Coronavirus disease 2019 (Covid-19) is associated with high incidence of venous and arterial thromboembolic events. Currently, there are no markers to guide antithrombotic therapy in Covid-19. Immature platelets represent a population of hyper-reactive platelets associated with arterial events. This prospective study compared consecutive Covid-19 patients (n = 47, median age = 56 years) to patients with acute myocardial infarction (AMI, n = 100, median age = 59 years) and a group of stable patients with cardiovascular risk factors (n = 64, median age = 68 years). Immature platelet fraction (IPF) and immature platelet count (IPC) were determined by the Sysmex XN-3000 auto-analyzer on admission and at subsequent time-points. IPF% on admission was higher in Covid-19 than the stable group and similar to the AMI group (4.8% [IQR 3.4-6.9], 3.5% [2.7-5.1], 4.55% [3.0-6.75], respectively, p = 0.0053). IPC on admission was also higher in Covid-19 than the stable group and similar to the

Background Immature platelets in the circulation can be measured as immature platelet fraction (IPF). Limited data exist regarding IPF during the course of an acute myocardial infarction (AMI), the association between IPF and extent of cardiac damage, and the long‐term prognostic implications of IPF in patients with AMI. Aims To examine the temporal course of IPF during the first month after AMI, the association between IPF and extent of cardiac damage, and the long‐term prognostic effect of IPF in AMI patients. Methods Patients with AMI treated with percutaneous coronary intervention (PCI) were examined. IPF was evaluated by a Sysmex XN‐3000 autoanalyzer, at 4 time points: baseline; one day post‐PCI; 3 days post‐PCI, and 30 days post‐PCI. The association between peak troponin‐T levels and IPF was evaluated. One‐year clinical outcomes (cardiac hospitalization, urgent revascularization, or death) were assessed. Results One hundred patients were included, mean age was 59.5 ± 11.3 years, 82 were men, 27 had diabetes, and 54 were hospitalized with ST‐segment elevation myocardial infarction (STEMI) and 46 with non‐ST segment elevation myocardial infarction (NSTEMI). The levels of IPF modestly decreased a day after PCI but did not change in subsequent measurements. Peak troponin‐T level was significantly associated with the levels of IPF at all 4 time points. IPF levels three days post‐PCI were associated with the composite clinical outcome at 1 year. Conclusions The levels of IPF following AMI remain relatively stable over a one‐month period. Higher levels of IPF during the acute phase of AMI appear to be associated with worse cardiac outcomes at 1 year.

Our aim was to investigate trends in prognosis among survivors of acute coronary syndrome according to left ventricular ejection fraction during a 16-year period. Methods: Data were derived from the Acute Coronary Syndrome Israeli Survey during the years 2000-2016. Patients aged 18 years and older were included in the analysis (N = 11,725). Patients were classified into two groups based on their left ventricular ejection fraction: preserved (!50%) and reduced (<50%) and also according to their acute coronary syndrome onset (2000-2006 early period vs. 2008-2016 late period). Endpoints were all-cause mortality rates at one and three years after the index event.Results: Preserved left ventricular ejection fraction was present in 5047/11,725 (43%) of patients. As expected, patients with preserved left ventricular ejection fraction had lower 1 and 3-year mortality rates as compared with reduced left ventricular ejection fraction regardless of the acute coronary syndrome period onset (6% vs. 19%, p < 0.001). Nevertheless, in the late period the prevalence of reduced left ventricular ejection fraction decreased significantly, becoming equal to preserved left ventricular ejection fraction [2761 (50.5%) vs. 2713 (49.5%) respectively, p = 0.3]. Moreover, prognosis during the late period as compared with the early period was improved only in patients with reduced left ventricular ejection fraction (HR 0.79; 95% CI 0.70-0.89, p = 0.0001). Conclusion:The prevalence of reduced left ventricular ejection fraction has decreased and prognosis has improved during the past several years but is still much worse than the prognosis of preserved left ventricular ejection fraction.

Introduction Cannabis use is known to be associated with significant cardiovascular morbidity. We describe three cases of cannabis-related malignant arrhythmias, who presented to the cardiac department at our institution within the last 2 years. All three patients were known to smoke cannabis on daily basis. Case summaries Case 1: A 30-year-old male, presented with recent onset of palpitations. A 12-lead electrocardiogram (ECG), transthoracic echocardiogram (TTE), and blood tests were all normal. During an inpatient exercise treadmill test (ETT) he developed polymorphic ventricular tachycardia (VT), which converted spontaneously to supraventricular tachycardia (SVT) in the recovery phase of the test. Subsequent risk stratification with cardiac magnetic resonance imaging and coronary angiography showed no abnormalities and an electrophysiological study was negative for sustained VT, however, SVT was easily induced with rapid conversion to atrial fibrillation. The patient successfully stopped smoking all tobacco products including cannabis and was treated with beta-blockers, with no further episodes of arrhythmia. Case 2: A 30-year-old male presented to the Emergency Department with palpitations, chest pain, and dizziness that improved during exertion. His initial ECG demonstrated complete atrioventricular block (AVB). Subsequent traces showed Mobitz Type I and second-degree AVB, which converted to atrial flutter after exertion. Routine blood tests, TTE, and an ETT were all normal and he was discharged home with no conduction abnormalities. Case 3: A 24-year-old male presented with two episodes of syncope. Baseline examination was normal, with an ECG showing a low atrial rhythm. Interrogation of his implantable loop recorder showed episodes of early morning bradycardia episodes with no associated symptoms. Discussion Cannabis-related arrhythmia can be multiform regarding their presentation. Therefore, ambiguous combinations of arrhythmia should raise suspicion of underlying cannabis abuse, where clinically appropriate. Although causality with regards to cannabis use cannot be proven definitively in these cases, the temporal relationship between drug use and the onset of symptoms suggests a strong association.

Coronavirus disease 2019 (Covid-19) is associated with a high incidence of venous and arterial thromboembolic events. Currently, there are no clinical or laboratory markers that predict thrombotic risk. Circulating immature platelets are hyper-reactive platelets, which are associated with arterial thrombotic events. The aim of this study was to assess whether the proportion of circulating immature platelets is associated with disease severity in Covid-19 patients. Patients admitted with Covid-19 disease were prospectively assessed. Immature platelet count (IPC) and immature platelet fraction (IPF) were measured at admission and at additional time points during the hospital course using the Sysmex XN-3000 auto-analyzer. A total of 136 consecutive patients with Covid-19 were recruited [mean age 60 ± 19 years, 49% woman, 56 (41%) had mild-moderate disease and 80 (59%) had severe disease at presentation]. The median IPF% was higher in patients with severe compared to mild-moderate disease [5.8 (3.9–8.7) vs. 4.2 (2.73–6.45), respectively, p = 0.01]. The maximal IPC value was also higher in patients with severe disease [15 (10.03–21.56), vs 10.9 (IQR 6.79–15.62), respectively, p = 0.001]. Increased IPC was associated with increased length of hospital stay. Patients with severe Covid-19 have higher levels of IPF than patients with mild-moderate disease. IPF may serve as a prognostic marker for disease severity in Covid-19 patients.