Author Correction: Aortic acceleration as a noninvasive index of left ventricular contractility in the mouse

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

COMPARISON OF LEFT VENTRICULAR CONTRACTILITY IN SILENT MYOCARDIAL ISCHEMIA BY ECHOCARDIOGRAPHY AND PERFUSION SCINTIGRAPHY

The aim of the study was to compare the methods of echocardiography and single-photon emission computed tomography in assessing local left ventricular contractility in silent myocardial ischemia; to consider the possibility of comparing the data of echocardiography and single-photon emission computed tomography of myocardium in such patients.

Flow manipulation and the association with myocardial contractility during extracorporeal life support (FLAME)

Funding Acknowledgements Type of funding sources: None. Background Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is an advanced technique in extracorporeal life support (ECLS) used to support extreme circulatory failure including patients with cardiac arrest and cardiogenic shock refractory to conventional support. It is a long-standing belief that peripheral V-A ECMO poses increased afterload to the inured heart, but conventional echocardiographic measurements are often insensitive in detecting subtle changes in loading conditions. Purpose This study aimed to evaluate the effects of varying blood flow during peripheral V-A ECMO on intrinsic myocardial contractility, using detailed echocardiographic assessment including speckle tracking echocardiography (STE). Methods Adult patients with acute cardiogenic shock who were supported by peripheral V-A ECMO from April 2019 to September 2020 were recruited. Serial hemodynamic and cardiac performance parameters were measured by transthoracic echocardiogram (TTE) within 48 hours after implementation of V-A ECMO, at different levels of extracorporeal blood flow – 100%, 120% and 50% of target blood flow (TBF). Results A total of 30 patients were included. 22 (71%) were male, and the mean (SD) age was 54 (13) years. The major indications for V-A ECMO were myocardial infarction (19, 63% patients), and myocarditis (5, 17%). With a decrease in extracorporeal blood flow from 100% to 50% of TBF, mean arterial pressure (MAP) dropped from 76+/-3 to 64+/-3mmHg (p <0.001), and cardiac index (CI) increased from 0.89+/-0.13 to 1.27+/-0.18L/min/m2 (p < 0.001). All indices of left ventricular contractility improved at a lower extracorporeal blood flow: the myocardial contractility measured by global longitudinal peak systolic strain (GLPSS) improved from -3+/-0.7% to -5+/-0.8% (p < 0.001); left ventricular ejection fraction (LVEF) increased from 21.5+/-2.6% to 30.9+/-2.7% (p < 0.001) and 19.7+/-3.1% to 28.4+/-3.2% (p < 0.001) by biplane and linear methods, respectively; left ventricular index of myocardial performance (LIMP) improved from 1.51+/-0.12 to 1.03+/-0.09 (p < 0.001). Similar findings were reproduced when comparing left ventricular contractility at extracorporeal blood flows of 120% and 50% of TBF. Conclusions The ECMO blood flow rate in peripheral V-A ECMO is inversely related to myocardial contractility, and is quantifiable by myocardial strain measured by STE.

The case of recurrent tako­tsubo syndrome on the background of coronary atherosclerosis

Takotsubo syndrome (TS) is characterized with a reversible disorder of left ventricular contractility. At present time, it is established that various factors, both psycho-emotional and clinical, can trigger this disease. Notably, according to current opinions, coronary atherosclerosis may accompany TS and not be its exclusion criteria as it was previously thought. This article presents a clinical case of TS relapse in a female patient aged 83 years at 5 years following the first episode associated with progression of coronary atherosclerosis.

Post-extrasystolic potentiation differentiates “true” from “pseudo” Low-flow, Low-gradient aortic stenosis

Post-extrasystolic potentiation (PESP) is a marker of contractile reserve and refers to the augmentation of left ventricular contractility due to preload recruitment and rise in intracellular calcium following a premature beat. In this case report we show that PESP might be a safe and helpful aid to evaluate low flow, low gradient aortic stenosis and contractile reserve in the cathlab, thereby reducing the potential risk of complications associated with intravenous dobutamine evaluation and reducing unnecessary testing.