title: Risk factors analysis of thromboembolectomy for acute thromboembolic lower extremity ischemia in native arteries.
abstract: BACKGROUND
  Aim of this study is to report the results of thromboembolectomy (ThEmb) for acute thromboembolic lower limb ischemia (ATLI) in native arteries and to create a predictive score for amputation-free survival (AFS) at 30 days.
  
  
  METHODS
  It is a single center, retrospective analysis of a four years period. All patients had ThEmb: adjunctive procedures included femoral and/or popliteal endarterectomy in 30 (18.3%) cases, PTA-stent in 24 (14.6%), and femoral endarterectomy plus PTA-stent in 12 (7.3%). Fasciotomies were performed in 6 (3.6%) patients. Predictors of AFS identified on univariate screen (inclusion threshold, P<.20) were included in a multivariable model. The resulting significant predictors were assigned an integer score to stratify patients into risk groups.
  
  
  RESULTS
  Authors analyzed 164 limbs in 164 patients. Mean age was 80±10 years (range, 40-99). In-hospital mortality was 9.8% (N.=16); AFS at 30 days was 84.7% (N.=139). The anatomic level (iliac vs. femoropopliteal vs. infrapopliteal) of the occlusion did not affect AFS (P=.326). Multivariable analysis identified six significant predictors of AFS at 30 days: age >85 (P=0.050), chronic obstructive pulmonary disease (P=0.008), chronic renal insufficiency (P=0.019), late (>6 hours) onset (P=0.004), the presence of major neurologic deficit (P=0.023), and an increased (>800IU/L) level of creatine phosphokinase (P=0.001). An integer score generated two risk groups (low-risk 0-2 [70.1% of cohort], and high-risk ≥3 [29.9% of cohort]): stratification of the patients according to risk category yielded significantly different AFS at 30 days (low-risk 5.2% vs. high-risk 38.8%, P<0.0001).
  
  
  CONCLUSIONS
  Among patients selected to undergo ThEmb for ATLI in native arteries, this risk score identified a group of patients with a 40% chance of death or major amputation at 30 days. The score can help to optimize the operative strategy, but further prospective validation is needed.
authors.affiliation: Division of Vascular Surgery, Department of Surgery and Morphological Sciences, University of Insubria School of Medicine, Circolo University Hospital, Varese, Italy - gabriele.piffaretti@uninsubria.it.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Piffaretti
authors.affiliation: Division of Vascular Surgery, Department of Surgery and Morphological Sciences, University of Insubria School of Medicine, Circolo University Hospital, Varese, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Angrisano
authors.affiliation: Division of Vascular Surgery, Department of Surgery and Morphological Sciences, University of Insubria School of Medicine, Circolo University Hospital, Varese, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Franchin
authors.affiliation: Division of Vascular Surgery, Department of Surgery and Morphological Sciences, University of Insubria School of Medicine, Circolo University Hospital, Varese, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Ferrario
authors.affiliation: Division of Vascular Surgery, Department of Surgery and Morphological Sciences, University of Insubria School of Medicine, Circolo University Hospital, Varese, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Rivolta
authors.affiliation: Unit of Anesthesia and Palliative Care, Circolo University Hospital, Varese, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Bacuzzi
authors.affiliation: Division of Vascular Surgery, Department of Surgery and Morphological Sciences, University of Insubria School of Medicine, Circolo University Hospital, Varese, Italy.
authors.forename: Patrizio
authors.initials: P
authors.lastname: Castelli
authors.affiliation: Division of Vascular Surgery, Department of Surgery and Morphological Sciences, University of Insubria School of Medicine, Circolo University Hospital, Varese, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Tozzi
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000671:Amputation, Surgical; D000066491:Clinical Decision-Making; D017128:Embolectomy / Q000009:adverse effects* / Q000401:mortality; D005260:Female; D006801:Humans; D007511:Ischemia / Q000000981:diagnostic imaging / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D007558:Italy; D023821:Limb Salvage; D035002:Lower Extremity / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D058729:Peripheral Arterial Disease / Q000000981:diagnostic imaging / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013923:Thromboembolism / Q000000981:diagnostic imaging / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome