Relation between energy metabolism, glycolysis, noradrenaline release and duration of ischemia

We studied the effect of 12-36 min of global ischemia followed by 36 min of reperfusion in Langendorff perfused rabbit hearts (n = 26). Metabolism was determined in terms of peak and total release of purines (adenosine, inosine, hypoxanthine), lactate and noradrenaline during reperfusion; and myocardial content of nucleotides (ATP, ADP, AMP), glycogen and noradrenaline at the end of reperfusion. An inverse relationship (r = -0.79) existed between duration of ischemia and developed pressure post-ischemia. Early during reperfusion, after 12 min of ischemia, the purine concentration (peak release) increased 100x (p < 0.01), that of lactate and noradrenaline 10x (p < 0.05). Total purine release rose with progression of the ischemic period (30x after 36 min of ischemia; p < 0.01), concomitant with a reduction in nucleotide content. Lactate release was independent from the duration of ischemia, although glycogen had declined by 30\% (p < 0.01) after 36 min of ischemia. The acid insoluble glycogen fraction, which presumably contains proglycogen, increased substantially during short-term ischemia. Peak noradrenaline increased 100x, and 200x, (p < 0.05) after 24 and 36 min of ischemia, respectively. Total noradrenaline release due to various periods of ischemia mirrored its peak release. Function recovery was inversely related to total purine and noradrenaline efflux (both r = -0.81); it correlated with tissue nucleotide content (r = 0.84). In conclusion, larger amounts of noradrenaline are released only after a substantial drop in myocardial ATP. During severe ischemia ATP consumption more than limited ATP production by anaerobic glycolysis, is a key factor affecting recovery on subsequent reperfusion. In contrast to lactate efflux, purine and noradrenaline release are useful markers of ischemic and reperfusion damage

Impact of disproportionate secondary mitral regurgitation in patients undergoing edge-to-edge percutaneous mitral valve repair

To evaluate the prognostic role of echocardiographic parameters assessing secondary mitral regurgitation (SMR) severity and left ventricular dimension, including proportionate versus disproportionate SMR, in Mitraclip recipients

Impact of COVID-2019 outbreak on prevalence, clinical presentation and outcomes of ST-elevation myocardial infarction

Aims The aim of this study was to report the prevalence, clinical features and outcomes of patients with ST-elevation myocardial infarction (STEMI) hospitalized during the Corona-Virus Disease 2019 (COVID-19) outbreak compared with those admitted in a previous equivalent period. Methods and results Eighty-five patients admitted for STEMI at a high-volume Italian centre were included. Patients hospitalized during the COVID-19 outbreak (21 February-10 April 2020) (40%) were compared with those admitted in pre-COVID-19 period (3 January-20 February 2020) (60%). A 43% reduction in STEMI admissions was observed during the COVID-19 outbreak compared with the previous period. Time from symptom onset to first medical contact (FMC) and time from FMC to primary percutaneous coronary intervention (PPCI) were longer in patients admitted during the COVID-19 period compared with before [148 (79-781) versus 130 (30-185) min; P = 0.018, and 75 (59-148)] versus 45 (30-70) min; P &lt; 0.001]. High-sensitive troponin T levels on admission were also higher. In-hospital mortality was 12% in the COVID-19 phase versus 6% in the pre-COVID-19 period. Incidence of the composite end-point, including free-wall rupture, severe left ventricular dysfunction, left ventricular aneurysm, severe mitral regurgitation and pericardial effusion, was higher during the COVID-19 than the pre-COVID-19 period (19.6 versus 41.2%; P = 0.030; odds ratio = 2.87; 95% confidence interval 1.09-7.58). Conclusion The COVID-19 pandemic had a significant impact on the STEMI care system reducing hospital admissions and prolonging revascularization time. This translated into a worse patient prognosis due to more STEMI complications