Thrombus aspiration before percutaneous coronary intervention (PCI) provides no additional benefit in clinical outcomes in patients with non-ST-elevation myocardial infarction (NSTEMI) compared to standard PCI, according to results from the TATORT-NSTEMI trial published in European Heart Journal: Acute Cardiovascular Care.
Holger Thiele, principal investigator, says, “TATORT-NSTEMI was the first randomised trial investigating the impact of thrombectomy prior to PCI, compared to standard PCI, in patients with NSTEMI. All previous trials had been performed in patients with ST-elevation myocardial infarction (STEMI). Tatort is a German word that translates to crime scene and is currently the title of a popular crime drama.”
“Patients needed to have a visible thrombus to be included in our study, which was not the case in the STEMI trials,” adds Thiele. “There were good reasons to believe that thrombectomy would benefit patients with NSTEMI since embolisation of thrombotic material can lead to no-reflow even after PCI is performed. Thrombus aspiration in NSTEMI is not included in guidelines because of limited data.”
TATORT-NSTEMI randomised 440 patients from eight sites in Germany in a 1:1 ratio to thrombectomy prior to PCI or standard PCI. The primary study endpoint was microvascular obstruction which was measured using cardiac magnetic resonance (CMR). As previously reported, thrombus aspiration added to PCI did not reduce microvascular obstruction compared to PCI alone in patients with NSTEMI.
The paper published today is the first report of the impact of thrombectomy prior to PCI versus standard therapy on the long-term clinical outcome of patients with NSTEMI and thrombus-containing lesions. Thiele says, “The study was not powered to assess differences in clinical outcome but we believe there were sufficient patients to detect trends, since we saw numerically lower events with aspiration thrombectomy in the short-term and most patients were still in the study at 12 months.”
The primary endpoint of the current analysis was the occurrence of major adverse cardiac events (MACE) at 12 months. MACE was defined as the composite of all-cause death, myocardial reinfarction, new congestive heart failure, and need for target vessel revascularisation. Secondary endpoints included New York Heart Association (NYHA) class and Canadian Cardiovascular Society (CCS) class, and quality of life using the standardised EuroQol5D (EQ5D) questionnaire.
The researchers found no significant difference in MACE rates at 12 months between patients with NSTEMI receiving thrombus aspiration prior to PCI compared to standard PCI alone. MACE occurred in 48 patients overall (11%). In the thrombectomy group MACE occurred in 19 patients (8.7%) compared to 29 patients (13.4%) in the standard PCI group (p=0.11). There were no significant differences between the two groups in the individual components of the primary endpoint.
Thrombus aspiration did not have any effect on functional class (as assessed by NYHA class and CCS class) or quality of life in patients with NSTEMI.
“Aspiration thrombectomy appears to provide no additional benefit on long-term clinical outcome for patients with NSTEMI who have had PCI,” says Thiele. “This is comparable to data from the TASTE and TOTAL trials in STEMI patients which found no benefit of thrombectomy on all-cause mortality and led to the procedure being downgraded in European and American guidelines.”
He continues, “This was a negative trial so it is unlikely to result in a change in the guidelines but in practice it means that clinicians will follow the STEMI recommendations. In other words, thrombus aspiration will not be used routinely in patients with NSTEMI but could be applied in bail out situations when patient have a lot of thrombus and no reflow after PCI. This is a reasonable solution.”
European Society of Cardiology (ESC) spokesperson Steen Kristensen says, “Large trials have shown that thrombus aspiration does not work in STEMI so we no longer use it routinely, but we do use it occasionally. TATORT-NSTEMI confirms that this approach can also be applied in NSTEMI. We should think twice before we use a thrombus aspiration catheter but it might be useful in selected patients.”