Kórélettan jegyzet (Anna)

1. Essential Hypertension

  • Definition: Essential hypertension is a multifactorial disorder characterized by elevated blood pressure without identifiable cause.

  • Risk Factors:

    • Unmodifiable:

      • Positive family history

      • Male gender

      • Age

      • Pregnancy-induced hypertension (preeclampsia)

    • Modifiable:

      • Smoking

      • Obesity

      • Diabetes

      • Stress

      • Excessive alcohol consumption

      • Sedentary lifestyle

      • High sodium intake

      • Poor sleep quality, night shifts

      • Obstructive sleep apnea

2. Mechanisms Involved in Hypertenison Development

  1. Genetics and Heritability:

    • Heritability ranges from 35-50%.

    • Approximately 120 loci linked to hypertension, revealing risk patterns.

  2. Neuroendocrine Dysfunction:

    • Renin-angiotensin system (RAS):

      • Impaired renin secretion from kidneys.

      • Increased sympathetic tone.

      • Local RAS over-activation in endothelial cells leads to:

        • Endothelial dysfunction

        • Oxidative stress

        • Pro-fibrotic and pro-inflammatory effects.

        • Accelerated vascular remodeling.

    • Natriuretic peptides:

      • Promote vasodilation and natriuresis, reducing blood pressure.

      • ANP and BNP secreted due to atrial stretch, deficiency leads to hypertension.

    • Endothelium:

      • Oxidative stress decreases bioavailability of NO (due to reactive radicals).

      • Increased endothelin levels lead to vasoconstriction.

    • Sympathetic Nervous System:

      • Increases vascular resistance, heart rate, and renal renin release leading to long-term damage.

  3. Salt Sensitivity:

    • High salt intake associated with significant systolic blood pressure increase (10 mm Hg/10g salt).

    • Mechanisms include:

      • NP deficiencies, RAS over-activation, sympathetic system dynamics, and endothelial dysfunction.

  4. Aging of Blood Vessels:

    • Increased media to lumen ratio.

    • Thickening of tunica media and loss of elastin, causing vascular stiffness.

3. Treatment Options for Essential Hypertension

  • Non-pharmacological Treatment (for mild cases):

    • Reduce sodium intake.

    • Increase potassium intake.

    • Reduce alcohol consumption.

    • Quit smoking.

    • Regular physical activity and weight loss.

    • Balanced diet rich in lean meats, vegetables, fruits, and stress management practices.

  • Pharmacological Treatment (for severe cases):

    • First-line medications:

      • Diuretics (reduce volume overload).

      • DHP calcium channel blockers (reduce vasoconstriction).

      • ACE inhibitors (reduce angiotensin II levels).

    • Second-line medications:

      • Alpha-1 receptor blockers (prevent vasoconstriction).

      • Non-DHP calcium channel blockers (reduce heart contractility and frequency).

4. Heart Failure Overview

  • Definition: A syndrome where the heart's pumping function declines progressively, resulting in systemic and organ-level changes, potentially leading to death.

  • Clinical Importance:

    • Most common diagnosis in individuals older than 65.

    • Increased prevalence with poor prognosis; ~50% 5-year survival rate.

5. Classification of Heart Failure

  • Types:

    • Acute vs. Chronic.

    • Forward vs. Backward failure.

    • Systolic vs. Diastolic.

    • Left vs. Right-sided heart failure.

  • Symptoms:

    • Left-sided failure leads to pulmonary congestion (dyspnea).

    • Right-sided failure causes edema and congestion in organs like the liver.

  • Ejection Fraction Classifications:

    • Healthy: EF ≥ 75%.

    • HFrEF (Heart Failure with reduced EF): EF < 40%.

    • HFmrEF (mid-range EF): EF 40-49%.

    • HFpEF (preserved EF): EF ≥ 50%.

6. Causes of Heart Failure

  • Ischemic heart disease, hypertension, diabetes, cardiomyopathy, and others.

7. Exacerbating Factors

  • Increased cardiac workload due to fever, hyperthyroidism, renal failure, and excessive sodium intake leading to acute heart failure.

8. Diagnosis of Heart Failure

  • Based on medical history, symptoms, physical examination, and supportive diagnostic tests (ECG, chest X-ray, echocardiography, biomarkers such as BNP).

9. Systolic and Diastolic Heart Failure Effects

  • Systolic Dysfunction: Reduced contractility causing a decrease in stroke volume.

  • Diastolic Dysfunction: Impaired chamber filling leading to increased stiffness.

10. Treatment of Heart Failure

  • Medical therapy focusing on symptomatic and cause-targeted approaches (both pharmacological and non-pharmacological).

  • Common treatments include diuretics for fluid management, and various agents targeting the renin-angiotensin system.

  • Devices and Surgery may be required for some patients (e.g., heart transplants, LVADs).

11. Obesity Overview

  • Definition: Disease characterized by excessive fat accumulation that may impair health.

  • Prevalence:

    • Global issues of obesity with increasing rates since 1990.

  • Causes:

    • Genetic, environmental, and lifestyle factors affecting energy balance increased body weight.

12. Pathophysiology of Obesity

  • Physiological Changes in Adipose Tissue:

    • Secretion of adipokines influencing metabolic pathways.

  • Morphological Changes:

    • Hyperplasia and hypertrophy of adipocytes impact body metabolism.

  • Consequences:

    • Comorbidities, including diabetes and cardiovascular disease.