title: Pulmonary embolectomy in high-risk acute pulmonary embolism: the effectiveness of a comprehensive therapeutic algorithm including extracorporeal life support.
abstract: OBJECTIVE
  To investigate the effectiveness of a comprehensive therapeutic algorithm including extracorporeal life support (ECLS) in high-risk acute pulmonary embolism (aPE) treated with pulmonary embolectomy.
  
  
  METHODS
  This retrospective study included 25 consecutive patients of aPE treated with pulmonary embolectomy in a single institution between June 2005 and July 2012. All patients had high-risk aPE identified by computed tomographic angiography and were not suitable for thrombolytic therapy. High-risk aPE here was defined as aPE with (1) hemodynamic instability, (2) a pulmonary artery obstruction index (PAOI)≥0.5, (3) a diameter ratio of right ventricle-to-left ventricle (RV-to-LV)≥1.0, or (4) right heart thrombi. Once the eligibility was confirmed, a 3-staged therapeutic algorithm was adopted to perform an aggressive preoperative resuscitation, an expeditious pulmonary embolectomy with multidisciplinary postoperative care, and a thorough surveillance for recurrence.
  
  
  RESULTS
  Among the 25 patients, 24 had a PAOI≥0.5 and 23 had a RV-to-LV diameter ratio≥1.0. Four patients had right heart thrombi. Sixteen patients developed preoperative instability requiring inotropic and/or mechanical support. Eight in the 16 had a preoperative cardiac arrest (CA) and six of these were bridged to surgery on ECLS. Three in the 6 patients weaned ECLS after surgery and survived to discharge. The overall in-hospital mortality was 20% (n=5). A preoperative CA (Odds ratio [OR]: 16, 95% confidence interval [CI]: 1.4-185.4, p=0.027, c-index: 0.80) and a postoperative requirement of ECLS (OR: 36, 95% CI: 2.1-501.3, p=0.008, c-index: 0.85) was the pre- and postoperative predictor of in-hospital mortality. No late deaths or re-admission for recurrence were found during a median follow-up of 19 months (interquartile range: 8-29).
  
  
  CONCLUSIONS
  Pulmonary embolectomy was an effective intervention of high-risk aPE. However, the occurrence of preoperative CA still carried a high mortality in spite of the assistance of ECLS.
authors.affiliation: Department of Cardiovascular Surgery, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Meng-Yu
authors.initials: MY
authors.lastname: Wu
authors.forename: Yuan-Chang
authors.initials: YC
authors.lastname: Liu
authors.forename: Yuan-His
authors.initials: YH
authors.lastname: Tseng
authors.forename: Yu-Sheng
authors.initials: YS
authors.lastname: Chang
authors.forename: Pyng-Jing
authors.initials: PJ
authors.lastname: Lin
authors.forename: Tzu-I
authors.initials: TI
authors.lastname: Wu
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000465:Algorithms; D002648:Child; D003131:Combined Modality Therapy; D017128:Embolectomy; D015199:Extracorporeal Membrane Oxygenation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011655:Pulmonary Embolism / Q000628:therapy*; D012189:Retrospective Studies; D018570:Risk Assessment
keywords: Acute pulmonary embolism; Cardiac arrest; Cardiogenic shock; Extracorporeal life support; Extracorporeal membrane oxygenation; Pulmonary embolectomy