Most IMP Quesation Pharmacology of Drugs Acting on CVS / Pharmacology of Drugs Acting on CVS / CARDIOVASCULAR SYSTEM PDF / CVS System

 

CARDIOVASCULAR SYSTEM 

 Introduction Cardiovascular system comprises of the heart and an extensively branched structure of blood vessels that transports oxygen, nutrients , heat, and other substances throughout the body. Cardiac or heart muscles are involuntary striated muscles found in the heart and its walls, especially in the myocardium (the muscle tissue forming a thick middle layer amid the outer epicardium and the inner endocardium ). For delivering oxygen and nutr ients, and removing waste products such as carbon dioxide, the cardiac muscle cells depend on the available blood and e lectrical supply. The myocardial tissue is made up of contracting cells and conducting cells . The pumping action of the heart involves the contracting cells. The conducting tissues of the heart include SA node (acts as the pacemaker), AV node, and His -Purkinje system. Various parts of the conducting tissue exhibit automaticity. Cardiac muscles being specialised tissues have distinct properties of:

 1) Excitability: It is the ability of cardiac cells to depolarise in response to a stimulus. 

2) Contractility: It is the ability of myocardium to contract and pump blood out of the heart. 

3) Automaticity: It is the ability of cardiac cells to generate electrical impulses spontaneously.   

1.1.2. Hemodynamics 

The study of the dynamic behaviour of blood is termed hemodynamics. Pressures are generated in the various parts of heart (cardiovascular pressures) when blood flows from one chamber to another, when valves open and close, and when the myocardium contracts and relaxes. Catheters are used to measure and monitor these pressures by placing their tips in the atria, pulmonary artery , or systemic arteries; these are called the hemodynamic lines.

SUMMARY

The details given in the chapter can be summarised as follows

 1) Cardiovascular system comprises of the heart and an extensive ly branched structure of blood vessels that transports oxygen, nutrients, heat, and other substances throughout the body.

 2) The myocardial tissueis made up of contracting cellsand conducting cells.

3) The study of the dynamic behaviour of blood is termed hemodynamics. 

4) There are five phases of the action potential of cardiac cells. 

5) When a heart fails to pump blood in a quantity sufficient to fulfil the body requirements, a condition of Congestive Heart Failure (CHF) occurs, which is also known as a Heart Failure (HF). 

6) Cardiac glycosides are derived from plant derivatives and are steroidal in nature. 

7) Digoxin, digitoxin, and ouabain are the commonly used cardiac glycosides. 

8) Route of administration of digitalis is either oral or intravenous. 

9) When administered in co mparatively small therapeutic doses, digitalis improves the ability of excitation of the myocardium and the conduction velocity. 

10) Digitalis improves circulation and decreases sympathetic activity, thereby increasing the blood flow to kidneys. 

11) Digitalis is highly toxic . It has a low margin of safety with a therapeutic index ranging from 1.5-3.

 12) Bipyridine derivatives (e.g., amrinone and milrinone) show phosphodiesterase (PDE) inhibiting activity.

 13) Bipyridines increase the production of cAMP in the heart and blo od vessels, and thus exert a positive inotropic action along with vasodilator activities. 

14) The β-adrenergic agonists increase the cardiac output, and decrease the ventricular filling pressure and pre-load. 15) The β-adrenergic agonists may cause tachyphylaxis. 

16) Diuretics increase the excretion of salt and water. 

17) The production of angiotensin II from angiotensin I is inhibited by ACE inhibitors.

 18) A condition in which the blood pressure of systemic artery increases beyond the normal pressure is known as hypertension. 

19) Drugs promoting urine output are known as diuretics.

 20) Losartan is a competitive antagonist of angiotensin II. 

21) Trimethaphan is the only ganglionic blocker used nowadays. 

22) Reserpine is an alkaloid obtained from the roots of the plant Rauwolfia serpentina.

 23) Propranolol is used in mild to moderate hypertension.

 24) Calcium channel blockersare commonly used in the treatment of hypertension. 

25) Vasodilators cause vasodilation by directly relaxing the vascular smooth muscles.

 26) Angina pectoris (or chest pain) is a symptom experienced due to myocardial ischemia, wherein the blood supply to the heart decreases. 

27) Organic nitrates and nitrates are used in angina pectoris. 

28) Ranolazine reduces the number of angina episodes per week and increases exercise tolerance. 

29) Arrhythmia is a common disorder of cardiac excitation, which may be benign but may also be fatal ( e.g., ventricular fibrillation following a heart attack). 

30) Sodium channel blockers are the most widely used antiarrhythmic agents.

 31) Antihyperlipidemics are the group of drugs p rescribed in adjuvant therapy to reduce elevated cholesterol levels in patients with high cholesterol and LDL levels in the blood.

 32) Statins are the most effective and best tolerated agents used to treat hyperlipidemia.

33) Cholestyramineis a bile acid sequestrant which serves as ion exchange resins. 

34) Fibrates are the drugs reducing the triglyceride levels more than LDL cholesterol levels.

 35) Fibrates act as agonists for the nuclear transcription factor Peroxisome Proliferators-Activated Receptor -alpha (PPAR-alpha), at the molecular level. 

36) Triglyceride synthesis and lipolysis inhibitors act either by inhibiting the synthesis of triglyceride or by inhibiting the process of lipolysis. 

 

Very Short Answer Type Questions 

1) What is hemodynamics? 

2) What are the uses of hemodynamic lines? 

3) Define cardiac glycosides. 

4) Give therapeutic uses of cardiac glycosides. 

5) Define bipyridines. 

6) What are -adrenergic agonists? 

7) Define diuretics.

 8) What are vasodilators? 

9) Define ganglion blockers. 

10) What is angina pectoris?

 11) What is arrhythmia? 

12) Explain fibrates.

 Short Answer Type Questions 

1) Explain the electrophysiology of heart.

 2) Classify the drugs employed in treatment of CHF.

 3) Give mechanism of cardiac glycosides. 

4) Give mechanism of action, uses and adverse effect of β-adrenergic Agonists

 5) Classify anti-hypertensive drugs.

 6) Explain the mechanism of action of diuretics. 

7) Write about captopril and enalapril.

 8) Classify and give mechanism of action of calcium channel blocker.

 9) What are organic nitrites and nitrates and give its mechanism of action. 

10) Classify anti-arrhythmic drugs.

 1.8.5. Long Answer Type Questions

 1) Explain cardiovascular system and its drugs in detail. 

2) Classify and explain drugs of anti-hypertensive drugs in detail. 

3) Explain adrenergic drugs in detail. 

4) Write about anti-arrhythmic drugs in detail.

5) Write about potassium channel blockers. 

6) Discuss in detail about anti-hyperlipidimic drugs.

 Introduction Cardiovascular system comprises of the heart and an extensively branched structure of blood vessels that transports oxygen, nutrients , heat, and other substances throughout the body. Cardiac or heart muscles are involuntary striated muscles found in the heart and its walls, especially in the myocardium (the muscle tissue forming a thick middle layer amid the outer epicardium and the inner endocardium ). For delivering oxygen and nutr ients, and removing waste products such as carbon dioxide, the cardiac muscle cells depend on the available blood and e lectrical supply. The myocardial tissue is made up of contracting cells and conducting cells . The pumping action of the heart involves the contracting cells. The conducting tissues of the heart include SA node (acts as the pacemaker), AV node, and His -Purkinje system. Various parts of the conducting tissue exhibit automaticity. Cardiac muscles being specialised tissues have distinct properties of:

 1) Excitability: It is the ability of cardiac cells to depolarise in response to a stimulus. 

2) Contractility: It is the ability of myocardium to contract and pump blood out of the heart. 

3) Automaticity: It is the ability of cardiac cells to generate electrical impulses spontaneously.   

1.1.2. Hemodynamics 

The study of the dynamic behaviour of blood is termed hemodynamics. Pressures are generated in the various parts of heart (cardiovascular pressures) when blood flows from one chamber to another, when valves open and close, and when the myocardium contracts and relaxes. Catheters are used to measure and monitor these pressures by placing their tips in the atria, pulmonary artery , or systemic arteries; these are called the hemodynamic lines.

SUMMARY

The details given in the chapter can be summarised as follows

 1) Cardiovascular system comprises of the heart and an extensive ly branched structure of blood vessels that transports oxygen, nutrients, heat, and other substances throughout the body.

 2) The myocardial tissueis made up of contracting cellsand conducting cells.

3) The study of the dynamic behaviour of blood is termed hemodynamics. 

4) There are five phases of the action potential of cardiac cells. 

5) When a heart fails to pump blood in a quantity sufficient to fulfil the body requirements, a condition of Congestive Heart Failure (CHF) occurs, which is also known as a Heart Failure (HF). 

6) Cardiac glycosides are derived from plant derivatives and are steroidal in nature. 

7) Digoxin, digitoxin, and ouabain are the commonly used cardiac glycosides. 

8) Route of administration of digitalis is either oral or intravenous. 

9) When administered in co mparatively small therapeutic doses, digitalis improves the ability of excitation of the myocardium and the conduction velocity. 

10) Digitalis improves circulation and decreases sympathetic activity, thereby increasing the blood flow to kidneys. 

11) Digitalis is highly toxic . It has a low margin of safety with a therapeutic index ranging from 1.5-3.

 12) Bipyridine derivatives (e.g., amrinone and milrinone) show phosphodiesterase (PDE) inhibiting activity.

 13) Bipyridines increase the production of cAMP in the heart and blo od vessels, and thus exert a positive inotropic action along with vasodilator activities. 

14) The β-adrenergic agonists increase the cardiac output, and decrease the ventricular filling pressure and pre-load. 15) The β-adrenergic agonists may cause tachyphylaxis. 

16) Diuretics increase the excretion of salt and water. 

17) The production of angiotensin II from angiotensin I is inhibited by ACE inhibitors.

 18) A condition in which the blood pressure of systemic artery increases beyond the normal pressure is known as hypertension. 

19) Drugs promoting urine output are known as diuretics.

 20) Losartan is a competitive antagonist of angiotensin II. 

21) Trimethaphan is the only ganglionic blocker used nowadays. 

22) Reserpine is an alkaloid obtained from the roots of the plant Rauwolfia serpentina.

 23) Propranolol is used in mild to moderate hypertension.

 24) Calcium channel blockersare commonly used in the treatment of hypertension. 

25) Vasodilators cause vasodilation by directly relaxing the vascular smooth muscles.

 26) Angina pectoris (or chest pain) is a symptom experienced due to myocardial ischemia, wherein the blood supply to the heart decreases. 

27) Organic nitrates and nitrates are used in angina pectoris. 

28) Ranolazine reduces the number of angina episodes per week and increases exercise tolerance. 

29) Arrhythmia is a common disorder of cardiac excitation, which may be benign but may also be fatal ( e.g., ventricular fibrillation following a heart attack). 

30) Sodium channel blockers are the most widely used antiarrhythmic agents.

 31) Antihyperlipidemics are the group of drugs p rescribed in adjuvant therapy to reduce elevated cholesterol levels in patients with high cholesterol and LDL levels in the blood.

 32) Statins are the most effective and best tolerated agents used to treat hyperlipidemia.

33) Cholestyramineis a bile acid sequestrant which serves as ion exchange resins. 

34) Fibrates are the drugs reducing the triglyceride levels more than LDL cholesterol levels.

 35) Fibrates act as agonists for the nuclear transcription factor Peroxisome Proliferators-Activated Receptor -alpha (PPAR-alpha), at the molecular level. 

36) Triglyceride synthesis and lipolysis inhibitors act either by inhibiting the synthesis of triglyceride or by inhibiting the process of lipolysis. 

 

Very Short Answer Type Questions 

1) What is hemodynamics? 

2) What are the uses of hemodynamic lines? 

3) Define cardiac glycosides. 

4) Give therapeutic uses of cardiac glycosides. 

5) Define bipyridines. 

6) What are -adrenergic agonists? 

7) Define diuretics.

 8) What are vasodilators? 

9) Define ganglion blockers. 

10) What is angina pectoris?

 11) What is arrhythmia? 

12) Explain fibrates.

 Short Answer Type Questions 

1) Explain the electrophysiology of heart.

 2) Classify the drugs employed in treatment of CHF.

 3) Give mechanism of cardiac glycosides. 

4) Give mechanism of action, uses and adverse effect of β-adrenergic Agonists

 5) Classify anti-hypertensive drugs.

 6) Explain the mechanism of action of diuretics. 

7) Write about captopril and enalapril.

 8) Classify and give mechanism of action of calcium channel blocker.

 9) What are organic nitrites and nitrates and give its mechanism of action. 

10) Classify anti-arrhythmic drugs.

 1.8.5. Long Answer Type Questions

 1) Explain cardiovascular system and its drugs in detail. 

2) Classify and explain drugs of anti-hypertensive drugs in detail. 

3) Explain adrenergic drugs in detail. 

4) Write about anti-arrhythmic drugs in detail.

5) Write about potassium channel blockers. 

6) Discuss in detail about anti-hyperlipidimic drugs.