Arterial Hypertension Assoc. Prof. MUDr. Markéta Bébarová, Ph.D. Dept. of Physiology, Faculty of Medicine, Masaryk University Definition and Consequences rtenal hypertension - chronic increase ot the systemic blood pressure. Symptoms indistinctive and nonspecific in the first stages of hypertension ->• almost 50% of the hypertensive patients do not know about their hypertension! If not diagnosed in time and adequately treated, arterial hypertension results in: ❖ overload of the left ventricle (hypertrophy, heart failure) ❖ arteriosclerosis increased risk of the myocardial infarction increased risk of the stroke the renal failure, etc. Hypertension significantly shortens the life span. Definition and Consequences Arterial hypertension - chronic increase of the systemic blood pressure. Table 1 Definitions and classification of blood pressure (BP) levels (mmHg) Category Systolic Diastolic Optimal <120 and <80 Normal High normal Grade 1 hypertension Grade 2 hypertension Grade 3 hypertension Isolated systolic hypertension 120-129 130-139 140-159 160-179 >180 >140 and/or and/or and/or and/or and/or and 80-84 85-89 90-99 100-109 >110 <90 Guidelines for the management of arterial hypertension. Eur Heart J 2007;28:1462-1536. Methods of blood pressure measurement Proper way of blood pressure measurement Definition and Consequences Arterial hypertension - chronic increase of the systemic blood pressure. Table 1 Definitions and classification of blood pressure (BP) levels (mmHg) Category Systolic Diastolic Optimal <120 and <80 1 Normal 120-129 prehypertension____ I High normal K yK 130-139 and/or and/or 80-84 85-89 Grade 1 hypertension Grade 2 hypertension Grade 3 hypertension Isolated systolic hypertension 140-159 160-179 >180 >140 and/or and/or and/or and 90-99 100-109 >110 <90 Guidelines for the management of arterial hypertension. Eur Heart J 2007;28:1462-1536. Definition and Consequences Arterial hypertension - chronic increase of the systemic blood pressure. Table 1 Definitions and classification of blood pressure (BP) levels (mmHg) Category Systolic Diastolic Optimal Normal High normal Grade 1 hypertension <120 120-129 130-139 140-159 and and/or and/or and/or <80 80-84 85-89 90-99 Grade 2 hypertension Grade 3 hypertension Isolated systolic hypertension 160-179 >180 >140 and/or and/or and 100-109 >110 <90 Guidelines for the management of arterial hypertension. Eur Heart J 2007;28:1462-1536. Definition and Consequences Stratification of cardiovascular risk Blood pressure (mmHg) Other risk factors, OD or Disease Normal SBP 120-129 or DBP 80-84 High normal SBP 130-139 or DBP 35-39 Grade 1 HT SBP 140-159 or DBP 90-99 Grade 2 HT SBP 160-179 or DBP 100-109 Grade 3 HT SBP>180 or DBP>110 No other risk factors Average risk Average risk i Low added risk i Moderate added risk High added risk 1-2 risk factors Low added risk Low added risk t rvlo derate ffdded risk Moderate added risk Very high added risk 3 or more risk factors, MS, OD or Diabetes Moderate added risk > HighX' addeS risk High added risk High added risk Very high added risk Established CV or renal disease Very high added risk Very high added risk Very high added risk Very high added risk Very high added risk Guidelines for the management of arterial hypertension. Eur Heart J 2007;28:1462-1536. _ Definition and Consequences in children and adolescents - special percentile tables Factors Determining Blood Pressure * T cardiac output T —> volume-loading (hyperdynamic, volume dependent) h. * T total peripheral resistance resistance (non-volume dependent) h i- C = AV / AP i compliance -> isolated systolic hypertension P = CO . TPR heart CO = SV.HR HR is guided by sympathetic and parasympathetic system SV depends on: 1 .venous return (blood volume, tonus of veins) 2.contractilitv 3.peripheral »ressure P A. Cardiovascular system veins blood reservoire 64% Vehs 9% Lungs Heart" 5% (diastole) s% J% Capillaries Lesser arteries Greater and arterioles arteries Volume distribution Brain: Q = 13% 47% Lesser a rteries and arterioles .7% Pulmonary artery Blood pressure: 25/lOmmHg (mean: 15mmHg) 27% Capillaries Resistance distribution in system ic circu lation Aorta Blood pressure: 120/80 mmHg (mean: lOOmmHg) Low-pressure system (reservo ir function) Liver and gastrointestinal tract Q =24% Vor 23% Skeletal muscle: Q = 21% V0,= 27% w ■ High-pressure system (supply function) Blood Flow to organs as % of cardiac output (resting CO 5.6 L/min atbodyweightof 70 kg) Vor 7% Skin and other organs Organ O; consumption as % of total Oi consumption (total at rest- 0.25 L/min) Hi espopoulos, Color Atlas of Physiology © 2003 Thieme kidneys regulation of blood volume P = CO . TPR ! arterioles regulation of TPR kidneys regulation of blood volume also TPR (RAS) heart CO = SV.HR HR is guided by sympathetic and parasympathetic system SV depends on: 1 .venous return (blood volume, tonus of veins) 2.contractilitv 3.peripheral pressure i—A. Cardiovascular system veins blood reservoire 64% Vehs 9% Lungs Heart 5% (ttastole) s% J% Capillaries Lesser arteries Greater and arterioles arteries Law-press ure system (reservo ir fu nction) Blood Flow to organs as % of cardiac output (resting CO 5.6 L/min at body weig ht of 70 kg) Skin and other organs Despopoulos; Color Atlas of Physiology © 2003 Thieme B. Vasoconstriction and vasodilatation Pressor areo la Neuronal Sympathetic 1b Neuronal P = CO . TPR Sympathetic \ tonus y Parasympathetic system (salivary glands, genitalia) M Ad H\ K+ etc. _ NOf PGE2,PGI2f 2b local Bradykinin, a kallidin ADH(Vi). epinephrine, angiotensin II 3a Hormonal Epinephrine (P2) Acetylcholine (M), ATP, 3b histamine (Ht), Hormonal endothelin-1 (ETB) Despopoulos, Color Atlas of Physiology © 2003 Thieme P = CO . TPR heart CO = SV.HR HR is guided by sympathetic and parasympathetic system SV depends on: 1 .venous return (blood volume, tonus of veins) 2.contractilitv 3.peripheral pressure ,— A. Cardiovascular system veins blood reservoire 64% Veins 3% Lungs Heart" 5% (diastole) 9% J% Capillaries Lesser arteries Greater and arterioles arteries Low-press ure system (reservo ir fu nction) Blood Flow to organs as % of cardiac output (resting CO 5.6 L/min atbodyweightof 70 kg) Skin and other organs Despopoulos, Color Atlas of Physiology © 2003 Thieme aorta and big elastic arteries compliance !) arterioles regulation of TPR kidneys regulation of blood volume, also TPR (RAS) P = CO . TPR heart CO = SV. HR HR is guided by sympathetic and parasympathetic system SV depends on: 1 .venous return (blood volume, tonus of veins) 2.contractilitv 3.peripheral pressure ,— A. Cardiovascular system veins blood reservoire aorta and big elastic arteries compliance Blood flow to organs as % of cardiac out nut (resting CO 5.6 L/min at bodyw-eightof 70 kg) Skin and other organs Organ Oj consumption n% of total Oi consumption (total at rest ~- 0.25 L/ min) espopoulos; Color Atlas of Physiology © 2003 Thieme j arterioles 3 regulation of TPR regulation of blood volume - kidneys - thirst - ADH heart CO = SV. HR HR is guided by sympathetic and parasympathetic o\/o+om i— A. Cardiovascular system SVi (k tc 64% Veins .7% 3% Lungs Heart 5%. (diastole) 8ffi 7S Capillaries Lesser arteries Greater and arterioles arteries Volume di it ri but ion 47% Leaser arteries and arterioles P = CO . TPR 27% apillaries 19%. Arteries 7% Veins ance distribution in svsArri ic circu lation aorta and big elastic arteries Pathophysiology of hypertension is very complex, thus, usually hard to be analyzed in a concrete patient! 3.peripheral >ressure veins blood reservoire ^Se^ncl™ gastrointestinal tract: Q =24S Vo? 23S Skeletal muscle Vn = 17% qani utriut Blood How to organs a; o ol cardiac out nut (resting CO 5.6 L/miri at bodyweightcf 70 kg) Skin and other organs ./ Orga n Oj consumption ai% of total O2 consumption (total at rest- 0.25 L/mirt) Despopoulos, Color Atlas of Physiology © 2003 Thieme 1 regulation of TPR regulation of blood volume - kidneys - thirst - ADH A. Essential (primary) hypertension • „hypertension of an unknown origin" • 90-95% B. Secondary (symptomatic) hypertension • symptom of another primary disease with identifiable cause Essential Hypertension strong hereditary tendency in some patients (polygenic ground) provoking factors: • excess weight gain, obesity - account for about 65-70% of the risk for developing of essential hypertension • sedentary lifestyle New clinical guidelines recommend increased physical activity and weight loss as the first step in treating most patients with the essential hypertension. • stress (namely mental) • excessive sodium intake (interpopulation studies -Eskimos vs. people living in the North Japan) Definition and Consequences Arterial hypertension - chronic increase of the systemic blood pressure. Table 1 Definitions and classification of blood pressure (BP) levels (mmHg) Category Systoli c Diastolic Optimal <120 and <80 Normal 120- 129 and/or 80- 84 High normal 130- 139 and/or 85- 89 Grade 1 hypertension 140- 159 and/or 90- 99 Grade 2 hypertension 160- ■179 and/or 100- 109 Grade 3 hypertension >180 and/or >110 Isolated systolic >140 and <90 hypertension Guidelines for the management of arterial hypertension. Eur Heart J 2007;28:1462-1536. Essential Hypertension ysionc i-iypenension t systolic and pulse pressure in the elderly age-dependent remodelling of the wall (less elastic and more collagen fibres) -> t stiffness, ~l compliance: of elastic arteries 1. -> J, distension of elastic arteries during the systole -> steeply | arterial systolic pressure + l blood volume (and also pressure) in arteries during the diastole 2. -» I pulse wave velocity endothelial dysfunction Essential Hypertension reatmen New clinical guidelines recommend increased physical activity and weight loss as the first step in treating most patients with EH. Decrease of sodium and increase of potassium intake, relaxation ... vasodilatory drugs | P - CO . TPR • i TPR, some of them | renal blood flow as well (ACEI) a. by inhibiting sympathetic nervous system (sympatolytics) b. by directly paralyzing the smooth muscle of the renal vasculature (vasodilatory agents or calcium channel blockers) c. by blocking action of the renin-angiotensin system on the renal blood vessels or tubules (inhibitors of angiotensin l-converting enzyme, ACEI) natriuretic (diuretic) drugs • i renal tubular reabsorption of salt and water -> j, CO (by blocking the active transport of sodium through the tubular wall) A. Essential (primary) hypertension • „hypertension of an unknown origin" • 90-95% B. Secondary (symptomatic) hypertension • symptom of another primary disease with identifiable cause Secondary Hypertension enai nypenension Prerenal causes - Renovascular hypertension Acute and chronic diseases of the renal parenchyma • Postrenal causes (renal vein trombosis, urinary tract obstruction) Renin-producing renal tumor Endocrine hypertension Adrenocortical hyperfunction (Cushing s, Conn's, adrenogenital sy) Sympatoadrenal hyperfunction (pheochromocytoma) • Exogenic hormones (gluko-, mineralocorticoids, sympatomimetics) Hyperthyroidism Acromegaly Coarctation of the aorta Hypertension in preeklampsia Neurogenic hypertension