Thiamine deficiency, commonly presenting as dry and wet beriberi, a lesser-known entity in the present era, is increasingly being reported from Kashmir, a north Indian state. The present study aims to present the clinical profile of patients presenting with high-output heart failure (HOHF). Subjects with a primary diagnosis of denovo heart failure and features suggestive of HOHF were recruited; those who responded to intravenous administration of thiamine alone (responders) were adults with no co-morbidities and those who required other medications particularly diuretics (non-responders) were elderly with co-morbidities and underlying heart disease. Responders showed considerably lower mean thiamine pyrophosphate (TPP) levels and higher mean lactate and venous oxygen saturation than non-responders. More importantly, the mean drop in lactate and SVO2 following thiamine therapy was more in responders. In a setting of high risk for thiamine deficiency, features suggestive of HOHF along with elevated lactate and higher venous oxygen saturation, a response to thiamine challenge may serve as surrogate marker of thiamine deficiency.