drugs used in congestive heart failure 医学院药理学研究所 ...

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DRUGS USED IN CONGESTIVE HEART FAILURE 医学院药理学研究所 丁 华. CHAPTER 27. Congestive heart failure (CHF) : the definition of CHF Essence: Cardiomyopathy of overload. - PowerPoint PPT Presentation

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DRUGS USED IN CONGESTIVE HEART FAILURE

医学院药理学研究所 丁 华

CHAPTER 27

Congestive heart failure (CHF) :

the definition of CHF

Essence: Cardiomyopathy

of overload

Section 1

Pathophysiology of Heart Failure and The Treatment Drugs

A. Change of cardiac function and

configuration

B. Change of neuroendocrine system

NA 、 RAAS 、 AVP 、 ET 、 TNFα↑ ANP 、 NO 、 PGI2↓

C. Change of signal transmit of β-R

Pathophysiology of Heart Failure

心功障碍 (收缩功能↓①,舒张功能↓⑧ )

输出量↓

血管收缩 神经激素↑ 心肌 β1R↓⑦ ( RAS↑④ 、 CA↑ )

阻抗↑ 水钠潴留 ⑤ 心缩力↓ 后负荷↑② 顺应性↓ 血容量↑

血管肥厚、重构⑥ 心肌肥大、重构⑥ 静脉淤血 前负荷↑③

心功障碍的病理生理学与药物作用的环节

CHF 治疗的演变

20 世纪 20 年代洋地黄开始应用(一)纠正血流动力学异常( 20 世纪 50 ~ 80 年代) 1948 ~ 1968 强心苷、利尿药 1969 ~ 1978 血管扩张药 1978 ~ 1988 新型正性肌力药

(二)修复衰竭心肌的生物学性质 ( 90 年代~ 2001 年)

90 年代以来 ACEI 、 β 受体阻断药

( 三)逆转心肌异常( 2001 年起) 1 .扩大、强化对心衰时激活的神经 激素 - 细胞因子的抑制 : ET 、 AVP 、 TNFα 2 .基因治疗

药物治疗 CHF 的目的

1 .改善血流动力学状况并尽快缓解   症状。 2 .防止心肌继续损害并延缓自然病   程。 3 .降低病死率,延长存活期。

Rationale for pharmacologic intervention in CHF

The goals in treating heart failure are to improve the patient's quality of life and to prolong it.

Improving hemodynamics with inotropic drugs does not decrease mortality; long-term treatment directed towards neurohormonal factors with ACE inhibitors and beta-blockers can decrease mortality

Section 2 Cardiac Glycosides

Digoxin (地高辛)Digitoxin (洋地黄毒苷)Cedilanide (毛花苷丙 , 西地兰)Strophanthin K (毒毛花苷 k)

Digitalis

A. Effect on cardiac1. Positive inotropic action (1) ↑ both the force and the velocity of myocardial contraction, prolong diastolic. (2) ↑ the cardiac output. (3) ↓ myocardial oxygen consumption

Pharmacological actions:

Mechanism:

Cardiac glycosides

↓Na+ - K+ATPase

[Na+] i↑

Na+/Ca2+ exchange

[Ca2+] i ↑

myocardial contraction ↑

2. Negative chronotropic action

a. ↑vagal stimulation b. Resume sensitivity of carotid sinus baroreceptor.c.↑sensitivity of cardiac muscle to Ach.

3. Electrophysiological effect

↓AV conduction

shorten ERP of atria

↑ P-f automaticity , shorten ERP

强心苷对心肌电生理的作用

电生理特性 窦房结 心房 房室结 浦肯野纤维

自律性 降低 增高

传导性 减慢

有效不应期 缩短 缩短

B.Effect on nerve-incretion:

1. ↓ sympathetic activity

2. ↑ pneumogastric (vagal) activity

3. ↓ renin secretion, ↓RAS

4. ↑ ANP secretion

C. Diuresis effect

1.↑CO renal blood flow↑

2.↓Na+-K+-ATPase ↓Na+

reabasorption in the tubules

↓ H2O and Na+ retention.

drugs absorp% t1/2 H-E cir % last

digitoxin 90~100 5d 27 2~3 w digoxin 60~ 85 36h 7 5~7dstroph K 2~5 19h 0 1~3d

Pharmacokinetics

1. CHF Digoxin: 0.125 ~ 0.25mg/d , 6 ~ 7d get to Css 2. Certain types of arrhythmia (1) Atrial fibrillation , atrial flutter (2) Paroxysmal supraventracular tachycardia

Clinical uses

临床评价:

1997 年 DIG 试验 (Digitalis Investigation Group trial ) 6800 例 , 应用地高辛 0.25mg/d ,治疗 28 ~ 58 个月。随访 3.5 年。 地高辛能改善症状,降低再入院率,减少 CHF恶化所致的病死率与住院率,但对总病 死率 (34.8% : 35.1%)无影响。

Toxicity, Prevention and

Management

toxicity

1. Gastrointestinal reactions Nausea and vomiting2. CNS disturbance

Changes in color vision 3. Cardiac toxicity ventricular premature contraction ventricular tachycardia ventricular fibrillation sinus bradycardia atria-ventricular block

Treatment of digitalis toxicity

1) Stop using cardiac glycosides and K+-depleting diuretics.

2) Antiarrhythmic KCL is administered orally or by slow, careful intrave

nous infusion if hypokalemia is present; Phenytoin can be given for ventricular and atrial arrh

ythmia. Lidocaine can be used to treat ventricular tachyarrhy

mias. Atropine can be used to treat A-V block. 3) Digoxin antibodies

Section 3 ACEI and AT1-R Antagonist

ACEI (angiotensin-converting enzyme inhibitor) :

Captopril (卡托普利 ) Enalapril (依那普利 ) Ramipril (雷米普利)

Pharmacological action

1.Influence nerve-incretion: (1) Ang II ↓

(2) Inhibit bradykinin degradation →

↑bradykinin levels →NO,EDHF,

PGI2↑ (3) ↓ ALD secretion

2. Improve hemodynamics

a. Dilate blood vessels , ↓ peripheral resistance; b. Dilate coronary, improve cardiac function c.↑renal blood flow

3. Inhibit remodeling of cardiac

muscle and vessel

↓Ang and ALD formation , Inhibite Ⅱ proliferation and hypertrophy

of myocardial cells and VSMC,

improve cardiovascular function.

Clinical Uses

1.CHF 2.Hypertension

39项 8308 例随机时照临床试验评价 :ACEI使 CHF总死亡率降低 24%,显著改善心梗后 CHF患者预后,缓解临床症状,提高运动耐力,改善生活质量,防止和逆转心肌肥厚。

ACEI可作为各型 CHF 的首选药,常与利尿药,地高辛合用。

临床评价 :

ACE inhibitors are now ACE inhibitors are now considered to be a considered to be a cornerstone cornerstone in the management of most forms in the management of most forms

of of heart failureheart failure and many forms and many forms of of cardiac hypertrophycardiac hypertrophy

Braunwald &BriBraunwald &Bristowstow

Circulation 2000Circulation 2000

Untoward Reaction

hypotension, dry cough , angioedema, hyperkalemia

Contraindication: Pregnant woman

Renal artery stenosis

Angiotensin II receptor antagonist

Losartan (氯沙坦) Valsartan (缬沙坦)

Irbesartan (伊白沙坦)

Characteristics:

Arrest Ang II combine with AT1R

(1) More selective blockers of

Ang II than ACEI

(2) No effect on bradykinin metabolism

ACEI 与 ARB特点比较

ARB 完全阻滞 ACE和非 ACE途径生成的 AngII 与受体结合

只阻滞 AT1 受体效应 不影响 AT2 、 AT3 、 AT4

受体 不影响缓激肽系统 不发生咳嗽 无 AngII 、 Ald逃逸

ACEI 只阻滞 ACE途径生成的 An

gII 抑制 AT1 、 AT2 、 AT3 、

AT4 受体效应 加强缓激肽系统作用 咳嗽相对常见 有 AngII 、 Ald逃逸

Section 4 β-receptor blockers (adrenergic antagonists):

1. The mechanism of action in treatment of CHF (1) Anti-sympathetic activity a. Up-regulate β1-R in failing heart, can restore catecholamine re

sponsiveness. b. inhibit RAAS →↓cardiac load c.↓myocardial damage from CA, reduce HR and myocardial oxy

gen consumption (2) Anti-arrhythmia and anti-myocardial ischem

ia (3)Antioxidation — carvedilol

适应症:

所有 NYHA 心功能Ⅱ、Ⅲ级病情稳定,LVEF<40%者,应尽早使用,平均奏效期 3 个月。 20多个随机对照试验 ,>10000 例 NYHA心功能Ⅱ、Ⅲ级患者,长期应用 β 阻断剂治疗,死亡率降低 34%。

美托洛尔美托洛尔提高扩张型心肌病的左心室射血分数提高扩张型心肌病的左心室射血分数

* P<0.05*** P<0.0001# P=0.013 ,与标准治疗比较

40

35

30

25

20

左心室射血分数

(% )

标准治疗美托洛尔

基线 第一天 第一月 第三月

***

*

#

Application attention: 1. 选择合适的制剂 Selective β1-R blocker :

Metoprolol 、 Bisoprolol (美多洛尔) (比索洛尔 )

Nonselective β and α1-R blocker: Carvedilol (卡维地洛)

2 、应用恰当的剂量

起始量必须极小。Metoprolol 12.5mg/d

Bisoprolol 1.25mg/d

Carvedilol 3.125mg/d

每 2 ~ 4周剂量加倍,达最大耐受量或目标剂量后长期维持。

3 、合用利尿药、 ACEI 、地高辛。

4 、密切观察可能出现的不良反应: 血流动力学恶化,心动过缓,低血

压。5 、禁忌症: 支气管哮喘、心动过缓(心率 < 60 次 /分)、Ⅱ度以上房室传导阻滞、 低血压。

Section 5 Diuretics Mechanism: decreased salt & water retention (blood volume) lea

ds to decreased ventricular preload Clinical Effect: decreased symptoms of heart failure (ie. edema) decreased cardiac size leads to improved cardiac fun

ction Administration: start with a thazide diuretic and switch to a more pow

erful agent as required (furosemide) check serum electrolytes to prevent K+ loss

Aldosterone antagonists Spironolacton(螺内酯 )

Actions: Competitive inhibition of the aldosterone receptor.

↓ H2O and Na+retention ,

↓hypertrophy of myocardial cells and myocardial remodeling

↓arrhythmias and sudden death.

Section 6 Vasodilators

Nitrate esters(硝酸酯类 )

Hydralazine (肼屈嗪) Sodium nitroprusside (硝普钠 ) Praz

osin (哌唑嗪 )

Mechanism of Action 1. Dilate vein ↓preload ↓ lung congestive 2. Dilate artery ↓ afterload ↑cardiac output

Defects : Sympathetic and RAAS

activity ↑, H2O and Na+ retention .

常用扩血管药及特点

药物 作用部位

动脉 静脉

硝酸酯类 + +++ 肼屈嗪 +++ - 硝普钠 +++ +++ 哌唑嗪 ++ ++

β-Adrenoceptor Agonist Dobutamine(多巴酚丁胺) Ibopamine( 异波帕胺) Phosphodiesterase Inhibitors Amrinone (氨力农) Milrinone (米力农) Vesnarinone ( 维司力农)

Section 7 Others

β-sti PDEI (+) (-) AC PDE

ATP cAMP↑ 5’-AMP

Mechanism of action:

Machanism of Action of PDEI

1. Inhibit PDE-III ↑cAMP ↑PKA

Ca2+in cardiac contractility ↑

2. Dilate blood vessel ,↓cardiac load

clinical uses Serious CHF

3~5d, IV

Calcium sensitizers ↑ sensitive of troponin C ( TnC )

to Ca2+ ,↑ cardiac contractility Pimobendan (匹莫苯) Sulmazole (硫马唑 ) Levosimendan (左西孟坦)↑ sensitive to Ca2+ ,↓ PDEⅢ

Long-acting: amlodipine(氨氯地平 )

Mechanism :1. Dilate artery vessel ,↓cardiac load 2. Dilate coronary artery, improve myocardial ischemia3.↓Ca2+ influx, improve cardiac

diastole function

Uses: Diastolic heart failure

Calcium Antagonist

心衰的常规治疗过去 : 强心、利尿、扩血管现在 : 以神经内分泌拮抗剂为主的三大类或四大类药物的联合应用 ,即利尿剂、 ACEI 、 β 受体阻断剂的联合应用,必要时再加地高辛。

病 例 赵 X ,62 岁。患者 2 年前开始常感劳动后心悸、气短。近半年来,病人病情加重,经常心慌、气促、咳嗽、胃纳差,下肢浮肿,有时痰中带血,曾在当地医院用青霉素、双氢克尿噻、速尿、地高辛治疗,症状有所缓解。近日来,症状较前明显加重,稍动即喘、呼吸困难、不能平卧、少尿。颈静脉怒张,肝于肋下 4cm ,双下肢呈凹陷性水肿( ++ ),心率每分钟 96 次,心尖部可闻及 II 级收缩期杂音和中度舒张期杂音,口唇轻度紫绀。

入院诊断为:充血性心力衰竭。心功能Ⅳ级, 讨论:对该病人应选用哪些药物治疗?简述用药依据。

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