Читать книгу Interventional Cardiology - Группа авторов - Страница 297

When evaluating patients with definite or likely NSTE‐ACS, an early invasive strategy should be weighed against an ischemia‐guided strategy [7]. A more aggressive approach minimizes myocardial ischemia and possibly protects from a spontaneous MI, the most common complication of NSTE‐ACS [8]. However, coronary angiography and PCI also carry short‐ and long‐term risk of complications as well.

Multiple studies have compared the two treatment strategies. A meta‐analysis of randomized controlled trials along with a pooled patient level analysis from the Fast Revascularization during InStability in Coronary artery disease (FRISC‐II), Invasive versus Conservative Treatment in Unstable Coronary Syndromes (ICTUS), and Randomized Intervention Trial of unstable Angina‐3 (RITA‐3) trials demonstrated benefit with a routine invasive approach, especially in men and high risk women. This finding was primarily driven by a higher incidence of non‐fatal MI and re‐hospitalization for ACS but most of the trials did not collect data on the incidence of bleeding events [9,10]. A more contemporary study that enrolled 457 patients aged ≥80 years reported a lower incidence of myocardial infarction, need for urgent revascularization, stroke, or death (40·6% vs 61.4%; p= 0·0001) in the invasive group with no difference in minor or major bleeding events [11]. In the 15‐year follow up of the FRISC‐II trial an early invasive approach was associated with a significant delay of the next cardiovascular event [12].

According to the most recent guidelines patients with signs of ongoing ischemia (refractory or recurrent angina, hemodynamic instability, electrical alterations, etc.) should be managed with immediate revascularization (within 2 hours) [2,13]. Among stable patients, a routine invasive approach is recommended for those with high or intermediate risk features, while low risk patients should be evaluated on a case by case basis [2,13,14]. An analysis from the Targeted Platelet Inhibition to Clarify the Optimal Strategy to Medically Manage Acute Coronary Syndromes (TRILOGY‐ACS) cohort of medically managed ACS patients identified older age, diabetes mellitus, NSTEMI on presentation and lack of angiography to guide strategy, as the most important parameters associated with subsequent spontaneous myocardial infarction [15].

Optimal timing of coronary intervention in NSTE‐ACS should be tailored to the individual patient characteristics. A meta‐analysis of eight randomized controlled trials (n=5,324 patients) found no difference in mortality between an early and a delayed invasive strategy overall; however, mortality was lower with an early invasive strategy in patients with elevated cardiac biomarkers at baseline (hazard ratio [HR] 0.761, 95% CI 0·581‐0·996), diabetes (HR 0·67, 0·45‐0·99), a GRACE risk score more than 140 (HR 0·70, 0·52‐0·95), and aged 75 years older (HR 0·65, 0·46‐0·93), although tests for interaction were inconclusive [16]. The Very Early Versus Deferred Invasive Evaluation Using Computerized Tomography (VERDICT) trial showed that a strategy of very early invasive coronary evaluation (within 12 hours of diagnosis) did not improve overall long‐term clinical outcome compared with an invasive strategy conducted within 2 to 3 days in patients with NSTE‐ACS. However, in the highest risk patients, very early invasive therapy improved long‐term outcomes [17]. Criteria for determining the optimal management strategy and the timing of intervention are summarized in Figure 12.2.

Figure 12.2 Algorithm for managing NSTE‐ACS patients and determining the timing of coronary angiography and coronary revascularization.

CABG, coronary artery bypass grafting; h, hours; PCI, percutaneous coronary intervention.