CV Function Across the Life Span

CV Function across the Life Span

Aging and the Cardiovascular System

  • Cardiovascular Disease:

    • Most common cause of morbidity and mortality in older adults in Western society and other parts of the world.

  • Age as a Risk Factor:

    • Age is a primary driver of cardiovascular risk.

  • Physiological Changes with Age:

    • Myocardial and blood vessel stiffening.

    • Changes in neurogenic control over vascular tone.

    • Increased occurrence of atrial fibrillation.

    • Loss of exercise capacity.

    • Left ventricular hypertrophy and fibrosis.

  • Management and Improvement:

    • With active risk reduction, physical activity, and disease management, older adults can achieve markedly improved cardiovascular health.

Alterations of Cardiovascular Function in Children

Congenital Heart Disease

  • Definition:

    • Congenital Heart Disease (CHD) is a structural abnormality of the heart and/or great vessels that is present at birth.

  • Incidence:

    • Varies from 0.8% to 1.2% of live births worldwide.

    • Only 15% of cases can be attributed to a specific cause despite various environmental and genetic risk factors.

  • Environmental Factors Associated with CHD:

    • Infections.

    • Metabolic disorders.

    • Drugs.

    • Peripheral conditions.

Genetic Factors

  • Specific chromosomal aberrations linked to CHD have been identified.

  • The incidence of CHD is three to four times higher in siblings of affected children.

  • Diagnosis and management improvements include:

    • Use of fetal echocardiography for early detection.

    • Early interventional catheterization techniques.

    • Neonatal pulse oximetry pre-discharge screening.

    • Refined surgical repair methods.

Classification of Congenital Heart Disease

  1. Acyanotic Congenital Heart Disease

    • Increased pulmonary blood flow:

      • Atrial septal defect (ASD)

      • Ventricular septal defect (VSD)

      • Patent ductus arteriosus (PDA)

      • Atrioventricular canal defect

    • Obstruction to blood flow from ventricles:

      • Coarctation of the aorta

      • Aortic stenosis

      • Pulmonic stenosis

  2. Cyanotic Congenital Heart Disease

    • Mixed blood flow:

      • Tetralogy of Fallot

      • Tricuspid atresia

      • Transposition of the great arteries

      • Total anomalous pulmonary venous return

      • Truncus arteriosus

      • Hypoplastic left heart syndrome

Shunts

  • Normal Configuration:

    • Right atrium (RA)

    • Left atrium (LA)

  • Atrial and Ventricular Septal Defects Illustration

    • Illustration showing the flow of blood between atria and ventricles affected by septal defects.

Defects with Increased Pulmonary Blood Flow

  1. Patent Ductus Arteriosus (PDA):

    • Failure of the fetal ductus arteriosus (DA) to close within hours after birth.

    • Particularly affects premature infants and those born with asphyxia, and higher altitude birth settings, leading to lower blood oxygen concentrations.

  2. Atrial Septal Defect (ASD):

    • An opening in the septal wall between the two atria allows blood to shunt from the left atrium (LA) to the right atrium (RA).

    • It is a common form of CHD with significant mortality and morbidity if untreated.

  3. Patent Foramen Ovale (PFO):

    • An opening in the atrial septal wall that is part of normal fetal circulation, designed to bypass pulmonary circulation in utero. Typically closes after birth.

  4. Ventricular Septal Defect (VSD):

    • An opening of the septal wall between the ventricles.

    • VSDs are one of the most common types of congenital heart defects, accounting for 10% to 40% of all CHDs.

Defects With Decreased Pulmonary Blood Flow

  1. Tetralogy of Fallot (TOF):

    • Occurs in 5% to 10% of all congenital heart disease and is the most common cyanotic heart defect.

    • Consists of four defects:

    1. Large Ventricular Septal Defect (VSD)

    2. Pulmonary Stenosis (PS)

    3. Overriding aorta straddling the VSD

    4. Right Ventricular Hypertrophy (RVH)

Mixing Defects

  • Transposition of the Great Arteries:

    • Condition in which the great vessels arise from incorrect ventricles; specifically, the pulmonary artery (PA) exits the left ventricle (LV) and the aorta exits from the right ventricle (RV).