3rd Class Flashcards
0
Q
Dobutamine
A
A= adrenopositive drug, selective beta1 receptor agonist B= activates mainly beta1 receptors of heart--> increased cAMP(thru the action of adenylyl cyclase)--> increases contractility with little effect on heart rate and beta2 receptors--> increases CO. Does not Cause release of NE as dopamine C= used in case of inotrophic support in cardiomyopathies, septic shock, cardiogenic shock, acute decompensated heart failure, intermittent therapy in chronic heart failure reduces the symptoms
1
Q
Digoxin
A
A= cardiac glycoside, digitalis, class 5 antiarrhytmic B= inhibits Na+/K+/ATPase membrane pump--> increase in i/c Na+ levels (and decrease I/c K+ levels). The NCX in turn tries to extrude the sodium and in doing so, pumps in more calcium. Increased ca2+ levels promotes activation of contractile proteins of cardiac sarcomere--> increases cardiac contractility (positive inotrophic and little batmotropic effects) cardiac parasympathomimetic effects (slowed HR, slow AV conduction). Also shortens APD (by increased potassium conductance due to increased i/c calcium levels) and decreasing the maximal diastolic potential C= chronic heart failure, rapid ventricular rate in afib, congestive cardiac insufficiency, arrhytmias
2
Q
Spironolactone
A
A= synthetic steroid, aldosterone antagonist, potassium sparing diuretic, antihypertensive B= blocks cytoplasmic mineralocorticoid aldosterone receptors in collecting tubules of nephrons --> increased salt and water excretion while potassium is retained. Also blocks androgen receptors--> anti androgenic effects C= chronic heart failure, aldosteronism (conns syndrome, adrenal tumors), hypertension, edema in patients with congestive heart failure and nephrotic syndrome, hypokalemia,
3
Q
Hydrochlorothiazidine
A
A= antihypertensive drugs, thiazide-type diuretics B= acts on the distal convulated tubules of kidneys and inhibits the sodium-chloride symporter leading to retention of water in the urine (inhibits sodium reabsorption). In this way, blood plasma volume is reduced, and thus blood pressure is reduced (due to decreased preload) C= Heart failure, hypertension, oedema
4
Q
Enalapril
A
A= antihypertensive drug, ACE inhibitor B= acts by blocking the ACE that normally hydrolyes angiotensin I to angiotensin II and inactivates bradykinin (plasma kininase). this leads to decreased amount of angiotensin II and increased amount of bradykinin(vasodilator) -->vasodilation and inhibition of aldosterone secretion (reduces peripheral vascular resistance and decreases sodium and water retention) --> decreases bp C= Hypertension, heart failure, myocardial infarction, left ventricular dysfunction, diabetic nephropathy
5
Q
Irbesartan
A
A= non-peptide tetrazole derivative, ARB, antihypertensive, B= selective competetive antagonist of angiotensin AT1 receptors--> arteriolar dilataiton, decreased aldosterone secretion--> increased sodium and water excretion, reduction in secretion of vasopressin--> decrease of bp C= hypertension, diabetic nephropathy, congestive heart failure
6
Q
Nebivolol
A
A= adrenonegative drug, cardioselective beta1 antagonist without ISA, class 2 antiarrhytmic B= blocks beta 1 receptors + increased production of NO (further vasodilation, ERF) --> lowers heart rate and pressure. Also prevents release of renin. At high conc it may bind to beta2 receptors C= angina pectoris, hypertension, arrhythmias (SV/V)
7
Q
Procainamide
A
A= class 1a antiarrhytmic drug B= Ina and Ikr blockade--> by blocking sodium channels it slows the upstroke of f AP, slows conduction and prolongs Qrs. It also prolongs APD by nonspecific blockade of potassium channels--> prolongs refractory period C= most atrial and supraventricular/ventricular arrhytmias, ventricular arrhytmias associated with acute myocardial infarction
8
Q
Lidocaine
A
A= class 1b antiarrhytmic, local (amide type) anaesthetics, Cardiac depressant B= blocks activated and inactivated sodium channels with rapid kinetics, depresses ventricular excitability and the stimulation threshold for ventricular is increased during diastole (shortens repolarization and slows the depolarization process by acting in stage 4 of AP) C= arrhytmias, termination of ventricular tachycardia/ arrhytmias, prevention of afib Local/regional anaesthesia (= surface anaesthesia, infiltration anaesthesia, spinal/lumbar anaesthesia, epidural block)
9
Q
Phenytoin
A
A= antiseizure drug, cyclic ureides, class 1b anti arrhytmic B= blocks high frequency firing neurons though action on voltage gated Na+ channels, decreases synaptic release of glutamate. Slows depolarization process and shortens repolarization by acting on stage 4 of an AP C= generalized tonic-clonic seizures, partial seizures, ventricular arrhytmias
10
Q
Verapamil
A
A= non-DHP calcium channel blocker, class 4 antiarrhytmic drug B= blocks L type calcium channels--> inhibits influx of e/c calcium across myocaridum and vascular SMC--> reduces cardiac rate and output(negative chrono and dromotropic effects), reduces peripheral vascular resistance C= hypertension, angina, supraventricular tachycardia and arrhytmias
11
Q
Diltiazem
A
A= non-DHP calcium channel blocker, class 4 antiarrhytmic drug B= blocks L type calcium channels--> inhibits influx of e/c calcium across myocaridum and vascular SMC--> reduces cardiac rate and output(negative chrono and dromotropic effects), reduces peripheral vascular resistance C= hypertension, angina, supraventricular tachycardia and arrhytmias
12
Q
Propranolol
A
A= adrenonegative drug, non cardioselective beta blocker without ISA, class 2 antiarrhytmic drug B= blocks beta1and 2 receptors --> reduction in caricac ino-chronotropic-batmo-dromotropic effects as well as blood pressure and reflex orthostatic hypotension. Prevents sympathetic cardiac stimulation/ and reduce plasma renin secretions C= angina pectoris, hypertension, tachycardia, heart failure, migraine, anti-anxiety activity (blocks serotonin receptors) acute myocardial infarction, hyperthyroidism, pheochromocytoma
13
Q
Sotalol
A
A= non-cardioselective beta blocker, class 3 antiarrhytmic drug B= prolongs AP by blocking potassium channels in cardiac muscle--> prolongs repolarization-->lengthening of QT interval and decreasing automaticity. By blocking beta1 receptors causing negative effects on heart and beta2 receptors in vascular SMC and bronchospasm C= life threatening ventricular arrhytmias, maintenance of sinus rhythm in patients with afib, supraventricular and ventricular arrhytmias in pediatric age group
14
Q
Metoprolol tartrate
A
A= adrenonegative drug, selective beta1 antagonist without ISA B= blocks beta1>beta2 (cardioselective) --> reduces cardiac output (negative ino/batmo/chrono/dromotropic effects) C= angina pectoris, hypertension, arrhythmias, migraine, stenocardia, acute myocardial infarction, chronic heart failure!
