Flow Manipulation and the Association with Myocardial Systolic Function During Extracorporeal Life Support

Background:Peripheral veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is used to support circulatory failure refractory to conventional therapy. However, data on the heart-ECMO interaction at different levels of ECMO blood flow during the immediate period after ECMO initiation are sparse. We evaluated the effects of varying ECMO blood flow rate on left ventricular systolic function.Methods:Adult patients who were supported by peripheral V-A ECMO in a tertiary referral center were recruited. Serial hemodynamic and cardiac performance parameters were measured by transthoracic echocardiogram within the first 48 hours after implementation of V-A ECMO. Measurements at 100%, 120%, and 50% of target blood flow (TBF) were compared.Results:A total of 45 patients were included, 32 (71.1%) were male, and the median age was 57 (50-64) years. The main indications for V-A ECMO were myocardial infarction 25 (55.6%) and myocarditis 6 (13.3%). With a decrease in extracorporeal blood flow from 100% to 50% of TBF, mean arterial pressure dropped from 75±18 to 67±20 mmHg (p<0.001), but stroke volume increased from 15 (8-25) to 21 (13-34) mL (p<0.001), and cardiac index increased from 0.8 (0.5-1.3) to 1.2 (0.7-1.7) L/min/m2 (p<0.001). All indices of left ventricular contractility improved at 50% compared with 100% TBF: the global longitudinal strain improved from -2.8 (-5.4-0) to -4.7 (-8.2- -1.1)% (p<0.001); left ventricular ejection fraction increased from 16.8 (10.0-28.5) to 28.2 (18.0-35.5)% (p<0.001); and left ventricular outflow tract velocity time integral increased from 4.7 (2.7-7.8) to 7.7 (3.9-11.3) cm (p<0.001). The addition of echocardiographic parameters improved the discrimination of the SAVE score in predicting hospital mortality (AUROC 0.71 vs 0.58).Conclusions:In the initial period of V-A ECMO support, left ventricular systolic function quantified bedside echocardiography was inversely related to ECMO blood flow rate. The heart-ECMO interaction should be considered when determining goals of ECMO flow after initiation.

Ejection Fraction Recovery after Coronary Artery Bypass Grafting for Ischemic Cardiomyopathy

Background Controversy exists about left ventricular systolic function recovery after coronary artery bypass grafting in patients with ischemic cardiomyopathy. The aim of this study is to evaluate the temporal evolvement of left ventricular systolic function after coronary artery bypass surgery in patients with ischemic cardiomyopathy. Patients and Methods A total of 50 patients with coronary artery disease and left ventricular ejection fraction (LVEF) ≤35% underwent isolated coronary artery bypass grafting in a single center in the period 2017 to 2019. We performed a retrospective analysis of the echocardiographic and clinical follow-up data at 3 months and 1 year postoperatively. Results Median LVEF preoperatively was 25% (20–33%), mean patient age was 66 ± 8.2 years, 33 (66%) patients were operated off-pump, and 22 (44%) procedures were non-elective. There was no in-hospital myocardial infarction, stroke, and repeat revascularization. Three (6%) patients underwent re-exploration for bleeding or tamponade. In-hospital mortality was 8% and 1-year mortality was 12%. At 1 year postoperatively, there was no repeat revascularization, no myocardial infarction, 1 (2.6%) patient had a transient ischemic attack, and 10 (20%) patients required an implantable defibrillator. There was a statistically significant median ejection fraction increase at 3 months (15% [5–22%], p < 0.0001) and 1 year (23% [13–25%], p < 0.0001) postoperatively, with an absolute increase ≥10% in 32 (74.4%) and 30 (78.9%) patients at 3 months and 1 year, respectively. Conclusion Patients with ischemic cardiomyopathy undergoing coronary artery bypass surgery show continuous recovery of left ventricular systolic function in the first postoperative year.

Campylobacter coli Myocarditis: a case report

We report the case of a 14-year-old male presented with raised myocardial injury biomarkers, on the workout, Campylobacter coli was identified on stool culture, treated with antibiotics with total resolution. Cardiac magnetic resonance showed interventricular septum and lateral wall hypokinesia and subepicardial delayed enhancement, with preserved ventricular systolic function. To our knowledge, this is the first report linking Campylobacter coli to myopericarditis in children.

The Impact of Deep Y Descent on Hemodynamics in Patients With Heart Failure and Preserved Left Ventricular Systolic Function

Background: Influence of right ventricular diastolic function on the hemodynamics of heart failure (HF). We aimed to clarify the hemodynamic features of deep Y descent in the right atrial pressure waveform in patients with HF and preserved left ventricular systolic function.Methods: In total, 114 consecutive inpatients with HF who had preserved left ventricular systolic function (left ventricular ejection fraction ≥ 50%) and right heart catheterization were retrospectively enrolled in this study. The patients were divided into two groups according to right atrial pressure waveform, and those with Y descent deeper than X descent in the right atrial pressure waveform were assigned to the deep Y descent group. We enrolled another seven patients (two men, five women; mean age, 87 ± 6) with HF and preserved ejection fraction, and implanted a pacemaker to validate the results of this study.Results: The patients with deep Y descent had a higher rate of atrial fibrillation, higher right atrial pressure and mean pulmonary arterial pressure, and lower stroke volume and cardiac index than those with normal Y descent (76 vs. 7% p &lt; 0.001, median 8 vs. 5 mmHg p = 0.001, median 24 vs. 21 mmHg p = 0.036, median 33 vs. 43 ml/m2p &lt; 0.001, median 2.2 vs. 2.7 L/m2, p &lt; 0.001). Multiple linear regression revealed a negative correlation between stroke volume index and pulmonary vascular resistance index (wood unit*m2) only in the patients with deep Y descent (estimated regression coefficient: −1.281, p = 0.022). A positive correlation was also observed between cardiac index and heart rate in this group (r = 0.321, p = 0.038). In the other seven patients, increasing the heart rate (from median 60 to 80/min, p = 0.001) significantly reduced the level of BNP (from median 419 to 335 pg/ml, p = 0.005).Conclusions: The hemodynamics of patients with HF with deep Y descent and preserved left ventricular systolic function resembled right ventricular restrictive physiology. Optimizing the heart rate may improve hemodynamics in these patients.