnetic resonance and echocardiography Academic research paper on "Clinical medicine"

CC BY
0
0
Share paper
OECD Field of science
Keywords
{""}

Academic research paper on topic "Effects of myocardial fibrosis and ventricular dyssynchrony on response to therapy in new-presentation idiopathic dilated cardiomyopathy: insights from cardiovascular magnetic resonance and echocardiography"

Leong et al. Journal of Cardiovascular Magnetic Resonance 2011, 13(Suppl 1):P338 http://jcmr-online.com/content/13/S1/P338

'V/ Magnetic Resonance

POSTER PRESENTATION Open Access

Effects of myocardial fibrosis and ventricular dyssynchrony on response to therapy in new-presentation idiopathic dilated cardiomyopathy: insights from cardiovascular magnetic resonance and echocardiography

Darryl P Leong1*, Adhiraj Chakrabarty2, Nicholas Shipp3, Payman Molaee3, Per Lav Madsen4, Lucas Joerg4, Thomas Sullivan5, Hugh Greville6, Stephen G Worthley3, Carmine G De Pasquale4, Prashanthan Sanders3, Joseph B Selvanayagam2

From 2011 SCMR/Euro CMR Joint Scientific Sessions Nice, France. 3-6 February 2011

Objectives

To determine whether the extent of myocardial fibrosis by late-gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR), and echocardiography ventricular dyssynchrony can independently predict response to medical therapy in patients with newly-diagnosed idiopathic dilated cardiomyopathy (DCM).

Background

Myocardial fibrosis and ventricular dyssynchrony are frequent findings in DCM. Although previous studies have reported poor prognosis with the presence of myo-cardial fibrosis in DCM, they focussed on patients with established cardiomyopathy, and did not characterise patients early in the disease course and may not have included those with significant improvement in LV function soon after diagnosis. Hence, the degree of myocardial fibrosis and ventricular dyssynchrony at initial presentation, and their role in perpetuating left ventricular (LV) dysfunction in DCM remains unclear. We hypothesised that extent of myocardial fibrosis by the LGE-CMR technique and echocardiographic ventricular dyssynchrony are independent predictors of failure of improvement in LV function in new-onset DCM.

department of Cardiovascular Medicine, Flinders MedicalCentre, Adelaide, Australia, The University of Adelaide, Adelaide, Australia, The Flinders University of South Australia, Adelaide, Australia Fulllist of author information is available at the end of the article

Bio Med Central

Methods

Patients with a new diagnosis of DCM (LV ejection fraction (EF) <45%) made within the preceding two weeks were recruited. Patients underwent LGE-CMR, echocar-diography, 6-minute-walk testing, cardiopulmonary exercise testing, and blood sampling for measurement of serum NT-pro-BNP concentration at baseline. Baseline patient characteristics were compared with a cohort of healthy volunteers. Myocardial fibrosis by LGE-CMR was identified by experienced observers blinded to patient outcome, and was quantified by planimetry for calculation of fibrosis mass. LV systolic function was reassessed after 5 months optimal medical therapy.

Results

Sixty-eight patients with DCM and 19 healthy volunteers were studied. DCM patients were studied a median 12.5 days following diagnosis. Compared to healthy controls, DCM patients exhibited poorer functional capacity, higher serum NT-pro-BNP concentration, and greater inter- and intraventricular dyssynchrony. Twenty-four percent of DCM patients exhibited LGE at diagnosis, whereas no LGE was observed amongst controls. Within DCM patients with LGE, the mean fibrosis mass was 2.2 ±1.3g. On multivariate analysis, strain dyssynchrony index, and fibrosis mass were independent predictors of change in LVEF over time (p<0.001) (Table 1). LGE-CMR conferred additive prognostic value over and above

© 2011 Leong et al; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Leong et al. Journal of Cardiovascular Magnetic Resonance 2011, 13(Suppl 1):P338 Page 2 of 2

http://jcmr-online.com/content/13/S1/P338

Table 1 Uni- and Multivariate Model of Prognostic Factors for Change in LVEF

Variable Univariate model Multivariate model

Coefficient (95% CI) p-value Coefficient (95% CI) p-value

Age -0.06 (-0.3 to 0.2) 0.8

Gender -4 (-10 to 3) 0.8

6-minute walk distance (m) 0.03 (-0.01 to 0.08) 0.3

VO2 PEAK (mL/kg/min) 0.3 (-0.7 to 1.3) 0.6

Tissue Doppler dyssynchrony index (ms) -0.07 (-0.3 to 0.2) 0.7

E/E' 0.04 (-0.2 to 0.3) 0.8

Left atrial volume (mL) -0.02 (-0.1 to 0.1) 0.8

TAPSE (cm) -1 (-10 to 7) 0.7

Interventricular mechanical delay (ms) -0.1 (-0.3 to 0.05) 0.3 0.3 (-0.06 to 0.6) 0.1

NT-pro BNP (ng/L) -1 (-2 to -0.09) 0.007 -0.2 (-2 to 1) 0.8

QRS-duration (ms) -0.14 (-0.3 to -0.02) 0.004 -0.3 (-0.7 to 0.1) 0.2

Strain dyssynchrony index (ms) -0.1 (-0.2 to -0.06) 0.04 -0.1 (-0.2 to -0.04) <0.001

Fibrosis mass (g) -7 (-11 to -3) <0.001 -7 (-11 to -4) <0.001

clinical and echo-dyssynchrony parameters for the prediction of improvement in LVEF.

Conclusions

The extent of myocardial fibrosis is a powerful predictor of a negative response to medical therapy in new-presentation DCM, and LGE-CMR may thus be an important risk-stratifying investigation in these patients. Accurate risk stratification may permit more targeted pharmacological and device therapies for patients with newly-diagnosed DCM.

Author details

department of Cardiovascular Medicine, Flinders MedicalCentre, Adelaide, Australia, The University of Adelaide, Adelaide, Australia, The Flinders University of South Australia, Adelaide, Australia. 2Department of Cardiovascular Medicine, Flinders Medical Centre, Adelaide, Australia, The Flinders University of South Australia, Adelaide, Australia. 3University of Adelaide, Adelaide, Australia, Adelaide, Australia. 4Department of Cardiovascular Medicine, Flinders Medical Centre, Adelaide, Australia, Adelaide, Australia. 5Discipline of Public Health, University of Adelaide, Adelaide, Australia. 6Department of Respiratory Medicine, RoyalAdelaide Hospital, Adelaide, Australia.

Published: 2 February 2011

doi:10.1186/1532-429X-13-S1-P338

Cite this article as: Leong et al.: Effects of myocardial fibrosis and ventricular dyssynchrony on response to therapy in new-presentation idiopathic dilated cardiomyopathy: insights from cardiovascular magnetic resonance and echocardiography. Journal of Cardiovascular Magnetic Resonance 2011 13(Suppl 1):P338.

Submit your next manuscript to BioMed Central and take full advantage of:

• Convenient online submission

• Thorough peer review

• No space constraints or color figure charges

• Immediate publication on acceptance

• Inclusion in PubMed, CAS, Scopus and Google Scholar

• Research which is freely available for redistribution

Submit your manuscript at „- ..■■ . f-f.ntn|

www.biomedcentral.com/submit