Angiotensin Receptor Blockade: Applications to Clincal Care Timothy A. Denton, M.D. Divisions of Cardiology and Cardiothoracic Surgery Cedars-Sinai Medical Center Los Angeles
Jan 02, 2016
Angiotensin Receptor Blockade:
Applications to Clincal Care
Timothy A. Denton, M.D.Divisions of Cardiology and
Cardiothoracic SurgeryCedars-Sinai Medical Center
Los Angeles
Outline
• JNC VI• “Undertreatment”• Physiology• HTN drugs• ARB’s
JNC VI
JNC VI
Joint National Committee onPrevention, Detection, Evaluation,
and Treatment ofHigh Blood Pressure
JNC VI -- Arch Int Med 1997;157:2413
Why do we need blood pressure?
Why do we need blood pressure?
• Get blood to the scalp• Distribute flow quickly
Category Systolic Diastolic
Optimal <120 <80
Normal <130 <85
High-normal 130-139 85-89
Hypertension
Stage I 140-159 90-99
Stage II 160-179 100-109
Stage III >180 >110
Classification of HTN
JNC VI -- Arch Int Med 157:2413, 1997
Category Risk factors Target OrganDamage
CV Disease
Group A 0 0 0
Group B >1 (not DM) 0 0
Group C >1 or DM + +
Risk Classification
JNC VI -- Arch Int Med 157:2413, 1997
Category Group A Group B Group C
High-normal Lifestyle Lifestyle Drugs
Stage I Lifestyle Lifestyle (6 mo) Drugs
Stages II, III Drugs Drugs Drugs
Approach to HTN Therapy
JNC VI -- Arch Int Med 157:2413, 1997
Etiology of HTN
•RenalChronic pyelonephritisGlomerulonephritisPolycystic kidneyRenovascularOther renal
•EndocrineOral contraceptivesAdrenocortical (Cushing, hyperaldo,
17 hydroxylase, 11-hydroxylase)PheochromocytomaMyxedemaAcromegaly
Normal Pulse Pressure•Neurogenic
PsychogenicFamilial dysautonomiaPolyneuritisIncreased intracranial pressureSpinal cord section
•MiscCoarctationIntravascular volumePolyarteritis nodosaHypercalcemiaAcute intermittent porphyriaPre-eclampsia
Etiology of HTN
•Decreased aortic compliance•Increased stroke volume
AIThyrotoxicosisHyperkinetic heart syndromeFeverAV fistula / PDA
Wide Pulse Pressure
Physiology of HTN
Primary Hypertension•? central/peripheral adrenergic•? renal•? hormonal•? vascular
Physiology of HTN
Secondary• Wide Pulse Pressure
Aortic complianceStroke volume
•Normal Pulse PressureRenalEndocrineNeurogenicMisc
Epidemiology of HTNDiagnosis % Population
PrimaryRenal Parenchymal RenovascularEndocrine Primary aldo Cushing’s Pheo Oral contraceptiveMisc
92-94
2-31-2
0.3<0.1<0.12-40.2
Harrison’s Principles of Internal Medicine, 12th Edition
Classes of Anti-Hypertensives(1999 PDR)
Adrenergic blockersAlpha/Beta adrenergic blockersACE inhibitorsACE + Ca blockersACE + diureticsARB’sARB’s with diureticsBeta blockersBeta blockers with diureticsCalcium blockersDiureticsRauwolfia derivativesVasodilators
Preparations of Anti-Hypertensives by Class(1999 PDR)
Adrenergic blockersAlpha/Beta adrenergic blockersACE inhibitorsACE + Ca blockersACE + diureticsARB’sARB’s with diureticsBeta blockersBeta blockers with diureticsCalcium blockersDiureticsRauwolfia derivativesVasodilators
65
114542
156
25242
18
Total = 127
Special Considerations
In African-Americans: -- low probability of success with Beta blockers or ACE
or ARB’s
-- higher probability of success with diuretics or Ca blockers
Compelling Indications
Condition RecommendedTherapy
DM (type 1) + proteinuria ACE
CHF (low EF) ACE, diuretics
Sys HTN diuretics, Ca blockers
MI beta blockers, ACE
JNC VI -- Arch Int Med 157:2413, 1997
“The committee recognizes thatthe responsible clinician’sjudgment of the individual
patient’s needs remains paramount.”
JNC VI -- Arch Int Med 1997;157:2413
Undertreatment
National Data on HTN
51
73
31
55
10
29
0
10
20
30
40
50
60
70
80
90
100
NHANES II NHANES III
National Health and Nutrition Examination SurveyII - 1976-1989, III - 1988-1991
Per
cen
t Aware HTN
Rx HTN
HTN Goal
Undertreatment of Hypertension
Percentage of Patients withBP > 160/90
46.339.4
0102030405060708090
100
Index 2 years
Office Visit
Pe
rce
nt
Berlowitz, NEJM 1998;339:1957
Undertreatment of Hypertension
Percentage of Patients with BP "controlled"
60.6
25
0102030405060708090
100
<160/90 <140/90
Threshold for "control"
Pe
rce
nt
Berlowitz, NEJM 1998;339:1957
Undertreatment of Hypertension
Increases in HTN Therapy
35
3.2
0102030405060708090
100
DBP>90 <90, <165
BP Findings
Pe
rce
nt
Berlowitz, NEJM 1998;339:1957
If you have not achieved goal,
you must change your therapy
You push a medication’s doseto EFFECT
or SIDE EFFECTor maximal recommended dose
Drug Suboptimal Optimal
losartan 50 mg qd 100 mg qd
metoprolol 50 mg qd 0 mg qd
HCTZ 12.5 mg qd 0 mg qd
Patient Example
Combination Drugs:A Different Animal
• Beta blocker + diuretic• ACE + diuretic• ACE + calcium blocker• ARB + diuretic• Diuretic + diuretic• “other” + diuretic
Pressure/Volume Relation
Pressure = 150 mmHg
FluidFlux
Pressure = 120 mmHg
FluidFlux
Vasculature
Physiology
Goodfriend TL, New Engl J Med 1996 334(25):1649-54
Goodfriend TL, New Engl J Med 1996 334(25):1649-54
Angiotensinogen
Angiotensin I
Angiotensin II
ReninInhibitor
ACEInhibitor
AT1 receptorInhibitor
Renin
ACE
Endothelin-1
Vasopressin
Vaso-constriction
Vaso-dilatation
Adapted, Bonn, D. Lancet 1998;352:378
non-ACEalternativepathways(chymase,
cathepsin G,chymostatin
ATII generation)
Bradykinin
Inactiveproducts
ACE
? angioedema
cough
increase nitric oxide,prostacyclin
(improved endothelial function ?anti-atherosclerotic?)
hypotension
Hypothesized Atherosclerotic Effects Hypothesized Atherosclerotic Effects of Angiotensin IIof Angiotensin II
Causes SMC growth and migrationCauses SMC growth and migration Activates macrophagesActivates macrophages Increases platelet aggregationIncreases platelet aggregation Stimulation of PAI1Stimulation of PAI1 Made directly by SMCs & macrophagesMade directly by SMCs & macrophages A-II stimulation causes endothelial dysfunctionA-II stimulation causes endothelial dysfunction
Gibbons, G.H. et al, NEJM, 330(20):1431-1438.
AngiotensinogenAngiotensinogen
Angiotensin IAngiotensin I
Angiotensin IIAngiotensin II
Angiotensin II ReceptorsAngiotensin II Receptors
Angiotensin II FormationAngiotensin II FormationAlternate Pathways*Alternate Pathways*
• CAGECAGE• Cathepsin GCathepsin G• ChymaseChymase
ReninReninReninRenin
• t-PAt-PA• Cathepsin GCathepsin G• ToninTonin
ACEACEACEACE
Dzau, V.J. et al, J of Hypertension, 11(suppl 3):1993.
* The clinical significance ofthe alternate pathway is
unknown
AT Receptors
AT1 AT2
FetusVasculature
HeartVasculatureBrainAdrenal
Proposed Pathophysiologic Effects Proposed Pathophysiologic Effects of Angiotensin IIof Angiotensin II
Hypertension, 23(2):258, 1994.
Angiotensin IIAngiotensin II
ATAT11
ReceptorReceptorVasoconstrictionVasoconstrictionAldosteroneAldosteroneProductionProduction
Cell GrowthCell Growth
LVHLVHVascularVascular
RemodelingRemodeling
TVRTVR
BPBP
Sodium/WaterSodium/WaterRetentionRetention
BPBP
AT Receptors
AT1 AT2
anti-proliferationHypertrophyProliferationThirstAldosteroneProliferation
AT ReceptorsAT Receptors
AT1 AT2
decreaseddecreasedProliferationProliferation
ATII
losartanlosartan
1000x
ARB’s
Angiotensin Receptor Blockers
Angiotensin II ReceptorBlocking Agents
Generic Trade Date Publications(1995-1999)
losartan Cozaar 12/95 1,296valsartan Diovan 12/96 117irbesartan Avapro 9/97 96
candesartan Atacand 6/98 154eprosartan Teveten 1/5/98 48tasosartan Verdia 1/28/98 6telmisartan Micardis 11/12/98 23
1/6/2000
Angiotensin II ReceptorBlocking Agents
Generic Trade Peak ½ Life DoseSchedule
Dose
losartan Cozaar 1-4 hrs 2-10 hrs qd or q12h 25-100 mg
valsartan Diovan 2-4 hrs 6 hrs qd 80-320 mg
irbesartan Avapro 1.5-2 hrs 11-15 hrs qd 150-300 mg
candesartan Atacand 3-4 hrs 9 hrs qd or q12h 8-32 mg
eprosartan Teveten 1-2 hrs variable Q12h 400-600 mg
tasosartan Verdia 1-2 hrs 10 hrs Q24h 100 mg
telmisartan Micardis 0.5-1 24 Q24h 40-160 mg
ELITE
Bertram, Lancet 1997;349:747
• Evaluation of Losartan In The Elderly• Losartan vs captopril• Primary endpoint
Increase of creat >0.3 mg%• Secondary endpoints
All cause mortalityHospital admit for CHFDeath + admit for CHF
ELITE
Bertram, Lancet 1997;349:747
• Age > 65 years• CHF NYHA class II-IV• EF < 40%• No prior ACE therapy• Double-blind, randomized, placebo• losartan-352 pts, captopril-370 pts• 48 weeks of follow-up
ELITE
Bertram, Lancet 1997;349:747
Persistent Increased Creatinine
10.5 10.5
0102030405060708090
100
Losartan Captopril
Pe
rce
nt
ELITE
Bertram, Lancet 1997;349:747
Single Rises in Creatinine
26.1 29.7
0102030405060708090
100
Losartan Captopril
Pe
rce
nt
P=0.42
ELITE
Bertram, Lancet 1997;349:747
Death and/or CHF Admissions
9.4 13.2
0102030405060708090
100
Losartan Captopril
Pe
rce
nt
P=0.075
ELITE
Bertram, Lancet 1997;349:747
All Cause Mortality *
4.8 8.7
0102030405060708090
100
Losartan Captopril
Pe
rce
nt
P=0.035
*primarily SCD
ELITE
Bertram, Lancet 1997;349:747
NYHA Class I or II
66 64
80 81
0102030405060708090
100
Losartan Captopril
Pe
rce
nt
P=0.035
ELITE
Bertram, Lancet 1997;349:747
DC'ed Rx or Died
18.530
0102030405060708090
100
Losartan Captopril
Pe
rce
nt
P<0.001
ELITE II
Unpublished
• Evaluation of Losartan In The Elderly II• Losartan vs captopril• Primary endpoint
All cause mortality
ELITE II
Unpublished
• Age 62.7 + 11 years• 80% male• NYHA Class II / III / IV -- 61.7 / 36.2 / 1.9%• LVEF 26.7 + 7.1%• Double-blind, randomized, placebo• Total 3,152 patients• Follow-up until 510 deaths
ELITE II
Unpublished
All Cause Mortality
15.9 14.9
0102030405060708090
100
Losartan Captopril
Perc
en
t p = 0.16
ELITE II
Unpublished
Sudden Cardiac Death
9 7.3
0102030405060708090
100
Losartan Captopril
Perc
en
t p = 0.08
AT1 Inhibitors
“Indeed the incidence of all side effects of AT1 receptor antagonist appears to be much the same as placebo, which cannot be said for any other class of antihypertensive drug.”
Struthers, Heart 1998;80:5
AT Effects on Coagulation
Chabielska, J Physiol Pharm 1998;49:251
7 day Rxcaptopril
7 day Rxlosartan
control
Rats
Abdominal Aortic Loop Thrombosis
Thrombosis 46% lessThrombosis
42% lessThrombosis
Tedesco, J Hum Hypertens 1998;12:505
Reduction in LV Mass
-11
-5
-20
-15
-10
-5
0
Losartan HCTZ
LV
ma
ss
re
du
c -
g/m2 P=0.38
Special Considerations
• Losartan is a uricosuric
ARB’s
• Very similar to ACE inhibitors• VERY well tolerated, ?placebo rate of side effects• Advantageous in ACE cough• Advantageous in ACE angioedema• May have other, advantageous effects
(thrombosis, proliferation, renal)• Consider as primary therapy in selected subsets
Summary• Please, find more hypertensive patients
• Please, treat more hypertensive patients
• Please, achieve goal in more hypertensive patients
• Consider the underlying pathology
• Consider a broad range of old and new drugs