Subclavian artery stenting: factors influencing long-term outcome

This study provides extended follow-up of a nonrandomized series of symptomatic patients who underwent subclavian stent-supported angioplasty (SSA) with emphasis on preprocedure factors that may have influenced outcome. The endpoints of mortality and restenosis were analyzed using backward stepwise logistic regression with the following clinical variables: coronary artery disease, hypertension, hyperlipidemia, smoking, diabetes mellitus, chronic obstructive pulmonary disease, chronic renal insufficiency/failure, and hypothyroidism. Restenosis is reported based on prospective serial noninvasive studies and/or angiography. Mortality was evaluated by retrospective database review and inquiry to the State Department of Health and Human Services' statistical registry in patients who were lost to follow-up. Over a 9-year period (mean follow-up, 36.1 +/- 30.4 months; maximum observation, 109.5 months), 101 stents were placed in 91 consecutive patients (37 male, 54 female). The mean age at intervention was 62.03 +/- 9.3. The procedure was technically successful in 89 patients 97% (mean pre- and postoperative stenosis and pressure gradients were 90.2% +/- 9.4% vs. 3.7% +/- 6.6%, P < 0.001, and 59.9 +/- 35.2 vs. 0 mm Hg, P < 0.001, respectively), with 13 minor complications and no immediate major complications. One patient died of unrelated causes within 30 days. Per Kaplan-Meier method, for years 1 through 5, the rates of overall patency were 96%, 91%, 86%, 77%, and 72%; likewise, overall patient survival was 93%, 88%, 8%4, 81%, and 76%. No clear predictors for restenosis were discovered, although a trend toward higher recurrence was noted in women (18.5% in female vs. and 8.6% in male; P > 0.05), but the same were less likely to die during follow-up (P > 0.001). Also, the presence of hypothyroidism (P = 0.004) and increasing age (P = 0.068) were positively correlated with all-cause mortality. This study suggests that SSA is predictable, safe, and durable. The diagnosis of symptomatic subclavian disease is of prognostic importance, with age and male gender representing important predictors of all-cause long-term mortality. The strong association of increased mortality with hypothyroidism is difficult to discard and raises the question of a yet to be described thyroid steal phenomena.