Complications related to veno-arterial extracorporeal membrane oxygenation in patients with acute myocardial infarction: VA-ECMO complications in AMI

Development of a simple prediction model for mechanical complication in ST-segment elevation myocardial infarction patients after primary percutaneous coronary intervention

Mechanical complication (MC) is a rare but serious complication in patients with ST-segment elevation myocardial infarction (STEMI). Although several risk factors for MC have been reported, a prediction model for MC has not been established. This study aimed to develop a simple prediction model for MC after STEMI. We included 1717 patients with STEMI who underwent primary percutaneous coronary intervention (PCI). Of 1717 patients, 45 MCs occurred after primary PCI. Prespecified predictors were determined to develop a tentative prediction model for MC using multivariable regression analysis. Then, a simple prediction model for MC was generated. Age ≥ 70, Killip class ≥ 2, white blood cell ≥ 10,000/µl, and onset-to-visit time ≥ 8 h were included in a simple prediction model as "point 1" risk score, whereas initial thrombolysis in myocardial infarction (TIMI) flow grade ≤ 1 and final TIMI flow grade ≤ 2 were included as "point 2" risk score. The simple prediction model for MC showed good discrimination with the optimism-corrected area under the receiver-operating characteristic curve of 0.850 (95% CI: 0.798-0.902). The predicted probability for MC was 0-2% in patients with 0-4 points of risk score, whereas that was 6-50% in patients with 5-8 points. In conclusion, we developed a simple prediction model for MC. We may be able to predict the probability for MC by this simple prediction model.

Risk factors for lower extremity vascular complications in adult patients on veno-arterial extracorporeal membrane oxygenation

OBJECTIVE

Utilization of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has increased significantly over the last decade. Prior studies have reported worse mortality for patients with vascular complications on VA-ECMO; however, these were limited by small sample size. The purpose of this study is to investigate predictive risk factors for vascular complications in VA-ECMO patients and their potential impact on mortality.

METHODS

Patients who underwent peripheral VA-ECMO from January 2011 to December 2021 were identified. Primary outcomes were lower extremity vascular complications and in-hospital mortality. Multivariate stepwise logistic regression models were used to identify predictors of vascular complications and in-hospital mortality.

RESULTS

A total of 605 VA-ECMO patients (25% female) were identified. The mean age was 56.3 ± 13 years, and 56 (10.4%) were black. In-hospital mortality was 63.8% (n = 386), and VA-ECMO ipsilateral vascular complications occurred in 72 patients (11.9%). Vascular surgical interventions (thromboembolectomy, fasciotomies, amputation, and surgical management of cannula bleeding) were required in 30 patients (41.7%). Same-side arterial and venous cannulas, cannula size, and absence of distal perfusion cannula did not increase risk of vascular complication. Multivariate analysis identified age (odds ratio, 0.948; 95% confidence interval, 0.909-0.988; P = .0116) and pre-existing peripheral arterial disease (odds ratio, 3.489; 95% confidence inteval, 1.146-10.624; P = .0278) as independent predictors of need for vascular surgery interventions. The mortality rate of patients who developed vascular complications was not significantly different compared with the mortality rate of those who did not develop vascular complications (61% vs 64%; P = .92).

CONCLUSIONS

This study represents one of the largest series to date of lower extremity vascular outcomes in patients undergoing VA-ECMO. Our results confirm the high mortality rate associated with VA-ECMO; however, vascular complications did not represent a risk factor for mortality as previously reported. Same-sided VA-ECMO cannulas, cannula size, and the presence or absence of distal perfusion cannula did not predict vascular complications. Increasing age and presence of peripheral arterial disease are independent predictors of need for vascular surgery intervention in patients on VA-ECMO.

Veno-arterial extracorporeal membrane oxygenation for cardiogenic shock after acute myocardial infarction: Insights from a French nationwide database

BACKGROUND

We aimed to analyze the impact of timing of implantation (strategy-outcome relationship) and volume of procedures (volume-outcome relationship) on survival of veno-arterial extracorporeal membrane oxygenation (VA ECMO) for cardiogenic shock complicating acute myocardial infarction (AMI).

METHODS

We conducted an observational retrospective study through two propensity score-based analyses using a nationwide database between January 2013 and December 2019. We classified patients into early implantation (VA ECMO on the day of primary percutaneous coronary intervention [PCI]) and delayed implantation (VA ECMO beyond the day of PCI) groups. We classified patients into low- or high-volume groups based on the median hospital volume.

RESULTS

During the study period 649 VA ECMO were implanted across 20 French hospitals. Mean age was 57.1 ± 10.4 years, 80% were male. Overall, 90-day mortality was 64.3%. Patients in the early implantation group (n = 479, 73.8%) did not show a statistical difference in 90-day mortality than in the delayed group (n = 170, 26.2%) (HR: 1.18; 95% CI 0.94-1.48; p = 0.153). The mean number of VA ECMO implanted during the study period by low-volume centers was 21.3 ± 5.4 as compared to 43.6 ± 11.8 in high-volume centers. There was no significant difference in 90-day mortality between high-volume and low-volume centers (HR: 1.00; 95% CI: 0.82-1.23; p = 0.995).

CONCLUSIONS

In this real-world nationwide study, we did not find a significant association between early VA ECMO implantation as well as high-volume centers and lower mortality in AMI-related refractory cardiogenic shock.

Comparison of in-hospital outcomes of acute myocardial infarction between patients with cardiogenic shock and with cardiac arrest

In-hospital mortality of acute myocardial infarction (AMI) complicated with cardiogenic shock (CS) remains high. Also, in-hospital mortality of AMI complicated with cardiac arrest (CA) has been reported to be highest among any AMI. However, there were few reports that compared in-hospital mortality directly between AMI complicated with CS and complicated with CA. The purpose of this study was to compare in-hospital outcomes between AMI complicated with CS and complicated with CA. We retrospectively included 195 AMI patients complicated by CS or CA, and divided those into the CA group (n = 109) and the CS group (n = 86). We also subdivided the CA group into CA with persistent CS (n = 83) and CA without persistent CS (n = 26). One-third of the study population died during the index admission. In-hospital death was more frequently observed in the CA group (45.0%) than in the CS group (20.9%) (p < 0.001). In-hospital mortality was highest in the CA with persistent CS group (68.7%), followed by the CS group (20.9%), and least in the CA without persistent CS group (11.5%) (p < 0.001). Favorable neurological function was more frequently observed in the CA without persistent CS group (76.9%) and the CS group (74.4%) than in the CA with persistent CS group (27.7%) (p < 0.001). In conclusion, in-hospital mortality was higher in AMI patients with CA than in those with CS. However, when we divided AMI patients with CA into those with and without persistent CS, in-hospital mortality was lowest in CA without persistent CS, followed by CS, and highest in CA with persistent CS.

Improving Survival in Cardiogenic Shock-A Propensity Score-Matched Analysis of the Impact of an Institutional Allocation Protocol to Short-Term Mechanical Circulatory Support

Temporary mechanical circulatory support (tMCS) is a life-saving treatment option for patients in cardiogenic shock (CS), but many aspects such as patient selection, initiation threshold and optimal modality selection remain unclear. This study describes a standard operating procedure (SOP) for tMCS allocation for CS patients and presents outcome data before and after implementation. Data from 421 patients treated for CS with tMCS between 2018 and 2021 were analyzed. In 2019, we implemented a new SOP for allocating CS patients to tMCS modalities. The association between the time of SOP implementation and the 30-day and 1-year survival as well as hospital discharge was evaluated. Of the 421 patients included, 189 were treated before (pre-SOP group) and 232 after implementation of the new SOP (SOP group). Causes of CS included acute myocardial infarction (n = 80, 19.0%), acute-on-chronic heart failure in patients with dilated or chronic ischemic heart failure (n = 139, 33.0%), valvular cardiomyopathy (n = 14, 3.3%) and myocarditis (n = 5, 1.2%); 102 patients suffered from postcardiotomy CS (24.2%). The SOP group was further divided into an SOP-adherent (SOP-A) and a non-SOP-adherent group (SOP-NA). The hospital discharge rate was higher in the SOP group (41.7% vs. 29.7%), and treating patients according to the SOP was associated with an improved 30-day survival (56.9% vs. 38.9%, OR 2.21, 95% CI 1.01-4.80, p = 0.044). Patient allocation according to the presented SOP significantly improved 30-day survival.

Comparison of Long-Term Clinical Outcomes in Patients Stratified by a Novel Acute Myocardial Infarction Risk Stratification (nARS) System

BACKGROUND

As severity of acute myocardial infarction (AMI) varies widely, several risk stratifications for AMI have been reported. We have introduced a novel AMI risk stratification system linked to a rehabilitation program (novel AMI risk stratification; nARS), which stratified AMI patients into low (L)-, intermediate (I)-, and high (H)-risk groups. The purpose of this retrospective study was to compare the long-term clinical outcomes in patients with AMI among L-, I-, H-risk groups.Methods and Results: This study included 773 AMI patients, and assigned them into the L-risk group (n=332), the I-risk group (n=164), and the H-risk group (n=277). The primary endpoint was major cardiovascular events (MACE), defined as the composite of all-cause death, readmission for heart failure, non-fatal myocardial infarction, and target vessel revascularization after the discharge of index admission. The median follow-up duration was 686 days. MACE was most frequently observed in the H-risk group (39.4%), followed by the I-risk group (23.2%), and least in the L-risk group (19.9%) (P<0.001). The multivariate Cox hazard analysis revealed that the H-risk was significantly associated with MACE (HR 2.166, 95% CI 1.543-3.041, P<0.001) after controlling for multiple confounding factors.

CONCLUSIONS

H-risk according to nARS was significantly associated with long-term adverse events after hospital discharge for patients with AMI. These results support the validity of nARS as a risk marker for long-term outcomes.