title: Left ventricular noncompaction cardiomyopathy in end-stage heart failure patients undergoing orthotopic heart transplantation.
abstract: BACKGROUND
  Previous studies reported that left ventricular noncompaction (LVNC) is a cardiomyopathy, familial or sporadic, arising from arrest of the normal process of trabecular remodeling during embryonic development. The diagnosis is usually made by echocardiography, but to date, there has been little research on the occurrence and clinicopathological features of LVNC in the explanted hearts of orthotopic heart transplant (OHT) recipients.
  
  
  METHODS
  The clinical, echocardiographic, and pathologic findings were reviewed for evidence of LVNC, diagnosed by echocardiographic criteria, in 105 patients with end-stage heart failure (HF) undergoing OHT. Analyses of multiple sections of the explanted hearts were carried out. The hearts were evaluated for grades (0, negative; 1, mild/occasional foci; 2, moderate/multiple foci; 3, severe/extensive, diffuse) of fibrosis, reactive and replacement, hypertrophy, myocytolysis in left ventricle, right ventricle, interventricular septum, and atria. Absolute measurements of noncompacted and compacted portions of the left ventricle wall and noncompacted/compacted ratios were calculated.
  
  
  RESULTS
  Isolated LVNC was observed in 0 of 54 ischemic cardiomyopathy and in 4 of 51 (7.8%) nonischemic cardiomyopathy patients - 2 men and 2 women, with a mean age±SEM of 34.2±6.9years. The echocardiogram disclosed marked left ventricular dilatation, prominent trabeculations, and left ventricle ejection fraction <20%. Mural thrombi were seen in 3 of 4 (75%) patients. The heart weight mean±SEM was 468±55.3 g (range, 340-600g); noncompacted myocardium was 22±5.8mm, compacted myocardium was 13.2±3.5mm, and noncompacted/compacted ratio was 1.7/1±0.2. The total scores of hypetrophy, myocytolysis, and fibrosis were as follows: left ventricle, 7.7±0.2; right ventricle, 6.2±0.5; interventricular septum, 6.7±0.2; and atria, 7.5±0.3.
  
  
  CONCLUSIONS
  LVNC is an unusual form of nonischemic cardiomyopathy in patients suffering from end-stage HF undergoing OHT. The variability in the noncompacted/compacted ratio and discordance between the echocardiographic and pathological findings points to the need for further clarification of diagnostic imaging and diagnostic criteria for LVNC. Further studies in larger series, correlating the anatomoclinical and genetic variables, also would improve our understanding of LVNC as a cause of advanced HF leading to OHT.
authors.affiliation: Department of Pathology and Laboratory Medicine, The University of Texas Health Science Center at Houston, Houston, TX, USA; "Lino Rossi" Research Center for the study and prevention of unexpected perinatal death and sudden infant death syndrome (SIDS)-Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy. Electronic address: Giulia.M.Ottaviani@uth.tmc.edu.
authors.forename: Giulia
authors.initials: G
authors.lastname: Ottaviani
authors.affiliation: Cardiovascular Pathology Research Laboratory, Texas Heart Institute, CHI St. Luke's Hospital, Houston, TX, USA.
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Segura
authors.affiliation: Center for Advanced Heart Failure, Memorial Hermann-Texas Medical Center, The University of Texas Health Science Center at Houston, Houston, TX, USA.
authors.forename: Indranee N
authors.initials: IN
authors.lastname: Rajapreyar
authors.affiliation: Department of Pathology and Laboratory Medicine, The University of Texas Health Science Center at Houston, Houston, TX, USA.
authors.forename: Bihong
authors.initials: B
authors.lastname: Zhao
authors.affiliation: Center for Advanced Heart Failure, Memorial Hermann-Texas Medical Center, The University of Texas Health Science Center at Houston, Houston, TX, USA.
authors.forename: Rajko
authors.initials: R
authors.lastname: Radovancevic
authors.affiliation: Center for Advanced Heart Failure, Memorial Hermann-Texas Medical Center, The University of Texas Health Science Center at Houston, Houston, TX, USA.
authors.forename: Pranav
authors.initials: P
authors.lastname: Loyalka
authors.affiliation: Center for Advanced Heart Failure, Memorial Hermann-Texas Medical Center, The University of Texas Health Science Center at Houston, Houston, TX, USA.
authors.forename: Biswajit
authors.initials: B
authors.lastname: Kar
authors.affiliation: Center for Advanced Heart Failure, Memorial Hermann-Texas Medical Center, The University of Texas Health Science Center at Houston, Houston, TX, USA.
authors.forename: Igor
authors.initials: I
authors.lastname: Gregoric
authors.affiliation: Department of Pathology and Laboratory Medicine, The University of Texas Health Science Center at Houston, Houston, TX, USA; Cardiovascular Pathology Research Laboratory, Texas Heart Institute, CHI St. Luke's Hospital, Houston, TX, USA.
authors.forename: L Maximilian
authors.initials: LM
authors.lastname: Buja
mesh_terms: D000328:Adult; D000368:Aged; D004452:Echocardiography; D005260:Female; D006333:Heart Failure / Q000209:etiology* / Q000473:pathology*; D016027:Heart Transplantation; D006352:Heart Ventricles / Q000473:pathology*; D006801:Humans; D056830:Isolated Noncompaction of the Ventricular Myocardium / Q000150:complications* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D055815:Young Adult
keywords: Explanted heart; Fibrosis; Heart failure; Hypertrophy; Left ventricular noncompaction cardiomyopathy; Myocardial remodeling; Myocytolysis; Nonischemic cardiomyopathy; Orthotopic heart transplantation