An otherwise healthy man would faint after a burst of heavy laughter. Investigations ruled out all medical causes!
A 58-year-old, otherwise healthy male presented to the clinic with complaints of 3 episodes of loss of consciousness over the past 2 years. Each time his syncope was preceded by a bout of extreme laughter. The patient denied any prodromal symptoms. Each time he lost consciousness for 2-3 minutes. He woke up spontaneously without any intervention. However, he would feel weak for the next 30 minutes after regaining consciousness.
The patient revealed that the second episode was 6 months after the first episode of syncope and both were elicited by heavy laughter. Between episodes, the patient remained utterly asymptomatic. Cardiologist and neurologist consultations were inconclusive.
After the third episode, the patient presented again as he was getting more anxious.
The patient’s past medical, surgical history or treatment history was unremarkable. He did not take any regular or OTC medications. He denied smoking, alcohol consumption, or recreational drug use. His family history was positive for hypertension in his mother and severe hypotension in his father. His father required medications to maintain his blood pressure.
When inquired about the previous investigations, the patient revealed that he underwent extensive investigations after the first episode including serological investigations, an echocardiogram, a nuclear stress test, Holter monitoring and a magnetic resonance imaging of the brain. All the results were normal. Moreover, he later had a tilt table test and EEG too. However, those tests also came back normal.
Physical examinations including cardiovascular and neurological examinations were normal. His vitals were also normal and there was no significant change in the blood pressure with orthostatic manoeuvres.
Therefore, after excluding the medical causes and with the history of heavy laughter, the patient received a diagnosis of laughter-induced syncope. It is a rare entity and a diagnosis of exclusion.