renal stenting and denervation - prof. tadeusz przewłocki
TRANSCRIPT
Current status and future perspectives of renal Current status and future perspectives of renal stenting and renal denervation:stenting and renal denervation:
Who is still indications for renal arteries stenting?Who is still indications for renal arteries stenting?
Tadeusz PrzewłockiTadeusz Przewłocki
PINC in Kraków 1411th Peripheral Interventions Workshop
8-9 May 2014
Institute of Cardiology – Collegium Medicum,Jagiellonian University, John Paul II Hospital
Kraków
Renal artery stenosis (RAS)-frequencyRenal artery stenosis (RAS)-frequency
PAOD patientsPAOD patients30 – 45 %30 – 45 %
Harding et al.J Am Soc Nephrol 1992, 2, 1608Harding et al.J Am Soc Nephrol 1992, 2, 1608Olin et al.. Am J Med. 1990, 88, 46Olin et al.. Am J Med. 1990, 88, 46
General populationGeneral population0,1 – 1 %0,1 – 1 %
Hypertensive patients Hypertensive patients 2 – 5 %2 – 5 %
CAD patientsCAD patients10 – 34 %10 – 34 %
Hypertensive patients with renal insufficiency
30 – 40 %
RAS – renal ischemia, RAA- activationRAS – renal ischemia, RAA- activationConsequencesConsequences- - HA, LV hypertrophy, vascular HA, LV hypertrophy, vascular
remodeling, accelerated atherosclerosis remodeling, accelerated atherosclerosis
Heart failureHeart failure Pulmonary oedema Pulmonary oedema
nephropathynephropathy ESRDESRD
strokestroke CAD – MI , UACAD – MI , UA aortic dissectionaortic dissection
cardiaccardiac
renalrenal
vascularvascular
The impact of RAS on survivalThe impact of RAS on survival
Goals for renal revascularization in RAS patients
1. Preservation of renal function2. Improved blood pressure control3. Prevention of CHF or angina pectoris
Survival improvementQOL improvement
Kaltra P, Zeller T. - Salford & Bad Krozingen – 220 chKaltra P, Zeller T. - Salford & Bad Krozingen – 220 ch
Balloon PTA Stenting
EMMA
SNRASCG
DRASTIC
ASTRAL
STAR
ASPIRE 2
RENAISSANCERENAISSANCE
RAS vs BMT – results of randomized trials
No difference
Better hypertension control
CORAL
8 randomized trialsonly 2 positive (in respect of hypertension)
What is „significant renal artery stenosis”?
Physiological stenosis assessment
How to explain discrepancy between observationalinvestigations and randomized trials?
Rest Pd/Pa ratio <0,90 is assoc. with increasedrenin production
Ratio is more import.than gradient alone
Gradient of the systolic blood pressure over 20 mmHg and over 10 mmHg of the mean blood pressure impacts on the physiology of renal blood flow
Renal Fractional Flow Reserve (RFFR)Renal Fractional Flow Reserve (RFFR)
RFFR = Qmax stenosis / Qmax normal
Qmax normal = (Pa-Pv)/ R
Qmax stenosis = (Pd-Pv)/ R
Measurements must be taken at maximal hyperemia.
Pa = Mean aortic pressure
Pd = Mean pressure distal to stenosis
Pv = Mean central venous pressure
Qmax normal = Maximum renal blood flow in the absence of stenosis
Qmax stenosis = Maximum renal blood flow in the presence of stenosis
R = Renal arteriolar vascular resistance at maximum hyperemia
Renal arterial bed dilators
NTG – 0,3 – 1 mg – intrarenally (Gross, Beregi) RBF mean increase 40%
Papaverine – 8 – 40 mg intrarenally (Subramanian, De Bruyne)RBF mean increase 50%
Dopamine – 50ug/kg – intrarenally (De Bruyne) RBF mean increase 95%
In contrast to coronary arteries best renal dilators occureddopamine De Bruyne at al.
FFR Guided Renal Angioplasty
Mean Hyperemic GradientMean Hyperemic GradientR
esp
on
de
rs %
>20m
m H
g
<20m
m H
g0
100
Hyperemic mean gradient >20mmHg (dopamine) independent predictor of blood pressure control improvement after RAS
Blood Pressure RespondersBlood Pressure RespondersImprovement: BP < 140/90 mmHg, or a decrease of DBP by 15 mm Hg on the same or reduced # of medications.
< .80RFFR<0,80
In summary it seems we have two ways of physiological stenosis assessment:
Gradient - across the lesion – resting or hyperemic>20 mmHg(De Bruyne, Massoud, Trana),
Pd/Pa ratio - resting - <0,9 (De Bruyne)hyperemic (RFFR)<0,8 (Mitchell, De
Bruyne,),
Renal FFR of <0.80 predicts an increased Renal FFR of <0.80 predicts an increased
likelihood of BP response.likelihood of BP response.
Renal artery stenosis – criteria for interventionRenal artery stenosis – criteria for intervention
Clinical arterial hypertension(IIa)-resistant, malignant, accelerated failed 3 drugs in max dose
renal dysfunction - severe, progressive – bilateral stenosis solitaire kidney (IIa), unilateral stenosis (IIb)heart failure-unexpected recurrent pulmonary oedema (IC)CAD - recurrent instability episodes (IIa)
Anatomic
stenosis >70 % diameter stenosis or >85 % area reduction - 50-70 % with a peak gradient >20 mmHg
- RFFR<0,80renal length difference ł 1,5 cm or documented decrease > 1 cm
but renal length should be > 7,5 cm