A Gravidade da Doença Afeta os Parâmetros de Repolarização Ventricular em Pacientes com COVID-19 / Disease Severity Affects Ventricular Repolarization Parameters in Patients With COVID-19

Resumo Fundamento: Não há estudos avaliando o intervalo Tpico-Tfim (Tpe), a relação Tpe/QT e a relação Tpe/QTc para avaliar arritmias cardíacas em pacientes com COVID-19. Objetivo: Visamos investigar se há alterações nos intervalos QT, QTc e Tpe e nas relações Tpe/QT e Tpe/QTc em pacientes com COVID-19. Métodos: O estudo incluiu 90 pacientes com infecção por COVID-19 e 30 controles saudáveis pareados por sexo e idade. Foram aferidos os intervalos QT, QTc e Tpe e as relações Tpe/QT e Tpe/QTc. Os participantes incluídos no estudo foram divididos nos seguintes 4 grupos: controles saudáveis (grupo I), pacientes com COVID-19 sem pneumonia (grupo II), pacientes com COVID-19 e pneumonia leve (grupo III) e pacientes com COVID-19 e pneumonia grave (grupo IV). Significância estatística foi definida por valor p < 0,05. Resultados: Verificou-se que a frequência cardíaca basal, a presença de hipertensão e diabetes, a contagem de leucócitos, o nitrogênio ureico no sangue, a creatinina, o potássio, o aspartato aminotransferase, a alanina aminotransferase, o NT-proBNP, a proteína C reativa de alta sensibilidade, o dímero-D, a TncI-as, o intervalo Tpe, a relação Tpe/QT e a relação Tpe/QTc aumentaram do grupo I para o grupo IV e foram significativamente mais altos em todos os pacientes do grupo IV (p < 0,05). A pressão arterial sistólica, a hemoglobina e os níveis de cálcio eram menores no grupo IV e significativamente menores em comparação com os demais grupos (< 0,05). Os intervalos QT e QTc eram semelhantes entre grupos. Determinou-se que os níveis elevados de frequência cardíaca, cálcio, dímero-D, NT-proBNP e PCR-as eram significativamente relacionados a Tpe, Tpe/QT e Tpe/QTc. Conclusões: Em pacientes com COVID-19 e pneumonia grave, o intervalo Tpe, a relação Tpe/QT e a relação Tpe/QTc, que estão entre os parâmetros de repolarização ventricular, foram aumentados, sem prolongação dos intervalos QT e QTc. A partir deste estudo, não podemos definitivamente concluir que as alterações eletrocardiográficas observadas estão diretamente relacionadas à infecção por COVID-19 ou à inflamação, mas sim associadas a cenários graves de COVID-19, que podem envolver outras causas de inflamação e comorbidades.

Abstract Background: There is no study evaluating the Tpeak-Tend (Tpe) interval, Tpe/QT ratio, and Tpe/QTc ratio to assess cardiac arrhythmias in patients with COVID-19. Objective: We aimed to examine whether there is a change in QT, QTc, Tpe interval, Tpe/QT ratio, and Tpe/QTc ratio in patients with COVID-19. Methods: The study included 90 patients with COVID-19 infection and 30 age-and-sex-matched healthy controls. QT, QTc, Tpe interval, Tpe/QT ratio, and Tpe/QTc ratio were measured. The participants included in the study were divided into the following 4 groups: healthy controls (group I), patients with COVID-19 without pneumonia (group II), patients with COVID-19 and mild pneumonia (group III), and patients with COVID-19 and severe pneumonia (group IV). Statistical significance was set at p < 0.05. Results: It was found that baseline heart rate, presence of hypertension and diabetes, white blood cell count, blood urea nitrogen, creatinine, potassium, aspartate aminotransferase, alanine aminotransferase, NT-proBNP, high sensitive C reactive protein, D-dimer, hs-cTnI, Tpe, Tpe/QT, and Tpe/QTc increased from group I to group IV, and they were significantly higher in all patients in group IV (p < 0.05). Systolic-diastolic blood pressure, hemoglobin, and calcium levels were found to be lowest in group IV and significantly lower than in other groups (< 0.05). QT and QTc intervals were similar between groups. It was determined that increased heart rate, calcium, D-dimer, NT-proBNP and hs-CRP levels were significantly related to Tpe, Tpe/QT, and Tpe/QTc. Conclusions: In patients with COVID-19 and severe pneumonia, Tpe, Tpe/QT ratio, and Tpe/QTc ratio, which are among ventricular repolarization parameters, were found to be increased, without prolonged QT and QTc intervals. In this study, we cannot definitively conclude that the ECG changes observed are directly related to COVID-19 infection or inflammation, but rather associated with severe COVID-19 scenarios, which might involve other causes of inflammation and comorbidities. (Arq Bras Cardiol. 2020; 115(5):907-913)

Lead aVR is a predictor for mortality in heart failure with preserved ejection fraction

Background Normally, lead augmented vector right (aVR) has a negative T wave polarity (TaVR) in the electrocardiography (ECG). Positive TaVR and ST segment deviation in lead aVR (STaVR) have negative effects on mortality in heart failure with reduced ejection fraction patients. Aim Our aim was to investigate the relationship between lead aVR changes and mortality in heart failure with preserved ejection fraction (HFpEF) patients. Methods We retrospectively examined 249 patients in 2011–2015 years (mean age 70.8 ± 11.9 years and follow-up period 38.3 ± 9.6 months). ECG, echocardiographic, and laboratory findings were recorded and compared in the study. Existence of positive TaVR, STaVR, and quantitative TaVR values were recorded and the absolute numerical values of TaVR and STaVR were recorded from the 12-lead surface ECG (T/STaVR ratio or vice versa). Results The patients were divided into two groups: living (171) and deceased (78). Age, systolic blood pressure, left atrial diameter, QRS duration, positive TaVR frequency, STaVR, absolute value of TaVR, and ratio were significantly higher in the deceased group. Age (OR: 1.106), STaVR (OR: 2.349), TaVR (OR: 1.612), and T/STaVR ratio (OR: 5.156) were determined as independent predictors for mortality. Conclusions ST segment and T wave polarity changes in lead aVR closely associated with mortality in patients with HfpEF.