Comment
This case highlights an unusual cause for persistent post-operative
sinus tachycardia in a young patient, with only 2.8% of POTS cases
being attributed to surgery [2]. The diagnosis of POTS is based on
three factors. Firstly, a clinical syndrome characterised by symptoms of
light-headedness, blurry vision, palpitations, exercise intolerance and
fatigue. Secondly, an increase of more than 30bpm (≥ 40bpm in 12-19
years) when the person stands up from recumbent position. Thirdly,
absence of orthostatic hypotension [3, 4, 5]. The onset of POTS may
be precipitated by typical immunological stressors such as surgery,
viral infection, vaccination, trauma, pregnancy or psychological stress
[1].
Non-pharmacological treatment remains first-line and involves increasing
aerobic exercise, lower extremity strengthening, increasing salt and
fluid intake, psychological training for anxiety or pain management and
education. Pharmacological therapy is considered on an individual basis
and consists of beta-blockers to blunt orthostatic increases in heart
rate, alpha-adrenergic agents to increase peripheral vascular
resistance, mineralocorticoids to increase blood volume and serotonin
reuptake inhibitors to improve serotonin regulation [4].
There has only been one other case report in the literature reporting on
the development of POTS following thoracic surgery, involving a repair
of an aortic coarctation [6]. Similarly, they identified potential
risk factors including surgery, prolonged bed rest, and use of
antihypertensives that are known to worsen orthostatic intolerance
(amlodipine and valsartan). Additional risk factors in our case include
reduced oral intake, anaemia, autonomic insufficiency and poor sleep
[1]. Correct assessment of post-operative tachycardia including
postural telemetry is the key to identifying this condition and its
successful management.