Ventricular performance before and after Fontan repair for univentricular atrioventricular connection: angiographic and radionuclide assessment.
OBJECTIVE
This study was designed to evaluate changes in ventricular volume, mass and cardiac function before and after creation of an atrial to pulmonary connection in patients with a univentricular atrioventricular connection.


BACKGROUND
Intact systolic and diastolic performance is critical for successful establishment of an atrial dependent circulation, and few studies are available comparing cardiac performance before and after creation.


METHODS
With the use of radionuclide blood pool imaging and ventricular cineangiography, 54 patients (mean age 6.4 +/- 3.4 years) were studied. Twenty-eight patients were investigated preoperatively and 36 greater than 1 year after repair and compared with a control population.


RESULTS
Before operation, end-diastolic volume and wall mass were significantly increased compared with those of control subjects; however, the mass/volume ratio was normal (1.08 +/- 0.31 g/ml for the preoperative group; 0.97 +/- 0.19 for control subjects). Although end-diastolic volume returned to normal after the procedure, wall mass remained elevated and contributed to an elevated mass/volume ratio (1.20 +/- 0.38 g/ml). After the procedure, systemic vascular resistance index was significantly elevated compared with that before surgery or with that of control subjects (1,199 +/- 373, 2,120 +/- 645, 1,556 +/- 275 dynes.s.cm-5.m2: pre- and postrepair and control subjects, respectively). Radionuclide studies demonstrated that preoperative ejection fraction (52 +/- 9, 50 +/- 9, 60 +/- 8%), peak ejection (2.58 +/- 0.66, 2.95 +/- 0.81, 3.73 +/- 0.70 EDV/s) and peak filling rates (2.84 +/- 0.75, 2.75 +/- 0.79, 3.84 +/- 0.51 end-diastolic volumes [EDV/s]) were significantly reduced compared with those of control subjects and remained so after surgery.


CONCLUSIONS
These data suggest that systolic and diastolic function is depressed preoperatively in these patients, remains unchanged after the creation of an atrial-dependent circulation and is associated with an increased systemic vascular resistance. Long-term issues addressing preservation of cardiac function need to be prospectively studied.
Akagi
T
T
Department of Pediatrics, Hospital for Sick Children, Toronto, Ontario, Canada.
Benson
L N
LN
Green
M
M
Ash
J
J
Gilday
D L
DL
Williams
W G
WG
Freedom
R M
RM
D002648:Child; D002932:Cineangiography; D005260:Female; D015637:Gated Blood-Pool Imaging; D006321:Heart / Q000000981:diagnostic imaging; D006325:Heart Atria / Q000601:surgery*; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D006352:Heart Ventricles / Q000002:abnormalities; D006801:Humans; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology*; D011651:Pulmonary Artery / Q000601:surgery*; D014655:Vascular Resistance / Q000502:physiology; D016276:Ventricular Function / Q000502:physiology*