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  • Review Article
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Role of cardiac MRI and nuclear imaging in cardiac resynchronization therapy

Nature Reviews Cardiology volume 6, pages 759–770 (2009)Cite this article

Abstract

Cardiac resynchronization has emerged as a highly effective therapy for heart failure. However, up to 40% of patients do not benefit from this treatment. In this Review, we discuss the potential role of MRI and nuclear molecular imaging in providing additional insights into the response to cardiac resynchronization therapy. Variables with potential prognostic and therapeutic values include the evaluation of cardiac dyssynchrony, scar, cardiac sympathetic function, myocardial blood flow, myocardial glucose and oxidative metabolism. Other molecular targets to characterize apoptosis, fatty acid metabolism, angiogenesis and angiotensin-converting enzyme activity will also be described. The potential use of these techniques in identifying and measuring responses to cardiac resynchronization therapy and future areas of research will be explored.

Key Points

  • Cardiac resynchronization therapy (CRT) is standard treatment for patients with advanced heart failure, but up to 30% of patients receive no benefit and identifying those who do respond is challenging

  • Single-center studies have shown that intraventricular dyssynchrony is predictive of CRT response, which can be measured by echocardiographic, nuclear and cardiac MRI techniques

  • Echocardiography is the most widely used technique to evaluate dyssynchrony and predict CRT response but most echocardiographic markers have limited inter-observer reproducibility and have not proved consistently useful as predictors of outcome after CRT

  • Cardiac MRI and nuclear imaging might provide additional insight into CRT response through evaluation of scar, tissue viability, myocardial blood flow and metabolism, and measuring cardiac sympathetic activity

  • The choice of a given imaging modality depends on the robustness of the technique, local availability and expertise, potential for integrated assessment, radiation exposure, characteristics of the patient and contraindications

  • Further experimental and clinical studies in molecular imaging, as well as large, carefully designed, prospective trials, are needed to examine the use of promising imaging technology to identify CRT responders

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Figure 1: Tagged MRI.
Figure 2: Tissue velocity mapping by MRI.
Figure 3: Cine images of DENSE MRI.
Figure 4: Late gadolinium enhancement MRI.
Figure 5: Short axis, horizontal long axis and polar map uptake of FDG–PET and 99mTc-sestamibi–SPECT images at baseline and after CRT in a patient with severe nonischemic cardiomyopathy.
Figure 6: The septal:lateral ratio of regional left ventricular oxidative metabolism measured by 11C-acetate PET was significantly higher in simultaneous CRT, compared with atrial pacing with AAI.

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Authors and Affiliations

  1. The Department of Internal Medicine Mayo Clinic, Rochester, MN, USA

    Niti R. Aggarwal

  2. The Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA

    Bernard J. Gersh & Panithaya Chareonthaitawee

  3. Division of Cardiology at Lehigh Valley Health Network and Penn State University, Allentown, PA, USA

    Matthew W. Martinez

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Correspondence to Panithaya Chareonthaitawee.

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Aggarwal, N., Martinez, M., Gersh, B. et al. Role of cardiac MRI and nuclear imaging in cardiac resynchronization therapy. Nat Rev Cardiol 6, 759–770 (2009). https://doi.org/10.1038/nrcardio.2009.189

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