Zhao Mingyao Bmc.zzu. 2004-3-8

Zhao Mingyao BMC.ZZU. 2004-3-8

The 10 Leading Causes of Death: United States, 2000 Diseases of the Heart

711

Cancers

553

Stroke

167

COPD

122

Unintentional Injuries

98

Diabetes Mellitus Influenza &Pneumonia

69

Alzheimer's Disease

65

Nephritis &Nephrosis

50

Septicemia 0

37

100

200

300

400

500

600

700

800

31

Number of Deaths (in Thousands)

CDC. National Vital Statistics Report 2002; Vol 50, No. 15

1.What is the concept of heart failure? heart pump failure myocardial failure chronic congestive heart failure

• Heart pump function

SV

CO HR

myocardial contractility myocardial relaxility preload (VR) afterload (ejection impedance) Prolonged overload metabolism structure change

2.Why is there heart failure with highoutput ?

3.Why doesn`t patient show obvious sign and symptom in the early stage of heart failure? heart rate frank-starling law myocardial hypertrophy blood volume and redistribution of blood flow

• 4.What is compensatory meaning of HR increased in heart failure? CO = SV X HR

Frank-Starling law Contractile power Contractility

Frank-Starling Curve Total Blood Volume Atrial Contribution

Body Position

Intra-Thoracic Pressure

Stretch of Myocardium Venous Tone

Ventricular Performance

Pumping Action of Skeletal Muscle

End-Diastolic Volume

Pericardial Pressure, Compliance

5.How many types of ventricle hypertrophy are there in heart failure? concentric eccentric sarcomeres in parallel or in series

concentric

eccentric

6.Why are there two side effects of heart hypertrophy (myocardial remodeling )? fibril, mit, vol ↑ but phenotype change, collagen(~ I, thick ,stiff; ~III ) Myosin heavy chain MHC α- MHC ↓,β- MHC↑

myocyte hypertrophy and widening of interstitial spaces due to depostion of collagen, inflammatory cells and amyloid.

7.What are pathogenesis of heart failure myocardial contractility↓ decreased diastolic properties ↓ asymmetry and asynchronism in ventricular contraction and relaxation

8.How does myocardial contractility decrease ? myocardial injury myocardial energy : production & consumption

dysfunction of excitation-contraction coupling ( Ca2+ delivery disorder )

9.Why does insufficiency of vitamin B1 lead to heart failure? Pyruvic acid

~ decarboxylase

ATP

acetyl Co A Krebs citric acid cycle

10.How does diastolic properties of myocardium decrease ? : loosing, cytosol Ca2+ , Ca2+ pump compliance diastolic load

Diastolic process = Relaxility

compliance diastolic load

11.What are the effects of heart failure to body ?

myocardial contractility↓ diastolic properties↓

CO ↓

?

heart pump↓

VR↓pulmonary congestion

?

systemic congestion

?

12.What are the changes of cardiac function during heart failure? CO, CI, EF, LVEDP(V), PCWP,CVP dp/dtmax, -dp/dtmax, Vmax ( T= π rP/h)

13.Why does left heart failure lead to dyspnea?

14.How does orthopnea occur during heart failure?

Orthopnea means shortness of breath while lying down.

Orthopnea means shortness of breath while lying down.

15.What is mechanism of paroxysmal nocturnal dyspnea ?

16.How to treat heart failure? removal cause prevent predisposing factor improving cardiac function: inotropic agent digitalis Ca 2+ channel antagonist or Ca 2+ receptor blocker vasodilator agents

• Brief history about treating heart failure: 1940 times heart + kidney mode 1970 times heart + circulation mode 1990 times heart + endocrine mode ACEI, β-receptor blocker ,α- receptor blocker

Belt long, life short, why?