Parkinson's and Heart failure

OK, so the first random topic throws us deep into the basal ganglia where a host of forgotten nuclei diligently labour over our every move....

Parkinson’s disease

Idiopathic parkinson's disease is the most common of the akinetic-rigid syndromes characterised by degeneration of the basal ganglia. Other types include multiple system atrophy (shy-drager syndrome) and progressive supranuclear palsy.

·         Incidence ↑ with age (>1% in >60s), M=F

·         Pathologically there is a loss of pigmented neurones in substantia nigra and locus caeruleus and a degeneration of the dopaminergic pathway.

·         Aetiology: Idiopathic. However, less common in smokers. Dopamine receptor antagonists (eg antipsychotics and antiemetics) can precipitate parkinsonian features.

·         Clinical triad of bradykinesia, rigidity (cogwheeling in wrists and leadpipe limbs) and tremor (resting, 4-6Hz).  This is initially asymmetrical but progressive.

·         1/3 of patients develop cognitive impairment.

·         Examination reveals expressionless face, monotonous speech, flexed posture, festinating gate, no arm swinging, rigidity, bradykinesia, tremor and micrographia.

·         Diagnosis is clinical. Consider copper studies to exclude Wilson’s disease in <50s. CT/MRI indicated if suspicion of secondary disease eg tumours / ischaemic damage.

·         Tx: Levodopa + peripheral decarboxylase inhibitors (carbidopa) to avoid peripheral dopamine side effects such as nausea, vomiting, arrhythmias.

·         Other medication includes anticholinergics, dopamine agonists, amantadine, selegiline, monoamine oxidase inhibitors and COMT (catechol – O – methyltransferase) inhibitors.

·         Progressive increase in frq of levodopa is required. Dyskinesia is an important side effect and patients may alternate between parkinsonian and dyskinetic states (“on-off” fluctuation).

·         Surgical ablation or deep brain stimulation is an option if medical therapy fails.

·         Prognosis. The disease is slowly progressive. Onset in middle age is likely to shorten lifespan. However, not likely to shorten lifespan or become severe if onset > 70.

Heart failure

Something a bit lighter now... radiological features of heart failure:

·         Cardiomegaly (cardiothoracic ratio > 50%)

·         Alveolar oedema giving ‘bat wings’ appearance

·         Bilateral pleural effusions

·         Diversion of vasculature to upper lobes

·         Kerley B lines (peripheral linear opacities)

                                                             From ultramedicine.co.uk