Cardiovascular Disease and Cancer: Overview

Introduction

This chapter explores the prevalence, risk factors, prevention, and treatment of cardiovascular disease (CVD) and cancer, two leading causes of death in the United States and globally. Understanding these conditions is essential for personal health management and public health awareness.

Cardiovascular Disease (CVD)

Definition and Burden

• Cardiovascular disease (CVD) encompasses diseases of the heart and blood vessels, including hypertension, coronary heart disease (CHD), heart failure, stroke, and congenital defects.

• Over one-third of American adults suffer from one or more types of CVD.

• CVD, especially ischemic heart disease and stroke, is the leading cause of death worldwide.

Ideal Cardiovascular Health (ICH)

ICH is defined by the absence of clinical indicators of CVD and the presence of optimal behavioral and health metrics.

• Behaviors:

  • Not smoking

  • Sufficient physical activity

  • A healthy diet

  • Appropriate energy balance and normal body weight

• Health Factors:

  • Optimal total cholesterol without medication

  • Optimal blood pressure without medication

  • Optimal fasting blood glucose without medication

Prevalence by Age and Sex

Prevalence of CVD increases with age and is generally higher in men than women until older age groups.

Cardiovascular System Anatomy and Physiology

Main Components

• Heart: Four chambers: two upper atria (receive blood) and two lower ventricles (pump blood).

• Arteries: Carry oxygenated blood away from the heart (except pulmonary arteries).

• Veins: Carry blood back to the heart.

• Capillaries: Permit exchange of gases, nutrients, and waste products with body cells.

• Sinoatrial node (SA node): Natural pacemaker of the heart.

• Valves: Regulate blood flow within the heart.

Blood Flow Within the Heart

• Deoxygenated blood enters the right atrium, moves to the right ventricle, and is pumped to the lungs via pulmonary arteries.

• Oxygenated blood returns to the left atrium, moves to the left ventricle, and is pumped to the body via the aorta.

Major Types of Cardiovascular Disease

Hypertension

• Systolic blood pressure: Pressure during heart contraction.

• Diastolic blood pressure: Pressure during heart relaxation.

Atherosclerosis and Peripheral Artery Disease (PAD)

• Atherosclerosis (CAD): Hardening and narrowing of arteries due to plaque buildup.

• Peripheral artery disease (PAD): Atherosclerosis in lower extremities.

Coronary Heart Disease (CHD)

• Most common and deadly form of CVD.

• Caused by blood clots or narrowed arteries reducing oxygen flow.

Arrhythmias

• Arrhythmia: Irregular heart rhythm due to faulty electrical impulses.

• Tachycardia: Abnormally fast heartbeat.

• Bradycardia: Abnormally slow heartbeat.

Angina Pectoris

• Chest pain due to insufficient oxygen supply to heart muscle.

• Treatment includes rest, drugs, calcium channel blockers, and beta-blockers.

Cardiomyopathy and Heart Failure

• Congestive heart failure: Heart cannot circulate blood effectively, leading to fluid buildup and symptoms like shortness of breath and fatigue.

Stroke (Cerebrovascular Accident)

• Interruption of blood supply to the brain.

• Transient ischemic attacks (TIAs): Brief interruptions causing temporary symptoms (dizziness, weakness, numbness, memory loss, blurred vision, slurred speech).

Risk Factors for Cardiovascular Disease

Modifiable Risks

• Avoid tobacco

• Reduce saturated fat intake

• Eat a heart-healthy diet (low sodium, high fiber, plant sterols)

• Maintain healthy weight

• Exercise regularly

• Control diabetes and blood pressure

• Manage stress and improve sleep

Nonmodifiable Risks

• Heredity

• Age

• Gender

Cardiometabolic Risks and Metabolic Syndrome

• Combined physical and biochemical changes increasing risk for CVD and type 2 diabetes.

• Diagnosis of metabolic syndrome requires three or more of:

  • Abdominal obesity

  • Elevated triglycerides (>150 mg/dL)

  • Low HDL cholesterol

  • Elevated blood pressure (>130/85 mmHg)

  • Elevated fasting glucose (>100 mg/dL)

Cancer

Overview and Survival

• Second leading cause of death in the U.S.

• 5-year relative survival rate has increased.

• Remission: Cancer responds to treatment and is under control.

• Cured patients show no subsequent cancer and can expect a normal life span.

How Cancer Develops

• Uncontrolled cell growth leads to a neoplasm (tumor).

• Benign tumors: Harmless, enclosed in a capsule.

• Malignant tumors: Not enclosed, can spread (metastasis), disrupt RNA/DNA, produce mutant cells.

Cancer Staging

Causes of Cancer

• Lifestyle Risks: Tobacco, alcohol, poor nutrition, inactivity, obesity, stress, inflammation, infectious agents, medical treatments, excessive sun exposure, carcinogens.

• Obesity: 18% of cases and 16% of deaths linked to excess body weight; higher BMI increases risk.

• Genetic Risks: Genetic predisposition, oncogenes (cancer-causing genes), hereditary factors.

• Reproductive/Hormonal Risks: Documented for breast and cervical cancers.

• Inflammation: Emerging evidence links inflammatory responses to cancer development.

• Occupational/Environmental Risks: Exposure to asbestos, nickel, chromate, benzene, arsenic, vinyl chloride, radiation, chemicals in foods.

• Infectious Diseases: Hepatitis B/C (liver cancer), human papillomavirus (cervical cancer), Helicobacter pylori (stomach cancer).

Types of Cancer

• Carcinomas: Most common, arise from epithelial tissues.

• Sarcomas: Originate in bones, muscles, connective tissues.

• Lymphomas: Develop in lymphatic system.

• Leukemia: Cancers of blood-forming tissues.

Prevention and Detection

• Early detection improves survival rates.

• Screening methods: self-exam, mammograms, colonoscopy, Pap tests, imaging (MRI, CT scan).

• Prevention: healthy diet, regular exercise, weight control, avoiding tobacco and excessive alcohol, sun protection.

Cancer Treatments

• Surgery

• Stereotactic radiosurgery (gamma knife)

• Chemotherapy

• Radiotherapy

• Genetic and cell mutation research

• Immunotherapy

• Cancer-fighting vaccines

• Stem cell research

Summary Table: Key Risk Factors and Prevention Strategies

Key Equations

• Blood Pressure:

• Body Mass Index (BMI):

Example

Example: A 55-year-old male with a BMI of 32, elevated blood pressure (135/88 mmHg), and high fasting glucose (110 mg/dL) meets criteria for metabolic syndrome and is at increased risk for both CVD and type 2 diabetes. Lifestyle modifications such as diet, exercise, and weight loss are recommended.

Additional info: Academic context and table entries inferred from standard health science sources and CDC guidelines.