Antihypertensives PDF Presentation by Prof Amos Massele 2025

ANTIHYPERTENSIVES Presenter: Prof Amos Massele MD ;PhD PHC 300 Pharmacology Dept 16 JAN 2025  Learning Objectives At the end of this presentation the learner should be able to: Define and classify hypertension To understand the nor...

ANTIHYPERTENSIVES Presenter: Prof Amos Massele MD ;PhD PHC 300 Pharmacology Dept 16 JAN 2025  Learning Objectives At the end of this presentation the learner should be able to: Define and classify hypertension To understand the normal regulation of BP, etiology of hypertension, and the diagnosis. To understand the basic pharmacology of Antihypertensive Agents: ACEIs, ARBs, Beta-blockers, CCBs, Diuretics, Sympatholytic, Direct vasodilators (MoA, PKs, PDs, and toxicity). To describe the concept of resistant hypertension and the resultant polypharmacy. To understand the management of hypertensive emergencies; pathophysiology, clinical presentation and treatment. Hypertension Definition Hypertension is sustained elevation of BP Systolic blood pressure  140 mm Hg Diastolic blood pressure  90 mm Hg  Important Equations Blood pressure = Cardiac output x Peripheral vascular resistance (BP = CO x PVR) Cardiac output = Heart rate x Stroke volume (CO = HR x SV) Long term regulation of BP  Diagnosis of Hypertension According to the European Society of Hypertension (ESH) diagnosis of hypertension is reached when a person has Systolic BP ≥140 mm Hg and/or diastolic BP ≥ 90 mm Hg The American cut-off for the definition of hypertension has been lowered to ≥130/80 mm Hg with BP range 130-139/80-89 mm Hg now classified as stage 1 hypertension Diagnosis is reached based on 3 separate office visits and severity of hypertension Some patients are affected by the white-coat effect In this case there may be need for ambulatory blood pressure measurement Home based blood pressure measurements may sometimes be useful  Types of hypertension CLASSIFICATION: - Primary hypertension (essential hypertension) - Secondary hypertension (10 – 15 % of patients)  Phaechromocytoma  Renal artery stenosis  Cushing’s syndrome  Narrowing of aorta (coarctation) - atheroma Isolated systolic hypertension (ISH) Isolated diastolic hypertension (IDH) Combined systolic and diastolic hypertension (Combined SDH)  OTHER Types of hypertension I.Hypertensive emergency/malignant hypertension: An accelerated form of severe hypertension associated with rising BP and rapidly progressing damage to vessels and end organs Often signaled by renal damage, encephalopathy, and retinal hemorrhage or by angina, stroke, or myocardial infarction Management:  Powerful vasodilators (nitropruside, fenoldopam or diazoxide) in combination with diuretics (frusemide) and β-blockers to lower blood pressure promptly  Further reduction is then pursued more slowly  II. Resistant hypertension (RH) This is SUSTAINED RISE IN BP despite the concurrent use of 3 antihypertensive drug classes, commonly including a long-acting CCB, ACEI or ARB, and a diuretic administered at maximally tolerated daily doses. RH also includes patients whose BP achieves target values on ≥4 antihypertensive medications. The diagnosis of RH requires assurance of antihypertensive medication adherence  Consequences of uncontrolled systemic hypertension Increases the risk of: Coronary thrombosis Strokes Renal failure (BP control is intimately related to the kidneys) Atherosclerosis  Persistently raised arterial blood pressure leads to hypertrophy of the left ventricle and remodeling of resistance arteries, with narrowing of lumen thus predisposing to arteriosclerosis Image of patient with stroke on physio---  GOAL OF TREAMENT OF HYPERTENSION: To reduce the risk of end-organ damage TO: - blood vessels in kidneys, heart, retina and brain may lead increased incidence of renal failure, coronary disease, cardiac failure, and stroke\ Hypertensions treatment options - Non -pharmacological - pharmacological  Non-pharmacological opportunities for the control of blood pressure Expected systolic BP Intervention Recommendation reduction (range) Maintain ideal body mass index (20- 5-10 mmHg Weight reduction 25kg/M²) per 10kg weight loss Eat diet rich in fruit, vegetables, low-fat Eating plan dairy products. Eat less saturated and 8 -14 mmHg total fat Reduce dietary sodium intake to Dietary sodium