A Post Shift Potpourri: Levocardia, Fascicular VT, Multiple System Atrophy

Some random stuff from last shift:

Question: ​ The radiologist noted levocardia. What does that even mean?

• The radiologist mentioned levocardia in the CT impression of a patient’s that we had a really hard time getting POCUS echo windows

• As you would expect, this means “left sided”, which seems normal. In this guy, it was attributed to a theorized congenital loss of the pericardium. His heart was rotated and shifted to the left side of his chest. Does his disease matter clinically? Probably not?

• On the other hand, “Isolated Levocardia” is an actual disease… where you have situs inversus of the abdominal viscera, but the heart in a normal anatomic position. This is in comparison to dextrocardia, where all of the organs are inverted.  This usually is associated with fairly complex cardiac defects and a poor prognosis.

Question: What is Belhassan’s VT (fascicular VT)? 

• Belhassan’s VT is the most common idiopathic VT of the LV.

• Idiopathic VT basically just means it’s VT that isn’t associated with structural heart disease.

• It is a re-entrant tachycardia seen in young healthy adults WITHOUT structural heart disease.

• Attacks are associated with sympathetic overload (exercise, infection, excitement, sympathomimetics).

• It is due to an ectopic focus in the LV—and can look slightly different depending on where the re-entry circuit is located (vast majority in the posterior fascicle).

• Can be commonly confused for SVT with RBBB

• Some EKG Findings that could suggest this form of VT

  • RBBB morphology with a left axis deviation

  • Dissociated P-waves  (AV dissociation) and a narrow-complex capture beats

  • Most notably, this is verapamil sensitive, and usually resistant to adenosine and lidocaine

Question: What is Multiple System Atrophy?

Very hard to summarize succinctly. I recommend reviewing the UptoDate on it.

What is it?

• Neurodegenerative disorder that encompasses autonomic, pyramidal, Parkinsonian, and cerebellar features—in the same class as Parkinson Disease and Lewy Body Dementia.  Alpha-synuclein aggregation is the shared pathophysiology!

Clinical Features

• Younger age of onset, usually in the 50s.

• Prodromal symptoms that last years—that include REM sleep behavior disorder, autonomic dysfunction (like urinary incontinence), and subtle motor signs, often mild parkinsonian signs.

• The two main subtypes are MSA with predominant parkinsonism or MSA with predominant cerebellar ataxia.

• Parkinsonism: characterized by akinesia, rigidity, postural instability, and a jerky postural tremor.

• Both subtypes will often have speech/swallowing dysfunction and postural abnormalities (such as antecollis, which is where the head and neck bend forward significantly).

Diagnosis

• Clinical + a levodopa response assessment. Parkinson Disease will see a good response…MSA will not.

The prognosis of MSA is unfortunately grim.

Cheers!

Dillon