Myocardial scar characteristics based on cardiac magnetic resonance imaging is associated with ventricular tachyarrhythmia in patients with ischemic cardiomyopathy

https://doi.org/10.1016/j.ijcard.2014.08.132Get rights and content

Highlights

  • Relative peri-infarct zone is associated with ventricular arrhythmia and ICD therapy.

  • Reduced LVEF and age are associated with mortality due to refractory heart failure.

  • CMR provide additional diagnostic value in risk stratification for SCD.

Abstract

Objectives

We hypothesized that myocardial scar characterization using cardiac magnetic resonance imaging (CMR) may be associated with the occurrence of ventricular tachyarrhythmia (VT), appropriate implantable cardioverter-defibrillator (ICD) therapy and mortality.

Background

Since a minority of patients with prophylactic ICD implantation receive appropriate ICD therapy, there is a need for more effective risk stratification for primary prevention in patients with ischemic cardiomyopathy.

Methods and results

In 99 patients with ischemic cardiomyopathy, CMR was performed prior to ICD implantation. We assessed if CMR indices (cardiac mass, LVEF) and CMR scar characteristics (infarct core mass, peri-infarction mass and the ratio's between left ventricular mass, infarct core mass and peri-infarction mass) were associated with outcome. The primary endpoint was sustained VT and/or appropriate ICD therapy. The secondary endpoint was all-cause mortality. During a median follow-up of 5.4 years (IQR 4.5–6.6 years), 34 patients reached the primary end-point (17 appropriate ICD shocks) and 26 patients died. In multivariable Cox regression analysis, peri-infarction to core-infarction ratio (HR 2.01, 95%CI: 1.17–3.44, p = 0.01) was independently and significantly associated with the primary endpoint, whereas NYHA-class and lower LVEF were not. Conversely, age (HR 1.06, 95% CI: 1.01–1.12, p = 0.02) and lower LVEF (HR 0.95, 95% CI: 0.91–1.00, p = 0.04) were independently associated with all-cause mortality, mainly due to heart failure.

Conclusion

A relatively large peri-infarction mass is associated with sustained VT and/or appropriate ICD therapy, whereas age and lower LVEF are associated with mortality. CMR based tissue characterization could aid in the prediction of specific outcome measures and in clinical decision making.

Introduction

Sudden cardiac death (SCD) is a leading cause of death in Western society [1]. Patients with reduced left ventricular ejection fraction (LVEF) (< 35%) after myocardial infarction are known to be at increased risk of SCD. In multiple randomized, controlled trials, with inclusion mainly based on LVEF, the use of an Implantable Cardioverter Defibrillator (ICD) reduced mortality [2], [3], [4], [5]. Current guidelines therefore use LVEF as the primary indicator for prophylactic ICD implantation after myocardial infarction. However, only 35% of the patients with prophylactic ICD implantation receive appropriate ICD therapy. Therefore, the use of LVEF as an indicator for ICD implantation is far from ideal [2], [6], [7]. Furthermore, an increased risk of heart failure has been reported due to unnecessary ventricular pacing [6]. There is an obvious need for more effective risk stratification for primary prevention in patients with ischemic cardiomyopathy. Cardiac magnetic resonance imaging (CMR) with late gadolinium enhanced contrast (LGE) can be used to detect myocardial scar size and heterogeneity [8], [9], [10]. As myocardial scar is an important substrate for developing ventricular tachyarrhythmia (VT) in ischemic cardiomyopathy, CMR might be useful in the prediction of future VT [11], [12], [13], [14], [15], [16], [17]. Although scar characteristics assessed by CMR are promising with regard to prediction of VT in patients with ischemic cardiomyopathy, evidence is conflicting and published papers are hampered by varying methods, limited patient and outcome numbers. Therefore, we examined in this study the potential role of multiple myocardial scar characteristics measured by CMR in predicting sustained VT and/or appropriate ICD therapy in a relatively large unselected group of patients with ischemic cardiomyopathy with long follow-up.

Section snippets

Study population

This is a single centre prospective observational study to assess the additional value of CMR characteristics in determining which patients with decreased LVEF, due to coronary artery disease, are at risk for developing life threatening VT and therefore will have benefit from ICD implantation. Patients were recruited in a single, tertiary teaching hospital in the Netherlands (Isala Klinieken, Zwolle, The Netherlands). Inclusion period was from March 2004 until November 2010. The study

Results

Ninety-nine patients were included. CMR quality was rated as ‘excellent’ in 11 (11.1%) and ‘good’ in 83 (83.8%) and ‘poor’ in 5 patients (5.1%). Patients with poor CMR quality were excluded from the study. Fig. 2 shows the inclusion and follow-up scheme. Median follow-up was 5.4 years (IQR, 4.5–6.6 years). The primary endpoint (sustained VT, and/or appropriate ICD therapy) occurred in 34 of the 94 (36.2%) patients. The secondary endpoint (all-cause mortality) occurred in 26 of the 94 (27.7%)

Discussion

The key finding of this study is the significant association of the ratio of peri-infarction to core infarction based on CMR with incident VT and appropriate ICD therapy. Reduced LVEF and age are associated with all-cause mortality. This is, to our knowledge, the first study describing the potential predictive value of the ratio of peri-infarction to core infarction mass, in terms of future VT and appropriate ICD therapy. Our study consisted of 94 patients with a median follow-up of more than 5 

Conclusion

This study shows that CMR based indices and scar heterogeneity, provides additional information regarding future VT risk and all-cause mortality, in patients with ischemic cardiomyopathy undergoing prophylactic ICD implantation. Age and reduced LVEF are associated with all-cause mortality, whereas a relatively large peri-infarction mass is associated with sustained VT and appropriate ICD therapy.

Online graph I. Cumulative incidence plots

Cumulative incidence plots of VT and/or appropriate shock (A) with death (B) as competing event demonstrates a higher risk of ventricular tachycardia and appropriate shock among patients with a higher peri-infarction to core-infarction ratio P = 0.03 between the first tertile (0.60) and third tertile (0.80) for the ratio peri-infarct mass/ infarct core mass.

The following are the Supplementary data related to this article.

Conflict of interest disclosures

The authors have no conflicts of interest.

Acknowledgements

The authors thank Vera Derks for her skillful assistance and Petra Koopmans for her assistance during statistics analysis.

References (38)

  • M.S. Ahn et al.

    Prognostic implications of fragmented QRS and its relationship with delayed contrast-enhanced cardiovascular magnetic resonance imaging in patients with non-ischemic dilated cardiomyopathy

    Int J Cardiol

    (2013)
  • E. Bikiri et al.

    Dobutamine stress cardiac magnetic resonance versus echocardiography for the assessment of outcome in patients with suspected or known coronary artery disease. Are the two imaging modalities comparable?

    Int J Cardiol

    (2014)
  • E. Koutalas et al.

    Sudden cardiac death in non-ischemic dilated cardiomyopathy: a critical appraisal of existing and potential risk stratification tools

    Int J Cardiol

    (2013)
  • K.H. Haugaa et al.

    Mechanical dispersion assessed by myocardial strain in patients after myocardial infarction for risk prediction of ventricular arrhythmia

    JACC Cardiovasc Imaging

    (2010)
  • J.P. Daubert et al.

    Predictive value of ventricular arrhythmia inducibility for subsequent ventricular tachycardia or ventricular fibrillation in Multicenter Automatic Defibrillator Implantation Trial (MADIT) II patients

    J Am Coll Cardiol

    (2006)
  • A. Welinder et al.

    Importance of standardized assessment of late gadolinium enhancement for quantification of infarct size by cardiac magnetic resonance: implications for comparison with electrocardiogram

    J Electrocardiol

    (2011)
  • D.P. Zipes et al.

    ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: a report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death) developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society

    Europace

    (2006)
  • G.H. Bardy et al.

    Amiodarone or an implantable cardioverter-defibrillator for congestive heart failure

    N Engl J Med

    (2005)
  • A.J. Moss et al.

    Prophylactic implantation of a defibrillator in patients with myocardial infarction and reduced ejection fraction

    N Engl J Med

    (2002)
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