Pathophysiology 1: Overview

Heart failure is a condition in which the heart cannot pump blood as effectively as it should, resulting in a reduced amount of blood being supplied to the organs in the body.

Causes of heart failure:

• Heart failure due to volume overload:

• Left heart failure: Excessive blood return to the left ventricle due to diseases such as mitral valve regurgitation, aortic valve regurgitation.

• Right heart failure: Increased pulmonary resistance due to diseases such as pulmonary fibrosis, pulmonary stenosis; or volume overload due to congenital defects such as ventricular septal defect, atrial septal defect, patent foramen ovale.

• Heart failure due to increased resistance:

• Left heart failure: High resistance in the systemic circulation due to diseases such as hypertension, aortic stenosis, coarctation of the aorta; or volume overload due to excessive blood return to the left ventricle (mitral valve regurgitation, aortic valve regurgitation).

• Right heart failure: Increased resistance in the lungs due to diseases such as pulmonary fibrosis, pulmonary stenosis.

Syncope and coma:

• Similarities: Both are states of unconsciousness.

• Differences: Syncope occurs suddenly and usually recovers quickly. Coma occurs gradually due to a pathological process and does not recover spontaneously.

Causes of hypotension:

• Infection, intoxication, acidosis.

• Sudden change in posture.

• Rapid and excessive removal of ascites.

Signs of edema in right heart failure:

• Peripheral edema: Soft, low edema due to increased peripheral venous pressure.

Atherosclerosis:

• Location of damage: Intima of large and medium arteries.

• Mechanism: Deposition of cholesterol in the intima layer causes degenerative damage, leading to calcium deposition, inflammation, ulceration, protrusion, thrombosis, and narrowing of the lumen.

• Causes: Due to disorders of lipoprotein (lipid + protein) metabolism, lipid transport and lipid-soluble substances.

• Main risk factor: LDL-C.

• Protective factor: HDL-C.

Classification of heart failure:

• 4 ways: Severity, extent, progression, mechanism.

Cardiac output: The amount of blood pumped out with each heartbeat.

Cardiac index: The amount of blood pumped out by the heart per minute.

Causes of arteriovenous malformations: Congenital defect or trauma.

Causes of narrowing of the artery after the elbow: Due to atherosclerosis, gender, age, history, and sedentary lifestyle. It can also be due to hypertension, diabetes, obesity, and lipid disorders.

Classification of heart failure by severity:

• Stage I: The heart can still meet the blood supply needs.

• Stage II: Shortness of breath during mild activity.

• Stage III: Shortness of breath during self-care.

• Stage IV: The heart cannot supply the minimum amount of blood even at rest.

Classification of heart failure by progression:

• Acute heart failure: Rapid, sudden onset, the heart does not have time to form adaptive measures.

• Chronic heart failure: Gradual and prolonged, the heart has time to form adaptive mechanisms.

Manifestations of left heart failure:

• Shortness of breath, cardiac asthma, acute pulmonary edema.

Manifestations of right heart failure:

• Hepatomegaly, peripheral edema, cyanosis of skin and mucous membranes, oliguria, increased diastolic blood pressure.

Nutmeg liver: Severe heart failure leads to liver fibrosis and degeneration.

Hypertension: Blood pressure measured twice after resting for 10-15 minutes, systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg.

Blood pressure: HA = P = Q * R

• HA: Blood pressure

• P: Pressure

• Q: Cardiac output

• R: Peripheral resistance

Cardiovascular collapse: Sudden dilation of the vascular system, before it can respond, blood pressure = 0. The heart pumps empty with severe brain hypoxia.

Shock symptoms: Disturbances in microcirculation lead to hypoxia in the brain and heart.

Symptoms of right and left heart failure:

• Specific information needs to be added to describe the symptoms of right and left heart failure.

Note: This article provides general information about pathophysiology 1. However, it cannot replace the advice of a medical professional. Consult a doctor for proper diagnosis and treatment.