Adjusted mortality of extracorporeal membrane oxygenation for acute myocardial infarction patients in cardiogenic shock

Cardiogenic shock (CS) is a common cause of death following acute myocardial infarction (MI). This study aimed to evaluate the adjusted mortality of venoarterial extracorporeal membrane oxygenation (VA-ECMO) with intra-aortic balloon counterpulsation (IABP) for patients with MI-CS. We included 300 MI patients selected from a multinational registry and categorized into VA-ECMO + IABP (N = 39) and no VA-ECMO (medical management ± IABP) (N = 261) groups. Both groups' 30-day and 1-year mortality were compared using the weighted Kaplan-Meier, propensity score, and inverse probability of treatment weighting methods. Adjusted incidences of 30-day (VA-ECMO + IABP vs No VA-ECMO, 77.7% vs 50.7; P = .083) and 1-year mortality (92.3% vs 84.8%; P = .223) along with propensity-adjusted and inverse probability of treatment weighting models in 30-day (hazard ratio [HR], 1.57; 95% confidence interval [CI], 0.92-2.77; P = .346 and HR, 1.44; 95% CI, 0.42-3.17; P = .452, respectively) and 1-year mortality (HR, 1.56; 95% CI, 0.95-2.56; P = .076 and HR, 1.33; 95% CI, 0.57-3.06; P = .51, respectively) did not differ between the groups. However, better survival benefit 30 days post-ECMO could be supposed (31.6% vs 83.4%; P = .022). Therefore, patients with MI-CS treated with IABP with additional VA-ECMO and those not supported with ECMO have comparable overall 30-day and 1-year mortality risks. However, VA-ECMO-supported survivors might have better long-term clinical outcomes.

Outcomes of Venoarterial Extracorporeal Membrane Oxygenation Plus Intra-Aortic Balloon Pumping for Treatment of Acute Myocardial Infarction Complicated by Cardiogenic Shock

Background

Clinical outcomes of acute myocardial infarction complicated by cardiogenic shock remain poor with high in‐hospital mortality. Veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) has been widely used for patients with acute myocardial infarction complicated by cardiogenic shock refractory to conservative therapy, which is likely fatal without mechanical circulatory support. However, whether additional intra‐aortic balloon pumping (IABP) use during VA‐ECMO support improves clinical outcomes remains controversial. This study sought to investigate prognostic impact of the combined VA‐ECMO plus IABP treatment compared with VA‐ECMO alone.

Methods and Results

From the nationwide Japanese administrative case‐mix Diagnostic Procedure Combination (DPC), the JROAD (Japanese Registry of All Cardiac and Vascular Diseases)–DPC, we identified 3815 patients with acute myocardial infarction complicated by cardiogenic shock who underwent primary percutaneous coronary intervention and managed with VA‐ECMO. Of these, 2964 patients (77.7%) were managed with IABP (VA‐ECMO plus IABP), whereas 851 (22.3%) were managed without IABP (VA‐ECMO alone). We compared in‐hospital, 7‐day, and 30‐day mortality between the VA‐ECMO plus IABP versus the VA‐ECMO alone support. Patients managed with VA‐ECMO plus IABP demonstrated significantly lower in‐hospital, 7‐day, and 30‐day mortality than those managed with VA‐ECMO alone (adjusted odds ratios [95% CI] of 0.47 [95% CI, 0.38–0.59], 0.41 [95% CI, 0.33–0.51], and 0.30 [95% CI, 0.25–0.37], respectively). The findings were consistent in the propensity matching and inverse probability of treatment‐weighting models.

Conclusions

This large‐scale, nationwide study demonstrated that the combination of VA‐ECMO plus IABP support was associated with significantly lower mortality compared with VA‐ECMO support alone in patients presenting with acute myocardial infarction complicated by cardiogenic shock who underwent primary percutaneous coronary intervention.

Cardiopulmonary bypass and internal thoracic artery: Can roller or centrifugal pumps change vascular reactivity of the graft? The IPITA study: A randomized controlled clinical trial

Background

Cardiopulmonary bypass (CPB) induces a systemic inflammatory response (SIRS) and affects the organ vascular bed. Experimentally, the lack of pulsatility alters myogenic tone of resistance arteries and increases the parietal inflammatory response. The purpose of this study was to compare the vascular reactivity of the internal thoracic arteries (ITAs) due to the inflammatory response between patients undergoing coronary artery bypass grafting (CABG) under CPB with a roller pump or with a centrifugal pump.

Methods

Eighty elective male patients undergoing CABG were selected using one or two internal thoracic arteries under CPB with a roller pump (RP group) or centrifugal pump (CFP group). ITA samples were collected before starting CPB (Time 1) and before the last coronary anastomosis during aortic cross clamping (Time 2). The primary endpoint was the endothelium-dependent relaxation of ITAs investigated using wire-myography. The secondary endpoint was the parietal inflammatory response of arteries defined by the measurements of superoxide levels, leukocytes and lymphocytes rate and gene expression of inflammatory proteins using. Terminal complement complex activation (SC5b-9) and neutrophil activation (elastase) analysis were performed on arterial blood at the same times.

Results

Exposure time of ITAs to the pump flow was respectively 43.3 minutes in the RP group and 45.7 minutes in the CFP group. Acetylcholine-dependent relaxation was conserved in the two groups whatever the time. Gene expression of C3 and C4a in the artery wall decreased from Time 1 to Time 2. No oxidative stress was observed in the graft. There was no difference between the groups concerning the leukocytes and lymphocytes rate. SC5b-9 and elastase increased between Time 1 and Time 2.

Conclusion

Endothelium-dependent relaxation of the internal thoracic arteries was preserved during CPB whatever the type of pump used. The inflammatory response observed in the blood was not found in the graft wall within this time frame.

Trial registration

Name of trial study protocol: IPITA

Registration number (ClinicalTrials.gov): NCT04168853.

Numerical analysis of aortic hemodynamics under the support of venoarterial extracorporeal membrane oxygenation and intra-aortic balloon pump

BACKGROUND AND OBJECTIVE

A gap still exists in the hemodynamic effect of intra-aortic balloon pump (IABP), venoarterial extracorporeal membrane oxygenation (VA-ECMO), and VA-ECMO plus IABP on the blood perfusion of the coronary artery, brain, and lower limb; the relation between heart flow and ECMO flow; and the wall stress of vessels.

METHODS

A finite-element model of the aorta, ECMO, and IABP was proposed to calculate the mechanical response via fluid-structure interaction. Heart failure (HF), IABP, ECMO, and ECMO plus IABP were utilized to study the effect of support models.

RESULTS

For the pressure curve, VA-ECMO weakened the dicrotic notch of pressure compared with HF and the pulsatile index (0.494 vs. 0.706 vs. 0.471 vs. 0.613). IABP, ECMO, and ECMO plus IABP increased the perfusion of the coronary, brain, and renal artery compared with HF. However, ECMO and ECMO plus IABP clearly reduced the blood flow of the left arteria femoralis compared to that of the right arteria femoralis (ECMO: 194.04 vs. 730.80 mL/min; ECMO plus IABP: 342.15 vs. 947.22 mL/min). In addition, the flow of ECMO accessed the renal artery more than the left ventricular flow. Greater ventricular flow perfused to the renal artery at a diastolic period for ECMO plus IABP, especially at the time points of 2.192 s and 2.304 s. Compared to the velocity distribution with ECMO, the flow of the right arteria femoralis was increased in the process of IABP-on. According to these four cases, the stress of the vascular wall was increased for ECMO support at the systolic period. The peak wall stress of ECMO is increased by 20% at 1.68 s.

CONCLUSIONS

ECMO plus IABP is more conducive to the blood supply than other cases from the result of numerical simulation. The location of blood intersection was generated in the region of the renal artery, which is estimated carefully.

Body Perfusion during Adult Cardiopulmonary Bypass is Improved by Pulsatile flow with Intra-Aortic Balloon Pump

Purpose

To evaluate if the use of an intra-aortic balloon pump (IABP) during cardioplegic arrest improves body perfusion.

Methods

158 coronary artery bypass graft (CABG) patients were randomized to linear cardiopulmonary bypass (CPB) (n=71, Group A) or automatic 80 bpm intra-aortic ballon pump (IABP) induced pulsatile CPB (n=87, Group B). We evaluated hemodynamic response by Swan-Ganz catheter, inflammation by cytokines, coagulation and fibrinolysis, transaminase, bilirubin, amylase, lactate and renal function (estimated glomerular filtration rate (eGFR), creatinine, and incidence of renal insufficiency and failure).

Results

IABP induced Surplus Hemodynamic Energy was 15.8±4.9 mmHg, with higher mean arterial pressure during cross-clamping (p=0.001), and lower indexed systemic vascular resistances during cross-clamping (p=0.001) and CPB discontinuation (p=0.034). IL-2 and IL-6 were lower, while IL-10 proved higher in Group B (p<0.05). Group B showed lower chest drainage (p<0.05), transfusions (p<0.05), INR (p<0.05), and AT-III (p=0.001), together with higher platelets, aPTT (p<0.05), fibrinogen (p<0.05) and D-dimer (p<0.05). Transaminases, bilirubin, amylase, lactate were lower in Group B (p<0.05); eGFR was better in Group B from ITU-arrival to 48 hours, both in preoperative kidney disease Stages 1–2 (p<0.03) and Stage 3 (p<0.05), resulting in lower creatinine from ITU-arrival to 48 hours (p<0.03). Incidence of renal insufficiency (p=0.004) and need for renal replacement therapy (p=0.044) was lower in Group B Stage 3. Group B PaO2/FiO2 and lung compliance improved from aortic declamping to the first day (p<0.003) with shorter intubation time (p=0.01).

Conclusion

Pulsatile flow by IABP improves whole-body perfusion during CPB.

Intraaortic counterpulsation during cardiopulmonary bypass impairs distal organ perfusion

BACKGROUND

Recent studies have focused on the use of fixed-rate intraaortic balloon pumping (IABP) during cardiopulmonary bypass (CPB) to achieve pulsatile flow. Because application of an IABP catheter may represent a functional obstruction within the descending aorta, we explored the effect of IABP-pulsed CPB-perfusion with special attention to perfusion above and below the IABP balloon.

METHODS

Sixteen animals received an IABP catheter that remained turned off position (NP group, n = 8) or was switched to an automatic mode of 80 beats/min during CPB (PP group, n = 8). Flow-data and pressure-data were obtained above and below the IABP balloon. Tissue perfusion was evaluated by microspheres.

RESULTS

IABP-pulsed CPB-perfusion, as assessed at 30 minutes on CPB, increased proximal mean aortic pressure (p < 0.05) and carotid artery blood flow (p < 0.001), but decreased distal mean aortic pressure (p < 0.001). The decrease of distal mean aortic pressure in the PP group was associated with a 75 % decrease (p < 0.001) of renal tissue perfusion. During nonpulsed perfusion the respective variables remained essentially unchanged compared with pre-CPB levels.

CONCLUSIONS

Using IABP as a surrogate to achieve pulsatile perfusion during CPB contributes significantly to lowered aortic pressure in the distal portion of aorta and impaired tissue perfusion of the kidneys. The results are focusing on effects that may contribute to organ dysfunction and acute kidney injury. Consequently, assessment of perfusion pressure distal to the balloon should be addressed whenever IABP is used during CPB.

In Vivo Evaluation of Tissue Microflow under Combined Therapy with Extracorporeal Life Support and Intra-aortic Balloon Counterpulsation

Treatment with, percutaneous extracorporeal mechanical assist devices provides the ultimate therapeutic option to improve the macrocirculation in patients suffering from refractory cardiac arrest, severe cardiogenic shock or during high-risk interventions. However, the flow in the smallest vessels in these critical periods is poorly understood but prognostically of high importance. Using sidestream darkfield intravitalmicroscopy, we visualised the sublingual microflow in a patient suffering from severe cardiogenic shock supported by extracorporeal membrane oxygenation and intra-aortic balloon pump. Our results show that intra-aortic balloon counterpulsation applied in addition to extracorporeal membrane oxygenation further improves the microflow. This in vivo finding supports pilot studies favouring the application of devices supporting cardiac output (extracorporeal membrane oxygenation) together with devices aimed at pulsatility (intra-aortic balloon pump).

The impact of intraaortic balloon counterpulsation on bypass graft flow in patients with peripheral ECMO

OBJECTIVE

Numerous reports have been performed to investigate the hemodynamic effects of intraaortic balloon pumping (IABP) and nonpulsatile circulatory extracorporeal membrane oxygenation (ECMO), but studies on its impact on coronary artery bypass graft flow during concomitant use of IABP and ECMO are lacking. The aim of this study was to assess the impact of additional IABP support on the degree of blood flow increase in bypass grafts in high-risk patients with nonpulsatile femoral venoarterial ECMO.

METHODS

In six emergency coronary artery bypass graft patients (mean age = 66.3 +/- 2.1 years, gender = five males and one female, ejection fraction = 25.0 +/- 3.0%) requiring mechanical circulatory support with ECMO hemodynamic parameters and bypass graft flows were measured with and without IABP counterpulsation. A transit time flowmeter was used for intraoperative graft flow and pulsatility index (PI) measurements. Patients provided their control values.

RESULTS

The average value of the mean arterial pressure recorded prior to IABP was 63.6 + 2.9 mmHg and during IABP support 67.8 + 2.9 mmHg (p < 0.0001). IABP augmented the mean bypass graft flow from 46.8 +/- 9.6 mL/min to 56.4 +/- 12.1 mL/min (p < 0.005), resulting in a 17% increase. The difference in the PI was not statistically significant (2.6 +/- 0.2 with IABP, 2.6 +/- 0.3 without IABP).

CONCLUSIONS

We conclude that IABP-induced pulsatility significantly improves coronary bypass graft flows during nonpulsatile peripheral ECMO.