Gilead -Topics in Human Pathophysiology

Fall 2010 Drug Safety and Public Health

Figure 8.7bFigure 8.7b

Systole – ventricles contract, semilunar valves open to allow blood to large arteries; AV valves close to prevent backflow to the atria

Diastole – ventricles relax, semilunar valves close to prevent backflow into the ventricles, AV valves open to allow ventricles to fill

SA node is primary pacemaker AV node is secondary pacemaker AV bundle carries signal to ventricles Electrical signal stimulates muscle

contraction For the conduction system to work properly

adequate blood supply is required.

Coronary artery disease Myocardial ischemia Myocardial hypoxia Myocardial infarct Myocardial necrosis

From wikipedia

Age

Male sex

Heredity

Smoking

Diabetes mellitus

Hypertension

High cholesterol

Obesity

Lack of exercise

Diagnosis◦ BP monitoring◦ Symptoms◦ ECG◦ Angiogram◦ Stress Test◦ Nuclear myocardial

perfusion tests

For myocardial perfusion imaging (MPI) A2A adenosine receptor agonist Vasodilates coronary arteries as if exercising Injected into blood stream prior to gamma

camera scan Can give a good indication of myocardial

perfusion

• Treatment– Coronary bypass

surgery– Angioplasty– Stents– Cholesterol lowering

agents– Anticoagulents– Antianginal

medications

For angina Thought to inhibit a sodium ion

channel in the cardiac muscle cells Contraction of those cells might

normally cause compression of cardiac blood vessels during diastole.

Can be taken with other anti-anginal meds

Very effective

Congestive Heart Failure

• Heart becomes weak• Blood backs up in veins and capillaries• Fluid excess in tissues• Symptoms include shortness of breath,

edema, difficulty breathing (especially when lying down,) difficulty exercising

Congestive Heart Failure

• Causes: – cardiomyopathy– hypertension– lung disease– coronary artery disease– previous MI– valve disease

Blood Vessels and Pressure

• Artery structure and function• Control over smooth muscle• Vascular Disease

– Atherosclerosis– Pulmonary hypertension

Figure 8.10

Figure 8.1

Vessel Wall Structure

• Tunica intima – epithelium and connective tissue

• Tunica media – smooth muscle• Tunica externa– connective tissue and

epithelium

Arterial blood pressure and flow

• Systolic and diastolic pressure• Regulatory factors

– Cardiac – Sympathetic nervous system from vasomotor

center of brain stimulates smooth muscle– Chemical messengers – hormones, paracrines

Components of Orthe Nervous System

Figure 11.1

Organization of the Nervous System

Figure 11.12 (1 of 2)

Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

Figure 11.12 (2 of 2)

Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

Table 19.2

Hormonal Control of Blood Pressure

Pulmonary Arterial Hypertension (PAH)

• Pulmonary arteries become narrowed causing decreased gas exchange and difficulty breathing

• Causes R ventricular hypertrophy

• Blood will back up in veins

Pulmonary Hypertension

Common causes of PAH

Symptoms of PAH

• Chest pain, usually in the front of the chest• Dizziness• Fainting• Fatigue• Leg edema• Light-headedness during exercise• Shortness of breath during activity• Weakness

Treatment for PAH• Letairis (ambrisentan)• Flolan or other prostacyclins• Bosentan (Tracleer)• Calcium channel blockers• Diuretics• Sildenafil (Viagra)• Supplemental oxygen• Surgical correction of defects• Lung transplant