Reproducibility of echocardiographic diagnosis of left ventricular noncompaction.
BACKGROUND
Left ventricular noncompaction (LVNC) cardiomyopathy is variably defined by numerous trabeculations, deep intertrabecular recesses, and noncompacted-to-compacted (NC/C) ratio >2. Limited studies exist on the reproducibility of diagnosing LVNC.


METHODS
Clinical records of patients diagnosed with LVNC by echocardiography were reviewed. Blinded review of the index echocardiogram for all patients and a 1:1 match without LVNC was performed independently by two observers, measuring the number of trabeculations and the NC/C ratio.


RESULTS
A total of 104 patients with LVNC were included in the study, 52 with no congenital heart disease (NCongHD) and 52 with congenital heart disease (CongHD). The duration of follow-up was 7.2 years (range, 0.5-23.1 years) for NCongHD and 8.2 years (range, 0-33.3 years) for CongHD. Agreement between observers in determining zero to three versus more than three trabeculations was 59% (NCongHD) and 73% (CongHD). Agreement in measuring an NC/C ratio ≤ 2 versus > 2 was 79% (NCongHD) and 74% (CongHD). Agreement with the original reader in diagnosing LVNC was 67%. There was no association between the number of trabeculations or the NC/C ratio and the likelihood of a major event. Patients with moderate or severe left ventricular dysfunction at the time of diagnosis were more likely to undergo cardiac transplantation or die compared with those with normal or mild dysfunction (NCongHD, 22% vs 0%, P = .01; CongHD, 39% vs 3%, P = .001).


CONCLUSIONS
The reproducibility of making measurements to diagnose LVNC by accepted criteria is poor. Heart transplantation and death are associated with significant ventricular dysfunction and not with increased trabeculations or NC/C ratios.
Department of Cardiology, Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts 02115, USA. susan.saleeb@cardio.chboston.org
Susan F
SF
Saleeb
Renee
R
Margossian
Carolyn T
CT
Spencer
Mark E
ME
Alexander
Leslie B
LB
Smoot
Adam L
AL
Dorfman
Lisa
L
Bergersen
Kimberlee
K
Gauvreau
Gerald R
GR
Marx
Steven D
SD
Colan
D000293:Adolescent; D000328:Adult; D001900:Boston / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D004452:Echocardiography / Q000706:statistics & numerical data*; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000401:mortality*; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D056830:Isolated Noncompaction of the Ventricular Myocardium / Q000000981:diagnostic imaging* / Q000401:mortality*; D008297:Male; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D016019:Survival Analysis; D015996:Survival Rate; D055815:Young Adult