[MRI-based flow measurements in the main pulmonary artery to detect pulmonary arterial hypertension in patients with cystic fibrosis].
OBJECTIVE
Development of pulmonary arterial hypertension (PH) is a common problem in the course of patients suffering from cystic fibrosis (CF). This study was performed to evaluate MRI based flow measurements (MR(venc); Velocity ENCoding) to detect signs of an evolving PH in patients suffering from CF.


METHODS
48 patients (median age: 16 years, range: 10 - 40 years, 25 female) suffering from CF of different severity (mean FEV (1): 74% +/- 23, mean Shwachman-score: 63 +/- 10) were examined using MRI based flow measurements of the main pulmonary artery (MPA). Phase-contrast flash sequences (TR: 9.6 ms, TE: 2.5 ms, bandwidth: 1395 Hertz/Pixel) were utilized. Results were compared to an age- and sex-matched group of 48 healthy subjects. Analyzed flow data where: heart frequency (HF), cardiac output (HZV), acceleration time (AT), proportional acceleration time related to heart rate (ATr), mean systolic blood velocity (MFG), peak velocity (Peak), maximum fow (Fluss(max)), mean flow (Fluss(mitt)) and distensibility (Dist).


RESULTS
The comparison of means revealed significant differences only for MFG, Fluss(max) and Dist, but overlap was marked. However, using a scatter-plot of AT versus MFG, it was possible to identify five CF-patients demonstrating definite signs of PH: AT = 81 ms +/- 14, MFG = 46 +/- 11 cm/s, Dist = 41% +/- 7. These CF-patients where the most severely affected in the investigated group, two of them were listed for complete heart and lung transplantation. The comparison of this subgroup and the remaining CF-patients revealed a highly significant difference for the AT (p = 0.000001) without overlap.


CONCLUSIONS
Screening of CF-patients for the development of PH using MRvenc of the MPA is not possible. In later stages of disease, the quantification of AT, MFG and Dist in the MPA may be useful for the detection, follow-up and control of therapy of PH. MR(venc) of the MPA completes the MRI-based follow-up of lung parenchyma damage in patients suffering from CF.
Wolf
T
T
OncoRay, Biologisches und Molekulares Imaging, TU Dresden.
Anjorin
A
A
Posselt
H
H
Smaczny
C
C
Vogl
T J
TJ
Abolmaali
N
N
D000293:Adolescent; D000328:Adult; D003550:Cystic Fibrosis / Q000150:complications / Q000175:diagnosis*; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011651:Pulmonary Artery / Q000473:pathology*; D015203:Reproducibility of Results; D012212:Rheology / Q000379:methods*; D012680:Sensitivity and Specificity; D055815:Young Adult