Thrombus aspiration for reperfusion in myocardial infarction: Predictors and clinical impact of ineffectiveness

Introduction and ObjectivesThe benefit of manual thrombus aspiration (TA) in the reperfusion of patients with ST-elevation myocardial infarction (STEMI) has been hotly debated. In most series, failure of TA has been largely unreported. Our objectives were to assess the rate, predictors, and impact on cumulative mortality of failed TA during primary percutaneous coronary intervention (PPCI).MethodsThis was a single-center, retrospective study of consecutive STEMI patients undergoing PPCI with TA. TA was considered ineffective if, before angioplasty, coronary flow was TIMI <2. Independent predictors of TA failure were assessed by logistic regression, and predictors of cumulative mortality were assessed by Cox regression analysis.ResultsOf 574 patients, TA was used in 417 (72.6%), and was effective in 365 (87.5%) and ineffective in 52 (12.5%). On multivariate analysis, SYNTAX score (OR=1.049, 95% CI: 1.015–1.084, p=0.005) and total ischemic time (OR=1.001, 95% CI: 1.000–1.003, p=0.02) were independent predictors of TA failure. Moderate or severe left ventricular dysfunction (HR=6.256, 95% CI: 1.896–20.644, p=0.003), APPROACH score (HR=1.094, 95% CI: 1.016–1.177, p=0.017), Killip class III/IV (HR=2.953, 95% CI: 1.122–7.770, p=0.028) and creatinine clearance on admission (HR=0.973, 95% CI: 0.953–0.994, p=0.011) were independently related to cumulative mortality at 24±0.82 months.ConclusionsTotal ischemic time and SYNTAX score were independent predictors of TA failure. However, in medium-term follow-up, ineffective manual TA was not independently related to cumulative mortality.

ResumoIntrodução e objetivosO benefício da trombectomia aspirativa manual (TbA) na reperfusão do enfarte de miocárdio com elevação de ST (EAMST) tem sido muito debatida. Na maioria das séries, a ineficácia da TbA tem sido pouco evidenciada. Os nossos objetivos visaram conhecer a taxa, os preditores e o impacto na mortalidade cumulativa da TbA ineficaz (TbANE) numa série de doentes submetidos a intervenção coronária percutânea primária (ICPP).MétodosEstudo retrospetivo, unicêntrico, consecutivo, de doentes com EAMST submetidos a ICPP com TbA. Considerou-se TbANE se após a TbA e antes de prosseguir a angioplastia se se obtivesse fluxo coronário TIMI<2. Identificaram-se preditores independentes de TbANE por regressão logística multivariada. Os preditores de mortalidade cumulativa foram identificados por modelo de Cox.ResultadosDentre 574 doentes, utilizou-se a TbA em 417 (72,6%), que foi eficaz em 365 (87,5%), ineficaz em 52 (12,5%). Na análise multivariada, o score SYNTAX (OR=1,049, 95% CI: 1,015-1,084, p=0,005) e o tempo isquémico total (OR=1,001, 95% CI: 1,000-1,003, p=0,02) foram os preditores independentes de TbANE. A disfunção ventricular esquerda moderada/severa (HR=6,256, 95% CI: 1,896-20,644, p=0,003), o score APPROACH (HR=1,094, 95% CI: 1,016-1,177, p=0,017), a classe 3-4 de Killip (HR=2,953, 95% CI: 1,122-7,770, p=0,028) e a clearance da creatinina na admissão (HR=0,973, 95% CI: 0,953-0,994, p=0,011), relacionaram-se de forma independente com a mortalidade cumulativa (24±0,82 meses).ConclusõesO tempo de sintomas e o score SYNTAX foram preditores independentes de TbANE. Contudo, a TbANE não teve impacto independente com a mortalidade cumulativa a médio prazo.