Heart tests can generate some of the most complex and intimidating medical reports. From EKGs with their wavy lines and technical measurements to echocardiograms describing chamber sizes and valve function, cardiology reports often leave patients with more questions than answers.
This comprehensive guide will help you understand the most common heart tests, what the measurements mean, and when findings should concern you. Knowledge of your heart health is empowering and can help you make better decisions with your healthcare team.
What You'll Learn
- • How to interpret EKG (Electrocardiogram) results
- • Understanding echocardiogram measurements
- • Stress test results and what they indicate
- • Cardiac catheterization findings
- • Normal vs. concerning heart test values
- • Questions to ask your cardiologist
Understanding Your EKG (Electrocardiogram)
An EKG records your heart's electrical activity and is often the first heart test you'll encounter. Here's how to read the key components:
Heart Rate
Normal: 60-100 beats per minute (bpm)
Bradycardia: Less than 60 bpm
Tachycardia: More than 100 bpm
Note: Athletes often have resting heart rates below 60 bpm, which is normal for them.
Heart Rhythm
Normal Sinus Rhythm: Regular, normal pattern
Atrial Fibrillation: Irregular, rapid rhythm
Sinus Arrhythmia: Normal variation with breathing
PR Interval
Normal: 120-200 milliseconds
Short: May indicate pre-excitation
Long: May indicate heart block
QRS Duration
Normal: Less than 120 milliseconds
Wide: May indicate bundle branch block
Very wide: May suggest serious conduction problems
Common EKG Findings
"Normal Sinus Rhythm" = Good news!
"Sinus Bradycardia" = Slow but often normal
"Left Axis Deviation" = Usually not serious
"ST Elevation" = Needs immediate attention
"Atrial Fibrillation" = Requires treatment
"Non-specific changes" = Often not concerning
Decoding Your Echocardiogram (Echo)
An echocardiogram uses ultrasound to create moving pictures of your heart. Here are the key measurements:
Ejection Fraction (EF)
Normal EF
55-70%
Heart pumps efficiently
Mildly Reduced
40-54%
Slightly weakened pump
Reduced EF
<40%
Significantly weakened
Chamber Sizes
Left Ventricle (LV)
Normal dimensions:
• End-diastolic: 3.9-5.3 cm
• Wall thickness: 0.6-1.1 cm
Enlarged: May indicate high blood pressure or valve disease
Left Atrium (LA)
Normal size: 2.7-4.0 cm
Enlarged: May indicate atrial fibrillation risk or valve problems
Valve Function
Valve Descriptions
Normal/Competent: Working properly
Mild regurgitation: Small leak (common, often not serious)
Moderate regurgitation: Moderate leak
Severe regurgitation: Significant leak
Stenosis: Valve opening is narrowed
Prolapse: Valve leaflets bulge backward
Understanding Stress Test Results
Stress tests evaluate how your heart responds to increased demand. Here's what the results mean:
Normal/Negative Test
- • Heart rate increased appropriately
- • Blood pressure responded normally
- • No chest pain or shortness of breath
- • No EKG changes suggesting blockages
- • Good exercise capacity
Abnormal/Positive Test
- • EKG changes suggesting reduced blood flow
- • Chest pain or unusual shortness of breath
- • Blood pressure dropped or rose excessively
- • Irregular heart rhythms developed
- • Poor exercise tolerance
Inconclusive Results
Sometimes stress tests are "inconclusive" due to medications, inability to reach target heart rate, or baseline EKG abnormalities. Your doctor may recommend additional testing like a nuclear stress test or cardiac catheterization.
Cardiac Catheterization Results
Cardiac catheterization provides direct visualization of your coronary arteries. Here's how to understand the findings:
Coronary Artery Blockages
0-25%
Minimal disease
25-50%
Mild blockage
50-70%
Moderate blockage
>70%
Severe blockage
Blockages >70% typically require intervention (stent or bypass surgery)
Major Coronary Arteries
LAD
Left Anterior Descending - "widow maker"
RCA
Right Coronary Artery
LCX
Left Circumflex
When to Be Concerned
Urgent Findings
- • ST elevation on EKG
- • Severe coronary blockages (>70%)
- • Ejection fraction <35%
- • New irregular rhythms
- • Positive stress test with symptoms
Monitor Closely
- • Ejection fraction 40-54%
- • Moderate valve disease
- • Moderate coronary blockages (50-70%)
- • Enlarged heart chambers
- • Inconclusive stress test
Questions to Ask Your Cardiologist
About Your Results
- • What are the most important findings?
- • How do these results compare to previous tests?
- • What do these findings mean for my daily activities?
- • Are there any restrictions I should follow?
About Treatment
- • Do I need medication or procedures?
- • How often should I have follow-up tests?
- • What lifestyle changes should I make?
- • When should I call if I have symptoms?