Twenty-one patients were included in the study. The mean age was 40.3 years old (26 - 64 yo). There were 14 women and 7 men corresponding to man-to-woman sex ratio of 1:2. In the right renal artery (RRA), the mean peak systolic velocity (cm/s) was 67.85, 66.46 and 42.08 respectively at the ostium, trunk and hilum. In the left renal artery (LRA), the mean PSV were 80.10, 50.90 and 40.13 respectively at the ostium, trunk and hilum. Regarding the resistance index, the mean values in the RRA were 0.67 at the ostium, 0.66 at the trunk and 0.61 at the hilum. The same parameters in the LRA were respectively 0.66, 0.64 and 0.57. The mean acceleration time (ms) in the RRA was 56.76 at the trunk and 65.85 at the hilum. The measurements of the same parameters in the LRA were respectively 56.39 and 50.18. The DU was normal in 17 patients (80.9%); it was not affirmative in 3 patients (14.3%) and SRA was diagnosed in 1 patient (4.8%). Overall, the DU of the RA was efficient in 18 patients; this corresponds to a sensitivity of 85.7%.

1. Doppler Ultrasound of the Renal Arteries in Hypertensive Patients in Senegal: A cross-sectional study of 21 patients
IJCCR
Doppler Ultrasound of the Renal Arteries in Hypertensive
Patients in Senegal: A cross-sectional study of 21
patients
El Hadji Mbacké Sarr1, Adama Sawadogo2*, Mohamed Leye3, Momar Dioum1, Kadia Ba1,
Dominique Bindia1, Arame Diagne Diallo1, Magalie Kaya1, Simon Manga1, Ibrahima Bara Diop1
1Department of cardiology, Cheikh Anta Diop University of Dakar, Senegal
2Department of cardiovascular and thoracic surgery, Cheikh Anta Diop University, Senegal
3Unit of training and research in medical sciences, University of Thies, Senegal
Twenty-one patients were included in the study. The mean age was 40.3 years old (26 - 64 yo).
There were 14 women and 7 men corresponding to man-to-woman sex ratio of 1:2. In the right
renal artery (RRA), the mean peak systolic velocity (cm/s) was 67.85, 66.46 and 42.08 respectively
at the ostium, trunk and hilum. In the left renal artery (LRA), the mean PSV were 80.10, 50.90 and
40.13 respectively at the ostium, trunk and hilum. Regarding the resistance index, the mean values
in the RRA were 0.67 at the ostium, 0.66 at the trunk and 0.61 at the hilum. The same parameters
in the LRA were respectively 0.66, 0.64 and 0.57. The mean acceleration time (ms) in the RRA was
56.76 at the trunk and 65.85 at the hilum. The measurements of the same parameters in the LRA
were respectively 56.39 and 50.18. The DU was normal in 17 patients (80.9%); it was not affirmative
in 3 patients (14.3%) and SRA was diagnosed in 1 patient (4.8%). Overall, the DU of the RA was
efficient in 18 patients; this corresponds to a sensitivity of 85.7%.
Keywords: Doppler Ultrasound, renovascular hypertension, renal artery stenosis, Senegal.
INTRODUCTION
Doppler ultrasound (DU) is a non-invasive imaging
modality that has been used to diagnose stenosis of renal
artery (SRA) in hypertensive patients (Abuagla 2014).It
combines a direct visualization of the RA (B mode) with the
measurement of various hemodynamic factors in the main
and intra-parenchymal RA (Doppler). Thus it allows
anatomical and functional reno-vascular evaluation
(Jenderka 2015); (Rinehardt 2014). There are many
clinical situations in which a SRA should be considered.
These situations include: hypertension in patient > 55
years old or under < 30 years old with recent aggravation
and that is clinically severe (> 180/110 mm Hg); associated
with hypokalemia or with a significant decrease in blood
pressure due to an angiotensin converting enzyme (ACE)
inhibitor` or an angiotensin receptor blocker (ARB) (Ifergan
2011). In this work we report our experience on the
contribution of the DU in the diagnosis of the etiologies of
hypertension in Dakar, Senegal.
*Corresponding author: Dr. Adama Sawadogo, MD.
Department of cardiovascular and thoracic surgery,
Cheikh Anta Diop University, Senegal. Email:
adamsaw2000@yahoo.fr Tel : +226 70104922
Co-authors: Dr. El Hadji Mbacké Sarr, MD. Email:
elhadjimbackesarr@gmail.com Tel: +221 776350815
Dr Mohamed Leye, MD. Email: leyemohamed@gmail.com
Tel: +221 771667088.
International Journal of Cardiology and Cardiovascular Research
Vol. 3(1), pp. 031-036, June, 2017. © www.premierpublishers.org, ISSN: 2146-3133
Research article

2. Doppler Ultrasound of the Renal Arteries in Hypertensive Patients in Senegal: A cross-sectional study of 21 patients
Sawadogo et al. 032
MATERIALS AND METHODS
It consisted of cross-sectional and descriptive study of all
the hypertensive patients who underwent DU of the RA at
the department of Cardiology of the University Hospital of
Fann, Dakar in Senegal. The criteria of inclusion were
young age, important to severe increase in blood pressure
and hypertension refractory to conventional treatment. The
study was conducted from February 1, 2013 to February
28, 2017. The Doppler was performed by one operator
who used a low frequency convex abdominal probe (2 to 5
MHz) coupled to a pulsed Doppler from 2 to 3.5 MHzin
color coding. Microsoft Access and Excel (Microsoft
Corporation) were used to create the database. IBM
SPSS
Statistics Version 22 was used to analyze statistics
Means and 95% confidence intervals were calculated. In
four years, 21 cases were involved in the study. The
studied criteria were age, sex, aortic systolic velocity
(ASV), Peak Systolic Velocity (MSV) of the RA at the
ostium, trunk and hilum. The other assessed parameters
were vascular resistance index (RI) and acceleration time
(AT). The aspect of the renal parenchyma was also
described.
RESULTS
Age and sex
The mean age of the patients was 40.31 ± 1.35 years old
ranging between 26 and 64 years old. There were 14
women and 7 men corresponding to man-to-woman sex
ratio of 1:2.
At the ostia of the renal arteries
On the right, the mean PSV was 67.85 ± 29.57 cm/s with
extremes of 53.9 and 131.2 cm/s; the average RI was 0.67
± 0.07 ranging from 0.48 to 0.75.
On the left, the mean PSV was 80.10 ± 75.38cm/s with a
minimum of 38.8 and a maximum of 302 cm/s; the mean
IR was 0.66 ± 0.13 for values ranging between 0.4 and
0.88.
At the main renal arteries (trunk)
On the right, the mean PSV was 66.46 ± 40.47 cm/s for
values ranging between 13.8 and 146.5 cm/s; the average
RI was 0.66 ± 0.11 for values ranging between 0.3 and
0.82. The mean AT was 56.76 ± 47.16ms with extremes of
30 and 254 ms.
At the left, the mean PSV was 50.90 ± 32.19cm/s for
values ranging between 0.41 and 109 cm/s; the average
RI was 0.64 ±0.10 for values ranging between 0.53 and
0.82. The mean AT was 56.39 ± 33.55ms with extremes of
30 and 191ms.
At the hilum of the renal arteries
On the right, the mean PSV was 42.08 ± 21.88cm/s for
values ranging between 13.8 and 105 cm/s; the average
RI was 0.61 ± 0.09with values in the range of 0.39 to 0.79.
The mean AT was 65.85 ± 49.04ms with extremes of 30
and 273 ms.
On the left the mean PSV was 40.13 ±15.86 cm/s for
values ranging between 20 and 59 cm/s; it was not
assessed in 6 cases (28.6%) because of bad conditions of
examination. The average RI was 0.57 ±0.07with values
ranging between 0.39 and 0.61. The conditions did not
allow assessing it in 5 cases (28.3%). The mean AT was
50.18 ± 36.50ms with extremes of 30 and 183 ms; its
evaluation was impossible in 5 patients (28.3%) in the
renal parenchyma.
The kidneys
Apart from of one patient, all had kidneys with normal
morphology with good corticomedullary differentiation; the
intra-parenchymal flow was normal. The size of the
kidneys varied between 8.46 and 12.5 cm on the right. On
the left it varied between 8.22 and 12.38 cm. This
corresponded to mean size 10.49 ± 1.31cm on the right
and 10.55 ± 1.16cm on the left.
Overview
Overall (Tables 1 and 2), one case of significant ostial RAS
(4.76%) was detected (Figures 1 and 2). The PSV of the
stenotic RA was 302 cm/s. In 3 patients (19%), the DU was
not affirmative and then an angio CT was prescribed. It
confirmed this lesion
DISCUSSION
Hypertension has become a public health problem in
Dakar. Indeed, according to a study carried out in 2014
(Macia, 2014), more than 1 in 4 adults (27.5%) were
affected. There was male predominance and the patients
were young (mean age 36 years). Yet, the average age
was higher in our series (40.31 years old) and 2/3 of the
patients were female. This is because the majority of our
patients had a profile that suspected a renovascular origin
of their hypertension and that justified seeking renal
arterial abnormality. Nevertheless, the epidemiological
results corroborate those of the series regarding arterial
stenosis (Safian 2001). The research of renal arterial
pathology is guided by the clinic; only stenosis greater than
60% of the lumen is significant and can be detected by the
DU (Lee 2002); (Qin 2011).The first step of the DU of the
RA is morphological. This measures the large axis of the
kidneys which is between 10 and 12 cm. Renal atrophy is
characterized by an axis diameter less than 8 cm (Macia
2014). Corticomedullary differentiation is then assessed.

3. Doppler Ultrasound of the Renal Arteries in Hypertensive Patients in Senegal: A cross-sectional study of 21 patients
Int. J. Cardiol. Cardiovasc. Res. 033
Table 1: Overview of the data set
Pat A S AFV
Right kidney Left kidney
CommentsOstium RRA Trunk RRA Hilum RRA Size Ostium
LRA
Trunk LRA Hilum LRA Size
PSV RI PSV RI AT PSV RI AT PSV RI PSV RI AT PSV RI AT
1 46 M 0,8 131,2 0,7 146,5 0,73 70 54,9 0,69 60 8,46 75,9 0,67 26,1 0,71 50 - - - 8,22 Normal
2 36 F 0,8 57,6 0,72 50 0,66 50 34,5 0,54 50 11,59 57,6 0,7 35,4 0,66 50 - - - 11,59 Normal
3 64 F 0,51 89,6 0,75 69 0,65 60 35 0,70 30 9,51 79 0,76 46 0,67 60 - - - 10,23 Normal
4 - M 0,4 67,6 0,48 56 0,49 50 24,8 0,59 50 9,98 57,6 0,62 46 0,68 30 35 0,49 30 12,05 Normal
5 59 F 0,6 55 0,75 29,6 0,75 30 69,7 0,61 55 9,98 57,5 0,78 79,8 0,80 30 59 0,60 40 10,41 Normal
6 63 M 0,49 55 0,75 29,6 0,75 30 69,7 0,61 55 9,98 57,7 0,78 79,8 0,80 30 59 0,60 40 10,41 Normal
7 - M 0,61 55 0,75 50,6 0,74 30 40,3 0,67 30 12,04 47,6 0,7 48,7 0,68 50 57,6 0,76 30 9,77 Bad CMD
8 36 F 0,59 61,4 0,65 46,8 0,66 30 47,4 0,56 40 12,5 47,6 0,7 41,2 0,58 60 31,3 0,49 30 9,77 Normal
9 26 M 0,59 56,4 0,63 40,8 0,6 50 27,1 0,59 60 9,9 43,1 0,61 59,7 0,62 61,9 28,9 0,61 40 8,9 Normal
10 41 M 0,74 22,1 0,57 13,8 0,63 30 13,8 0,56 60 9,78 54,6 0,55 34,8 0,57 20 20 0,55 50 10,79 Normal
11 41 F 0,74 53,9 0,57 96,4 0,61 30 24,4 0,49 90 9,5 49,6 0,5 50 0,53 40 39,5 0,56 60 12,38 Angio CT
12 39 F 0,83 53,9 0,57 96,4 0,61 38 24,4 0,49 50 9,14 49,6 0,5 50 0,53 40 39,5 0,56 60 12,38 Normal
13 26 F 0,3 53,9 0,57 60 0,3 254 30,5 0,39 273 9,14 38,8 0,41 36,6 0,36 191 39,5 0,39 183 10,8 Angio CT
14 38 M 1,40 56,4 0,71 40,8 0,69 50 27,1 0,59 60 10,5 43,1 0,66 59,7 0,62 61,9 28,9 0,61 40 10,9 Normal
15 40 F 1,63 56,4 0,71 106 0,82 50 105 0,79 60 10,7 110 0,88 106 0,82 61,9 77,1 0,61 40 10,9 Normal
16 33 F 0,97 - - 48 0,82 50 64 0,79 60 10,7 59 0,88 50 0,62 61,9 - 0,61 40 11,4 Angio CT
17 29 F 0,53 56,4 0,71 40,8 0,67 50 27,1 0,59 60 12,5 50 0,66 0,41 0,62 61,9 28,9 0,61 40 9,5 Normal
18 26 F 0,53 56,4 0,71 40,8 0,67 50 27,1 0,59 60 12,5 50 0,66 0,41 0,62 61,9 28,9 0,61 40 9,5 Normal
19 35 F 0,53 56,4 0,71 40,8 0,67 50 27,1 0,59 60 11,5 50 0,4 0,41 0,62 61,9 28,9 0,61 40 11,3 Normal
20 58 F 0,8 131,2 0,7 146,5 0,73 70 54,9 0,69 60 12 302 0,79 109 0,71 50 - - - 11 SRA
21 30 F 0,8 131,2 0,7 146,5 0,73 70 54,9 0,69 60 8,5 302 0,79 109 0,71 50 - - - 9,4 Normal
Legends: Pat (patient); A (age); S (sex); F (female); M (Male); AFV (aortic flow velocity); RRA (right renal artery); LRA (left renal artery) PSV (peak systolic velocity); RI (resistance index); AT
(acceleration time); CMD (corticomedullarydifferention); SRA (stenosis of renal artery)

4. Doppler Ultrasound of the Renal Arteries in Hypertensive Patients in Senegal: A cross-sectional study of 21 patients
Sawadogo et al. 034
Table 2: Analysis of basic parameters (n=21)
Variables Minimum Maximum Mean Standard Deviation
Age (yearsold) 26 64 40.31 1.35
Aortic flow velocity (m/s) 0.3 1.63 0.72 0.31
Right kidney
Size (mm) 8.46 12.5 10.49 1.31
PSV (cm/s)
Ostium 53.9 131.2 67.85 29.57
Trunk 13.8 146.5 66.46 40.47
Hilum 13.8 105 42.08 21.88
RI
Ostium 0.48 0.75 0.67 0.07
Trunk 0.3 0.82 0.66 0.11
Hilum 0.39 0.79 0.61 0.09
AT (ms) Trunk 30 254 56.76 47.16
Hilum 30 273 65.85 49.04
Leftkidney
Size 8.22 12.38 10.55 1.16
PSV (cm/s)
Ostium 38.8 302 80.10 75.38
Trunk 0.41 109 50.90 32.19
Hilum 20 59 40.13 15.86
RI
Ostium 0.4 0.88 0.66 0.13
Trunk 0.53 0.82 0.64 0.10
Hilum 0.39 0.61 0.57 0.07
AT (ms) Trunk 30 254 56.39 33.55
Hilum 30 103 50.18 36.50
Legends: PSV (Peak Systolic Velocity), RI (Resistance Index), AT (Acceleration Time)
Figure 1: Doppler ultrasound showing the stenosis of left renal artery.
Figure 2 : Peak systolicvelocity > 180 ms
LeftKidney Stenotic LRA
Aorta

5. Doppler Ultrasound of the Renal Arteries in Hypertensive Patients in Senegal: A cross-sectional study of 21 patients
Int. J. Cardiol. Cardiovasc. Res. 035
In our series, no patient had atrophic kidney, but there was
only one case of unclear corticomedullary differentiation.
There were no other suspicious parenchymal images. The
renal arteries were examined at the ostium, the trunk, the
hilum and in the intra-parenchymal part. Conventionally, a
PSV ≥ 200 cm/s and a reno-aortic ratio (PSV /
aorticsystolic velocity) ≥ 3.5 define a stenosis ≥ 60% with
a sensitivity and specificity of 98% (Macia 2014). Of our 21
patients, only 1 showed this: a left ostial PSV of 302 cm/s,
an aortic flow at 0.8 m/s, and a reno-aortic ratio of 3.77.
The same patient (4.76%) presented all ultrasonographic
criteria of an ostial stenosis of the LRA. Renal vascular
resistance index (RI = (peak systolic velocity – end of
diastole velocity) / systolic renal velocity) is a noninvasive
method of description of intramuscular hemodynamic
changes (Lerolle 2009). The normal values usually range
0.5 and 0.7 (Tublin 2003). Most of the patients in our series
in had normal RI; the case of RAS had a RI of 0.71. Above
all, the RI has therapeutic interest. Indeed, a RI greater
than 0.80 reliably identifies patients with renal artery
stenosis in whom angioplasty or surgery cannot improve
the renal function, the level of blood pressure or the renal
survival (Radermache 2001).The average PSV was less
than 50 on the left and less than 40 on the right. In general,
DU shows an increase in the AT (AT> 70 ms) in
hemodynamically significant stenosis (Stephan 2007);
(Hélénon 2008). However, it must be associated with the
other parameters in order to define a stenosis (Ifergan
2011). In our case of RAS, the AT could not be assessed
at the hilum. But we combined the other criteria we could
see that the stenosis was evident. Overall in 21 cases, the
DU was sufficient and affirmative for the renovascular
analysis in 18 cases corresponding to a sensitivity of
85.7%. This corroborates the results of other series such
as those of Kawarada et al. who found sensitivity and
specificity greater than 89% (Kawarada 2006). Finally, the
specificity of the DU was enhanced in our series by the
confirmation of the stenosis by the angio CT. More
interestingly, because of normal level of RI we indicated to
re-vascularize the left renal artery by stenting.
CONCLUSION
Doppler ultrasound of the renal arteries is a
complementary examination that is cheaper, non-invasive
and of good sensitivity. It is feasible in our context and can
be popularized in case of hypertension and all clinical
situations that require renovascular assessment. It is an
excellent means for the therapeutic prognosis of renal
arterial lesions.
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6. Doppler Ultrasound of the Renal Arteries in Hypertensive Patients in Senegal: A cross-sectional study of 21 patients
Sawadogo et al. 036
Accepted 13 June, 2017
Citation: Sarr EM, Sawadogo A, Leye M, Dioum M, Ba K,
Bindia D, Diallo AD, Kaya M, Manga S, Diop IB (2017).
Doppler Ultrasound of the Renal Arteries in Hypertensive
Patients in Senegal: A cross-sectional study of 21 patients.
International Journal of Cardiology and Cardiovascular
Research, 3(1): 031-036.
Copyright: © 2017. Sarr EM, Sawadogo A et al. This is an
open-access article distributed under the terms of the
Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any
medium, provided the original author and source are cited.