The predictive value of the CTOI for short-term overall mortality was previously assessed only in few prospective studies and one meta-analysis, which all showed no association between the CTOI and 30-day mortality or clinical deterioration (cardiopulmonary resuscitation, mechanical ventilation, administration of inotropic or thrombolytic agents) in the hospital [6, 14–16]. None of these studies assessed PE-related death. While our results did not show an association between CTOI and overall mortality, the CTOI was significantly associated with PE-related mortality. This is not astonishing. Given the fact that elderly patients with VTE are often multimorbid, other clinical factors may be more influential with respect to survival than the embolic burden alone [29, 30]. Despite its association with PE-related mortality, the CTOI does not appear to offer any advantage over the PESI in terms of mortality prediction.