Left ventricular morphology influences mortality after the Norwood operation.
BACKGROUND
Within the spectrum of congenital heart disease referred to as hypoplastic left heart syndrome (HLHS), there is variation in the morphology and function of the left ventricle which could influence outcomes after stage I Norwood palliation.


OBJECTIVE
To determine if left ventricular (LV) morphology is associated with outcome after stage I Norwood palliation for HLHS.


METHODS
Echocardiograms were reviewed from 108 patients who had undergone Norwood palliation at our institution over the past 11 years. Total cardiac diameter, thickness of the interventricular septum (IVS), LV area and LV myocardial area were calculated. Competing risk analysis was performed for survival to a stage II operation and to determine potential predictors.


RESULTS
From the Norwood operation up to stage II operation, mortality was predicted by IVS thickness, while the absence of right ventricular (RV) dysfunction was predictive of survival to stage II operation. For the complete pathway, from Norwood to the Fontan operation, mortality was predicted by IVS, a lower RV fractional area change and the presence of significant tricuspid regurgitation. Cardiac transplantation during this period was predicted by a lower RV fractional area change (p = 0.02) and a larger LV area in diastole.


CONCLUSIONS
These results indicate that LV hypertrophy and decreased RV function adversely effect survival after the Norwood operation. They suggest that LV morphology, especially septal hypertrophy, can influence outcomes in HLHS and should be considered when evaluating treatment options.
Walsh
M A
MA
Division of Cardiac Critical Care Medicine, Hospital for Sick Children, 555 University Ave, Toronto, ON M5G 1X8, Canada.
McCrindle
B W
BW
Dipchand
A
A
Manlhiot
C
C
Hickey
E
E
Caldarone
C A
CA
Van Arsdell
G S
GS
Schwartz
S M
SM
D005260:Female; D016027:Heart Transplantation / Q000401:mortality / Q000706:statistics & numerical data; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011788:Quality of Life; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis