Letter by Dias et al Regarding Article, “Pulmonary Hypertensive Medical Therapy in Chronic Thromboembolic Pulmonary Hypertension Before Pulmonary Thromboendarterectomy”
To the Editor:
We read with great interest the recently published article by Jensen et al1 in which they presented a retrospective analysis of their robust database on the use of medical therapy before pulmonary thromboendarterectomy. Their results suggested that treatment with specific pulmonary artery hypertension drugs had minimal effect on hemodynamics before surgery and no effect on outcomes or on hemodynamics after surgery, regardless of the chosen medical treatment. We believe that despite the significant results presented, there is room for further analysis of the data that might enhance the findings of the study.
It is noteworthy that patients who received epoprostenol in pre–pulmonary thromboendarterectomy treatment had a worse hemodynamic profile than control subjects (lower cardiac output and higher right atrial pressure and total pulmonary resistance, with median total pulmonary resistance of 1380 dynes [interquartile range, 1145 to 1916 dynes] at diagnosis). Although previous studies have shown that these patients have a significantly worse prognosis after surgery,2,3 no early deaths were found in this subgroup of patients. Furthermore, they showed a significant improvement in hemodynamic profile on presurgical evaluation compared with baseline. Thus, we question whether the better outcome in terms of postoperative mortality in this group of patients was related to the hemodynamic improvement resulting from epoprostenol therapy.
The question about the use of epoprostenol as a bridge to transplantation4 or pulmonary thromboendarterectomy5 has been addressed in previous studies, but a definitive conclusion on the subject has not yet been reached. We believe that an interesting approach would be to compare the postoperative outcomes of patients who were previously treated with epoprostenol with those of patients not medically treated (control subjects) with a similar hemodynamic profile at diagnosis, aiming to isolate the effect of pre–pulmonary thromboendarterectomy epoprostenol treatment on the outcomes of these patients after surgery. Despite the small sample size of the epoprostenol-treated group, we believe that this paired comparison might allow the evaluation of preoperative treatment effects in a subgroup of patients whose hemodynamic severity could even be considered a relative contraindication for pulmonary thromboendarterectomy, serving as a basis for further trials prospectively designed to address this specific question.