Background The fear of contagion during the coronavirus disease-2019 (COVID-19) pandemic may have potentially refrained patients with ST-segment elevation myocardial infarction (STEMI) from accessing the emergency system, with subsequent impact on mortality. Objectives The ISACS-STEMI COVID-19 registry aims to estimate the true impact of the COVID-19 pandemic on the treatment and outcome of patients with STEMI treated by primary percutaneous coronary intervention (PPCI), with identification of “at-risk” patient cohorts for failure to present or delays to treatment. Methods This retrospective registry was performed in European high-volume PPCI centers and assessed patients with STEMI treated with PPPCI in March/April 2019 and 2020. Main outcomes are the incidences of PPCI, delayed treatment, and in-hospital mortality. Results A total of 6,609 patients underwent PPCI in 77 centers, located in 18 countries. In 2020, during the pandemic, there was a significant reduction in PPCI as compared with 2019 (incidence rate ratio: 0.811; 95% confidence interval: 0.78 to 0.84; p < 0.0001). The heterogeneity among centers was not related to the incidence of death due to COVID-19. A significant interaction was observed for patients with arterial hypertension, who were less frequently admitted in 2020 than in 2019. Furthermore, the pandemic was associated with a significant increase in door-to-balloon and total ischemia times, which may have contributed to the higher mortality during the pandemic. Conclusions The COVID-19 pandemic had significant impact on the treatment of patients with STEMI, with a 19% reduction in PPCI procedures, especially among patients suffering from hypertension, and a longer delay to treatment, which may have contributed to the increased mortality during the pandemic. (Primary Angioplasty for STEMI During COVID-19 Pandemic [ISACS-STEMI COVID-19] Registry; NCT04412655 ).

Although incidence and prevalence of prediabetes are increasing, little is known about its cardiac effects. Therefore, our aim was to investigate the effect of prediabetes on cardiac function and to characterize parameters and pathways associated with deteriorated cardiac performance. Long-Evans rats were fed with either control or high-fat chow for 21 wk and treated with a single low dose (20 mg/kg) of streptozotocin at week 4 High-fat and streptozotocin treatment induced prediabetes as characterized by slightly elevated fasting blood glucose, impaired glucose and insulin tolerance, increased visceral adipose tissue and plasma leptin levels, as well as sensory neuropathy. In prediabetic animals, a mild diastolic dysfunction was observed, the number of myocardial lipid droplets increased, and left ventricular mass and wall thickness were elevated; however, no molecular sign of fibrosis or cardiac hypertrophy was shown. In prediabetes, production of reactive oxygen species was elevated in subsarcolemmal mitochondria. Expression of mitofusin-2 was increased, while the phosphorylation of phospholamban and expression of Bcl-2/adenovirus E1B 19-kDa protein-interacting protein 3 (BNIP3, a marker of mitophagy) decreased. However, expression of other markers of cardiac auto- and mitophagy, mitochondrial dynamics, inflammation, heat shock proteins, Ca/calmodulin-dependent protein kinase II, mammalian target of rapamycin, or apoptotic pathways were unchanged in prediabetes. This is the first comprehensive analysis of cardiac effects of prediabetes indicating that mild diastolic dysfunction and cardiac hypertrophy are multifactorial phenomena that are associated with early changes in mitophagy, cardiac lipid accumulation, and elevated oxidative stress and that prediabetes-induced oxidative stress originates from the subsarcolemmal mitochondria.

Radovits T, Oláh A, Lux Á, Németh BT, Hidi L, Birtalan E, Kellermayer D, Mátyás C, Szabó G, Merkely B. Rat model of exercise-induced cardiac hypertrophy: hemodynamic characterization using left ventricular pressure-volume analysis. Am J Physiol Heart Circ Physiol 305: H124 -H134, 2013. First published May 3, 2013 doi:10.1152/ajpheart.00108.2013.-Long-term exercise training is associated with characteristic structural and functional changes of the myocardium, termed athlete's heart. Several research groups investigated exercise training-induced left ventricular (LV) hypertrophy in animal models; however, only sporadic data exist about detailed hemodynamics. We aimed to provide functional characterization of exercise-induced cardiac hypertrophy in a rat model using the in vivo method of LV pressure-volume (P-V) analysis. After inducing LV hypertrophy by swim training, we assessed LV morphometry by echocardiography and performed LV P-V analysis using a pressureconductance microcatheter to investigate in vivo cardiac function. Echocardiography showed LV hypertrophy (LV mass index: 2.41 Ϯ 0.09 vs. 2.03 Ϯ 0.08 g/kg, P Ͻ 0.01), which was confirmed by heart weight data and histomorphometry. Invasive hemodynamic measurements showed unaltered heart rate, arterial pressure, and LV enddiastolic volume along with decreased LV end-systolic volume, thus increased stroke volume and ejection fraction (73.7 Ϯ 0.8 vs. 64.1 Ϯ 1.5%, P Ͻ 0.01) in trained versus untrained control rats. The P-V loop-derived sensitive, load-independent contractility indexes, such as slope of end-systolic P-V relationship or preload recruitable stroke work (77.0 Ϯ 6.8 vs. 54.3 Ϯ 4.8 mmHg, P ϭ 0.01) were found to be significantly increased. The observed improvement of ventriculoarterial coupling (0.37 Ϯ 0.02 vs. 0.65 Ϯ 0.08, P Ͻ 0.01), along with increased LV stroke work and mechanical efficiency, reflects improved mechanoenergetics of exercise-induced cardiac hypertrophy. Despite the significant hypertrophy, we observed unaltered LV stiffness (slope of end-diastolic P-V relationship: 0.043 Ϯ 0.007 vs. 0.040 Ϯ 0.006 mmHg/l) and improved LV active relaxation (: 10.1 Ϯ 0.6 vs. 11.9 Ϯ 0.2 ms, P Ͻ 0.01). According to our knowledge, this is the first study that provides characterization of functional changes and hemodynamic relations in exercise-induced cardiac hypertrophy.exercise-induced cardiac hypertrophy; pressure-volume analysis; systolic function; diastolic function; cardiac mechanoenergetics ATHLETE'S HEART HAS BEEN DESCRIBED as the complex structural, functional, and electrical cardiac remodeling induced by longterm exercise training (40). Exercise training-induced cardiac hypertrophy is an important physiological adaption, which includes balanced increase of left ventricular (LV) and left atrial diameters, cardiac mass, and LV wall thicknesses effected by myocyte hypertrophy and neoangiogenesis (10,12,25,36,37).Cardiac enlargement in athletes has been reported since the late 1890s (6), and several aspects of athlete's heart have been intensively inv...

function is considered to be precisely measurable only by invasive hemodynamics. We aimed to correlate strain values measured by speckle-tracking echocardiography (STE) with sensitive contractility parameters of pressure-volume (P-V) analysis in a rat model of exercise-induced left ventricular (LV) hypertrophy. LV hypertrophy was induced in rats by swim training and was compared with untrained controls. Echocardiography was performed using a 13-MHz linear transducer to obtain LV long-and short-axis recordings for STE analysis (GE EchoPAC). Global longitudinal (GLS) and circumferential strain (GCS) and longitudinal (LSr) and circumferential systolic strain rate (CSr) were measured. LV P-V analysis was performed using a pressure-conductance microcatheter, and load-independent contractility indices [slope of the end-systolic P-V relationship (ESPVR), preload recruitable stroke work (PRSW), and maximal dP/dt-enddiastolic volume relationship (dP/dtmax-EDV)] were calculated. Trained rats had increased LV mass index (trained vs. control; 2.76 Ϯ 0.07 vs. 2.14 Ϯ 0.05 g/kg, P Ͻ 0.001). P-V loop-derived contractility parameters were significantly improved in the trained group (ESPVR: 3.58 Ϯ 0.22 vs. 2.51 Ϯ 0.11 mmHg/ l; PRSW: 131 Ϯ 4 vs. 104 Ϯ 2 mmHg, P Ͻ 0.01). Strain and strain rate parameters were also supernormal in trained rats (GLS: Ϫ18.8 Ϯ 0.3 vs. Ϫ15.8 Ϯ 0.4%; LSr: Ϫ5.0 Ϯ 0.2 vs. Ϫ4.1 Ϯ 0.1 Hz; GCS: Ϫ18.9 Ϯ 0.8 vs. Ϫ14.9 Ϯ 0.6%; CSr: Ϫ4.9 Ϯ 0.2 vs. Ϫ3.8 Ϯ 0.2 Hz, P Ͻ 0.01). ESPVR correlated with GLS (r ϭ Ϫ0.71) and LSr (r ϭ Ϫ0.53) and robustly with GCS (r ϭ Ϫ0.83) and CSr (r ϭ Ϫ0.75, all P Ͻ 0.05). PRSW was strongly related to GLS (r ϭ Ϫ0.64) and LSr (r ϭ Ϫ0.71, both P Ͻ 0.01). STE can be a feasible and useful method for animal experiments. In our rat model, strain and strain rate parameters closely reflected the improvement in intrinsic contractile function induced by exercise training. speckle-tracking echocardiography; pressure-volume analysis; athlete's heart; contractility; strain LONG-TERM EXERCISE TRAINING induces physiological left ventricular (LV) hypertrophy, a molecular and cellular growth process of the heart in response to altered loading conditions (6). In contrast to pathological hypertrophy, this adaptation leads to maintained or even enhanced cardiac function (2, 14). Hemodynamic changes of exercise-induced hypertrophy were characterized by our research group in a rat model, focusing also on the improved LV inotropic state (23). Contractility is the intrinsic ability of the myocardium to generate force and to shorten independently of changes in preload or afterload with fixed heart rates. In the past few decades, efforts have been made to transfer the physiological concept of contractility to the intact beating heart (4).Pressure-volume (P-V) analysis recently became the gold standard to investigate in vivo hemodynamics in animal models. During preload reduction maneuvers such as gradual occlusion of vena cava inferior, load-independent indices of myocardial contractility could be obtained (20). Th...

Left ventricular (LV) hypertrophy is a physiological or pathological response of LV myocardium to increased cardiac load. We aimed at investigating and comparing hemodynamic alterations in well-established rat models of physiological hypertrophy (PhyH) and pathological hypertrophy (PaH) by using LV pressure-volume (P-V) analysis. PhyH and PaH were induced in rats by swim training and by abdominal aortic banding, respectively. Morphology of the heart was investigated by echocardiography. Characterization of cardiac function was completed by LV P-V analysis. In addition, histological and molecular biological measurements were performed. Echocardiography revealed myocardial hypertrophy of similar degree in both models, which was confirmed by post-mortem heart weight data. In aortic-banded rats we detected subendocardial fibrosis. Reactivation of fetal gene program could be observed only in the PaH model. PhyH was associated with increased stroke volume, whereas unaltered stroke volume was detected in PaH along with markedly elevated end-systolic pressure values. Sensitive indexes of LV contractility were increased in both models, in parallel with the degree of hypertrophy. Active relaxation was ameliorated in athlete's heart, whereas it showed marked impairment in PaH. Mechanical efficiency and ventriculo-arterial coupling were improved in PhyH, whereas they remained unchanged in PaH. Myocardial gene expression of mitochondrial regulators showed marked differences between PaH and PhyH. We provided the first comparative hemodynamic characterization of PhyH and PaH in relevant rodent models. Increased LV contractility could be observed in both types of LV hypertrophy; characteristic distinction was detected in diastolic function (active relaxation) and mechanoenergetics (mechanical efficiency), which might be explained by mitochondrial differences.