Correlation between baseline immature platelets fraction levels and peak troponin in patients with acute myocardial infarction.

INTRODUCTION: Elevated peak cardiac troponin levels have been linked with increased morbidity and mortality in patients with acute myocardial infarction (AMI). Immature Platelets are young and relatively large platelets that are hyper-reactive and pro-thrombotic compared to regular platelets. Increased immature platelet fraction (IPF) has been associated with an elevated risk of thrombotic events. We hypothesize that patients with higher IPF levels during AMI, will experience a more severe infarct, leading to elevated peak troponin levels. METHODS: Clinical data from patients admitted to the cardiology division between 2018 and 2022, who were diagnosed with AMI and underwent an IPF testing. Univariate and multivariate regression analyses were performed to identify predictors of elevated peak troponin. RESULTS: Among the 277 patients diagnosed with AMI who underwent IPF testing, 113 had (STEMI) and 164 had (NSTEMI). The median value of IPF of 4.2% was used as the threshold for defining elevated IPF. Notably, among STEMI patients, those with IPF ≥ 4.2% had significantly higher peak troponin levels ( P  = 0.021). Conversely, no significant difference in peak troponin levels was observed among NSTEMI patients ( P  = 0.348). Multivariate analysis identified patients with STEMI in the higher IPF group as one of the significant predictors for elevated peak troponin levels. CONCLUSION: This study revealed a correlation between higher baseline IPF levels and increased peak troponin levels specifically in STEMI patients, while no such association was found in NSTEMI patients. Incorporating IPF levels above the median into risk stratification scores for STEMI patients may provide valuable support for adopting a more proactive therapeutic approach.

The Prevalence of Cannabis-related Arrhythmias in Patients with Cancer: Real-world Data Evidence of Patient-reported Outcomes.

BACKGROUND: Cannabis consumption is suspected of causing arrhythmias and potentially sudden death. OBJECTIVES: To investigate prevalence and temporal relationships between cannabis use and onset of symptomatic arrhythmias among cancer patients using Belong.life, a digital patient powered network application. METHODS: Real-world data (RWD) were obtained through Belong.Life, a mobile application for cancer patients who use cannabis routinely. Patients replied anonymously and voluntarily to a survey describing their demographics, medical history, and cannabis use. RESULTS: In total, 354 cancer patients (77% female, 71% 50-69 years of age) replied: 33% were smokers and 49% had no co-morbidities. Fifteen had history of arrhythmias and two had a pacemaker; 64% started cannabis before or during chemotherapy and 18% had no chemotherapy. Cannabis indication was symptom relief in most patients. The mode of administration included oil, smoking, or edibles; only 35% were prescribed by a doctor. Cannabis type was delta 9-tetrahydrocannabinol > 15% in 43% and cannabidiol in 31%. After starting cannabis, 24 patients (7%) experienced palpitations; 13 received anti-arrhythmic drugs and 6 received anticoagulation. Eleven needed further medical investigation. Three were hospitalized. One had an ablation after starting cannabis and one stopped cannabis due to palpitations. Seven patients (2%) reported brady-arrhythmias after starting cannabis, but none needed pacemaker implantation. CONCLUSIONS: RWD showed that in cancer patients using cannabis, the rate of reported symptomatic tachy- and brady-arrhythmias was significant (9%) but rarely led to invasive treatments. Although direct causality cannot be proven, temporal relationship between drug use and onset of symptoms suggests a strong association.

A novel robotic radiation shielding device for electrophysiologic procedures: A prospective study.

BACKGROUND: A robotic Radiaction Shielding System (RSS) was developed to provide a full-body protection to all medical personnel during fluoroscopy-guided procedures, by encapsulating the imaging beam and blocking scattered radiation. OBJECTIVES: We aimed to evaluate its efficacy in real-world electrophysiologic (EP) laboratory- both during ablations and cardiovascular implantable electronic devices (CIED) procedures. METHODS: A prospective controlled study comparing consecutive real-life EP procedures with and without RSS using highly sensitive sensors in different locations. RESULTS: Thirty-five ablations and 19 CIED procedures were done without RSS installed and 31 ablations and 24 CIED procedures (17 with usage levels ≥70%) were done with RSS. Overall, there was 95% average usage level for ablations and 88% for CIEDs. For all procedures with ≥70% usage level and for all sensors, the radiation with RSS was significantly lower than radiation without RSS. For ablations, there was 87% reduction in radiation with RSS (76%-97% for different sensors). For CIEDs, there was 83% reduction in radiation with RSS (59%-92%). RSS usage did not increase procedure time and radiation time. User feedback showed a high-level of integration in the clinical workflow and safety profile for all types of EP procedures. CONCLUSIONS: For both CIED and ablation procedures the radiation with RSS was significantly lower than without RSS. Higher usage level brings higher reduction rates. Thus, RSS may have an important role in full-body protection to all medical personnel from scattered radiation during EP and CIED procedures. Until more data is available, it is recommended to maintain existing standard shielding.

Coronary artery disease among patients admitted with atrial fibrillation and chest pain.

INTRODUCTION: Patients who present to the emergency department with chest pain during an episode of atrial fibrillation (AF) impose a clinical challenge regarding the source of pain - being coronary artery disease (CAD) or AF in origin. The aim of this study was to identify clinical, imaging or laboratory markers which can predict significant CAD among patients with an AF episode and chest pain. METHODS: We included 57 consecutive patients admitted to our hospital with AF and chest pain. All patients underwent coronary evaluation. Significant CAD was defined as >50% stenosis in a major coronary artery by coronary angiography or cardiac CT. We compared CAD and non-CAD groups and analyzed risk factorsby regression analysis. RESULTS: Twenty-four patients (42%) were diagnosed with- and 33 patients (58%) without obstructive CAD. In a multivariate analysis of regional wall motion abnormality (RWMA), elevated troponin and hypertension were found to be predictors for CAD [odds ratio (OR), 22.4 (confidence interval (CI), 1.8-272.4; P = 0.02); OR, 5.6 (CI, 1-31.0; P = 0.05) and OR, 21.4 (CI, 1.6-284.6; P = 0.02), respectively]. There were no significant differences regarding the rate of typical chest pain at presentation in the CAD vs. the non-CAD group [13 (54%) vs. 20 (60%), P = 0.374], or in ECG ST-changes [12 (50%) vs.9 (27%), respectively; P = 0.08]. CONCLUSION: In patients who present acutely with chest pain and AF, troponin elevation and RWMA appear to be highly predictive of obstructive CAD, whereas clinical symptoms and ECG changes are not predictive. These findings may be helpful for guiding the management of patients admitted with AF and chest pain.

Inflammatory cytokines differ between patients with high versus low CHA2DS2-VASc scores in sinus rhythm-a possible mechanism for adverse cardiovascular events.

Background: The CHA2DS2-VASc score was shown to predict systemic thromboembolism and mortality in certain groups of patients in sinus rhythm (SR). Previous data showed that patients in SR with high CHA2DS2-VASc score have higher plasma levels of inflammatory markers such as sP-selectin and C-reactive protein. We further investigated this group. Methods: Blood samples were collected from consecutive patients in SR. Plasma was extracted and stored at -80 °C. Concentrations of a panel of soluble markers IL-1ß, IL-6, IL-8, IL-10, TNF-α and VEGF were measured by Magnetic Luminex Performance Assay. The PLF4 cytokine blood level was measured by ELISA. Results: 66 patients were enrolled (age 53 ± 18 years, 60% women). Patients with high CHA2DS2-VASc scores (n = 23) had significantly higher median IQR concentrations of TNF-α [10.34 (8.55,14.92) vs. 7.69 (6.06, 9.85) pg/ml, p = 0.009] and a trend towards higher levels of IL-1ß [0.59 (0.4,0.8) vs. 0.44 (0.31, 0.62) pg/ml, p = 0.07] and IL-8 [5.92 (4.5,9.4) vs. 5.04 (3.63, 6.04) pg/ml, p = 0.07], compared to the group with low scores (n = 43). Median IQR concentrations of VEGF, IL-6, IL-10 and PF4 did not significantly differ between the CHA2DS2-VASc score groups. Conclusion: Patients in SR with high versus low CHA2DS2-VASc scores have high plasma concentrations of systemic inflammation cytokines. The already proven high levels of sP-selectin, that promotes release of inflammatory cytokines from leukocytes, is in line with these results. This pro-inflammatory state in patients with high CHA2DS2-VASc scores, may explain the higher rate of adverse cardiovascular events associated with elevated CHA2DS2-VASc score even without atrial fibrillation.

Comparison of Factors Associated with Inflammation, Thrombosis, and Platelet Reactivity as well as Turnover between Patients with High versus Low CHA2DS2-VASc without Atrial Fibrillation.

BACKGROUND: The CHA2DS2-VASc score has been shown to predict systemic thromboembolism and mortality in certain groups in sinus rhythm (SR), similar to its predictive value with atrial fibrillation (AF). OBJECTIVES: To compare factors of inflammation, thrombosis, platelet reactivity, and turnover in patients with high versus low CHA2DS2-VASc score in SR. METHODS: We enrolled consecutive patients in SR and no history of AF. Blood samples were collected for neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), immature platelet fraction (IPF%) and count (IPC), CD40 ligand, soluble P-selectin (sP-selectin) and E-selectin. IPF was measured by autoanalyzer and the other factors by ELISA. RESULTS: The study comprised 108 patients (age 58 ± 18 years, 63 women (58%), 28 (26%) with diabetes), In addition, 52 had high CHA2DS2-VASc score (³ 2 for male and ³ 3 for female) and 56 had low score. Patients with low scores were younger, with fewer co-morbidities, and smaller left atrial size. sP-selectin was higher in the high CHA2DS2-VASc group (45, interquartile ratio [IQR] 36-49) vs. 37 (IQR 28-46) ng/ml, P = 0.041]. Inflammatory markers were also elevated, CRP 3.1 mg/L (IQR 1.7-9.3) vs. 1.6 (IQR 0.78-5.4), P < 0.001; NLR 2.7 (IQR 2.1-3.8) vs. 2.1 (IQR 1.6-2.5), P = 0.001, respectively. There was no difference in E-selectin, CD40 ligand, IPC, or IPF% between the groups. CONCLUSIONS: Patients in SR with high CHA2DS2-VASc score have higher inflammatory markers and sP-selectin. These findings may explain the higher rate of adverse cardiovascular events associated with elevated CHA2DS2-VASc score.

Echocardiography-guided Cardiac Implantable Electronic Device Implantation to Reduce Device Related Tricuspid Regurgitation: A Prospective Controlled Study.

BACKGROUND: Endocardial leads of permanent pacemakers (PPM) and implantable defibrillators (ICD) across the tricuspid valve (TV) can lead to tricuspid regurgitation (TR) or can worsen existing TR with subsequent severe morbidity and mortality. OBJECTIVES: To evaluate prospectively the efficacy of intraprocedural 2-dimentional-transthoracic echocardiography (2DTTE) in reducing/preventing lead-associated TR. METHODS: We conducted a prospective randomized controlled study comparing echocardiographic results in patients undergoing de-novo PPM/ICD implantation with intraprocedural echo-guided right ventricular (RV) lead placement (Group 1, n=56) versus non-echo guided implantation (Group 2, n=55). Lead position was changed if TR grade was more than baseline in Group 1. Cohort patients underwent 2DTTE at baseline and 3 and/or 6 months after implantation. Excluded were patients with baseline TR > moderate or baseline ≥ moderate RV dysfunction. RESULTS: The study comprised 111 patients (74.14 ± 11 years of age, 58.6% male, 19% ICD, 42% active leads). In 98 patients there was at least one follow-up echo. Two patients from Group 1 (3.6%) needed intraprocedural RV electrode repositioning. Four patients (3.5%, 2 from each group, all dual chamber PPM, 3 atrial fibrillation, 2 RV pacing > 40%, none with intraprocedural reposition) had TR deterioration during 6 months follow-up. One patient from Group 2 with baseline mild-moderate aortic regurgitation (AR) had worsening TR and AR within 3 months and underwent aortic valve replacement and TV repair. CONCLUSIONS: The rate of mechanically induced lead-associated TR is low; thus, a routine intraprocedural 2DTTE does not have a significant role in reducing/preventing it.

Effects of nifedipine on endothelial function, assessed by flow-mediated vasodilatation in pregnant patients.

OBJECTIVES: To evaluate the endothelial function, through flow-mediated vasodilation parameters from brachial artery test in women receiving nifedipine for acute tocolysis with threatened preterm delivery. METHODS: In a prospective study in a university-affiliated hospital, each participant served as herself control. We evaluated various parameters of endothelial function in 22 patients between 27 and 33 weeks of gestation with a diagnosis of threatened preterm delivery (TPTD) before and after 48 h of nifedipine treatment. Each patient received 80 mg nifedipine per day. The assessment tool was Brachial artery reactivity test (BART). Primary outcome was flow mediated vasodilation (FMD). RESULTS: The average participant's age was 27 ± 4.5 years, median gestational age of 28.5 weeks, BMI, kg/m2 (mean ± SD) 28.4 ± 3.3. Systolic blood pressure (mmHg) and diastolic blood pressure (mmHg) decreased from 108 ± 6 to 104 ± 5, p < .001 and from 66 ± 4 to 63 ± 4, p < .001, respectively. FMD (%) significantly decrease from 10.8 ± 6.1 to 7.2 ± 4.7, p = .03 prior to and after nifedipine treatment. The basal brachial artery diameter (mm) at rest was (3.19 ± 0.38 versus 3.39 ± 0.49, p = .28) before versus after nifedipine. The largest brachial artery diameter (mm) was (3.54 ± 0.35 versus 3.58 ± 0.44, p = .76) before versus after nifedipine. CONCLUSIONS: Our results suggest unfavorable changes in FMD probably as a result of nifedipine used for acute tocolysis. Future prospective studies should try to evaluate the safety of acute and maintenance tocolytic therapy with nifedipine on endothelial function in pregnant women.

[COMPLETE ATRIOVENTRICULAR BLOCK DUE TO PULMONARY EMBOLISM].

INTRODUCTION: Pulmonary embolism, a common and potentially fatal clinical condition, occurs when a blood thrombus becomes lodged in the pulmonary vasculature and creates an acute increment in the pulmonary vascular resistance, which, in turn, creates a right ventricular strain. Among the more familiar electrocardiographic manifestations in acute pulmonary embolism is sinus tachycardia, right bundle branch block and ST-T abnormalities in the right precordium leads. Complete heart block or any type of bradycardia is uncommon. In our case report we present an 81 years old woman who was admitted to our institution with acute pulmonary embolism and complete atrioventricular block, which later resolved with appropriate anticoagulation therapy.

Comparison of Immature Platelet Fraction and Factors Associated with Inflammation, Thrombosis and Platelet Reactivity Between Left and Right Atria in Patients with Atrial Fibrillation.

BACKGROUND: Recent trials found poor temporal relationship between atrial fibrillation (AF) episodes and strokes. Thus, stroke in AF patients probably involves more mechanisms than cardiac embolism. We compared factors of inflammation, thrombosis and platelet reactivity between left (LA) and right atria (RA) and femoral vein (FV) in patients with AF. METHODS: Blood samples were collected from patients undergoing AF-ablation from the FV, RA and LA for neutrophil to lymphocyte ratio (NLR), immature platelet fraction (IPF) and count (IPC), CD40 ligand, P-selectin and E-Selectin. IPF was measured by an autoanalyzer; CD40 ligand, P-selectin, and E-Selectin were measured by ELISA and NLR was calculated from complete blood counts. RESULTS: Sixty-seven patients were included (age 65±10y, 63% male, CHA2DS2-VASc score 2.8±1.8, LA volume index 40±24 mL/m2, 63% paroxysmal AF). There was no difference between FV, RA and LA regarding NLR and CD40 ligand. Factors associated with platelets activity: P-selectin, IPC and IPF% were higher in RA vs LA (60.3 IQR 49.0-76.4 ng/ml vs. 59.3 IQR 49.0-74.7, respectively, p=0.03 for P-selectin, 7.5 IQR 5.2-10 103/µL vs. 7.1 IQR 5-9.8, p<0.01 for IPC, and 3.6 IQR 2.7-5.0 % vs. 3.6 IQR 2.6-4.8, p<0.01 for IPF%). Similar trends were for E-selectin (41.2 IQR 31.1-51.2 ng/mL vs. 38.7 IQR 27.9-50.4 p=0.09). Similar significant differences were found in patients with CHA2DS2-VASC≥2 but not in patients with low score. CONCLUSIONS: Patients with AF, especially those with CHA2DS2-VASc≥2, have higher markers of thrombogenicity in RA compared to LA. There was no difference in inflammatory properties between the atria.

Temporal trends in prognosis of patients with acute coronary syndrome complicated by ventricular tachyarrhythmia.

OBJECTIVES: To evaluate clinical characteristics and prognosis of patients presented with acute coronary syndrome (ACS) that developed ventricular tachyarrhythmia VTA and to analyse it according to the period of presentation. BACKGROUND: VTA is an infrequent yet serious complication of ACS. There is limited data regarding the incidence and prognostic implications of VTA in the last decade as compared with the previous decade. METHODS: We evaluated clinical characteristics, major adverse cardiovascular events, short and long- term mortality of patients hospitalised with ACS who were enrolled in the Acute Coronary Syndrome Israeli Survey (ACSIS) during the years 2000-2016. Patients were classified into three groups: no VTA, early VTA (≤48 hours of onset) and late VTA (>48 hours of onset). Data were analysed according to the period of presentation: early vs late period (years 2000-2006 and 2008-2016 accordingly). RESULTS: The study population comprised 15,200 patients. VTA occurred in 487 (3.2%) patients. Early VTA presented in 373/487 (77%) patients and late VTA in 114/487 (23%) patients. VTA's, occurring in ACS patients were associated with increased risk of in-hospital, 30-days, 1-year and 5-year mortality rates during both early and late periods compared with no VTA. Moreover, late VTA was associated with the highest mortality rate with up to 65% in 5-year follow up (P < .001). Nevertheless, late VTA was associated with a lower mortality rate in the late period compared with the early period. CONCLUSIONS: Any VTA following ACS was associated with high short- and long-term mortality rate. However, over the late period, there has been a significant improvement in survival rates, especially in patients with late VTA. This may be attributed to early and invasive reperfusion therapy, implantable cardioverter-defibrillator implantation and better medical treatment.

The relationship between plasma vitamin D level and heart valves calcification in acute coronary syndrome and non acute coronary syndrome patients.

BACKGROUND: There is conflicting data regarding the association between low levels of plasma vitamin D and ischemic heart disease. We aimed to investigate the relationship between plasma vitamin D levels and heart valve calcification in hospitalized patients with ischemic heart disease versus non-ischemic heart disease controls. METHODS: A prospective case-control study comprising two age and gender-matched groups. The study group included consecutive patients hospitalized due to acute coronary syndrome; the control group included consecutive non-ischemic heart disease patients hospitalized for noncardiac causes. Blood samples for 25-hydroxyvitamin D level were drawn. An echocardiogram was performed during the first 3 days of hospitalization and reviewed for presence and degree of valvular calcification. RESULTS: Forty patients with acute coronary syndrome and 40 controls (age 58 ± 11 years, 64% male in both groups) were included. Mean plasma 25-hydroxyvitamin D vitamin level in the entire cohort was 24.5 ± 8 ng/ml. Valve calcification rates were similar in acute coronary syndrome versus non-acute coronary syndrome group (28 vs. 21 had valvular calcification; 18 vs. 12 had aortic valve calcification; 21 vs. 14 had mitral valve calcification, respectively; P = NS for all). We found no significant relationship between vitamin D level and valvular calcification, aortic valve calcification, or mitral valve calcification rate or degree in the entire cohort and in each group alone (P = NS for all). There was a negative correlation between 25-hydroxyvitamin D levels and age in the acute coronary syndrome group (r = -0.399, P = 0.012). CONCLUSIONS: We did not find a significant relationship between plasma vitamin D levels and the rate or degree of calcification of either aortic/mitral/both valves in hospitalized patients with or without ischemic heart disease.

Polymorphic ventricular tachycardia, ischaemic ventricular fibrillation, and torsade de pointes: importance of the QT and the coupling interval in the differential diagnosis.

AIMS: Distinctive types of polymorphic ventricular tachycardia (VT) respond differently to different forms of therapy. We therefore performed the present study to define the electrocardiographic characteristics of different forms of polymorphic VT. METHODS AND RESULTS: We studied 190 patients for whom the onset of 305 polymorphic VT events was available. The study group included 87 patients with coronary artery disease who had spontaneous polymorphic VT triggered by short-coupled extrasystoles in the absence of myocardial ischaemia. This group included 32 patients who had a long QT interval but nevertheless had their polymorphic VT triggered by ectopic beats with short coupling interval, a subcategory termed 'pseudo-torsade de pointes] (TdP). For comparison, we included 50 patients who had ventricular fibrillation (VF) during acute myocardial infarction ('ischaemic VF' group) and 53 patients with drug-induced TdP ('true TdP' group). The QT of patients with pseudo-TdP was (by definition) longer than that of patients with polymorphic VT and normal QT (QTc 491.4 ± 25.2 ms vs. 447.3 ± 55.6 ms, P < 0.001). However, their QT was significantly shorter than that of patients with true TdP (QTc 564.6 ± 75.6 ms, P < 0.001). Importantly, the coupling interval of the ectopic beat triggering the arrhythmia was just as short during pseudo-TdP as during polymorphic VT with normal QT (359.1 ± 38.1 ms vs. 356.6 ± 39.4 ms, P = 0.467) but was much shorter than during true TdP (581.2 ± 95.3 ms, P < 0.001). CONCLUSIONS: The coupling interval helps discriminate between polymorphic VT that occurs despite a long QT interval (pseudo-TdP) and polymorphic arrhythmias striking because of a long QT (true TdP).

Immature platelet fraction over time and clinical outcomes in patients with acute myocardial infarction.

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.

Migration of a new generation implantable loop recorder: a case report.

BACKGROUND: Implantable loop recorders (ILR) are widely used in patients with syncope, palpitations, or cryptogenic stroke. Implantable loop recorder implantation is considered a minimally invasive, low-risk procedure, however, rare complications can occur, including device migration. CASE SUMMARY: A 65-year-old woman underwent implantation of the new generation Biotronik ILR-BioMonitor 3-at a typical, standard location as part of recurrent syncope workup. The procedure was unremarkable, without acute complications. The remote communication with the device was lost 1 week later. Chest X-ray and chest computed tomography confirmed device migration into the left postero-inferior part of the pleural cavity. We were able to establish direct device communication from the patients' dorsum (back). The device was retrieved with forceps during thoracoscopy without further complications. DISCUSSION: There are few published cases of ILR migration into the pleural cavity. To our knowledge, this is the first published case of subpleural penetration of the new generation of Biotronik ILR (BioMonitor 3) which is small in size and has a sharp antenna. We assume that the ILR migrated about a week post-implantation. We suggest that the subcutaneous implantation be done with a minimal penetration angle and parallel to the sternum with close follow-up after the procedure.

Immature platelets in patients hospitalized with Covid-19.

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 AMI group (10.8 × 109/L [8.3-18.1], 7.35 × 109/L [5.3-10.5], 10.7 × 109/L [7.7-16.8], respectively, P < 0.0001). The maximal IPF% among the Covid-19 group was higher than the stable group and similar to the AMI group. The maximal IPC in Covid-19 was higher than the maximal IPC in both the stable and AMI groups (COVID-19: 14.4 × 109/L [9.4-20.9], AMI: 10.9 × 109/L [7.6-15.2], P = 0.0035, Stable: 7.55 × 109/L [5.55-10.5], P < 0.0001). Patients with Covid-19 have increased immature platelets indices compared to stable patients with cardiovascular risk factors, and as the disease progresses also compared to AMI patients. The enhanced platelet turnover and reactivity may have a role in the development of thrombotic events in Covid-19 patients.

Evaluation of left atrial remodeling by 2D-speckle-tracking echocardiography versus by high-density voltage mapping in patients with atrial fibrillation.

BACKGROUND: Strain imaging during left atrial (LA) reservoir phase (LASr) is used as a surrogate for LA structural remodeling and fibrosis. Atrial fibrillation (AF) patients with >5% low-voltage zones (LVZs) obtained by 3D-electro-anatomical-mapping have higher recurrence rate post-ablation. We investigated the relationship between LA remodeling using two-dimensional-speckle-tracking echocardiography (2D-STE) and high-density voltage mapping in AF patients. METHODS: A prospective study of 42 consecutive patients undergoing AF ablation. 2D-echo, 2D-STE, and high-density contact LA bipolar voltage maps were constructed before ablation. LVZs were determined with different bipolar amplitudes and their ratio per patient's LA area were investigated for correlation with LASr. We compared 2D-LASr results in patients with LVZs ≥ 5% (LVZs group) versus those with LVZ < 5% (non-LVZs group). RESULTS: Compared with non-LVZs group (n = 15), LVZs group (n = 27) included significantly older patients, more women, more persistent AF, higher CHA2 DS2 -VASc score, higher E/A ratio and higher LA volume index (p < .05). LVZs group had lower %LASr values (12.4 ± 5.9% vs. 21.1 ± 6.3, respectively; p<.001). LVZs% in different amplitudes (<0.1 mV, <0.2 mV, and <0.5 mV) were negatively correlated with %LASr (r = -.63, r = -.68, and r = -.72, respectively; p< .001). Atrial strain thresholds for LVZs ≥ 5% in amplitudes <0.1 mV, <0.2 mV, and <0.5 mV were associated with %LASr 12.98, 16.16 and 19.55, respectively; p< .05). In a multivariate analysis, %LASr was the only independent indicator of LVZs (OR, 0.8; 95% CI, 0.6-0.9; p= .04). CONCLUSIONS: LVZs ≥ 5% has a negative association with atrial %LASr. Thus, a simple 2D-STE measurement of %LASr can be used as a noninvasive method to evaluate significant LA remodeling and fibrosis in AF patients.