Impaired myocardial blood flow and coronary flow reserve of the anatomical right systemic ventricle in patients with congenitally corrected transposition of the great arteries.
OBJECTIVE
To investigate myocardial blood flow of the morphological right systemic ventricle in unoperated patients with congenitally corrected transposition of the great arteries (CCTGA) by positron emission tomography (PET).


METHODS
Prospective cross sectional clinical study.


METHODS
Tertiary referral centre for paediatric cardiology.


METHODS
15 patients with CCTGA were investigated by PET with nitrogen-13 ammonia at rest and during adenosine vasodilatation. A subgroup of seven patients had isolated CCTGA (group A, mean (SD) age 30.3 (11.9) years) and the remaining eight patients had complex CCTGA associated with subpulmonary stenosis; four of this second group also had ventricular septal defect (group B, mean (SD) age 30.6 (16.4) years). Eleven healthy adults (mean (SD) age 26.2 (5.1) years) served as the control group.


RESULTS
Resting myocardial blood flow was not different between both groups of patients with CCTGA and the controls. Hyperaemic blood flows were significantly lower in both groups of CCTGA than in the control group (mean (SD) 195 (21) ml/100g/min in group A, 201 (27) ml/100g/min in group B, 309 (74) ml/100g/min in the control group; p < 0.001). Thus, coronary flow reserve was significantly lower in both groups of CCTGA than in the control group (mean (SD) 2.5 (0.28) in group A, 2.6 (0.48) in group B, and 4.0 (0.73) in the control group; p < 0.001).


CONCLUSIONS
Blood flow measurements suggest that coronary reserve is decreased in the absence of ischaemic symptoms in patients with CCTGA. The global impairment of stress flow dynamics may indicate altered global vasoreactivity, and quantitative changes in microcirculation suggest that their role in the pathogenesis of systemic right ventricular dysfunction is important.
Hauser
M
M
Deutsches Herzzentrum Munich, Technical University, Department of Paediatric Cardiology, Munich, Germany. hauser@dhm.mhn.de
Bengel
F M
FM
Hager
A
A
Kuehn
A
A
Nekolla
S G
SG
Kaemmerer
H
H
Schwaiger
M
M
Hess
J
J
D000241:Adenosine; D000293:Adolescent; D000328:Adult; D001783:Blood Flow Velocity; D001794:Blood Pressure / Q000502:physiology; D002648:Child; D003326:Coronary Circulation / Q000502:physiology*; D003327:Coronary Disease / Q000503:physiopathology*; D003331:Coronary Vessels / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014055:Tomography, Emission-Computed; D014188:Transposition of Great Vessels / Q000503:physiopathology* / Q000601:surgery; D014655:Vascular Resistance / Q000502:physiology; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents; D018497:Ventricular Dysfunction, Right / Q000503:physiopathology*
D014665:Vasodilator Agents; D000241:Adenosine