7.2a Cardiovascular Function – Diagnostic Tests

Cardiovascular Function – Diagnostic Tests

Non-Invasive Diagnostic Tools:

1. Electrocardiogram (ECG):

• Measures electrical activity of the heart.
• Keys:
  • P wave: Atrial depolarization.
  • QRS complex: Ventricular depolarization.
  • T wave: Ventricular repolarization.
• Used to monitor dysrhythmias, which can indicate conditions like myocardial infarction and hypertrophy.
• Hypertrophy Detection: Pathologic hypertrophy can alter ECG waves:
  • Right atrial hypertrophy: Changes in P wave.
  • Left atrial hypertrophy: Changes in P wave.
  • Right ventricular hypertrophy: Changes in QRS complex.
  • Left ventricular hypertrophy: Changes in QRS complex.
• Non-invasive, provides clues about heart function without surgery.

2. Holter Monitor:

• Portable ECG device worn by patients.
• Records heart activity over time, capturing intermittent arrhythmias or tachycardia during daily activities.
• Useful for diagnosing issues not present during standard ECG in a clinical setting.

3. Auscultation:

• Listening to heart sounds with a stethoscope.
• Detects valve abnormalities such as murmurs or regurgitation, and shunts (abnormal blood flow, such as with a septal defect).

4. Echocardiography:

• Uses ultrasound waves to image the heart.
• Evaluates:
  • Valve function: Are valves closing properly?
  • Wall motion: Detects wall motion abnormalities indicating damage.
  • Blood flow volumes: Assesses cardiac output and stroke volume.
  • Pericardial status: Detects fluid or inflammation in the pericardial sac.

5. Exercise Stress Test:

• Monitors heart function under physical stress (treadmill or bicycle).
• Identifies abnormalities in wall motion, valve function, or other issues that become apparent under exertion.
• Useful for diagnosing conditions not evident at rest.

Key Insights from ECG and Diagnostic Tools:

• ECG changes help detect hypertrophy and other cardiac issues without invasive procedures.
• Test results provide essential information for diagnosing and managing heart conditions, guiding further tests or treatments.

Summary:

These non-invasive diagnostic tests are essential for evaluating cardiac function, detecting abnormalities, and determining the presence of conditions such as hypertrophy or valvular disease. Monitoring tools like the ECG and Holter monitor, combined with echocardiography and stress tests, offer invaluable insight without the need for surgical intervention.