Author + information
- Rohan S. Wijesurendra, MBBChir, MA,
- Alexander Liu, MBBS,
- Vanessa M. Ferreira, MD, DPhil,
- Stefan Neubauer, MD and
- Barbara Casadei, MD, DPhil∗ ()
- ↵∗British Heart Foundation, Division of Cardiovascular Medicine, University of Oxford, Level 6, West Wing, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, United Kingdom
We read with great interest the paper by Mueller et al. (1) describing the results of right ventricular septal biopsy in 189 patients with new-onset nonischemic heart failure and severely reduced ejection fraction. Criteria for tachycardiomyopathy (TCM), including admission heart rate ≥100 beats/min, were retrospectively fulfilled in 19 cases. TCM was due to atrial fibrillation (AF) in 16 cases and atrial flutter in 2 cases (1). TCM was associated with a distinct pattern of changes in myocardial structure from those seen in inflammatory or dilated cardiomyopathy, including less marked myocardial fibrosis and higher prevalence of a specific mitochondrial distribution pattern in close proximity to intercalated disks, suggesting a link to energetic dysfunction.
The authors are to be congratulated on this detailed investigation and unique set of data. From their results, we infer that left ventricular function did not normalize during follow-up in the TCM group despite successful rhythm and/or rate control, given mean improvement in ejection fraction of ∼15% from a baseline of ∼29% (1), raising the possibility that an underlying cardiomyopathy may have been exacerbated by uncontrolled arrhythmia.
We recently demonstrated impaired myocardial energetics that persist despite successful catheter ablation in patients with “lone” AF, controlled ventricular rate, and subtle left ventricular dysfunction (2). In light of our findings, we question whether endomyocardial biopsy results could reflect the preponderance of AF in the TCM group rather than tachycardia per se, particularly because a single heart rate assessment may not accurately reflect the overall heart rate profile. In this respect, it would be helpful if the authors could also comment on the comparison of endomyocardial biopsy results between patients in AF at admission (of which there were 45 in total) and those in sinus rhythm (n = 132), irrespective of admission heart rate or retrospective classification as TCM. Confirmation of specific left ventricular histological changes in patients with AF would support the paradigm of AF-related cardiomyopathy (2) and guide novel therapeutic strategies (3).
Please note: The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- 2017 American College of Cardiology Foundation
- Mueller K.A.L.,
- Heinzmann D.,
- Klingel K.,
- et al.
- Wijesurendra R.S.,
- Liu A.,
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- et al.
- Hyman M.C.,
- Callans D.J.