SIGNIFICANCE OF 24-H BLOOD-PRESSURE MONIT ORING IN THE DIAGNOSIS OF RENAL-ARTERY STENOSIS COMPARED WITH COLOR-CODED DUPLEX SONOGRAPHY AND RENAL ANGIOGRAPHY
Kl. Schulte et al., SIGNIFICANCE OF 24-H BLOOD-PRESSURE MONIT ORING IN THE DIAGNOSIS OF RENAL-ARTERY STENOSIS COMPARED WITH COLOR-CODED DUPLEX SONOGRAPHY AND RENAL ANGIOGRAPHY, Medizinische Klinik, 92(6), 1997, pp. 313-318
Background: Direct renal angiography is still the method of choice for
identification of renal artery stenosis. Newer non-invasive diagnosti
c methods include color coded duplex sonography and also ambulatory 24
-h blood pressure monitoring, since in a large proportion of patients
with secondary forms of hypertension the usual blood pressure fall dur
ing nighttime disappears. Patients and Methods: In a prospective in-ho
spital study we investigated 86 patients with suspected renovascular h
ypertension. Circadian blood pressure was measured oscillometrically a
nd color coded duplex sonography was performed immediately before dire
ct renal angiography. Results: Angiography revealed renal artery steno
sis (greater than or equal to 50%) in 42 patients. This compared to a
sensitivity of 92.9% and specifity of 91.7% for the use of sonography
in those patients (70.4%) who could be adequately examined. Mean 24-h
pressure values as well as standard deviations of blood pressure means
as an indicator for blood pressure variability were not different in
the 2 groups of patients, when all the data were analysed together and
also when the data for nighttime and daytime were examined separately
. The percent of blood pressure fall during nighttime was also not dif
ferent in the 2 groups. In both groups 4 hypertensive patients had a b
lood pressure increase during nighttime. In 11 patients without renal
artery stenosis a blood pressure fall of < 10% was observed, compared
to 12 patients with renal artery stenosis. The circadian pattern of pu
lse rate was similar in both groups. Conclusion: We conclude that ambu
latory blood pressure monitoring has a considerably lower diagnostic v
alue for renal artery stenosis compared to angiography and also to col
or coded duplex sonography. This method therefore does not appear to b
e an appropriate screening approach for this kind of secondary hyperte
nsion. The color coded duplex sonography, however, seems to be the bes
t non-invasive diagnostic method in those patients, who can be adequat
ely examined.