Noncompaction of the Left Ventricle - A Rare Cause Of Non-ischemic Cardiomyopathy

Author: M. Auron, M.D, Department of Hospital Medicine, Cleveland Clinic
Reviewer: V. Dimov, M.D., Department of Hospital Medicine, Cleveland Clinic

A 560year-old African American male (AAM) with no significant past medical history presented to the ER with progressive dyspnea, epigastric pain and diaphoresis for one week.

Medications

None.

Physical examination

Bibasilar rales; irregular heart rate, S3 gallop, displaced PMI and pedal edema.

What is the most likely diagnosis?

Acute heart failure; rule-out myocardial infarction (MI).

What tests would you order?

Transthoracic echocardiogram, chest roentgenogram, cardiac enzymes (troponin I, CK, CK MB), BNP, EKG.

Initial laboratory results

CK 100 ng/ml, CK-MB 2.2 ng/ml, Troponin I 1.9 ng/ml.

EKG showed left bundle branch block with no ST changes.

What treatment would you start for this patient?

Presumptive diagnosis of NSTEMI was established and initial treatment included beta-blockers, oral acetyl-salicylic acid, heparin, tirofiban and furosemide.

What happened?

The patient underwent a cardiac catheterization that showed normal coronary arteries. An echocardiogram showed LVEF of 20% and increased trabeculation noted in the LV apex and posterolateral walls suggestive of non-compaction. Secondarily to multiple episodes of ventricular tachycardia during his admission, an ICD was placed.


Non-ischemic cardiomyopathy secondary to non-compaction of the left ventricle (click to enlarge the images).

Final diagnosis

Non-ischemic cardiomyopathy secondary to non-compaction of the left ventricle.

Discussion

Epidemiology

• Prevalence on LVNC in general population is unknown.
• In largest series it has been reported from 0.014% to 0.05%.
• Men are affected more frequently in 56-85% cases.
• Can affect any age group, decribed from 2 ->70 years.

Genetics

• Genetic linkage analysis - mutations in the gene G4.5 (Xq28).
• Genes for cytoskeletal proteins (alpha-dystrobrevin (P121L), Cypher/ZASP.
• Locus on chromosome 11p5 AD LVNC.

Clinical Manifestations

• CHF: systolic and/or diastolic dysfunction – 60 to 82% cases
• Progressive subendocardial ischemia and fibrosis
• Coronary microcirculatory dysfunction – depressed coronary flow reserve in all hypokinetic myocardial segments.
• Abnormal relaxation and restrictive hemodynamics secondary to trabecular network à diastolic dysfunction
• Arrhythmias
• Atrial fibrillation – 25% cases
• Ventricular tachyarrhythmias – 47% cases
• Pediatric population –15% incidence of WPW
• EKG – nonspecific (LVH, repolarization, ST-T, LBBB)
• Thromboembolism (38% cases)
• CVA, TIA
• Related to development of thrombi in the trabeculated ventricle, depressed systolic function or atrial fibrillation.

Diagnosis

• Echocardiogram – Quantitative evaluation determining the ratio on maximal thickness of the non-compacted (NC) to compacted (C), measured at the end systole in parasternal short axis view with a ratio greater than 2. (See figure A, B, C).

What did we learn from this case?

• Isolated LVNC is an infrequent but not rare cause of cardiomyopathy.
• LVNC presents with more severely depressed ventricular function than other cardiomyopathies.
• LVNC can present clinically in three forms: CHF, arrhythmias or thromboembolism.
• The high morbidity and mortality associated with LVNC should prompt an increased awareness of it for an early diagnosis and treatment.

References

1. Engherding R, et al. Identification of a rare congenital anomaly of the myocardium by two-dimensional echocardiography: persistence of isolated myocardial sinusoids. Am J Cardiol. 1984; 54:1733-4.
2. Elias J, et al. Isolated non-compaction of the myocardium. Arq Bras Cardiol. 2000; 74: 253-61
3. Oeschlin EN, et al. Long-term follow-up of 34 adults with isolated left ventricular non-compaction: a distinct cardiomyopathy with poor prognosis. J Am Coll Cardiol. 2000: 36: 493-500.
4. Ritter M, et al. Isolated non-compaction of the myocardium in adults. Mayo Clin Proced. 1997; 72: 26-31.
5. De Groot-de Laat LE, et al. Usefulness of contrast echocardiography for diagnosis of left ventricular noncompaction. Am J Cardiol. 2005; 95: 1130-1134.
6. Ichida F, et al. Clinical features of isolated noncompaction of the ventricular myocardium: long-term clinical course, hemodynamic properties and genetic background. J Am Coll Cardiol. 1999; 34: 233-40.
7. Sasse-Klaasen S, et al. Isolated noncompaction of the left ventricular myocardium in the adult is an autosomal dominant disorder in the majority of patients. Am J Med Genet. 2003; 119: 162-7
8. Ichida F, et al. Novel gene mutations in patients with left ventricular noncompaction or Barth syndrome. Circulation. 2001: 103:1256.
9. Vatta M, et al. Mutations in cypher/ZASP in patients with dilated cardiomyopathy and left ventricular non-compaction. J Am coll Cardiol. 2003; 42: 2014.
10. Sasse-Klassen S, et al. Novel gene locus for autosomal dominant left ventricular noncompaction maps to chromosoe 11p15. Circulation. 2004; 109:2720.
11. Chin TK, et al. Isolated noncompaction of the left ventricular myocardium. A study of eight cases. Circulation. 1990; 82: 507-513.
12. Junga G, et al. Myocardial ischemia in children with isolated ventricular non-complaction. Eur Heart J. 1999; 20: 910-16.
13. Kauffman PA, et al. Isolated ventricular non-compaction is associated with coronary microvascular dysfunction. J Am Coll Cardiol. 2001; 37: 187A.
14. Agmon Y, et al. Noncompaction of the ventricular myocardium. J Am Soc Echocardiogr. 1999; 12: 859-863.
15. Rigopoulos A, et al. Isolated left ventricular noncompaction: an unclassified cardiomyopathy with severe prognosis in adults. Cardiology. 2002; 98: 25-32.

Published: 01/21/2008
Updated: 04/07/2010

2 comments:

  1. I am writing on behalf of a friend who has been diagnosed with this. We have been told this is a very rare disease and are seeking immediate help and information. He is a 43 year old male in relatively good health a local fire fighter. He presented with some fainting over the last week or so and went to the Hospital of Saint Raephals, in New Haven, Connecticut. They have run a battery of test and this was his diagnosis. They are highly suggesting an ICD. We are actviley looking for some help and information.

    my email is mbeisler2000@yahoo.com
    Any help or information would be greatly appreciated

    ReplyDelete
  2. I would call the Cleveland Clinic for second opinion.

    ReplyDelete