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noncompaction dependent on ventricular shape and function?
READERS’ COMMENTS Is Left Ventricular Hypertrabeculation/Noncompaction Dependent on Ventricular Shape and Function?
In their article “Comparison of Echocardiographic Features of Noncompaction of the Left Ventricle in Adults Versus Idiopathic Dilated Cardiomyopathy in Adults,” Sengupta et al1 address the important issue of the echocardiographic diagnosis of left ventricular hypertrabeculation/noncompaction (LVHT). By comparing 32 patients with LVHT and 20 patients with idiopathic dilated cardiomyopathy, they found that left ventricular shape, as assessed by the sphericity index, differs between both groups. In LVHT, an inappropriate degree of spherical remodeling was detected. The authors speculate that LVHT may be responsible for this phenomenon. However, these findings raise several questions. Stating in the introduction that LVHT represents “an arrest in endomyocardial morphogenesis,” the authors do not seem to be aware that LVHT is not only a congenital cardiac abnormality but may also develop during a lifetime in single cases.2 Furthermore, they miss mentioning that another definition of LVHT is also used in the literature: ⬎3 trabeculations protruding from the left ventricular wall, apically to the papillary muscles, visible in 1 image plane, and intertrabecular spaces perfused from the ventricular cavity, as visualized on color Doppler imaging.3 It is not clear how the sphericity index and the meridional/longitudinal diameter ratio was calculated. How was the apical endocardial border defined for measurement of the longitudinal left ventricular diameter4: as the tip of a trabeculaLetters (from the United States) concerning a particular article in The American Journal of Cardiology姞 must be received within 2 months of the article’s publication, and should be limited (with rare exceptions) to 2 doublespaced typewritten pages. Two copies must be submitted.
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tion or the depth of an intertrabecular recessus? Were inter- and intraobserver variabilities of these measurements tested? Which of the participating centers recruited how many patients? The inclusion of 3 patients with aortic stenosis disagrees with the definition of LVHT as an “isolated cardiomyopathy.” Did both groups differ regarding disease duration, electrocardiographic abnormalities, and left ventricular dimensions? LVHT has been shown to be associated with neuromuscular disorders in up to 82% of the cases.3 Thus, neurologic findings would be of interest. In how many of the myocardial segments was it possible to assess the presence or absence of LVHT? In how many cases was it actually possible to measure the ratio of noncompacted to compacted myocardial layer at end-systole? Our experience is that trabeculations are more easily visible during diastole. How many patients had how many noncompacted segments? Did the number of noncompacted segments correlate with the sphericity index, age, or disease duration? Do the authors have any explanation for the absence of LVHT in the interventricular septum, which has also been described by others?2 Did the 2 patients, in whom intertrabecular thrombi were detected, have a history of arterial embolism? Did they have atrial fibrillation or coagulation abnormalities? Were the thrombi confirmed by cardiac magnetic resonance imaging? Did they resolve after anticoagulant therapy? The statement that LVHT is associated with systolic dysfunction is not in accordance with our findings, which show that systolic dysfunction is only present in 56% of the LVHT cases.5 LVHT occurs not only in hypokinetic but also in normally contracting myocardial regions. We confirm that it is important to recognize LVHT echocardiographically and to distinguish it from other abnormalities. For this purpose it is important to
©2005 by Excerpta Medica Inc. All rights reserved. The American Journal of Cardiology Vol. 95 April 1, 2005
develop a common definition of LVHT that is clinically applicable. Claudia Sto¨llberger, MD Josef Finsterer, MD, PhD Vienna, Austria 1 September 2004
1. Sengupta PP, Mohan JC, Mehta V, Jain V, Arora R, Pandian NP, Khandheria BK. Comparison of echocardiographic features of noncompaction of the left ventricle in adults versus idiopathic dilated cardiomyopathy in adults. Am J Cardiol 2004;94:389 – 391. 2. Stöllberger C, Finsterer J. Left ventricular hypertrabeculation/noncompaction. J Am Soc Echocardiogr 2004;17:91–100. 3. Stöllberger C, Finsterer J, Blazek G. Left ventricular hypertrabeculation/noncompaction and association with additional cardiac abnormalities and neuromuscular disorders. Am J Cardiol 2002;90:899 – 902. 4. Paraskevaidis IA, Dodouras T, Adamapoulos S, Kremastinos DTh. Effects of dobutamine on left ventricular shape and geometry: an easy way to detect the functional status of chronic heart failure in patients with dilated cardiomyopathy. J Am Soc Echocardiogr 2003;16:132–139. 5. Stöllberger C, Finsterer J. Cardiologic and neurologic findings in left ventricular hypertrabeculation/ non-compaction related to wall thickness, size and systolic function. Eur J Heart Fail 2004; in press.
doi:10.1016/j.amjcard.2004.09.055
REPLY: We thank Dr. Stöllberger and Dr. Finsterer for their interest in our Brief Report on the use of echocardiography to distinguish left ventricular (LV) noncompaction (NC) from idiopathic dilated cardiomyopathy (IDC). Our answers to their queries are detailed in the following. (1) During embryologic development, transmural maturation occurs by a process of compaction; NC, therefore, has been considered a developmental defect in endomyocardial morphogenesis.1,2 It has been suggested that NC in isolated cases could result from a morphologic regression from an adult pattern to an embryologic pattern, but this has not been confirmed. (2) A single working definition of NC derived from clinical and pathologic observations in earlier investigations was used uniformly throughout the study.3,4 (3) For calculating the sphericity index and meridional longitudinal diameter ratio, LV dimensions were measured from the inner visible 0002-9149/05/$–see front matter
In their article “Comparison of Echocardiographic Features of Noncompaction of the Left Ventricle in Adults Versus Idiopathic Dilated Cardiomyopathy in Adults,” Sengupta et al1 address the important issue of the echocardiographic diagnosis of left ventricular hypertrabeculation/noncompaction (LVHT). By comparing 32 patients with LVHT and 20 patients with idiopathic dilated cardiomyopathy, they found that left ventricular shape, as assessed by the sphericity index, differs between both groups. In LVHT, an inappropriate degree of spherical remodeling was detected. The authors speculate that LVHT may be responsible for this phenomenon. However, these findings raise several questions. Stating in the introduction that LVHT represents “an arrest in endomyocardial morphogenesis,” the authors do not seem to be aware that LVHT is not only a congenital cardiac abnormality but may also develop during a lifetime in single cases.2 Furthermore, they miss mentioning that another definition of LVHT is also used in the literature: ⬎3 trabeculations protruding from the left ventricular wall, apically to the papillary muscles, visible in 1 image plane, and intertrabecular spaces perfused from the ventricular cavity, as visualized on color Doppler imaging.3 It is not clear how the sphericity index and the meridional/longitudinal diameter ratio was calculated. How was the apical endocardial border defined for measurement of the longitudinal left ventricular diameter4: as the tip of a trabeculaLetters (from the United States) concerning a particular article in The American Journal of Cardiology姞 must be received within 2 months of the article’s publication, and should be limited (with rare exceptions) to 2 doublespaced typewritten pages. Two copies must be submitted.
922
tion or the depth of an intertrabecular recessus? Were inter- and intraobserver variabilities of these measurements tested? Which of the participating centers recruited how many patients? The inclusion of 3 patients with aortic stenosis disagrees with the definition of LVHT as an “isolated cardiomyopathy.” Did both groups differ regarding disease duration, electrocardiographic abnormalities, and left ventricular dimensions? LVHT has been shown to be associated with neuromuscular disorders in up to 82% of the cases.3 Thus, neurologic findings would be of interest. In how many of the myocardial segments was it possible to assess the presence or absence of LVHT? In how many cases was it actually possible to measure the ratio of noncompacted to compacted myocardial layer at end-systole? Our experience is that trabeculations are more easily visible during diastole. How many patients had how many noncompacted segments? Did the number of noncompacted segments correlate with the sphericity index, age, or disease duration? Do the authors have any explanation for the absence of LVHT in the interventricular septum, which has also been described by others?2 Did the 2 patients, in whom intertrabecular thrombi were detected, have a history of arterial embolism? Did they have atrial fibrillation or coagulation abnormalities? Were the thrombi confirmed by cardiac magnetic resonance imaging? Did they resolve after anticoagulant therapy? The statement that LVHT is associated with systolic dysfunction is not in accordance with our findings, which show that systolic dysfunction is only present in 56% of the LVHT cases.5 LVHT occurs not only in hypokinetic but also in normally contracting myocardial regions. We confirm that it is important to recognize LVHT echocardiographically and to distinguish it from other abnormalities. For this purpose it is important to
©2005 by Excerpta Medica Inc. All rights reserved. The American Journal of Cardiology Vol. 95 April 1, 2005
develop a common definition of LVHT that is clinically applicable. Claudia Sto¨llberger, MD Josef Finsterer, MD, PhD Vienna, Austria 1 September 2004
1. Sengupta PP, Mohan JC, Mehta V, Jain V, Arora R, Pandian NP, Khandheria BK. Comparison of echocardiographic features of noncompaction of the left ventricle in adults versus idiopathic dilated cardiomyopathy in adults. Am J Cardiol 2004;94:389 – 391. 2. Stöllberger C, Finsterer J. Left ventricular hypertrabeculation/noncompaction. J Am Soc Echocardiogr 2004;17:91–100. 3. Stöllberger C, Finsterer J, Blazek G. Left ventricular hypertrabeculation/noncompaction and association with additional cardiac abnormalities and neuromuscular disorders. Am J Cardiol 2002;90:899 – 902. 4. Paraskevaidis IA, Dodouras T, Adamapoulos S, Kremastinos DTh. Effects of dobutamine on left ventricular shape and geometry: an easy way to detect the functional status of chronic heart failure in patients with dilated cardiomyopathy. J Am Soc Echocardiogr 2003;16:132–139. 5. Stöllberger C, Finsterer J. Cardiologic and neurologic findings in left ventricular hypertrabeculation/ non-compaction related to wall thickness, size and systolic function. Eur J Heart Fail 2004; in press.
doi:10.1016/j.amjcard.2004.09.055
REPLY: We thank Dr. Stöllberger and Dr. Finsterer for their interest in our Brief Report on the use of echocardiography to distinguish left ventricular (LV) noncompaction (NC) from idiopathic dilated cardiomyopathy (IDC). Our answers to their queries are detailed in the following. (1) During embryologic development, transmural maturation occurs by a process of compaction; NC, therefore, has been considered a developmental defect in endomyocardial morphogenesis.1,2 It has been suggested that NC in isolated cases could result from a morphologic regression from an adult pattern to an embryologic pattern, but this has not been confirmed. (2) A single working definition of NC derived from clinical and pathologic observations in earlier investigations was used uniformly throughout the study.3,4 (3) For calculating the sphericity index and meridional longitudinal diameter ratio, LV dimensions were measured from the inner visible 0002-9149/05/$–see front matter