Projektiranje i analiza digitalnog sata

Sat je jedan od najstarijih ljudskih otkrića. U principu, potrebno je znati osnovne fizičke procese koji se ponavljaju s određenom učestalošću, i način da se izmjeri koliko taj proces traje. Kao što se godišnja doba i faze mjeseca mogu iskoristiti za mjerenje protoka određenih dužih perioda vremena, tako se i kraći periodi mogu koristiti za mjerenje sati i minuta. Sunčani sat koji mjeri vrijeme dana pomoću smjera sjenke koju baca određeni predmet osvjetljen suncem, bio je dobro poznat u drevnim vremenima. Pješčani satovi mjerili su vrijeme prolaskom sitnog pijeska kroz uzani otvor na staklenoj posudi. Razvoj elektronike u 20. stoljeću doveo je do satova bez ikakvog mehanizma. Vrijeme na ovakvim satovima mjerilo se na razne načine, na primjer pomoću kvarcnih kristala ili raspadanjem radioaktivnih elemenata. Čak su i mehanički satovi napajani baterijama, čime je navijanje sata postalo suvišno. Cilj ovog rada je projektirati i analizirati jedan digitalni zidni sat s integriranim krugom Maxim IC type DS3231 koji je kvalificiran od strane proizvođača kao „iznimno točan I2C sat u stvarnom vremenu (RTC), s integriranim temperaturno kompenziranim kristalnim oscilatorom (TCXO) i kristalom.“[1] Smatra se da integracija kristalnog rezonatora povećava dugotrajnu točnost uređaja, garantirajući maksimalnu pogrešku manju od 64 sekunde u godini, i temperaturni opseg od 0 do 40 °C (32 do 104 °F). Uređaj uključuje baterijski ulaz koji održava rad uređaja u odsutnosti vanjskog izvora.Clock is one of the oldest human inventions. In principle, it is necessary to know basic physical processes which are repeated with a certain frequency and method to measure how much this process lasts. Such as the season and phase of the month can be used to measure flow of certain lengthy periods of time, so are shorter periods used to measure hours and minutes. A sunidial shows the time by displaying the position of shadow on flat surface. Hourglasses measured time by passing of the fine sand through narrow opening on a glass container. The objective of this article is to project and analyze digital wall clock with Maxim IC type DS3231, qualified by its manufacturer as an „extremely accurate I2C real time clock (RTC) with integrated temperature compensated crystal oscillator (TCXO) and crystal.“ It is considered that integration of the crystal resonator enhances the long-term accuracy of derive, guaranteeing a maximum error of less than 64 seconds over a year, and over a temperature range 0 to 40 °C (32 to 104 °F). The device incorporates a battery input which maintains running of the device in the absence of external power

Non-classical Indications for Cardiac Resynchronization Therapy

Based on randomized controlled studies, cardiac resynchronization therapy (CRT) is currently indicated in patients with systolic heart failure of New York Heart Association (NYHA) functional class III and IV, left ventricular ejection fraction < 35% and wide QRS (>120 ms). Most of the enrolled patients were in sinus rhythm, were not previously paced and had mainly LBBB. Thus, there are uncertainties regarding several other populations, not included or underrepresented in the main studies. These populations include patients with atrial fibrillation (AF), previous pacemakers considered for upgrade to CRT, RBBB, narrow QRS < 120 ms, NYHA functional class <III, or right heart failure. These non-classical indications are herein reviewed.             Although CRT seems to benefit patients with AF and patients with preexisting pacemakers, in patients with NYHA functional class II-III, or with narrow QRS, or with RBBB, or in those with predominant right heart failure, the role of CRT is not established yet and further relevant clinical trials are needed

Truncating FLNC Mutations Are Associated With High-Risk Dilated and Arrhythmogenic Cardiomyopathies

BACKGROUND: Filamin C (encoded by the FLNC gene) is essential for sarcomere attachment to the plasmatic membrane. FLNC mutations have been associated with myofibrillar myopathies, and cardiac involvement has been reported in some carriers. Accordingly, since 2012, the authors have included FLNC in the genetic screening of patients with inherited cardiomyopathies and sudden death. OBJECTIVES: The aim of this study was to demonstrate the association between truncating mutations in FLNC and the development of high-risk dilated and arrhythmogenic cardiomyopathies. METHODS: FLNC was studied using next-generation sequencing in 2,877 patients with inherited cardiovascular diseases. A characteristic phenotype was identified in probands with truncating mutations in FLNC. Clinical and genetic evaluation of 28 affected families was performed. Localization of filamin C in cardiac tissue was analyzed in patients with truncating FLNC mutations using immunohistochemistry. RESULTS: Twenty-three truncating mutations were identified in 28 probands previously diagnosed with dilated, arrhythmogenic, or restrictive cardiomyopathies. Truncating FLNC mutations were absent in patients with other phenotypes, including 1,078 patients with hypertrophic cardiomyopathy. Fifty-four mutation carriers were identified among 121 screened relatives. The phenotype consisted of left ventricular dilation (68%), systolic dysfunction (46%), and myocardial fibrosis (67%); inferolateral negative T waves and low QRS voltages on electrocardiography (33%); ventricular arrhythmias (82%); and frequent sudden cardiac death (40 cases in 21 of 28 families). Clinical skeletal myopathy was not observed. Penetrance was >97% in carriers older than 40 years. Truncating mutations in FLNC cosegregated with this phenotype with a dominant inheritance pattern (combined logarithm of the odds score: 9.5). Immunohistochemical staining of myocardial tissue showed no abnormal filamin C aggregates in patients with truncating FLNC mutations. CONCLUSIONS: Truncating mutations in FLNC caused an overlapping phenotype of dilated and left-dominant arrhythmogenic cardiomyopathies complicated by frequent premature sudden death. Prompt implantation of a cardiac defibrillator should be considered in affected patients harboring truncating mutations in FLNC.Instituto de Salud Carlos III [PI11/0699, PI14/0967, PI14/01477, RD012/0042/0029, RD012/0042/0049, RD012/0042/0066, RD12/0042/0069]; Spanish Ministry of Economy and Competitiveness [SAF2015-71863-REDT]; Plan Nacional de I+D+I; Plan Estatalde I+D+I, European Regional Development Fund; Health in Code SLS

Electrocardiographic findings in patients with arrhythmogenic cardiomyopathy and right bundle branch block ventricular tachycardia

AIMS: Little is known about patients with right bundle branch block (RBBB)-ventricular tachycardia (VT) and arrhythmogenic cardiomyopathy (ACM). Our aims were: (i) to describe electrocardiogram (ECG) characteristics of sinus rhythm (SR) and VT; (ii) to correlate SR with RBBB-VT ECGs; and (iii) to compare VT ECGs with electro-anatomic mapping (EAM) data. METHODS AND RESULTS: From the European Survey on ACM, 70 patients with spontaneous RBBB-VT were included. Putative left ventricular (LV) sites of origin (SOOs) were estimated with a VT-axis-derived methodology and confirmed by EAM data when available.  Overall, 49 (70%) patients met definite Task Force Criteria. Low QRS voltage predominated in lateral leads (n = 37, 55%), but QRS fragmentation was more frequent in inferior leads (n = 15, 23%). T-wave inversion (TWI) was equally frequent in inferior (n = 28, 42%) and lateral (n = 27, 40%) leads. TWI in inferior leads was associated with reduced LV ejection fraction (LVEF; 46 ± 10 vs. 53 ± 8, P = 0.02). Regarding SOOs, the inferior wall harboured 31 (46%) SOOs, followed by the lateral wall (n = 17, 25%), the anterior wall (n = 15, 22%), and the septum (n = 4, 6%). EAM data were available for 16 patients and showed good concordance with the putative SOOs. In all patients with superior-axis RBBB-VT who underwent endo-epicardial VT activation mapping, VT originated from the LV. CONCLUSIONS: In patients with ACM and RBBB-VT, RBBB-VTs originated mainly from the inferior and lateral LV walls. SR depolarization and repolarization abnormalities were frequent and associated with underlying variants

Reply to Kataoka, N.; Imamura, T. How to Improve Clinical Outcomes in Patients with Tachycardia-Induced Cardiomyopathy. Comment on “Katz et al. Long-Term Outcomes of Tachycardia-Induced Cardiomyopathy Compared with Idiopathic Dilated Cardiomyopathy. <i>J. Clin. Med.</i> 2023, <i>12</i>, 1412”

In a letter to the editor titled “How to improve clinical outcomes in patients with tachycardia-induced cardiomyopathy”, Dr. Naoya Kataoka and Dr. Teruhiko Imamura [...

Long-Term Outcomes of Tachycardia-Induced Cardiomyopathy Compared with Idiopathic Dilated Cardiomyopathy

Background: data on the natural course and prognosis of tachycardia-induced cardiomyopathy (TICMP) and comparison with idiopathic dilated cardiomyopathies (IDCM) are scarce. Objective: To compare the clinical presentation, comorbidities, and long-term outcomes of TICMP patients with IDCM patients. Methods: a retrospective cohort study of patients hospitalized with new-onset TICMP or IDCM. The primary endpoint was a composite of death, myocardial infarction, thromboembolic events, assist device, heart transplantation, and ventricular tachycardia or fibrillation (VT/VF). The secondary endpoint was recurrent hospitalization due to heart failure (HF) exacerbation. Results: the cohort was comprised of 64 TICMP and 66 IDCM patients. The primary composite endpoint and all-cause mortality were similar between the groups during a median follow-up of ~6 years (36% versus 29%, p = 0.33 and 22% versus 15%, p = 0.15, respectively). Survival analysis showed no significant difference between TICMP and IDCM groups for the composite endpoint (p = 0.75), all-cause mortality (p = 0.65), and hospitalizations due to heart failure exacerbation. Nonetheless, the incidence of recurrent hospitalization was significantly higher in TICMP patients (incidence rate ratio 1.59; p = 0.009). Conclusions: patients with TICMP have similar long-term outcomes as those with IDCM. However, it portends a higher rate of HF readmissions, mostly due to arrhythmia recurrences

Long-Term Outcomes of Tachycardia-Induced Cardiomyopathy Compared with Idiopathic Dilated Cardiomyopathy

Background: data on the natural course and prognosis of tachycardia-induced cardiomyopathy (TICMP) and comparison with idiopathic dilated cardiomyopathies (IDCM) are scarce. Objective: To compare the clinical presentation, comorbidities, and long-term outcomes of TICMP patients with IDCM patients. Methods: a retrospective cohort study of patients hospitalized with new-onset TICMP or IDCM. The primary endpoint was a composite of death, myocardial infarction, thromboembolic events, assist device, heart transplantation, and ventricular tachycardia or fibrillation (VT/VF). The secondary endpoint was recurrent hospitalization due to heart failure (HF) exacerbation. Results: the cohort was comprised of 64 TICMP and 66 IDCM patients. The primary composite endpoint and all-cause mortality were similar between the groups during a median follow-up of ~6 years (36% versus 29%, p = 0.33 and 22% versus 15%, p = 0.15, respectively). Survival analysis showed no significant difference between TICMP and IDCM groups for the composite endpoint (p = 0.75), all-cause mortality (p = 0.65), and hospitalizations due to heart failure exacerbation. Nonetheless, the incidence of recurrent hospitalization was significantly higher in TICMP patients (incidence rate ratio 1.59; p = 0.009). Conclusions: patients with TICMP have similar long-term outcomes as those with IDCM. However, it portends a higher rate of HF readmissions, mostly due to arrhythmia recurrences