Atrial fibrillation--Where do we stand today?

Development and validation a nomogram for predicting new-onset postoperative atrial fibrillation following pulmonary resection

BACKGROUND

The new-onset postoperative atrial fibrillation (NOPAF) following pulmonary resection is a common clinical concern. The aim of this study was to construct a nomogram to intuitively predict the risk of NOPAF and offered protective treatments.

METHODS

Patients who underwent pulmonary resection between January 2018 and December 2020 were consecutively enrolled. Forward stepwise multivariable logistic regression analyses were used to screen independent predictors, and a derived nomogram model was built. The model performance was evaluated in terms of calibration, discrimination and clinical utility and validated with bootstrap resampling.

RESULTS

A total of 3583 patients who met the research criteria were recruited for this study. The incidence of NOPAF was 1.507% (54/3583). A nomogram, composed of five independent predictors, namely age, admission heart rate, extent of resection, laterality, percent maximum ventilation volume per minute (%MVV), was constructed. The concordance index (C-index) was 0.811. The nomogram showed substantial discriminative ability, with an area under the receiver operating characteristic curve of 0.811 (95% CI 0.758-0.864). Moreover, the model shows prominent calibration performance and higher net clinical benefits.

CONCLUSION

We developed a novel nomogram that can predict the risk of NOPAF following pulmonary resection, which may assist clinicians predict the individual probability of NOPAF and perform available prophylaxis. By using bootstrap resampling for validation, the optimal discrimination and calibration were demonstrated, indicating that the nomogram may have clinical practicality.

Pulmonary Disease, Pulmonary Hypertension and Atrial Fibrillation

Atrial fibrillation is associated with aging, obesity, heart disease, diabetes, and/or hypertension. Recent evidence suggests that parenchymal and vascular lung diseases increase atrial fibrillation risk. We review the epidemiology, clinical features, pathophysiologic mechanisms, and treatment implications of atrial fibrillation associated with diseases of the lungs and their vasculature, especially pulmonary hypertension. We also consider other features of pulmonary disease-associated atrial fibrillation. A key mediator of these conditions is right heart disease and right atrial remodeling. We pay particular attention to the pathophysiology and treatment challenges in atrial fibrillation associated with right heart disease induced by pulmonary diseases, including pulmonary hypertension.

Quantifying Risk Factors for Atrial Fibrillation: Retrospective Review of a Large Electronic Patient Database

BACKGROUND

Despite the numerous comorbidities associated with atrial fibrillation (AF), the relative risk has been varying and not well-documented.

AIM

To quantify the risk of diseases associated with AF.

METHODS

Population-based retrospective analysis in IBM Explorys (1999-2019), an electronic database with over 63 million patients in the United States. Odds ratios were calculated between AF and other diseases. AF patients were also stratified by age, gender, and race to assess trends of AF in different demographic groups.

RESULTS

1,812,620 patients had AF in the database. Congestive heart failure had the highest association with AF (OR 42.95). Cardiomyopathy, coronary artery disease, hypertension, and myocardial infarction all had odds greater than 15. Anemia of chronic disease and chronic kidney disease had odds greater than 18, the highest for chronic inflammatory conditions. Other conditions commonly associated with AF were found to have odds less than 8, including hyperthyroidism, alcohol use, and sleep apnea. Helicobacter pylori infection had the lowest odds at 1.98.

CONCLUSIONS

Epidemiologic information could be integrated with current clinical algorithms to more rapidly identify patients at risk of AF.

COPD in patients after heart transplantation is associated with a prolonged hospital stay, early posttransplant atrial fibrillation, and impaired posttransplant survival

Objectives

COPD is associated with reduced physical activity, an increased risk for pulmonary infections, and impaired survival in nontransplant patients. The aim of this study was to investigate the influence of COPD in patients after heart transplantation (HTX).

Methods

We performed an observational retrospective single-center study of 259 patients receiving HTX at Heidelberg University Hospital between 2003 and 2012. Patients were stratified by the Tiffeneau index (forced expiratory volume in 1 second/forced vital capacity [FEV1/FVC]) <0.70 before HTX. The analysis included demographics, posttransplant medication, length of the initial hospital stay after HTX, early posttransplant atrial fibrillation (AF), mortality, and causes of death.

Results

In total, 63 (24.3%) patients had an FEV1/FVC <0.70. These patients showed a prolonged hospital stay after HTX (52.0 days vs 43.4 days, mean difference (MD) = 8.6 days, 95% CI: 0.2, 17.0 days), a higher rate of early posttransplant AF (19.0% vs 8.2%, MD = 10.8%, 95% CI: 0.4%, 21.2%), and an increased 30-day mortality (9.5% vs 2.6%, HR = 3.79, 95% CI: 1.16, 12.40). Kaplan– Meier analysis showed a significant inferior 5-year survival in patients with an FEV1/FVC <0.70, along with a higher percentage of death due to transplant failure and infection/sepsis. In addition, a multivariate analysis for mortality within 5 years after HTX indicated an FEV1/FVC <0.70 as a significant risk factor for impaired 5-year posttransplant survival (HR =4.77, 95% CI: 2.76, 8.22).

Conclusion

COPD in patients after HTX is associated with a prolonged hospital stay, early posttransplant AF, and impaired posttransplant survival.

Experimental evaluation of the cardiac rhythm originating in myocardial sleeves of pulmonary veins using a monophasic action potential

Spontaneous depolarization similar to that from the sinus node was documented from the myocardial sleeves of pulmonary veins (PV) after isolation procedures. It was then hypothesized that sinus node-like tissue is present in the PVs of humans. Based on a number of features, the myocardium of myocardial sleeves (MS) is highly arrhythmogenic. Membrane potentials originating from MS are invariably recordable at the PVs ostia in patients with atrial fibrillation (AF) and delayed conduction around the PVs ostia may play a role in re-entry process responsible for the initiation and maintenance of AF. Diagnostic and therapeutic evidence of premature atrial beats induced in MS of PVs and resulting in launch of AF was detected by 3D electroanatomic method of monophasic action potential (MAP). MAP recording plays an important role in a direct view of human myocardial electrophysiology under both physiological and pathological conditions. Its crucial importance lies in the fact that it enables the study of the action potential of myocardial cell in vivo and, therefore, the study of the dynamic relation of this potential with all the organism variables. The knowledge of pathological MAPs from PV myocardial sleeves can help us to confirm a diagnosis when finding the similar action potential morphology. MAP can be also used to evaluate the therapeutic efficiency of vagal nerves suppression, radiofrequency ablation or other treatment procedures in PVs myocardial sleeves as well as for post-treatment following up.

Association of inflammation with atrial fibrillation in hyperthyroidism

Objectives

The aim of this study was to evaluate the relationship between inflammation and development of atrial fibrillation (AF) in patients with hyperthyroidism.

Methods

A total of 65 patients with newly diagnosed hyperthyroidism, 35 of whom were in sinus rhythm and 30 of whom in AF. Thirty five age- and gender-matched patients in a control group were included in the study. Factors associated with the development of AF were evaluated by multivariate regression analysis.

Results

Factors associated with AF in multivariate analysis included high sensitivity C reactive protein (HsCRP) [odds ratio (OR): 11.19; 95% confidence interval (95% CI): 1.80-69.53; P = 0.003], free T4 (OR: 8.76; 95% CI: 2.09–36.7; P = 0.003), and left atrial diameter (OR: 1.25; 95% CI: 1.06–1.47; P = 0.008).

Conclusions

The results of the present study suggest that HsCRP, an indicator of inflammation, free T4 and left atrial diameter are associated with the development AF in patients with hyperthyroidism.

The relationship between chronic atrial fibrillation and reduced pulmonary function in cases of preserved left ventricular systolic function

Background and Objectives

The purpose of this study was to investigate the relationship between chronic atrial fibrillation (AF) and reduced pulmonary function.

Subjects and Methods

Eighty-six chronic AF patients who were enrolled from annual health examination programs were studied using echocardiography and pulmonary function tests (PFT). Echocardiography and PFT matched for age, gender, and year performed were selected by the control group who had normal sinus rhythms. Patients with ejection fractions <50%, valvular heart disease, or ischemic heart disease were excluded.

Results

In the chronic AF patients, the forced expiratory volume at one second (FEV₁), FEV1%, and FEV₁/forced vital capacity (FVC) were significantly reduced, and the right ventricular systolic pressure was significantly increased. Episodes of heart failure were more frequently associated with the chronic AF patients than the controls. In particular, the FEV1% had the most meaningful relationship to chronic AF after an adjustment for cardiovascular risk factors {p=0.003, Exp (B)=0.978, 95% confidence interval (CI):0.963-0.993}.

Conclusion

Reduced FEV1%, which represents the severity of airway obstruction, was associated with chronic AF, and the greater the pulmonary function impairment, the greater the co-existence with AF and congestive heart failure in those with preserved left ventricular systolic function.