| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Ann Thorac Surg 2004;77:693
© 2004 The Society of Thoracic Surgeons
Division of Cardiovascular Surgery, The Mayo Clinic, 200 First St, SW, Rochester, MN 55905, USA
e-mail: sundt.thoralf{at}mayo.edu
The work reported by Dr Fukamachi and colleagues is intriguing on several counts. The device they describe is one of a growing number of novel surgical approaches to the management of end-stage heart failure. Equally exciting is the path the investigators took to developing the device—they made an incidental observation of reduced mitral regurgitation (MR) while testing a related device in an animal model of dilated cardiomyopathy. Admittedly, Craig Miller's laboratory has made similar observations in a model of acute ischemic MR with an "open-heart" device aimed at effecting "septal-lateral cinching" [1]; however these authors still deserve credit for making an unexpected observation and for recognizing its potential applications. Fortune favors the prepared mind.
These investigators have successfully demonstrated the effectiveness of an externally applied device in creating a shape change of the mitral annulus which favorably affects valve function. The device is uniquely appealing in that it can be applied "off-pump" and can be "tuned" real-time based on Echo. While the study admittedly does not address obvious potential complications of chronic implantation (migration of the pads etc), the acute results are tantalizing.
Is there a catch? The function of the valve may be improved, but what about the ventricle? In these animals, the central venous pressure rose and systemic pressure fell. While these changes were small in absolute magnitude, they were statistically significant and, importantly, were both decidedly in the wrong direction. They may have been due to an adverse impact of the device on diastolic function or the compressive effect of the anterior pad on the right ventricular outflow tract. Either would be undesirable.
Beyond these questions, what are the practical, clinical issues that must be confronted before introducing this technology into clinical practice? In which patients would this technology be applied? In whom would the potential benefits outweigh the potential risks? As the authors have referenced, the reported mortality rates in experienced hands for conventional mitral repair—even in the setting of poor left ventricular function—are less than 2% [2, 3]. Should we anticipate the risk of this procedure to be even less? If the device were to be applied to sicker patients than those we now operate on, how solid are the data that permit us to predict those patients in whom ventricular remodeling is reversible, late functional status is improved, and survival is superior with surgical intervention as compared to contemporary medical therapy? Ah, selection, selection, selection.
References
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
