New onset heart failure in a 29-year-old: a case report of isolated left ventricular noncompaction.

Abstract: A previously healthy 29-year-old patient presented with new onset congestive heart failure. Based on findings on transthoracic echocardiogram (TTE) and cardiac magnetic resonance imaging (MRI) at an outside center, the patient was diagnosed as having a dilated cardiomyopathy with structural abnormalities in the ventricular septum and left ventricular (LV) apex suspicious for myocardial tumor. After referral to our center for further management, repeat TTE revealed findings characteristic of left ventricular non-compaction (LVNC) with severely depressed overall LV systolic function. Review of the outside cardiac MRI supported the diagnosis of LVNC. Final management consisted of traditional medical therapy for congestive heart failure, an implantable cardiac defibrillator (ICD), warfarin anticoagulation for the prevention of thromboembolism and referral for cardiac transplant.

Key Words: left ventricular noncompaction, cardiac MRI, echocardiography, cardiomyopathy, heart failure

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This case report reviews the differential diagnosis between left ventricular noncompaction (LVNC) and other conditions. LVNC is a rare congenital cardiomyopathy that appears to result from the intrauterine arrest of endomyocardial morphogenesis. (1-3) Two forms of this disorder have been described: an isolated form and a nonisolated form associated with other congenital heart disease (NLVNC). In the latter, ventricular septal defects, pulmonic stenosis, and hypoplastic left ventricle have been described to coexist. Presentation for patients with LVNC commonly includes symptoms of heart failure, cardiac arrhythmias, and thromboembolic events. (4) The final diagnosis is commonly made in both children and adults with a transthoracic echocardiogram (TTE). (5) TTE typically reveals a dilated left ventricle with multiple prominent intraventricular trabeculations and recesses commonly involving the apical and midventricular segments.

Case Report

A 29-year-old African-American female presented to her local cardiologist with new onset dyspnea on exertion, lower extremity and abdominal swelling, orthopnea and paroxysmal nocturnal dyspnea. She underwent a transthoracic echocardiogram (TTE) that was interpreted as dilated cardiomyopathy with an ejection fraction < 30% and an unusual appearance of the ventricular septum and lateral wall suspicious for infiltration by possible tumor. Doppler showed moderate mitral regurgitation and moderate tricuspid regurgitation. The patient was transferred to a university hospital where she was diuresed and started on low-dose angiotensin-converting enzyme inhibition and beta blocker therapy. She improved and was discharged with scheduled outpatient cardiac magnetic resonance imaging (MRI) to further evaluate for the possible cardiac mass. The cardiac MRI revealed a severely dilated left ventricle (LV) with an ill-defined mass felt to be consistent with a malignancy, perhaps a rhabdomyosarcoma or angiosarcoma. The patient was referred to our center for further management including potential myocardial biopsy to rule out intracardiac tumor. At our center, the patient underwent repeat TTE that revealed severe LV enlargement and a deeply trabeculated LV apex with multiple large recesses (Fig. 1). Low-scale color flow Doppler confirmed that these recesses were perfused from the left ventricular cavity, characteristic of left ventricular noncompaction (LVNC, Fig. 2). Review of the outside cardiac MRI (Fig. 3 and 4) revealed findings that further supported the diagnosis. On review of family history, the patient denied any history of cardiac disease, congestive heart failure, arrhythmias or sudden death. Management based on the new diagnosis of LVNC included optimization of medical therapy for congestive heart failure, implantation of an ICD, warfarin anticoagulation for prevention of systemic thromboembolism and referral for cardiac transplant. Serial echocardiography has shown findings (further refuting the possibility of intracardiac tumor).

Discussion

This case is remarkable because it involves new onset heart failure in a previously healthy young individual due to a rare congenital cardiac condition. The case confirms the importance of correctly identifying the defect using TTE, as making the diagnosis has a serious impact on prognosis and subsequent management decisions.

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Isolated left ventricular noncompaction (LVNC) is a rare congenital cardiomyopathy that appears to result from the intrauterine arrest of endomyocardial morphogenesis that occurs in week 5 to 8 of fetal life. (1-3) Noncompaction of the left ventricle has been categorized as an unclassified cardiomyopathy by the World Health Organization, having its own distinct cause and prognosis. (3) It is diagnosed in children and adults. Its common presentation involves heart failure, ventricular arrhythmias and thromboembolic events. (4) It is considered a rare disorder with a prevalence of 0.06% in all echocardiographic examinations performed over a 10-year period in an adult referral population. (6) A recent childhood population-based study suggests that the disease may be more frequent (6.9% in all primary cardiomyopathy patients).

LVNC does not have an invariably fatal course when diagnosed in the neonatal period. A significant number of patients have transient recovery of function followed by later deterioration, which may account for many patients presenting as adults. (7) Familial occurrence is common in the reported cases of LVNC, reaching up to 50% of cases in one study. (8-11) Although the unique echocardiographic picture may lead to the correct diagnosis of this condition, it is often misdiagnosed or unrecognized, commonly being mistaken for dilated or hypertrophic cardiomyopathy. (4)

Jenni et al (5) set criteria to accurately diagnose LVNC by echocardiography using 2-dimensional imaging and low scale color flow Doppler. Echocardiographic features include the presence of a thin (compacted) epicardium and a thick, spongy endocardial (noncompacted) surface with extensive trabeculation and sinusoid formation. Communication between the left ventricular cavity and the deep intertrabecular recesses can be demonstrated by low scale color flow Doppler. In the majority of cases the noncompacted myocardium involves the mid lateral, apical, or inferior walls. (12) Usually a ratio of noncompacted/compacted zone [greater than or equal to] 2 is diagnostic for ventricular noncompaction; however, there have been patients identified with a ratio between 1.4 to 2.0. (12) Both LV systolic and diastolic dysfunction and right ventricular involvement have been described in individual patients with this condition. (12-14) In those with LV systolic dysfunction, the hypokinetic segments can occur in both the affected area and the surrounding normally compacted myocardial segments. (12) It should be emphasized that the LV systolic function may be preserved at the time of presentation. (15,16) One case series also suggests that abnormalities in the structure and coaptation of mitral leaflets may be a specific echocardiographic finding for patients with LVNC, with or without preserved systolic function. (16)

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There is no specific treatment for LVNC and therapeutic measures are directed at dealing with the patient's symptoms (heart failure, cardiac arrhythmias, thromboembolic events) including consideration for cardiac transplantation. In one case series of 17 adult patients diagnosed with isolated LVNC (mean follow up of 6 years), eight of the patients died and two underwent cardiac transplantation. (4,17) In a larger case series of 34 patients followed for a mean of 44 months, 40% of patients had ventricular tachyarrhythmia and 35% died including six patients with sudden cardiac death. (10) Therefore, placement of an ICD should be strongly considered for long-term management. Because of the high incidence of complications, early diagnosis is important and screening of living relatives using echocardiography is warranted to detect asymptomatic patients within the family.

Conclusion

This case illustrates that LVNC can be easily misinterpreted as another form of cardiomyopathy or as an intracardiac mass, particularly among adult patients in whom the condition is rare. In this report we show how successful diagnosis of LVNC can be made with TTE through optimizing visualization of deep trabecular recesses and showing communication of these recesses with the LV cavity using off-axis angulation and low scale color flow Doppler. Making this diagnosis is of major importance as it can significantly influence decisions on long-term management, on prognosis and on the need to screen living relatives.

References

1. Varnava AM. Isolated non-compaction: a distinct cardiomyopathy? Heart 2001;86:599-600.

2. Richardson P, McKenna W, Bristow M, et al. Report of the 1995 World Health Organization/International Society and Federation of Cardiology Task Force on the Definition and Classification of Cardiomyopathies. Circulation 1996;93:841-842.

3. Tamborini G, Pepi M, Celeste F, et al. Incidence and characteristics of left ventricular false tendons and trabeculation in the normal and pathologic heart by second harmonic echocardiography. J Am Soc Echocardiogr 2004;17:367-374.

4. Rigopoulos A, Rizos IK, Aggeli C, et al. Isolated left ventricular non-compaction: an unclassified cardiomyopathy with severe prognosis in adults. Cardiology 2002;98:25-32.

5. Jenni R, Oechslin E, Schneider J, et al. Echocardiographic and pathoanatomical characteristics of isolated left ventricular non-compaction: a step towards classification as a distinct cardiomyopathy. Heart 2001;86:666-671.

6. Ozkutlu S, Ayabakan C, Celiker A. Noncompaction of ventricular myocardium: a study of twelve patients. J Am Soc Echocardiogr 2002;15:1523-1528.

7. Pagnatelli RH, McMahon CJ, Dreyer WJ, et al. Clinical characterization of left ventricular noncompaction in children: a relatively common form of cardiomyopathy. Circulation 2003;108:2672-2678.

8. Kurosaki K, Ikeda U, Hojo Y, et al. Familial isolated noncompaction of the left ventricular myocardium. Cardiology 1999;91:69-72.

9. Chin TK, Perloff JK, Williams RG, et al. Isolated noncompaction of left ventricular noncompaction of the left ventricular myocardium: a study of eight cases. Circulation 1990;82:507-513.

10. Oechlin EN, Attenhofer Jost CH, Rojas JR, et al. Long-term follow-up of 34 adults with isolated left ventricular noncompaction: a distinct cardiomyopathy with poor prognosis. J Am Coll Cardiol 2000;36:493-500.

11. Bleyl SB, Mumford BR, Brown-Harrison MC, et al. Xq28-linked non-compaction of the left ventricular myocardium: prenatal diagnosis and pathologic analysis of affected individuals. Am J Genet 1997;72:257-265.

12. Wood MJ, Picard MH. Utility of echocardiography in the evaluation of individuals with cardiomyopathy. Heart 2004;90:707-712.

13. Ichida F, Hammamichi Y, Miyawaki T, et al. Clinical features of isolated noncompaction of the ventricular myocardium. J Am Coll Cardiol 1999;34:233-240.

14. Agmon Y, Connolly HM, Olson LJ, et al. Noncompaction of the ventricular myocardium. J Am Soc Echocardiogr 1999;12:859-863.

15. Ali SKM, Du Plessis J, Godman M. Non-compaction of ventricular myocardium: clinical and echocardiographic features of 8 cases. Heart 2002;88:iv29.

16. Ali SK, Omran AS, Najm H, et al. Noncompaction of the ventricular myocardium associated with mitral regurgitation and preserved ventricular systolic function. J Am Soc Echocardiogr 2004;17:87-90.

17. Ritter M, Oechslin E, Sutsch G, et al. Isolated noncompactin of the myocardium in adults. Mayo Clin Proc 1997;72:26-31.

That is true wisdom, to know how to alter one's mind when occasion
Demands it.
--Terence

Ervin H. Fox, MD, MPH, Michael L. Wood, MD, John Trotter, MD, and Charles Moore, MD

From the University of Mississippi Medical Center, Jackson, MS.

Reprint requests to Ervin Fox, MD, MPH, Co-investigator, Jackson Heart Study, Assistant Professor of Medicine, University of MS Medical Center. 2500 North State Street, Jackson, MS 39216. Email: [e-mail]

Accepted April 21, 2006.

RELATED ARTICLE: Key Points

* Isolated left ventricular noncompaction (LVNC) is a rare congenital cardiomyopathy that appears to result from the intrauterine arrest of endomyocardial morphogenesis that occurs in week 5 to 8 of fetal life.

* Its common presentation involves heart failure, ventricular arrhythmias and thromboembolic events.

* Familial occurrence is common in the reported cases of LVNC, reaching up to 50% of cases in one study.

* Echocardiographic features include the presence of a thin (compacted) epicardium, the presence of a thick, spongy endocardial (noncompacted) surface with extensive trabeculation and evidence of communication between the left ventricular cavity and the deep intertrabecular recesses on low scale color flow Doppler.

* There is no specific treatment for LVNC and therapeutic measures are directed at dealing with the patient's symptoms (heart failure, cardiac arrhythmias, thromboembolic events) and consideration for defibrillator placement and/or cardiac transplantation.