title: Impact of transient or persistent slow flow and adjunctive distal protection on mortality in ST-segment elevation myocardial infarction.
abstract: Routine use of distal protection for ST-segment elevation myocardial infarction (STEMI) is not recommended. The purpose of this study was to analyze the impact of slow flow on mortality after STEMI, and the efficacy of adjunctive distal protection following primary thrombus aspiration. We retrospectively analyzed 414 STEMI patients who underwent primary PCI. Distal protection was used following primary thrombus aspiration only when the operator judged the patient to be at high risk of slow flow. Patients were divided into 3 groups: those receiving no thrombus aspiration (A- Group), thrombus aspiration without distal protection (A+/D- Group) or a combination of aspiration with distal protection (A+/D+ Group). Slow flow/no reflow was characterized as transient or persistent. The A-, A+/D-, and A+/D+ Groups consisted of 28.5 % (n = 118), 44.4 % (n = 184), and 27.1 % (n = 112) of patients, respectively. All-cause mortality at 180 days was 6.8 % without slow flow, 14.1 % with transient and 44.4 % with persistent slow flow (P < 0.0001), but was similar whether or not distal protection was used among these groups complicated without slow flow (A-, 8.7 %; A+/D-, 6.3 %; A+/D+, 4.3 %; P = 0.5854). However, in cases complicated with transient or persistent slow flow, distal protection reduced all-cause mortality to 38.5 % (A-), 23.3 % (A+/D-), and 10.8 % (A+/D+) at 180 days (P = 0.0114). Our data confirm that routine distal protection is not to be recommended. However, it is suggested that it could reduce mortality of patients with slow flow. Predicting slow flow accurately before PCI, however, remains a challenge.
authors.affiliation: Department of Cardiology, Tokai University School of Medicine, 143 Shimokasuya, Isehara, 259-1193, Japan.
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Fujii
authors.forename: Naoki
authors.initials: N
authors.lastname: Masuda
authors.forename: Masataka
authors.initials: M
authors.lastname: Nakano
authors.forename: Gaku
authors.initials: G
authors.lastname: Nakazawa
authors.forename: Norihiko
authors.initials: N
authors.lastname: Shinozaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsukage
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Ogata
authors.forename: Fuminobu
authors.initials: F
authors.lastname: Yoshimachi
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ikari
mesh_terms: D000368:Aged; D004562:Electrocardiography; D057505:Embolic Protection Devices; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality*; D054318:No-Reflow Phenomenon / Q000517:prevention & control*; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects; D012189:Retrospective Studies; D017131:Thrombectomy