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Home , Celiprolol, Nebivolol

CHAPTER Newer in

147 Anita Jaiswal

BETA BLOCKERS INHIBIT RESPONSES a. First generation (older, nonselective)-, MEDIATED THROUGH THE BETA RECEPTORS , , Propranolol introduced in 1963 was the first betablocker. b. Second generation (β1 selective)-metaprolol, , , , Since then drugs of this class have proliferated and diversified. c. Third generation(additional α blocking property and vasodilator property)- labetolol, carvidilol, Mechanism of action , 1. Reduction of adrenergic response mediated via β receptors. Need for improved beta blockers 2. Inhibition of renin release. Adverse effects of older agents 3. Inhibition of central nervous sympathetic 1. Bronchoconstriction. outflow,thereby inducing presynaptic blockade 2. Deliterious effects on lipid profile and insulin which in turn reduces the release of cathecholamines. sensitivity. 4. Reduction of venous return and plasma volume 3. No cardiovascular and cerebrovascular morbidity 5. Newer agents - generation of and mortality benefits (Messerli et al, The life reducing PVR, attenuation of pressor response to study, The carlberg et al, The ASCOT BPLA trial). cathecholamines with exercise and stress. 4. No significant control. Classification of beta blockers Third generation beta blockers (, Labetolol, 1. Solubility based Nebivolol) – a. Hydrophilic (atenolol,carvidilol,nebivolol) Labetolol b. Lipophilic— highly soluble(prapranolol), 1. Nonselective beta blocker. moderately soluble(metaprolol and ) 2. But has additional α blocking activity. 2. Selectivity based 3. No significant effect on rate and cardiac a. Nonselective (β1 and β2) output. 1. Without intrinsic sympathomimetic activity - 4. Specific use in pheochromocytoma and PIH. propranolol, sotalol, timolol 5. Available in injectable form so widely used in 2. With intrinsic sympathomimetic activity- pindolol management of hypertensive emergencies. 3. With additional α blocking property- labetolol, 6. But increase incidence of respiratory distress carvedilol, nebivolol. syndrome, sepsis and seizures in infants of labetolol treated PIH. b. Cardioselective (β1) metaprolol, atenolol, acebutolol, bisoprolol, esmolol, , Carvedilol celiprolol, nebivolol 1. Non selective beta blocker. 3. Time research based classification 2. Additional α blocking activity. Table 1: Comparison of Conventional and Newer Beta 3. Limited effects on heart rate and cardiac contractility. Blockers 4. Used in LV dysfunction following MI. Effects Conventional Newer 5. Chronic primary HTN. Bronchoconstriction + - 6. Useful in portal hypertension due to reduction in Dyspidemia, diabetes + - hepatic venous pressure gradient. Primary prevention of CV + _ 7. Vascular insulin sensitivity is preserved. risk 8. Increased coronary flow reserve and improved Core BP/ MAP reduction + _ endothelial function. CHAPTER 147 681 Arch 2012; 10:33. Ther Adv Endocrinol 2011; Curr Cardiol Rep 2014; 129:451–462. 2013; 26:218–226. Significantlyincreases urinary NO production). increased of excretion(indication nitrite and PROBE trial showed better decrease to in compared as group nebivolol LV mass by index mass and group Ramipril Nebivolol equally effective in reducing peripheral BP and augmentation index aliskerin. like quinapril and equally effectiveas patients valsartan with of reducing heart rate. advantage in hypertensive obstructive sleep apnea with Metab 2011; 2:65–79. Belge C, Hammond Hamelet J, J, Dubois-Deruy E, Beauloye of Manoury C, b3-adrenoceptors B, et neurohormone-induced hypertrophic remodeling through in al. cardiac Enhanced . Circulation expression myocytes attenuates Bhadada SV, Patel BM, Mehta AA, Goyal RK. β(3) receptors: β(3) RK. Goyal AA, Mehta BM, Patel SV, Bhadada role in cardiometabolic disorders. Elliott WJ, Childers WK. Shouldb blockersconsidered first-line no therapy for longer be the treatment of essential comorbidities? without hypertension 13:507–516. Courand PY, Lantelme P. Significance, prognosticand value management of heart rate in hypertension. Cardiovasc Dis 2014; 107:48–57. Cardiovasc Salles GF, Cardoso CR, Fonseca LL, Fiszman R, Muxfeldt ES. Prognostic significance of baseline heart hypertension: resistant in use beta-blocker with interaction rate and its a cohort study. Am J Hypertens Fretheim A, Odgaard-Jensen Njølstad I, Norheim J, OF, et al. Comparative Brørs effectiveness of antihypertensive O, for primary prevention of Madsen S, cardiovascular disease: systematic review and treatments meta-analysis. BMC Medicine multiple REFERENCES 14. 15. 16. 17. Newer β blockers nebivolol,carvidilol have comparable control to regards with ACEI/ARB and CCB with efficacy risk. reduction of cardiovascular of hypertension and Still more clinical these agents. understanding regarding trials are required to have better 2. 1. 3. 4. 5. 6. c levels in all c levels 1 Also acts as a NO donor from endothelium (due to stimulation of endothelial NO synthase) produces vasodilatation. endothelial function. Improve Anti oxidant property (directly reacts oxygen species). reactive radicals scavenging with free Effective loweringand MAP of central than in aortic atenolol(both lowering equally brachial pressure pulse effective stiffness). pressure and aortic Provides relief in intermittent claudication. Significantly lowers sitting BP (SBPmild to moderate HTN). and DBP in Single dose(5-20mg) therapy better. so compliance is Specifically used this in older age group tends to patients(> have more systolic 62yrs) blood pressure as combination in effective very monotherapy, Besides with diuretic,CCB and other antihypertensives. profile. effect Favourable adverse Evening dosing significantlynight time and 24 hr BP and lowers SBP prewaking called day time, morning surge. In prehypertensives also central aortic systolic,diastolic BP and MAP significantly reduces Highly selective β1 blockers. Highly selective groups except non white and no black) non white and groups except Added therapy with carvedilol in diabetic patients has shown microalbuminuria. reduced TG, total cholesterol and Lowering Lowering mass LV index and (as LVH compared to metolor). Better glycemic effect/metabolic effect in diabetics as compared to metolor, best in both white and female sub group.(metolor increased HbA 11. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 2. Nebivolol Nebivolol 1. 9. 10.