Effect of COVID-19 on cardiorenal axis: known or unknown universe?

Recent findings have confirmed relationships between coronavirus disease (COVID-19) and multiple organ dysfunction. The prevalence of cardiac and renal involvement in COVID-19 has been increasingly reported and is a marker of severe disease that not only directly or indirectly affects the organs, but may also exacerbate the underlying comorbid illness. In addition, patients affected by the new coronavirus present a systemic inflammatory condition that results in damage to several tissues, especially the heart, kidneys, and vessels. It is well known that the heart and kidneys are closely related, so that any change in one of the organs can lead to damage to the other, establishing the so-called cardiorenal syndrome. Herein, we explore some case reports of patients with COVID-19 who had heart and kidney abnormalities, consequently resulting in worse prognosis of the disease. These results highlight the importance of understanding the cause and effect between the cardiac and renal systems and the course of early SARS-CoV-2 infection.

Ca2+/Calmodulin-dependent kinase II delta B is essential for cardiomyocyte hypertrophy and complement gene expression after LPS and HSP60 stimulation in vitro

Inflammation plays an important role in the development of cardiovascular diseases (CVDs), suggesting that the immune system is a target of therapeutic interventions used for treating CVDs. This study evaluated mechanisms underlying inflammatory response and cardiomyocyte hypertrophy associated with bacterial lipopolysaccharide (LPS)- or heat shock protein 60 (HSP60)-induced Toll-like receptor (TLR) stimulation and the effect of a small interfering RNA (siRNA) against Ca2+/calmodulin-dependent kinase II delta B (CaMKIIδB) on these outcomes. Our results showed that treatment with HSP60 or LPS (TLR agonists) induced cardiomyocyte hypertrophy and complement system C3 and factor B gene expression. In vitro silencing of CaMKIIδB prevented complement gene transcription and cardiomyocyte hypertrophy associated with TLR 2/4 activation but did not prevent the increase in interleukin-6 and tumor necrosis factor-alfa gene expression in primary cultured cardiomyocytes. Moreover, CaMKIIδB silencing attenuated nuclear factor-kappa B expression. These findings supported the hypothesis that CaMKIIδB acts as a link between inflammation and cardiac hypertrophy. Furthermore, the present study is the first to show that extracellular HSP60 activated complement gene expression through CaMKIIδB. Our results indicated that a stress stimulus induced by LPS or HSP60 treatment promoted cardiomyocyte hypertrophy and initiated an inflammatory response through the complement system. However, CaMKIIδB silencing prevented the cardiomyocyte hypertrophy independent of inflammatory response induced by LPS or HSP60 treatment.

Reproducibility of heart rate variability parameters measured in healthy subjects at rest and after a postural change maneuver

Heart rate variability (HRV) provides important information about cardiac autonomic modulation. Since it is a noninvasive and inexpensive method, HRV has been used to evaluate several parameters of cardiovascular health. However, the internal reproducibility of this method has been challenged in some studies. Our aim was to determine the intra-individual reproducibility of HRV parameters in short-term recordings obtained in supine and orthostatic positions. Electrocardiographic (ECG) recordings were obtained from 30 healthy subjects (20-49 years, 14 men) using a digital apparatus (sampling ratio = 250 Hz). ECG was recorded for 10 min in the supine position and for 10 min in the orthostatic position. The procedure was repeated 2-3 h later. Time and frequency domain analyses were performed. Frequency domain included low (LF, 0.04-0.15 Hz) and high frequency (HF, 0.15-0.4 Hz) bands. Power spectral analysis was performed by the autoregressive method and model order was set at 16. Intra-subject agreement was assessed by linear regression analysis, test of difference in variances and limits of agreement. Most HRV measures (pNN50, RMSSD, LF, HF, and LF/HF ratio) were reproducible independent of body position. Better correlation indexes (r > 0.6) were obtained in the orthostatic position. Bland-Altman plots revealed that most values were inside the agreement limits, indicating concordance between measures. Only SDNN and NNv in the supine position were not reproducible. Our results showed reproducibility of HRV parameters when recorded in the same individual with a short time between two exams. The increased sympathetic activity occurring in the orthostatic position probably facilitates reproducibility of the HRV indexes.

Endocarditis infecciosa en la República Argentina (Estudio E.I.R.A.): resultados generales / Infective endocarditis in Argentina: general results

Se describen 294 episodios de endocarditis infecciosa en 285 pacientes con predominio del sexo masculino y edad promedio de 54,1 años. El 55,5 por ciento tenía cardiopatía subyacente y en el 63,3 por ciento se encontró un evento predisponente. La signosintomatología resultó inespecífica y el tiempo promedio previo al diagnóstico fue de 33 ñ 34 días. En el 83 por ciento de los casos se visualizaron vegetaciones por eco. El 30 por ciento de los pacientes presentó insuficiencia cardíaca severa. El compromiso izquierdo se observó en 232 casos (39 por ciento aórticos, 29 por ciento mitrales y 11 por ciento mitroaórticos); la tricúspide estuvo comprometida en 40 oportunidades y la pulmonar en 3 (14,8 por ciento). La clasificación de Duke presentó mayor sensibilidad diagnóstica

Endocarditis infecciosa en pacientes drogadictos endovenosos: presentación clínica y evolución intrahospitalaria / Infective endocarditis in intravenous drug users

Este estudio analizó las características de cuarenta episodios de endocarditis infecciosa en 38 pacientes con drogadicción intravenosa como factor predisponente. Tenían una edad promedio de 28,9 años; 90 por ciento eran de sexo masculino, con compromiso de válvula sana en 82,5 por ciento de los casos; 20 por ciento de los pacientes habían tenido un episodio o más de endocarditis previa; 77,5 por ciento tuvieron afectación derecha; el agente causal más frecuente fue el Staphylococcus aureus, con 70 por ciento de hemocultivos positivos y 90 por ciento de incidencia de HIV. Las complicaciones más frecuentes fueron la insuficiencia cardíaca y el tromboembolismo de pulmón.La mortalidad hospitalaria fue más elevada que la descripta habitualmente en esta población

Endocarditis infecciosa en la República Argentina: complicaciones y mortalidad / Infective endocarditis in Argentina: complications and mortality

En 294 episodios de endocarditis infecciosa se observaron 208 (70,8 por ciento) complicaciones. El 55 por ciento fueron cardíacas, principalmente insuficiencia cardíaca por compromiso aórtico o mitroaórtico. En 9 por ciento de los casos se observaron abscesos anulares, más frecuentemente en las endocarditis infecciosas protésicas. Se observaron 76 embolias, de las cuales 35 fueron en el sistema nervioso central, 21 pulmonares y 10 en miembros. Se diagnosticaron 10 aneurismas micóticos cerebrales con 80 por ciento de mortalidad. La mortalidad hospitalaria fue del 23,5 por ciento y se correlacionó con cuadro séptico severo, insuficiencia cardíaca y embolismo sistémico