Prognostic Value of Preoperative Electrocardiogram in Low-Risk Patients Undergoing Surgical Intervention and General Anesthesia

BACKGROUND

Patients aged over 50 years require four times more surgical interventions than younger groups. Many guidelines recommend the performance of preoperative electrocardiogram (ECG) in this population.

OBJECTIVES

To determine the value of preoperative ECG in patients aged over 50 years and classified as ASA I-II (surgical risk).

METHODS

Patients older than 50 years, without comorbidities, who underwent surgical intervention and general anesthesia were included in the study. Patients were randomized to undergo ECG (group A, n=214) or not (group B, n=213) in the preoperative period. The following variables were analyzed: sex, age, ECG, chest x-ray and laboratory tests results, surgical risk, surgery duration, adverse events and in-hospital mortality. The level of significance was set at 5%.

RESULTS

Adverse outcomes were reported in 23 (5.4%) patients, with a significant number of adverse events in male patients (OR=7.91 95%CI 3.3-18.90, p<0.001) and in those undergoing major surgeries (OR=30.02 95%CI 4.01-224.92, p<0.001). No differences were observed between patients who underwent ECG and those who did not (OR=1.59, 95%CI, 0.67-3.75, p=0.289). No significant differences were found in the other variables. In multivariate logistic regression, male sex (OR = 6.49; 95%CI 2.42-17.42, p<0.001) and major surgery (OR=22.62; 95%CI 2.95-173.41, p=0.002) were independent predictors of adverse outcomes, whereas undergoing (or not) ECG (OR=1.09; IC95% 0.41-2.90, p=0.867) remained without statistical significance.

CONCLUSION

Our findings suggest that preoperative ECG could not predict an increased risk of adverse outcomes in our study population during the hospital phase.

Prolongation of the QTc Interval at Admission is Associated with Increased Mortality in Patients with SARS-COV-2 during Hospitalization

BACKGROUND

Cardiovascular involvement associated with SARS-COV-2 infection is related to unfavorable outcomes during hospitalization. Therefore, the measurement at the admission of the QTc interval on the 12-lead electrocardiogram may be a prognostic marker.

OBJECTIVE

To identify the relationship between QTc prolongation at admission during hospitalization and mortality from SARS-COV-2.

METHOD

Observational study based on a retrospective cohort of patients with confirmed SARS-COV-2 infection from San Ignacio University Hospital, Bogotá (Colombia), between March 19, 2020, and July 31, 2021. Mortality was compared in patients with prolonged and normal QTc at admission after controlling by clinical variables and comorbidities using bivariate and multivariate logistic regression models. A p-value <0.05 was considered statistically significant.

RESULTS

1296 patients were analyzed, and 127 (9.8%) had prolonged QTc. Mortality was higher in patients with prolonged QTc (39.4% vs 25.3%, p=0.001), as was hospital stay (median 11vs.8 days; p=0.002). In the multivariate analysis, mortality was associated with prolonged QTc (OR 1.61, 95% CI: 1.02; 2.54, p=0.038), age (OR 1.03, 95% CI 1.02; 1.05, p<0.001), male sex (OR 2.15, 95% CI 1.60; 2.90, p <0.001), kidney disease (OR 1.32, 95% CI 1.05; 1.66, p =0.018) and Charlson comorbidity index > 3 (OR 1.49, 95% CI 1.03; 2.17, p=0.035).

CONCLUSIONS

Hospital mortality due to SARS-COV-2 is associated with prolonging the QTc interval at the time of admission, even after adjusting for age, sex, comorbidities, and basal severity of infection. Additional research is needed to establish whether these findings are related to cardiac involvement by the virus, hypoxia, and systemic inflammation.

F Wave Amplitude as a Predictor of Thromboembolism and Success of Electrical Cardioversion in Patients with Persistent Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) is classified according to the amplitude of fibrillatory waves (f) into fine waves (fAF) and coarse waves (cAF).

OBJECTIVES

To correlate the amplitude of f waves with clinical, laboratory, electrocardiographic, and echocardiographic variables that indicate a high risk of thromboembolism and to assess their impact on the success of electrical cardioversion (ECV).

METHODS

Retrospective, observational study that included 57 patients with persistent non-valvular AF who underwent ECV. The maximum amplitude of f waves was measured in lead V1. cAF was defined when f ≥ 1.0mm and fAF when f < 1.0mm. The findings were correlated with the indicated variables. Values of p < 0.05 were considered statistically significant.

RESULTS

cAF (n = 35) was associated with greater success in ECV (94.3% vs. 72.7%, p = 0.036) even after adjusting for variables such as age and BMI (p = 0.026, OR = 11.8). Patients with fAF (n = 22) required more shocks and more energy to revert to sinus rhythm (p = 0.019 and p = 0.027, respectively). There was no significant association between f-wave amplitude and clinical, echocardiographic, and laboratory parameters.

CONCLUSIONS

The amplitude of f wave was not associated with echocardiographic, clinical and laboratory parameters that indicate a high risk of thromboembolism. cAF was associated with a higher chance of success reverting to sinus rhythm employing ECV. A greater number of shocks and energy were required for reversion to sinus rhythm in patients with fAF.