Initial experience with a continuous mechanical aspiration system for thrombus removal before percutaneous coronary intervention.

OBJECTIVES: Here we investigate the safety and efficacy of a continuous mechanical aspiration system when used before percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS). BACKGROUND: Historically, trials of routine manual aspiration thrombectomy in ACS patients have reported mixed results. This may be due to the technical limitations of manual aspiration, which suffers from decreasing vacuum power as aspiration is performed. METHODS: This is a retrospective case series of all patients treated with continuous mechanical aspiration (Indigo CAT RX Aspiration System; Penumbra Inc.) before PCI between August 2017 and July 2020 at five centers in the United States. Data regarding angiographic assessments, procedure, and safety were examined. RESULTS: Seventy-two patients (mean age 60 ± 12.5 years, 34.7% female) with ST Elevation Myocardial Infarction (STEMI) (80.6%) or Non-ST Elevation Myocardial Infarction (NSTEMI) (19.4%) were included. Target vessels were the right coronary (43.1%), left anterior descending (33.3%), and left circumflex (23.6%). Preprocedure, 94.4% had a high thrombus burden (thrombolysis in myocardial infarction [TIMI] thrombus grade ≥ 3). Median aspiration time was 35 s and median access-to-reperfusion time was 10 min. After CAT RX alone, 86.1% had complete perfusion (TIMI flow grade 3). After the procedure, 94.4% had TIMI thrombus grade <3% and 97.2% had TIMI flow grade 3. There were no cases of ischemic stroke. Cardiovascular mortality at 30 days was 1.4%. CONCLUSIONS: In our initial experience, aspirating thrombus from ACS patients using the Indigo CAT RX Aspiration System before PCI was safe and effective for reducing thrombus burden and restoring flow.

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.

Early Utilization of Mechanical Circulatory Support in Acute Myocardial Infarction Complicated by Cardiogenic Shock: The National Cardiogenic Shock Initiative.

BACKGROUND: Acute myocardial infarction complicated by cardiogenic shock (AMI-CS) is associated with significant morbidity and mortality. Mechanical circulatory support (MCS) devices increase systemic blood pressure and end organ perfusion while reducing cardiac filling pressures. METHODS AND RESULTS: The National Cardiogenic Shock Initiative (NCT03677180) is a single-arm, multicenter study. The purpose of this study was to assess the feasibility and effectiveness of utilizing early MCS with Impella in patients presenting with AMI-CS. The primary end point was in-hospital mortality. A total of 406 patients were enrolled at 80 sites between 2016 and 2020. Average age was 64±12 years, 24% were female, 17% had a witnessed out-of-hospital cardiac arrest, 27% had in-hospital cardiac arrest, and 9% were under active cardiopulmonary resuscitation during MCS implantation. Patients presented with a mean systolic blood pressure of 77.2±19.2 mm Hg, 85% of patients were on vasopressors or inotropes, mean lactate was 4.8±3.9 mmol/L and cardiac power output was 0.67±0.29 watts. At 24 hours, mean systolic blood pressure improved to 103.9±17.8 mm Hg, lactate to 2.7±2.8 mmol/L, and cardiac power output to 1.0±1.3 watts. Procedural survival, survival to discharge, survival to 30 days, and survival to 1 year were 99%, 71%, 68%, and 53%, respectively. CONCLUSIONS: Early use of MCS in AMI-CS is feasible across varying health care settings and resulted in improvements to early hemodynamics and perfusion. Survival rates to hospital discharge were high. Given the encouraging results from our analysis, randomized clinical trials are warranted to assess the role of utilizing early MCS, using a standardized, multidisciplinary approach.

The dilated coronary sinus: utility of coronary sinus cross-sectional area and eccentricity index in differentiating right atrial pressure overload from persistent left superior vena cava.

BACKGROUND: Pulmonary hypertension and right atrial pressure overload (RAPO) cause dilation of the coronary sinus (CS). Persistent connection of the left superior vena cava (LSVC) to the CS is another cause of CS dilation. The purpose of this study was to evaluate the usefulness of coronary sinus cross-sectional area (CSA) and eccentricity index (EI) in differentiating persistent LSVC from right heart overload and RAPO in patients with dilated CS. METHODS: We identified 15 patients with a dilated CS by echocardiography. Offline analysis was used to measure CS-CSA and CS-EI at end-diastole in the parasternal long axis plane. EI was defined as B/A, where A is the widest diameter and major axis of the CS, and B is the diameter of the minor axis (perpendicular to and bisecting A at its midpoint). Persistent LSVC was confirmed by either computed tomography or injection of agitated saline in the left antecubital vein. RESULTS: CS-CSA was significantly larger in PLSVC group than in group with RAPO. Also, CS-EI was lower in PLSVC than in RAPO group (P = 0.0003). EI was the most sensitive and specific discriminator between patients with persistent LSVC vs. RAPO. CS-EI was <0.8 in all PLSVC patients and >0.8 in all RAPO patients (sensitivity and specificity = 100%). CONCLUSION: Patients with persistent LSVC have a significantly higher CS-CSA than those with elevated RA pressure. When dilated CS is present, a CS-EI <0.8 is 100% sensitive and specific for persistent LSVC. Thus, the CS-EI can be used in cases of dilated CS to diagnose the presence of persistent LSVC with a very high degree of certainty, and can help differentiate this congenital anomaly from RAPO.

Echocardiographic assessment of the accuracy of computed tomography in the diagnosis of hemodynamically significant pericardial effusions.

BACKGROUND: Although Doppler echocardiography is the noninvasive test of choice for the diagnosis of hemodynamically significant pericardial effusion (HSPE), pericardial effusion is often first detected by computed tomography (CT). Few data are available, however, regarding the accuracy of CT in the diagnosis of cardiac tamponade. METHODS: We retrospectively identified 28 consecutive hospitalized patients with pericardial effusion who underwent both chest CT and echocardiography within 48 hours between 2001 and 2005. CT images were analyzed by experienced radiologists without knowledge of the echo results. Radiologic findings were evaluated with Doppler echocardiography. RESULTS: Of the 28 patients, 15 had HSPE by echo criteria. Right ventricular wall flattening and pericardial thickening on CT correlated with HSPE with a positive predictive value of 79% and 67%, respectively. Inferior vena cava diameter by CT was not a useful predictor of HSPE. CT was most accurate in diagnosing HSPE when the effusions were large (n = 6) and was 100% sensitive and specific in this group. Of the small- to moderate-sized effusions (n = 22), the sensitivity and specificity were 80% and 75%, respectively. CONCLUSIONS: CT findings of right ventricular wall flattening, pericardial thickening, and a large pericardial effusion significantly increase the likelihood of tamponade. In this study, the majority of patients diagnosed with HSPE by CT did indeed have tamponade by standard echo criteria. Although not a useful screening tool in the diagnosis of HSPE, CT is of some help, and abnormal results warrant more urgent clinical evaluation.