CARDIOVASCULAR-I

• Various drugs used to in cardiovascular diseases are-

1. ACE inhibitors
2. Angiotensin antagonist
3. Diuretics
4. Beta Blockers
5. Calcium channel blockers
6. Cardiac Glycosides
7. Trinitroglycerine
8. Others

• Various cardiovascular diseases-

1. Hypertension
2. Angina (stable,unstable,prinzmetal's angina)
3. Infarction
4. Heart failure(CHF,LVF) 

• La place Law- Ventricular wall tension=Ventricular pressure*Ventricular radius
• Starling's Law-Force of contraction of muscle is directly proportionality to the length of fiber before the onset of contraction.
• Cardiac Output is directly proportional to H.R,Venous return,Force of contraction and is inversely proportional to T.P.R
• Whenever Volume overload increases(Increased blood volume) or T.P.R increases,hypertrophy and remodeling in heart and blood vessels occur.This leads to Ventricular Hypertrophy and thickening of ventricular walls.As this happens,according to La place rule,wall tension increases,leading to reduce heart functioning.
• ACE inhibitors- Reduces T.P.R;Reduces Heart rate;Increases Cardiac output;Increases renin level and decreased aldosterone and ADH secretion;Increased loss of sodium and water(due to better renal perfusion),left ventricular remodelling.Side effects-Cough (bradykinin release),Fetopathic,First Dose hypotension,Hyperkalemia.
• Angiotensin antagonist-More potent with less side effects than ACE inhibitors.
• Beta Blockers-Decreases heart rate;force of contraction and Cardiac output;T.P.R initially increases(Alpha mediated vasoconstriction) but latter on T.P.R decreases(Due to reduced C.O);Decreases renin release.Effective as mild anti hypertensive,angina pectoris and after correction of MI to increase the life expectancy and prognosis.Cardioselective drugs(Beta 1 blockers) are more useful for treating angina.
• Calcium Channel Blockers-Various CCB available are as-VERAPAMIL,DILTIAZEM,NIFEDIPINE

VERAMPIL-Dilate arterioles and block alpha blockers-reduce T.P.R;Reduces heart rate(by reducing SA node and AV node conduction);Reduces myocardial contractility;Cardiac output remains normal by reflex sympathetic stimulation;Increases coronary blood flow.Should not be given along with the Beta blockers.

NIFEDIPINE-Dilate arterioles-Reduces T.P.R;Much higher sympathetic stimulation;less SA and AV node conduction reduction;H.R,contractility and C.O. increases due to sympathetic stimulation;Increases coronary blood flow.

DILTIAZEM-Less potent vasodilator;SA AND AV node depression;Modest negative inotropic effect.

• Diuretics-Increases loss of water,Sodium and potassium loss-Reduces preload(decreased blood volume),C.O and T.P.R(by loss of sodium).They potentate action of other antihypertensive drugs.

Various types of diuretics are- FUROSEMIDE,THIAZIDES,ACETAZOLAMIDE,Potassium sparing diuretics-SPIRINOLACTONE
FUROSEMIDE-They are very potent diuretics and act on the ascending loop of henle.They also account for the loss of sodium,calcium,potassium,magnesium.High ceiling diuretics are given only in -Renal faliure/insufficiency,CHF,hypertensive emergency otherwise thiazides are used.
THIAZIDES-Act on PCT and DCT.Avoid absorption of sodium.
ACETAZOLAMIDE-Acts on PCT and DCT,avoid absorption of sodium bicarbonate.Weak Diuretic
Potassium sparing Diuretics-They inhibit aldosterone sensitive Na/K exchange in collecting tubules.
Furosemide and thiazides causes hypokalemia and alkalosis whereas spirinolactone can lead to hyperkalemia and acidosis.

• Cardiac Glycosides-Eg.Digitalis.There main action is to reduce the heart rate and increasing the force of contraction there by increasing the cardiac output,keeping the demand of oxygen same.Adrenaline do the same but it increases the demand of oxygen too.Now a days its not used due to its high toxicity.
• Trinitroglycerine-They are the drugs that causes vasodilatation in the peripheral vessels,decreases venous return and thereby reducing the preload,They also reduce the oxygen demand and the force of contarction;TNG also reduces afterload by reducing the T.P.R;They also causes redistribution of coronary blood,thereby increasing blood to ischaemic area of heart.

The dilator effect on large coronary vessels is the main action of TNG,which is used in treating angina and ischemia.

• Other drugs-

ASPIRIN,CLOPIDOGREL,DIPYRIDAMOLE- Anti platelet drugs
STREPTOKINASE,ALTEPLASE-For thrombolysis

MORPHINE-For Analgesia

DIAZEPAM-Sedatives