Sustained Mechanical Aspiration Thrombectomy for High Thrombus Burden Coronary Vessel Occlusion: The Multicenter CHEETAH Study.

BACKGROUND: Poor myocardial reperfusion due to distal embolization and microvascular obstruction after percutaneous coronary intervention is associated with increased risk of morbidity and mortality. Prior trials have not shown a clear benefit of routine manual aspiration thrombectomy. Sustained mechanical aspiration may mitigate this risk and improve outcomes. The objective of this study is to evaluate sustained mechanical aspiration thrombectomy before percutaneous coronary intervention in high thrombus burden acute coronary syndrome patients. METHODS: This prospective study evaluated the Indigo CAT RX Aspiration System (Penumbra Inc, Alameda CA) for sustained mechanical aspiration thrombectomy before percutaneous coronary intervention at 25 hospitals across the USA. Adults presenting within 12 hours of symptom onset with high thrombus burden and target lesion(s) located in a native coronary artery were eligible. The primary end point was a composite of cardiovascular death, recurrent myocardial infarction, cardiogenic shock, or new or worsening New York Heart Association class IV heart failure within 30 days. Secondary end points included Thrombolysis in Myocardial Infarction thrombus grade, Thrombolysis in Myocardial Infarction flow, myocardial blush grade, stroke, and device-related serious adverse events. RESULTS: From August 2019 through December 2020, a total of 400 patients were enrolled (mean age 60.4 years, 76.25% male). The primary composite end point rate was 3.60% (14/389 [95% CI, 2.0-6.0%]). Rate of stroke within 30 days was 0.77%. Final rates of Thrombolysis in Myocardial Infarction thrombus grade 0, Thrombolysis in Myocardial Infarction flow 3, and myocardial blush grade 3 were 99.50%, 97.50%, and 99.75%, respectively. No device-related serious adverse events occurred. CONCLUSIONS: Sustained mechanical aspiration before percutaneous coronary intervention in high thrombus burden acute coronary syndrome patients was safe and was associated with high rates of thrombus removal, flow restoration, and normal myocardial perfusion on final angiography.

Pivotal trial to evaluate the safety and efficacy of the orbital atherectomy system in treating de novo, severely calcified coronary lesions (ORBIT II).

OBJECTIVES: The ORBIT II (Evaluate the Safety and Efficacy of OAS in Treating Severely Calcified Coronary Lesions) trial evaluated the safety and efficacy of the coronary Orbital Atherectomy System (OAS) to prepare de novo, severely calcified coronary lesions for stent placement. BACKGROUND: Despite advances in interventional techniques, treatment of calcified coronary lesions remains a challenge. Stent placement in these lesions may result in stent underexpansion, malapposition, and procedural complications. METHODS: ORBIT II is a prospective, multicenter, nonblinded clinical trial that enrolled 443 consecutive patients with severely calcified coronary lesions at 49 U.S. sites from May 25, 2010, to November 26, 2012. Investigators used the centrifugal action of the OAS diamond-coated crown to modify calcified lesions prior to stent placement. RESULTS: The pre-procedure mean minimal lumen diameter of 0.5 mm increased to 2.9 mm after the procedure. The primary safety endpoint was 89.6% freedom from 30-day major adverse cardiac events compared with the performance goal of 83%. The primary efficacy endpoint (residual stenosis <50% post-stent without in-hospital major adverse cardiac events) was 88.9% compared with the performance goal of 82%. Stent delivery occurred successfully in 97.7% of cases with <50% stenosis in 98.6% of subjects. Low rates of in-hospital Q-wave myocardial infarction (0.7%), cardiac death (0.2%), and target vessel revascularization (0.7%) were reported. CONCLUSIONS: The ORBIT II coronary OAS trial met both the primary safety and efficacy endpoints by significant margins. Preparation of severely calcified plaque with the OAS not only helped facilitate stent delivery, but improved both acute and 30-day clinical outcomes compared with the outcomes of historic control subjects in this difficult-to-treat patient population. (Evaluate the Safety and Efficacy of OAS in Treating Severely Calcified Coronary Lesions [ORBIT II]; NCT01092416).

Are the results of a regional ST-elevation myocardial infarction system reproducible?

Primary percutaneous coronary intervention (PCI) is the preferred reperfusion method in patients with ST-elevation myocardial infarction (STEMI) if it can be performed in a timely manner in high-volume centers. Regional STEMI networks improve timely access to PCI but are frequently criticized for being single center. To determine if results of regional STEMI systems could be replicated and achieve similar outcomes in 2 separate geographic regions, we examined the prospective databases of 2 large regional STEMI networks that use identical standardized protocols and integrated transfer systems. The Minneapolis Heart Institute (MHI) database included 2,266 patients with STEMI from 31 hospitals (498 at the PCI hospital, 1,033 transferred from 11 hospitals <60 miles away, and 735 transferred from 19 hospitals 60 to 210 miles away). The Iowa Heart Center (IHC) database included 1,206 patients with STEMI from 24 hospitals (710 at the PCI hospital, 266 transferred from 10 hospitals <60 miles away, and 230 transferred from 13 hospitals 60 to 120 miles away). Median total door-to-balloon times for the PCI hospital, zone 1, and zone 2 patients were 64, 95, and 123 minutes for the MHI and 59, 102, and 136 for the IHC (p <0.05 for each comparison between MHI and IHC). Overall in-hospital, 30-day, and 1-year mortalities was 4.8%, 5.4%, and 8.0% respectively (p = NS for each comparison between MHI and IHC). In conclusion, the use of identical protocols in 2 large regional STEMI systems in geographically separate locations produced nearly identical outcomes, adding to evidence that regional STEMI centers expand timely access to PCI.

Effectiveness of the concomitant use of bivalirudin and drug-eluting stents (from the prospective, multicenter BivAlirudin and Drug-Eluting STents [ADEST] study).

Sirolimus-eluting stents (SESs) reduce restenosis compared with bare metal stents. Safety issues with drug-eluting stents are particularly important given concerns of possible increased thrombogenicity. Compared with heparin plus glycoprotein IIb/IIIa inhibitors, the direct thrombin inhibitor bivalirudin has been shown to reduce the risk of hemorrhagic complications in patients receiving bare metal stents, with similar efficacy in preventing ischemic complications. The safety and efficacy of percutaneous coronary intervention (PCI) with SESs and bivalirudin anticoagulation have not been prospectively studied. This prospective study performed at 9 United States hospitals evaluated 1,182 patients referred for PCI with SESs in whom the procedural anticoagulant was bivalirudin. Clopidogrel was administered before PCI in 79% of patients, and only 5.3% received procedural glycoprotein IIb/IIIa inhibitors. At 30 days, major adverse cardiac events occurred in 7.1% of patients, including 0.3% mortality, 4.4% myocardial infarction (defined as creatine kinase-MB >3x normal), 1.7% target vessel revascularization, and 0.6% stent thrombosis. Major bleeding occurred in only 0.8% of patients. Thus, use of bivalirudin as the procedural anticoagulant to support SES implantation in a "real world" population of patients undergoing PCI results in low rates of major adverse cardiac events, stent thrombosis, and major bleeding.