captopril
TRANSCRIPT
CAPTOPRIL RENOGRAPHY INTHE EVALUATION OF HYPERTENSIVE PATIENTS
DR. V. SIVA SUBRAMANIYAN,
DEPT. OF NUCLEAR MEDICINE,
SSSIHMS, PRASHANTHIGRAM.
A I M S
I N C I D E N C E O F R.A.S
U T I L I T Y OF CAPTOPRIL
E F F E C T O F C A P T O P R I L O N H Y P E R T E N S I V E S
PATHOPHYSIOLOGY OF R.V.H
I N D I C A T I O N S
Accidental invention.
Majid et al 1983
Marked decreased renal uptake
in a patient taking Captopril.
On discontinuation recovery of
renal function.
D I S C O V E R Y
M E T H O D O L O GY
BETA – BLOCKERS AND ANTIHYPERTENSIVES TO BE STOPPED 48 – 72 HRS. BEFORE THE STUDY BASAL RENOGRAPHY TO BE PERFORMED. CLASSICAL CONVENTIONAL PROCEDURE TO BE FOLLOWED.
Tracer 99 Tc m – DTPA.
Dose : 3-5 mCi
Route : IV injection
Preparation : Proper hydration.
R E N A L S C I N T I G R A P H Y
M E T H O D O L O G Y25 – 50 mg CAPTOPRIL TABLETS TO
BE CRUSHED AND ADMINISTERED
ORALLY ALONG WITH 250 ml OF
WATER. 90min. LATER RENAL
SCINTIGRAPHY IS REPEATED WITH
TWICE THE DOSE OF TC 99 m DTPA
USED FOR BASE LINE.
I N T E R P R E T A T I O N
Image analysis
GFR estimation.
Renographic curve analysis
Captopril response
P O S I T I V E C R I T E R I A
Decrease in % of uptake by > 10%.
Reduction in GFR by > 10%
Worsening of renographic curves
Increased tracer retention
Increased transit time
R E N O G R A M T Y P E S
CAPTOPRIL RESPONSE
SSSIHMS PRASHANTIGRAM__________________________________________________________________
Name: Sudha Sree Purna. A Age / Sex: 37/F Hospital No: 53773/k2 Procedure: Captopril Renography Date: 19/08/02 N.M N0. RD /4658&63/2002 Tracer: Tc-99m DTPA Dose: 10 Mci Route: Intravenous Protocol: Gates Diuretic: Lasix 40 mg i.v Time: F 0 Hydration: plenty of oral fluid Clinical History: ? Renovasular Hypertension. Right Kidney small on Ultra Sound Scan. Renal Scan for functional assessment of the Kidneys. Procedure: After obtaining the Basal study Anti-hypertensives stopped for 2 days. Captopril 50 mg administered orally and after 3 hours Renogram study is repeated. IMAGES
INTERPRETATION K I D N E Y S C O R T E X Site Size Position Visualization Delineation Defect Contour RT. Normal Normal Normal Prompt Fair Nil Smooth LT. Normal Normal Normal Prompt Good Nil Smooth C O L L E C T I N G S Y S T E M U R E T E R Visualisn. Delineation Uptake late fill. Visualisn. Accumulation Insertion RT. Prompt Good Increased Nil Faint Trace Normal LT. Prompt Good Increased Nil Faint Trace Normal R E N O G R A P H I C C U R V E A N A L Y S I S PHASE: Uptake Secretory Excretory Diur.response G.F.R % Function Pre Post Pre Post Pre Post Pre Post Pre Post Pre Post RT. Vertical Verti Blunted Blunt. Step PlateauType I TypeIII 36 ml 32 ml 46 % 43 % LT. Vertical Verti Slope Slope Step Step Type I Type I 42 ml 43 ml 54 % 57 % TOTAL GFR Pre 78 Post 75 ml / min IMPRESSION: The Post Captopril Study reveals evidence of Decrease in the Rt. Kidney GFR with worsening of Curve pattern indicating the High Probabiliy of Rt. Renal Artery Stenosis. DR.V.SIVASUBRAMANIYAN, Consultant Nuclear Medicine Physician ___________________________________________________________________________________
CAPTOPRIL SERIES
Male : 16-68 yrs ; 36.4 +- 13.6 51
Female : 15-50 yrs ; 34.5 +- 8.9 17
Total 68
R E S U L T S
Positive : 11 / 68 16%
Negative : 57 / 68 84%
N E G A T I V E G R O U P
Males Females
Pre-capto 61 +- 25 ml/min
66 +- 28 ml/min
Post-capto 75 +- 29 ml/min
82 +- 30 ml/min
C O N T R A I N D I C A T I O N S
B I L A T E R A L R.A.S
DRUG STOPPAGE NOT POSSIBLE
IMPENDING RENAL FAILURE
Recent invention by
Imanishi et al. 1991
Substitute to Captopril.
A S P R I N R E N O G R A P H Y
P R O C E D U R E
Asprin - 20 mg / kg 130 mg
Oral administration
Renal scintigraphy one hour later.
P A T H O P H Y S I O L O G Y
Prostaglandin
Vasodilatation
Increases glomerular blood flow
Asprin blocks prostaglandin
Decrease in glomerular blood flow.
A D V A N T A G E S
No stopping of ACEI / Beta blockers.
No threat of HYPOTENSION.
No hazard of renal shutdown.
DISADVANTAGES
Positive in 57 % only.
Sub-groups specificity.
Selective insensitivity.
F L O W C H A R T
High risk hypertensive
Color duplex doppler sonography
Renal artery stenosis
Positive Equivocal Negative
Drug stoppage
Possible Not possible
PTRA Captopril Asprin Exr. renogram
C O N C L U S I O N
Difficult situations.
Definitive role.
Decision making.