Accepted Manuscript Reply to Letter to the Editor: feature tracking cardiac magnetic resonance imaging in the assessment of left atrial function Brian D. Hoit, M.D. PII:
S0735-1097(14)01308-4
DOI:
10.1016/j.jacc.2014.02.544
Reference:
JAC 19949
To appear in:
Journal of the American College of Cardiology
Received Date: 4 February 2014 Accepted Date: 11 February 2014
Please cite this article as: Hoit BD, Reply to Letter to the Editor: feature tracking cardiac magnetic resonance imaging in the assessment of left atrial function, Journal of the American College of Cardiology (2014), doi: 10.1016/j.jacc.2014.02.544. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Reply to Letter to the Editor: feature tracking cardiac magnetic resonance imaging in the
RI PT
assessment of left atrial function
Brian D. Hoit, M.D.
M AN U
SC
Professor of Medicine, Physiology and Biophysics, Case Western Reserve University Director of Echocardiography, University Hospitals Case Medical Center
TE D
Disclosures. Dr. Hoit is a speaker for Philips Medical.
AC C
EP
Address for Reprints: Brian D Hoit Harrington Heart and Vascular Center University Hospitals Case Medical Center 11100 Euclid Avenue, Cleveland OH 44106-5038 (216) 844-3855 (216) 844-8954 (fax) [email protected]
1
ACCEPTED MANUSCRIPT
I appreciate the interest shown by Dr Habbibi and colleagues and thank them for their recent contributions to the field of left atrial function, which as they infer, were neglected in my Stateof-the Art review (1). Calibrating the completeness of these reviews can be problematic and
RI PT
requires balancing the novelty of a method with its demonstrated validity and clinical utility. Tissue-tracking cardiac magnetic resonance (FT-CMR) is a new and potentially useful technique for measuring strain from routine cine CMR images using feature-tracking algorithms that were
SC
initially designed for echocardiographic strain analysis. FT-CMR tracks motion of a tissue voxel using standard steady-state free precession sequences, and is simpler, more practical and
M AN U
available, and less time-consuming than other CMR-based strain techniques. However, as Habibi et al state in their letter, reproducibility and repeatability data for FT-CMR ventricular strain measurements are conflicting (2). More recently, in a study of 145 healthy volunteers, global circumferential, but not longitudinal strain showed reasonable agreement with tagged CMR with
TE D
acceptable interobserver reproducibility (3). In another study there was considerable variability between FT-CMR and 2D speckle tracking echo strains of the RV and LV in 20 patients with tetralogy of Fallot and 20 controls (4). Importantly, reproducibility, variability and validation
EP
data for atrial FT-CMR (longitudinal) strain are nonexistent. Moreover, there are no studies in the peer-reviewed literature of FT-CMR atrial strain
AC C
measurement. Indeed, the studies cited by Habibi et al are abstracts that have not to date undergone a rigorous review process. These studies concluded that addition of FT-CMR LA strain helps discriminate subjects with atrial fibrillation from controls; that FT-CMR peak systolic atrial strain, but not left atrial volumes or emptying fraction, was associated with heart failure after adjusting for NT-BMP, traditional heart failure risk factors and LV mass; and that FT-CMR peak systolic left atrial strain and diastolic strain rate are associated with significant
2
ACCEPTED MANUSCRIPT
late gadolinium LV myocardial scar (2). The FT-CMR field is indisputably inchoate; acquisition technique, cine sequence, field strength and temporal resolution are variables that are likely to affect the accuracy and precision of FT-CMR measurements of atrial strain using CMR. The
RI PT
need for further pre-clinical analysis in addition to clinical trials was trumpeted in a recent editorial (5).
Finally, the focus of my review was the role of left atrial function on prognosis. While it is
SC
tempting to extrapolate from the experience of echocardiographic LA strain, there are no studies of FT-CMR LA strain that examine outcomes or that compare LA strain measured with FT-CMR
AC C
EP
TE D
M AN U
to echocardiography.
3
ACCEPTED MANUSCRIPT
BIBLIOGRAPHY 1. Hoit BD. Left Atrial Size and Function: Role in Prognosis. Journal of the AmericanCollege of Cardiology 2013; Nov 14. [Epub ahead of print]
RI PT
2. Habibi M, Venkatesh BA, Lima JAC. Letter to the editor: Feature tracking cardiac magnetic resonance imaging in the assessment of left atrial function. J Am Coll Cardiol. 2014. In press. 3. Augustine D, Lewandowski AJ, Lazdam M, et al. global and regional left ventricular
SC
myocardial deformation measures by magnetic resonance feature tracking in healthy volunteers: comparison with tagging and relevance of gender. J Cardiovasc Magn Reson. 2013;15:8.
M AN U
4. Padiyath A, Gribben P, Abraham JR, et al. Echocardiography and cardiac magnetic resonancebased feature tracking in the assessment of myocardial mechanics in tetralogy of Fallot: an intermodality comparison. Echocardiography 2013;30:203-10.
AC C
EP
TE D
5. Simonetti OP, Raman SV. Straining to justify strain measurement. JACC Img. 2010;3:152-4.
4
S0735-1097(14)01308-4
DOI:
10.1016/j.jacc.2014.02.544
Reference:
JAC 19949
To appear in:
Journal of the American College of Cardiology
Received Date: 4 February 2014 Accepted Date: 11 February 2014
Please cite this article as: Hoit BD, Reply to Letter to the Editor: feature tracking cardiac magnetic resonance imaging in the assessment of left atrial function, Journal of the American College of Cardiology (2014), doi: 10.1016/j.jacc.2014.02.544. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Reply to Letter to the Editor: feature tracking cardiac magnetic resonance imaging in the
RI PT
assessment of left atrial function
Brian D. Hoit, M.D.
M AN U
SC
Professor of Medicine, Physiology and Biophysics, Case Western Reserve University Director of Echocardiography, University Hospitals Case Medical Center
TE D
Disclosures. Dr. Hoit is a speaker for Philips Medical.
AC C
EP
Address for Reprints: Brian D Hoit Harrington Heart and Vascular Center University Hospitals Case Medical Center 11100 Euclid Avenue, Cleveland OH 44106-5038 (216) 844-3855 (216) 844-8954 (fax) [email protected]
1
ACCEPTED MANUSCRIPT
I appreciate the interest shown by Dr Habbibi and colleagues and thank them for their recent contributions to the field of left atrial function, which as they infer, were neglected in my Stateof-the Art review (1). Calibrating the completeness of these reviews can be problematic and
RI PT
requires balancing the novelty of a method with its demonstrated validity and clinical utility. Tissue-tracking cardiac magnetic resonance (FT-CMR) is a new and potentially useful technique for measuring strain from routine cine CMR images using feature-tracking algorithms that were
SC
initially designed for echocardiographic strain analysis. FT-CMR tracks motion of a tissue voxel using standard steady-state free precession sequences, and is simpler, more practical and
M AN U
available, and less time-consuming than other CMR-based strain techniques. However, as Habibi et al state in their letter, reproducibility and repeatability data for FT-CMR ventricular strain measurements are conflicting (2). More recently, in a study of 145 healthy volunteers, global circumferential, but not longitudinal strain showed reasonable agreement with tagged CMR with
TE D
acceptable interobserver reproducibility (3). In another study there was considerable variability between FT-CMR and 2D speckle tracking echo strains of the RV and LV in 20 patients with tetralogy of Fallot and 20 controls (4). Importantly, reproducibility, variability and validation
EP
data for atrial FT-CMR (longitudinal) strain are nonexistent. Moreover, there are no studies in the peer-reviewed literature of FT-CMR atrial strain
AC C
measurement. Indeed, the studies cited by Habibi et al are abstracts that have not to date undergone a rigorous review process. These studies concluded that addition of FT-CMR LA strain helps discriminate subjects with atrial fibrillation from controls; that FT-CMR peak systolic atrial strain, but not left atrial volumes or emptying fraction, was associated with heart failure after adjusting for NT-BMP, traditional heart failure risk factors and LV mass; and that FT-CMR peak systolic left atrial strain and diastolic strain rate are associated with significant
2
ACCEPTED MANUSCRIPT
late gadolinium LV myocardial scar (2). The FT-CMR field is indisputably inchoate; acquisition technique, cine sequence, field strength and temporal resolution are variables that are likely to affect the accuracy and precision of FT-CMR measurements of atrial strain using CMR. The
RI PT
need for further pre-clinical analysis in addition to clinical trials was trumpeted in a recent editorial (5).
Finally, the focus of my review was the role of left atrial function on prognosis. While it is
SC
tempting to extrapolate from the experience of echocardiographic LA strain, there are no studies of FT-CMR LA strain that examine outcomes or that compare LA strain measured with FT-CMR
AC C
EP
TE D
M AN U
to echocardiography.
3
ACCEPTED MANUSCRIPT
BIBLIOGRAPHY 1. Hoit BD. Left Atrial Size and Function: Role in Prognosis. Journal of the AmericanCollege of Cardiology 2013; Nov 14. [Epub ahead of print]
RI PT
2. Habibi M, Venkatesh BA, Lima JAC. Letter to the editor: Feature tracking cardiac magnetic resonance imaging in the assessment of left atrial function. J Am Coll Cardiol. 2014. In press. 3. Augustine D, Lewandowski AJ, Lazdam M, et al. global and regional left ventricular
SC
myocardial deformation measures by magnetic resonance feature tracking in healthy volunteers: comparison with tagging and relevance of gender. J Cardiovasc Magn Reson. 2013;15:8.
M AN U
4. Padiyath A, Gribben P, Abraham JR, et al. Echocardiography and cardiac magnetic resonancebased feature tracking in the assessment of myocardial mechanics in tetralogy of Fallot: an intermodality comparison. Echocardiography 2013;30:203-10.
AC C
EP
TE D
5. Simonetti OP, Raman SV. Straining to justify strain measurement. JACC Img. 2010;3:152-4.
4
