58 yo male describes his symptomatic LBBB (left bundle branch block) to AI

Case: 58 yo male with no previous cardiac history, not taking an medications.

Pt statement: “I have a normal cardiac MRI and echo. Since COVID and the vaccine, I’ve experienced transient chest pain with LBBB, sometimes with mild shortness of breath, resolving within 30 seconds. It worsened with exercise, leading to a serious episode that sent me to the ER, where they found LAD spasm but clear arteries.

I underwent an EP study showing left bundle aberrancy with atrial overdrive pacing. Atrial fibrillation was induced and organized into atrial flutter, leading to ablation for cavotricuspid isthmus-dependent flutter. No ventricular arrhythmias were found, and my WCT was likely SVT/AT with aberration.

I improved for about a year. My cardiologist wasn’t concerned, cleared me for exercise, and ruled out cardiac remodeling. However, I still get brief LBBB episodes when standing after sitting, under stress, or in hot showers—yet sometimes not during strenuous exercise. It seems electrical, and I may have had it all my life”.

AI analysis:

Your case is really interesting, and it sounds like a mix of electrical instability and possible autonomic influences on your heart rhythm. Here’s my take on it:

1. Post-Viral & Vaccine Effects on the Heart

Since your symptoms started after COVID and the vaccine, it’s possible that they triggered some autonomic dysfunction or microvascular issues. Both COVID and the vaccine have been linked to transient heart inflammation (like myocarditis or pericarditis), which can cause electrical irritability.

2. Exercise and LBBB Episodes

• You have intermittent left bundle branch block (LBBB) with aberrancy, which suggests that under certain conditions, your conduction system temporarily slows down.
• The fact that it sometimes happens when you get up from sitting, stretch, or take a hot shower suggests autonomic involvement—your nervous system might not be regulating your heart’s conduction normally.
• The lack of LBBB during some strenuous exercise suggests it’s not purely a structural problem but more electrical instability that gets triggered inconsistently.

3. The Role of Your Ablation

• Your ablation was for cavotricuspid isthmus-dependent atrial flutter, meaning you had an extra circuit that was driving an arrhythmia.
• Your wide-complex tachycardia (WCT) episodes were likely supraventricular tachycardia (SVT) or atrial tachycardia (AT) with aberrancy rather than ventricular tachycardia, which is reassuring.
• Since your ventricular study was negative for arrhythmias, that rules out more dangerous forms of heart disease.

4. Autonomic Nervous System & Triggers

Your symptoms—triggered by standing up, stress, hot showers, and stretching—strongly suggest autonomic involvement:

• Postural changes: Could indicate a mild form of dysautonomia (like POTS or baroreceptor sensitivity).
• Hot showers & stress: Heat and stress increase vagal tone, which might momentarily affect conduction pathways.
• Exercise tolerance variability: If LBBB was due to ischemia or structural heart disease, you’d expect it to happen more consistently with exertion. The fact that sometimes you don’t get LBBB with intense exercise suggests an electrical or autonomic trigger rather than a pure blood flow issue.

5. Possible Explanations

1. Pre-existing electrical abnormality: You may have had intermittent LBBB all your life, but it only became noticeable after COVID/vaccine-related inflammation or autonomic dysfunction.
2. Residual effects from the ablation: The procedure altered conduction pathways, possibly making your heart more susceptible to aberrant conduction in certain situations.
3. Microvascular or endothelial dysfunction: Your history of LAD spasm hints at potential microvascular issues, which could affect conduction by altering local blood flow.
4. Autonomic dysfunction: This could explain why your LBBB is inconsistent and triggered by non-exercise factors like heat, stress, and posture changes.

What You Can Do

• Hydration & Electrolytes: Since autonomic instability can sometimes be worsened by dehydration or electrolyte imbalances, make sure you’re staying well-hydrated (adding vitamin C to your water was a great idea).
• Avoid known triggers: If stress or hot showers trigger LBBB, be mindful of these and experiment with lifestyle changes.
• Monitor trends: If your symptoms worsen over time or become more prolonged, a repeat EP study might be warranted.
• Exercise safely: Since your cardiologist wasn’t concerned about remodeling, you can keep exercising, but tracking symptoms might help identify patterns.

Final Thought

Your case seems to be a mix of electrical instability, autonomic dysfunction, and possibly microvascular issues. Since your MRI and echo are normal, and your cardiologist cleared you for exercise, it’s unlikely to be dangerous—but continuing to monitor and tweak your approach (hydration, stress management, and possibly autonomic testing) could help.