A rare complication of acute pulmonary embolism is chronic thromboembolic pulmonary hypertension which is characterized by fibrothrombotic obstructions of large pulmonary arteries in conjunction with small-vessel arteriopathy. The usual treatment for this is a surgery, pulmonary endarterectomy, but in patients who cannot be operated on, they can be treated with medicine. This study compares the effects and outcomes between two groups, one including pateints who receive an operation for their chronic thromboembolic pulmonary hypertension while the other group was only treated medicinally. This is the first study to take a prospective, large-scale, international registry of newly diagnosed patients with CTEPH and include patients who are operated on and those who are not. The most significant thing about it is how that it was long-term.
It turned out that sixty percent of patients were operated on and forty percent were not operated on either by their own decision or for medical reasons. In total, 143 patients died, 51 of which were operated on and 92 that were not operated on. The significant find was the fact that patients that were operated on had a significantly better long-term survival than not-operated patients. Patients were eight years younger, had higher six minutes walking distance and higher cardiac index for those who were operated on. Survival for not-operated patients at 3 years was on seventy percent compared to eighty-nine percent for those who were operated on. One of the biggest determinants of survival was actually the presence of comorbidities such as cancer, coronary disease, left heart failure, and chronic obstructive pulmonary disease. It is important to note that medically treated patients were sicker than the other patients. Another significant note is that patients were treated off-label with endothelin receptor antagonist or phosphodiesterase-5 inhibitor. The long-term effects of the recently improved drug needs to be further evaluated to see if this could lead to more problems down the road.
While reading this it made me realize that it is very difficult to tell what a medication will do to people over a very long period of time, and it is hard to find this out before many people are already taking it. I wonder what other medications could potentially lead to major problems for patients down the road that we do not know about yet.
Delcroix M, Lang I, Pepke-Zaba J, et al. Long-term outcome of patients with chronic thromboembolic pulmonary hypertension. Circulation. 2016;133:859-71.