What is cardiovascular disease and how is it diagnosed?

What is Cardiovascular Disease and How is it Diagnosed?

Cardiovascular disease (CVD) is a broad term encompassing atherosclerotic conditions affecting the heart and blood vessels, including coronary heart disease, cerebrovascular disease, and peripheral arterial disease, ultimately manifesting as myocardial infarction, stroke, or other vascular events. 1

Definition and Scope

CVD represents a spectrum of disorders affecting the cardiovascular system, with atherosclerosis as the underlying pathological process in most cases. 1, 2 The disease encompasses:

• Coronary artery disease (CAD) - the most common clinical manifestation, presenting as stable angina, acute myocardial infarction, unstable angina, or sudden cardiac death 1
• Cerebrovascular disease - manifesting as ischemic or hemorrhagic stroke 1
• Peripheral arterial disease - affecting limb circulation 1
• Heart failure - resulting from chronic myocardial damage 2
• Arrhythmias and conduction disorders 1

The pathophysiology centers on atherosclerotic plaque formation driven by oxidation and inflammation in arterial walls, with physical trauma and inflammation producing plaque rupture that leads to acute clinical events. 2

Diagnostic Approach: Initial Evaluation

Clinical Assessment

Begin with a thorough history focusing on chest pain characteristics, risk factor assessment, and symptom patterns. 1 Key elements include:

• Chest pain characterization: Women more often present with atypical symptoms including indigestion, dyspnea, epigastric pain, shoulder/arm/back pain, and fatigue rather than classic chest pain 1
• Risk factor identification: Smoking, hypertension, dyslipidemia, diabetes, family history of premature CAD, obesity, and sedentary lifestyle 1
• Symptom stability: Distinguish stable from unstable presentations, as unstable angina requires immediate risk stratification 1

Essential Baseline Testing

All patients with suspected CVD require a resting 12-lead ECG as the initial diagnostic test. 3 This identifies:

• ST-segment elevation myocardial infarction requiring immediate reperfusion 1
• Ischemic changes, pathological Q waves, or conduction abnormalities 1, 3
• Arrhythmias and baseline cardiac electrical activity 3

Basic biochemistry testing should include: 3

• Complete blood count
• Creatinine measurement for renal function
• Lipid profile (total cholesterol, LDL-C, HDL-C, triglycerides)
• Screening for type 2 diabetes mellitus
• High-sensitivity cardiac troponin when acute coronary syndrome is suspected 1

Structural and Functional Assessment

Resting transthoracic echocardiography is recommended to: 3

• Exclude alternative causes of symptoms
• Identify regional wall motion abnormalities suggesting ischemia or prior infarction
• Measure left ventricular ejection fraction (LVEF)
• Evaluate diastolic function

Chest X-ray is indicated for patients with: 3

• Atypical presentation
• Signs or symptoms of heart failure
• Suspicion of pulmonary disease

Risk Stratification and Advanced Diagnostic Testing

Non-Invasive Testing Selection

The choice of initial non-invasive diagnostic test should be based on clinical likelihood of CAD, patient characteristics, and local expertise. 3 Options include:

Exercise ECG testing is recommended for: 3

• Assessment of exercise tolerance and symptoms
• Evaluation of arrhythmias and blood pressure response
• Event risk stratification in selected patients

Stress imaging (nuclear perfusion or stress echocardiography) provides superior diagnostic accuracy compared to exercise ECG alone and is preferred when: 1

• Baseline ECG abnormalities preclude interpretation
• Functional assessment of ischemia burden is needed
• Risk stratification for revascularization decisions is required

Coronary CT angiography (CCTA) offers anatomic visualization but is NOT recommended when: 3

• Extensive coronary calcification is present
• Irregular heart rate exists
• Significant obesity makes good image quality unlikely

Risk Assessment Tools

Risk stratification should incorporate: 1

• Clinical parameters: Age (strongest determinant), sex, ethnicity, cardiovascular risk factors, coexisting medical conditions (diabetes, chronic kidney disease), cardiovascular comorbidities (heart failure, peripheral arterial disease), and psychosocial characteristics (depression, anxiety) 1

• Biomarkers for refined risk assessment (when clinical risk is intermediate): 1

  • High-sensitivity C-reactive protein (hsCRP) >2-3 mg/L indicates increased cardiovascular risk
  • Ankle-brachial index (ABI) ≤0.9 indicates peripheral artery disease and elevated CVD risk
  • Coronary artery calcium (CAC) score via CT (though involves radiation exposure and potential for incidental findings)

The 10-year CVD risk calculation using tools like the Pooled Cohort Equations provides a starting point for treatment discussions, though these tools lack precision and should not be used as absolute thresholds. 1

Invasive Assessment

Invasive coronary angiography (ICA) complemented by fractional flow reserve (FFR) is recommended for: 3

• Symptomatic patients with high-risk clinical profile
• Symptoms inadequately responding to medical treatment
• Patients with significant worsening of symptoms requiring expeditious evaluation 3
• Before valve surgery in patients with history of CVD, suspected myocardial ischemia, or cardiovascular risk factors 3

Diagnostic Considerations for Specific Populations

Women

Women present unique diagnostic challenges: 1

• Higher proportion of acute coronary syndrome from plaque erosion, coronary microvascular dysfunction, coronary vasospasm, or spontaneous coronary artery dissection rather than classic plaque rupture
• Less obstructive disease on angiography despite worse outcomes
• Myocardial infarction with non-obstructive coronary arteries (MINOCA) more common

Patients with Established Disease

Those with clinically manifest CVD (prior MI, stroke, or peripheral arterial disease) are at highest risk for recurrent events. 1 No distinction in risk factor management is needed between different arterial territories, though specific drug therapies may differ (e.g., beta-blockers or ACE inhibitors preferred for blood pressure control in CHD patients). 1

Common Pitfalls

• Dismissing atypical symptoms in women as non-cardiac, leading to delayed diagnosis 1
• Over-reliance on risk calculators without clinical judgment, as these tools lack precision 1
• Ordering CCTA in patients with extensive calcification or obesity, resulting in non-diagnostic studies 3
• Failing to recognize that "low-risk" individuals in high-risk populations may have higher absolute CVD risk than "high-risk" individuals in low-risk populations 1
• Not assessing patient health status and quality of life, which are independent predictors of mortality and subsequent events 1