The burden of atrial fibrillation and its prognostic value in patients with dilated cardiomyopathy

Left ventricular diastolic dysfunction worsens prognosis in patients with heart failure due to dilated cardiomyopathy

AIMS

The prognostic significance of left ventricular (LV) diastolic dysfunction (LVDD) severity in patients with dilated cardiomyopathy (DCM) remains uncertain. This study aimed to evaluate the association of LVDD severity and elevated left atrial pressure (eLAP) with patient outcomes in stable, non-acutely decompensated patients with DCM.

METHODS

This single-centre, retrospective, observational study involved 740 DCM patients (either inpatients or outpatients) managed at our tertiary cardiac centre between 2010 and 2021. Due to incomplete data, 96 patients were excluded. LVDD and eLAP were assessed using echocardiography according to the 2016 guidelines of the European Association of Cardiovascular Imaging (EACVI). The primary outcomes were all-cause mortality and heart failure (HF)-related mortality.

RESULTS

The final cohort comprised of 644 DCM patients [mean age: 52 ± 12 years, LV ejection fraction (LVEF): 26 ± 10%]. Over a median follow-up period of 41 (18.5-66.7) months, 105 (16.3%) patients died: 8 (5.3%) patients in the normal left atrial pressure (nLAP) group and 97 (19.6%) patients in the eLAP group. eLAP was identified as an independent prognostic factor for both all-cause mortality [hazard ratio (HR) 2.0; 95% confidence interval (CI) 1.1-3.7; P = 0.01] and HF-related mortality (HR 2.5; 95% CI 1.01-6.5; P = 0.04), even after adjusting for LVEF and atrial fibrillation (AF) presence. Additionally, HF-related mortality rates were significantly higher in patients with moderate to severe LVDD compared with those with mild LVDD [5 (3.3%) vs. 67 (13.6%), P < 0.05].

CONCLUSIONS

This study's findings highlight the importance of assessing the severity of LVDD in patients with DCM, which provides incremental prognostic information over LVEF.

Atrial fibrillation burden and management in cardiomyopathies: Current evidence and unmet needs

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in patients with cardiomyopathies and its clinical management presents a significant challenge. The prevalence of AF varies among cardiomyopathies, with hypertrophic (HCM) and dilated cardiomyopathy (DCM) associated with higher rates of AF. Presence of AF portends increased risk for thromboembolism, heart failure, and cardiovascular morbidity and mortality in patients with cardiomyopathy. The complex genetic substrate in DCM and non-dilated left ventricular cardiomyopathy (NDLVC) contribute to the heterogeneity of AF burden and its sequelae among cardiomyopathy genotypes, necessitating genotype-tailored approach in AF screening and management. Given the lack of validation of traditional risk scores for AF in cardiomyopathies, current clinical recommendations emphasize the importance of comprehensive risk stratification for AF, monitoring for AF, and early initiation of oral anticoagulation for brief AF episodes in specific cardiomyopathy subtypes such as hypertrophic or amyloid cardiomyopathy. AF management includes antiarrhythmic drugs, interventional therapies such as catheter ablation, mitral valve replacement when necessary, and lifestyle modifications to attenuate AF burden and improve quality of life. This review summarizes the current knowledge on the clinical significance, prognostic implications, and treatment of AF among different cardiomyopathy subtypes. We underscore the paradigm shift in AF management advocating for an individualized, subtype-specific, and genotype-aware approach to AF in cardiomyopathies, which is instrumental in improving prognosis and patient-centric care.

Assessment of Coronary Artery Disease in Non-Valvular Atrial Fibrillation: Is This Light at the End of the Tunnel?

Non-valvular atrial fibrillation (NVAF) is the most common sustained arrhythmia worldwide, and is associated with significant morbidity and mortality. Increasing life expectancy, coupled with a surge in comorbidity burden, has resulted in a sharp increase in NVAF prevalence over the last three decades. Coronary artery disease (CAD) is an important and clinically relevant risk factor of AF. Concomitant CAD has significant implications for AF management and is a major determinant of the overall outcomes. Shared risk factors, a common pathophysiological basis, and heightened thrombogenesis culminating in cardiovascular adverse events, highlight the close association between the two. The clinical course of AF is worse when associated with CAD, resulting in poor heart rate control, increased propensity to develop stroke and myocardial infarction, increased likelihood of acute presentation with hemodynamic collapse and pulmonary edema, increased bleeding tendencies, and poor response to ablation therapies. Emerging research highlighting the significant role of underlying CAD as an independent predictor of thromboembolic risk has paved the way for the adoption of CAD beyond prior myocardial infarction into the symbol "V" of the CHA2DS2-VASc score. In our opinion, elderly patients aged >65 years with AF, with a history of one or more cardiovascular comorbidities, or evidence of atherosclerosis in other vascular beds should warrant a closer look and a dedicated effort to look for associated CAD. This would allow for a more holistic and comprehensive approach to patients with AF and ultimately help reduce the disease burden and improve the overall outcomes.

Cardiac Magnetic Resonance Imaging-Derived Left Atrial Characteristics in Relation to Atrial Fibrillation Detection in Patients With an Implantable Cardioverter-Defibrillator

Background Among patients with an implantable cardioverter-defibrillator, a high prevalence of atrial fibrillation (AF) is present. Identification of AF predictors in this patient group is of clinical importance to initiate appropriate preventive therapeutic measures to reduce the risk of AF-related complications. This study assesses whether cardiac magnetic resonance imaging-derived atrial characteristics are associated with AF development in patients with a dual-chamber implantable cardioverter-defibrillator or cardiac resynchronization therapy defibrillator, as detected by the cardiac implantable electronic device. Methods and Results This single-center retrospective study included 233 patients without documented AF history at the moment of device implantation (dual-chamber implantable cardioverter-defibrillator [63.5%] or cardiac resynchronization therapy defibrillator [36.5%]). All patients underwent cardiac magnetic resonance imaging before device implantation. Cardiac magnetic resonance-derived features of left atrial (LA) remodeling were evaluated in all patients. Detection of AF episodes was based on cardiac implantable electronic device interrogation. During a median follow-up of 6.1 years, a newly diagnosed AF episode was detected in 88 of the 233 (37.8%) patients with an ICD. In these patients, increased LA volumes and impaired LA function (LA emptying fraction and LA strain) were found as compared with patients without AF during follow-up. However, a significant association was only found in patients with dilated cardiomyopathy and not in patients with ischemic cardiomyopathy. Conclusions LA remodeling characteristics were associated with development of AF in patients with dilated cardiomyopathy but not patients with ischemic cardiomyopathy, suggesting different mechanisms of AF development in ischemic cardiomyopathy and dilated cardiomyopathy. Assessment of LA remodeling before device implantation might identify high-risk patients for AF.

Clinical Utility and Validation of the Krakow DCM Risk Score—A Prognostic Model Dedicated to Dilated Cardiomyopathy

Background: One of the most common causes of heart failure is dilated cardiomyopathy (DCM). In DCM, the mortality risk is high and reaches approximately 20% in 5 years. A patient’s prognosis should be established for appropriate HF management. However, so far, no validated tools have been available for the DCM population. Methods: The study population consisted of 735 DCM patients: 406 from the derivation cohort (previously described) and 329 from the validation cohort (from 2009 to 2020, with outcome data after a mean of 42 months). For each DCM patient, the individual mortality risk was calculated based on the Krakow DCM Risk Score. Results: During follow-up, 49 (15%) patients of the validation cohort died. They had shown significantly higher calculated 1-to-5-year mortality risks. The Krakow DCM Risk Score yielded good discrimination in terms of overall mortality risk, with an AUC of 0.704–0.765. Based on a 2-year mortality risk, patients were divided into non-high (≤6%) and high (>6%) mortality risk groups. The observed mortality rates were 8.3% (n = 44) vs. 42.6% (n = 75), respectively (HR 3.37; 95%CI 1.88–6.05; p < 0.0001). Conclusions: The Krakow DCM Risk Score was found to have good predictive accuracy. The 2-year mortality risk > 6% has good discrimination for the identification of high-risk patients and can be applied in everyday practice.

Determinants of Prolonged Length of Hospital Stay of Patients with Atrial Fibrillation

Background and Aim: The increasing prevalence and high hospitalization rates make atrial fibrillation (AF) a significant healthcare strain. However, there are limited data regarding the length of hospital stay (LOS) of AF patients. Our purpose was to determine the main drivers of extended LOS of AF patients. Methods: All AF patients, hospitalized consecutively in a tertiary cardiology center, from January 2018 to February 2020 were included in this retrospective cohort study. Readmissions were excluded. Prolonged LOS was defined as more than seven days (the upper limit of the third quartile). Results: Our study included 949 AF patients, 52.9% females. The mean age was 72.5 ± 10.3 years. The median LOS was 4 days. A total of 28.7% had an extended LOS. Further, 82.9% patients had heart failure (HF). In multivariable analysis, the independent predictors of extended LOS were: acute coronary syndromes (ACS) (HR 4.60, 95% CI 1.66–12.69), infections (HR 2.61, 95% CI 1.44–3.23), NT-proBNP > 1986 ng/mL (HR 1.96, 95% CI 1.37–2.82), acute decompensated HF (ADHF) (HR 1.76, 95% CI 1.23–2.51), HF with reduced ejection fraction (HFrEF) (HR 1.69, 95% CI 1.15–2.47) and the HAS-BLED score (HR 1.42, 95% CI 1.14–1.78). Conclusion: ACS, ADHF, HFrEF, increased NT-proBNP levels, infections and elevated HAS-BLED were independent predictors of extended LOS, while specific clinical or therapeutical AF characteristics were not.

Relationships between Pulmonary Hypertension Risk, Clinical Profiles, and Outcomes in Dilated Cardiomyopathy

Pulmonary hypertension (PH) in patients with heart failure (HF) contributes to a poorer prognosis. However, in those with dilated cardiomyopathy (DCM), the true prevalence and role of PH is unclear. Therefore, this study aimed to analyze the profile of DCM patients at various levels of PH risk, determined via echocardiography, and its impact on outcomes. The 502 DCM in- and out-patient records were retrospectively analyzed. Information on patient status was gathered after 45.9 ± 31.3 months. Patients were divided into 3 PH-risk groups based on results from echocardiography measurements: low (L, n = 239, 47.6%), intermediate (I, n = 153, 30.5%), and high (H, n = 110, 21.9%). Symptom duration, atrial fibrillation, ventricular tachyarrhythmia, ejection fraction, right atrial area, and moderate or severe mitral regurgitation were found to be independently associated with PH risk. During the follow-up period, 83 (16.5%) DCM patients died: 29 (12.1%) in L, 31 (20.3%) in I, and 23 (20.9%) in H. L-patients had a significantly lower risk of all-cause death (L to H: HR 0.55 (95%CI 0.32–0.98), p = 0.01), while no differences in prognosis were found between I and H. In conclusion, over one in five DCM patients had a high PH risk, and low PH risk was associated with better prognoses.