Discussion
Our experience highlights the reliability of radical thrombectomy in
massive PE cases. Thrombectomy for peripheral PE remains a challenge.
Thrombectomy in acute PE surgery has often been performed in beating
hearts, as we have previously reported4. The concern
regarding beating surgery for PE cases is the possibility of residual
peripheral PA thrombi. The advantages of pulmonary embolectomy are
reduction of PA pressure immediately after surgery5and improvement of right ventricular function after
surgery6, which requires more reliable thrombus
removal. Some researchers have recommended gentle thrombectomy with a
Fogarty catheter if the thrombus is torn off during thrombectomy to
avoid PA injury and the associated pulmonary
hemorrhage7. However, this approach for peripheral PE
is imperfect and can lead to right ventricular failure and/or chronic
thromboembolic pulmonary hypertension (CTEPH)8. To
address this concern, we recently applied the CTEPH technique to treat
acute PE. CTEPH surgery aims to reduce postoperative right ventricular
pressure by involving a secure endarterectomy of the peripheral PA under
circulatory arrest9,10. Obtaining a clear view of the
right PA is also challenging in acute PE surgery; mobilizing the SVC and
compressing the aorta, as described above, can facilitate the task.
Furthermore, the right thrombus of the right PA is more prone to tearing
than the left PA, owing to anatomical angulation issues. Even if the
thrombus breaks off, as explained above, the present method allows for
the removal of the thrombus from the peripheral PA. The difference with
surgery for CTEPH is that the present procedure does not require
circulatory arrest as a fresh thrombus is not strongly adherent to the
PA wall. We believe that the cardiac arrest procedure does not adversely
affect postoperative cardiac function. All patients without preoperative
ECMO support were successfully weaned off CPB. Although one preoperative
ECMO case was lost, both preoperative ECMO cases were successfully
weaned from ECMO postoperatively. The postoperative course and computed
tomography findings indicated that our procedure could accomplish
radical thrombectomy of peripheral PE, resulting in low right
ventricular pressure and stable hemodynamics postoperatively. Several
studies have compared surgical and nonsurgical
approaches5,11, but few have compared the clinical
outcomes of each surgical approach. We believe that our technique can be
useful for treating severe PE, and more experience should be
accumulated.
Author contributions: Concept/design: HS, RK, MM. Article
drafting: HS. Critical revision of the article: RK. Approval of the
article: all authors.