D-dimer for risk stratification in haemodynamically stable patients with acute pulmonary embolism

Abstract

Purpose: Patients with submassive pulmonary embolism (PE) have a higher short-term mortality than those with low-risk PE. Rapid identification of submassive PE is important for adequate treatment of non-massive PE. We aimed to investigate the utility of D-dimer for the prediction of submassive PE stadium in normotensive PE patients.

Patients and methods: Normotensive PE patients were classified into submassive or low-risk PE groups. In addition to the comparison of the groups, area under the curve (AUC) and D-dimer cut-off for the prediction of submassive PE stadium, multi-variate logistic regression for association between D-dimer values above this cut-off and submassive PE stadium were also calculated.

Results: The data of 129 normotensive PE patients (59.7% women, mean age 70.0 years (60.7/81.0)) were analysed retrospectively. Patients with submassive PE were older (75.0 years (61.7/81.0) vs. 66.5 years (55.7/74.2), P=0.026) and more frequently female (63.6% vs. 53.8%, P=0.35). Heart rate (100.0beats/min (85.0/108.0) vs. 80.0beats/min (70.0/96.2), P<0.0001), systolic pulmonary-artery pressure (41.55±16.79mmHg vs. 22.62±14.81mmHg, P<0.0001), and D-dimer (2.00mg/l (1.09/3.98) vs. 1.21mg/l (0.75/1.99), P=0.011) were higher in patients with submassive PE. D-dimer values >1.32mg/l were indicative of submassive PE and shock-index ≥0.7. The effectiveness (AUC) of the test was 0.63 for submassive PE and 0.64 for shock-index ≥0.7. D-dimer values >1.32mg/l were associated with submassive PE stadium (OR 3.81 (95% CI: 1.74-8.35), P=0.00083) as well as with systolic blood pressure (OR 0.98 (95% CI: 0.97-0.99), P=0.033), heart rate (OR 1.02 (95% CI: 1.00-1.04), P=0.023) and shock-index value (OR 15.89 (95% CI: 1.94-130.08), P=0.0099).

Conclusions: D-dimer values >1.32mg/l are indicative of submassive PE stadium and shock-index ≥0.7. Efficacy of D-dimer for predicting submassive PE stadium was only weak to moderate.

Keywords: D-dimer; Pulmonary embolism; Right ventricular dysfunction; Risk stratification; Tachycardia.