Aspiration Thrombectomy in Patients Undergoing Primary Angioplasty for ST Elevation Myocardial Infarction: An Updated Meta-Analysis

Aspiration thrombectomy: safe removal of thrombi too big to aspirate

Aspiration thrombectomy has been associated with an increased risk of stroke, and its routine use is not recommended. Ill-defined procedural techniques for aspiration thrombectomy may provide an explanation for inconsistent outcomes and adverse event rates in trials. Large thrombi can plug the aspiration port of the aspiration catheter and then be dislodged into the central circulation when they are retracted into the guide catheter, or when the aspiration catheter is removed from the Tuohy connector. We report a case of thrombus aspiration where a large distal thrombus was aspirated into the mouth of the aspiration catheter, held there with suction as it was removed and delivered outside the body without being dislodged. We offer several tips for safe removal of coronary thrombi too big to aspirate.

Aspiration Thrombectomy in Patients with Acute Myocardial Infarction-5-Year Analysis Based on a Large National Registry (ORPKI)

Blood flow restoration after primary percutaneous coronary intervention (pPCI) in patients with acute myocardial infarction (AMI) may not always be achieved and could be complicated by the no-reflow phenomenon (NRP). The aim of the current study was to assess the frequency of thrombus aspirations (TAs) and NRPs in patients with AMI and treated with pPCI based on the data collected during a 5-year period in the national ORPKI registry, as well as the frequency of periprocedural strokes and predictors of TA and NRP. This retrospective analysis was performed on prospectively collected data gathered in the Polish National Registry of Percutaneous Coronary Interventions (ORPKI), which covered the period between January 2014 and December 2018, and included 200,991 patients treated due to AMI out of 535,857 patients treated using PCI. Among them, 16,777 patients underwent TA. TA was mainly used in the STEMI subgroup of 14,207 patients (84.8%). The frequency of NRP among AMI patients in the thrombectomy group was 2.75% and in the non-thrombectomy group 0.82%. Predictors of TA and NRP were also assessed using multivariate analysis. The percentage of patients treated with pPCI and with PCI alone increased significantly in all of the three selected groups of patients from 88.7% to 94.3% in the AMI group (p < 0.001), from 82.3% to 90.3% in the STEMI subgroup (p < 0.001), and from 96.3% to 98.2% in the NSTEMI subgroup (p < 0.001) during the analysed period. NRP occurred more often in the thrombectomy group for the NSTEMI (0.58% vs. 3.07%, p < 0.05) and STEMI (1.06% vs. 2.69%, p < 0.05) subgroups. Periprocedural stroke occurred more often in the thrombectomy group in comparison to the non-thrombectomy group with AMI (0.03% vs. 0.01%, p < 0.05) and the NSTEMI (0.16% vs. 0.02%, p < 0.05). In conclusion, the frequency of TA has been experiencing a steady decline in recent years, regardless of AMI type, among patients treated with pPCI.

To Whom Thrombus Aspiration May Concern?

BACKGROUND

Thrombus aspiration for ST-segment elevation myocardial infarction (STEMI) may improve myocardial perfusion. However, these favourable results called into a question by data indicating not only a lack of efficacy but a risk of potentially deleterious complications.

AIM

To assess the effect of thrombus aspiration during the primary percutaneous coronary intervention (PPCI) on procedural angiographic results, stent characteristics, and major adverse cardiac and cerebrovascular events (MACCE).

METHODS

All consecutive STEMI patients candidate for PPCI and admitted to Critical Care Department, Cairo University hospitals, managed either by thrombectomy before primary PCI (if thrombus score ≥ 3) or conventional PPCI, Six hundred seven subjects were enrolled in the study divided into Group with thrombectomy before PPCI (107 subjects, 18%), and group with Conventional PCI (500 subjects, 82%). ST-segment resolution, peak CK-MB, TIMI score, thrombus score, and MBG were assessed; stent number, diameter, length and stented segment were reported and follow up MACCE was reported (in hospital and 1-year post-intervention).

RESULTS

Mean values for peak CKMB were less in thrombectomy group (228 ± 174 I/U vs 269 ± 186 I/U, p = 0.04), ST segment resolution ≥ 70% occurred in {63 subjects (58.9%) vs 233 (46.6%), p = 0.001} in thrombectomy vs conventional group respectively. TIMI score pre procedure was zero in (102 subjects (95%) vs 402 (80.4%), p = 0.001), while TIMI III post procedure was reported in (100 subjects (93.4%) vs 437 (87%), p = 0.06), MBG mean values were (2.4 ± 0.6 vs 2.0 ± 1, p = 0.001), thrombus score was higher in thrombectomy group (4.6 ± 0.4 vs 0.8 ± 1.7, p = 0.001) in thrombectomy vs conventional group respectively. Direct stenting was { 34 patients (31%) vs 102 patients (20%), p = 0.05}, mean stent diameter (2.7 ± 1.3 mm vs 3.5 ± 1.3 mm, p = 0.3), mean stent length was (19.9 mm ± 10 versus 22.7 mm ± 8 in p 0.01). mean stent number was (1.0 ± 0.5 vs 1.2 ± 0.6, p = 0.001), mean stented segment was (22.5 ± 13.5 vs 28.5 ± 15.2 mm, p = 0.001) in thrombectomy vs conventional group respectively. MACCE in hospital were reported in {9 subjects (8.4%) vs 70 (14%), p = 0.07)}. Follow up MACCE after 1 year reported in {6 subjects (5.6 %) vs 80 (16 %), p 0.= 4} in thrombectomy vs conventional group respectively.

CONCLUSION

Thrombus aspiration before primary PCI (in a selected group with thrombus score ≥ 3) improves myocardial perfusion, suggested by better ST-segment resolution, TIMI flow, less peak CKMB and MBG, associated with a higher rate of direct stenting, shorter stent length, stented segments and less number of stents. Although thrombus aspiration was done in more risky patients (higher thrombus score) MACCE (in hospital and 1 year follow up) showed no statistical difference.

Impact of Thrombus Aspiration on Mortality, Stent Thrombosis, and Stroke in Patients With ST-Segment-Elevation Myocardial Infarction: A Report From the Swedish Coronary Angiography and Angioplasty Registry

BACKGROUND

Thrombus aspiration is still being used in a substantial number of patients despite 2 large randomized clinical trials showing no favorable effect of routine thrombus aspiration during primary percutaneous coronary intervention in patients with ST-segment-elevation myocardial infarction. The aim of this observational study was to evaluate the impact of thrombus aspiration on mortality, stent thrombosis, and stroke using all available data from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR).

METHODS AND RESULTS

We identified 42 829 consecutive patients registered in SCAAR between January 2005 and September 2014 who underwent percutaneous coronary intervention for ST-segment-elevation myocardial infarction. Thrombus aspiration was used in 25% of the procedures. We used instrumental variable analysis with administrative healthcare region as the treatment-preference instrumental variable to evaluate the effect of thrombus aspiration on mortality, stent thrombosis, and stroke. Thrombus aspiration was not associated with mortality at 30 days (risk reduction: -1.2; 95% confidence interval [CI], -5.4 to 3.0; P=0.57) and 1 year (risk reduction: -2.4; 95% CI, -7.6 to 3.0; P=0.37). Thrombus aspiration was associated with a lower risk of stent thrombosis both at 30 days (risk reduction: -2.7; 95% CI, -4.1 to -1.4; P<0.001) and 1 year (risk reduction: -3.5; 95% CI, -5.3 to -1.7; P<0.001). In-hospital stroke and neurologic complications did not differ between groups (risk reduction: 0.1; 95% CI, -0.8 to 1.1; P=0.76).

CONCLUSIONS

Mortality was not different between the groups. Thrombus aspiration was associated with decreased risk of stent thrombosis. Our study provides important evidence for the external validity of previous randomized studies regarding mortality.