Tachycardiomyopathy in Patients without Underlying Structural Heart Disease

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Anti-arrhythmic drugs in atrial fibrillation: tailor-made treatments

During the last decades, many improvements have been made regarding the treatment of atrial fibrillation in terms of risk prevention, anti-coagulation strategies, and gain in quality of life. Among those, anti-arrhythmic drugs (AADs) have progressively fallen behind and overtaken by technological aspects as devices as procedures are now the standards of care for many patients. But is this it? Are AADs doomed to be relegated to an obscure and rarely read paragraph of the European recommendations? Or could they be still employed safely and effectively? In the present paper, we will discuss contemporary evidence in order to define where AADs still play a pivotal role, how should AADs be used, and whether a tailored approach can be the way to propose the right treatment to the right patient.

Cost-effectiveness analysis of cardiac implantable electronic devices with reactive atrial-based antitachycardia pacing

AIMS

Reactive atrial-based anti-tachycardia pacing (rATP) in pacemakers (PMs) and cardiac resynchronization therapy defibrillators (CRT-Ds) has been reported to prevent progression of atrial fibrillation, and this reduced progression is expected to decrease the risk of complications such as stroke and heart failure (HF). This study aimed to assess the cost-effectiveness of rATP in PMs and CRT-Ds in the Japanese public health insurance system.

METHODS AND RESULTS

We developed a Markov model comprising five states: bradycardia, post-stroke, mild HF, severe HF, and death. For devices with rATP and control devices without rATP, we compared the incremental cost-effectiveness ratio (ICER) from the payer's perspective. Costs were estimated from healthcare resource utilisation data in a Japanese claims database. We evaluated model uncertainty by analysing two scenarios for each device. The ICER was 763 729 JPY/QALY (5616 EUR/QALY) for PMs and 1,393 280 JPY/QALY (10 245 EUR/QALY) for CRT-Ds. In all scenarios, ICERs were below 5 million JPY/QALY (36 765 EUR/QALY), supporting robustness of the results.

CONCLUSION

According to a willingness to pay threshold of 5 million JPY/QALY, the devices with rATP were cost-effective compared with control devices without rATP, showing that the higher reimbursement price of the functional categories with rATP is justified from a healthcare economic perspective.

Rate of atrial fibrillation and flutter induced tachycardiomyopathy in a cohort of hospitalized patients with heart failure and detection of indicators for improved diagnosis

Background

Atrial fibrillation (AF) and atrial flutter (AFL) induced tachycardiomyopathy (TCM) has been known to cause reversible heart failure (HF) for many years. However, the prevalence of the disease is unknown, and diagnosis is challenging. Therefore, the aim of the present study was (1) to assess the rate of AF/AFL induced TCM and (2) to identify indicators for diagnosis.

Methods

Consecutively, all patients with a diagnosis of HF who were hospitalized in our department within 12 months were reviewed. For the main analysis, all patients with HF with reduced ejection fraction (HFrEF) and AF or AFL were included. AF/AFL induced TCM was diagnosed when there was at least a 10% improvement in left ventricular ejection fraction under rhythm or rate control within 3 months. Patients with HFrEF with AF/AFL but without TCM served as control group.

Results

A total of 480 patients were included. AF/AFL induced TCM occurred in 26 patients (5.4%) and HFrEF with AF/AFL in 53 patients (11%). Independent indicators of AF/AFL induced TCM were age<79 years [Odds ratio 5.887, confidence interval (CI) 1.999-17.339, p < 0.001], NT-pro-BNP <5,419 pg/mL (Odds ratio 2.327, CI 1.141-4.746, p = 0.004), and a resting heart rate >112 bpm (Odds ratio 2.503, CI 1.288-4.864, p = 0.001).

Conclusion

Approximately 5% of all patients hospitalized for HF suffer from AF/AFL induced TCM. Improved discrimination of AF/AFL induced TCM to HFrEF with AF/AFL is possible considering age, NT-pro-BNP level, and resting heart rate >112 beats/minute. Based on these parameters, an earlier diagnosis and improved therapy might be possible.

Predictors of tachycardia-induced cardiomyopathy in patients with first-time decompensation of chro­nic heart failure with reduced left ventricular ejection fraction of nonischemic etiology and persistent atrial tachyarrhythmia

Aim    To identify possible predictors of tachycardia-induced cardiomyopathy (TICMP) in patients with newly developed decompensated chronic heart failure (CHF) of nonischemic origin with reduced left ventricular ejection fraction (LV EF) and with persistent atrial tachyarrhythmias. Material and methods    This study included 88 patients with newly developed decompensated CHF of nonischemic origin with reduced LV EF and persistent atrial tachyarrhythmias. Resting 12-lead electrocardiography (EGC) and transthoracic echocardiography (EchoCG) were performed upon admission and following the electrical impulse therapy for all patients. Also, 24-h ECG monitoring was performed to confirm sinus rhythm stability. After recovery of sinus rhythm, outpatient monitoring was performed for three months, including repeated EchoCG to evaluate the dynamics of heart chamber dimensions and LV EF. Results    The patients were divided into two groups based on the increase in LV EF: 68 responders (TICMP patients with a LV EF increase by >10%) and 20 non-responders (patients with an increase in LV EF by <10% during 3 months following the sinus rhythm recovery). According to results of the baseline EchoCG, LV EF did not significantly differ in the two subgroups (TICMP, 40±8.3 %, 18–50 % and non-responders, 38.55±7.9 %, 24–50 %); moreover, the incidence of cases with LV EF <30% did not differ either (9 patients TICMP and 2 non-responders, р=1.0). TICMP patients compared to non-responders, had significantly smaller left atrial dimensions (4.53±1.14 (2–7) cm and 5.68±1.41 (4–8) cm, р=0.034; 80.8±28.9 (27–215) ml and 117.8±41.3 (46–230) ml, р=0.03, respectively) and left ventricular end-systolic volume (ESV) (67.7±33.1 (29–140) ml and 104.5±44.7 (26–172) ml, р=0.02, respectively). The effect of major EchoCG parameters on the probability of TICMP development was assessed by one-factor and multifactor regression analyses with adjustments for age and sex. The probability of TICMP increased with the following baseline EchoCG parameters: end-diastolic volume (EDV) <174 ml [odd ratio (OR), 0.115, 95 % confidence interval (CI): 0.035–0.371], ESV <127 ml [OR, 0.034, 95 % CI: 0.007–0.181], left atrial volume <96 ml [OR, 0.08 , 95 % CI: 0.023–0.274], right ventricular dimension <4 cm [OR, 0.042 , 95 % CI: 0.005–0.389].Conclusion    Among patients with newly developed decompensation of CHF with reduced LV EF of non-ischemic origin and persistent atrial arrhythmias, TICMP was detected in 72 % of patients. The probability of TICMP did not depend on baseline EF and duration of arrhythmias, but increased with the following baseline EchoCG parameters: EDV< 174 ml, ESV< 127 ml, left atrial volume <96 ml, right ventricular dimension <4 cm. The multifactorial analysis showed that a right atrial volume <96 ml is an independent predictor for the development of TICMP.

Atrial fibrillation-induced tachycardiomyopathy and heart failure: an underappreciated and elusive condition

Many patients with persistent, chronic, or frequently recurring paroxysmal atrial fibrillation (AF) may develop a tachycardiomyopathy (TCM) with left ventricular (LV) dysfunction and heart failure (HF), which is reversible upon restoration and maintenance of sinus rhythm, when feasible, or via better and tighter ventricular rate (VR) control. Mechanisms involved in producing this leading cause of TCM (AF-TCM) include loss of atrial contraction, irregular heart rate, fast VR, neurohumoral activation, and structural myocardial changes. The most important of all mechanisms relates to optimal VR control, which seems to be an elusive target. Uncontrolled AF may also worsen preexisting LV dysfunction and exacerbate HF symptoms. Data, albeit less robust, also point to deleterious effects of slow VRs on LV function. Thus, a J-shaped relationship between VR and clinical outcome has been suggested, with the optimal VR control hovering at ~ 65 bpm, ranging between 60 and 80 bpm; VRs above and below this range may confer higher morbidity and mortality rates. A convergence of recent guidelines is noted towards a stricter rather than a more lenient VR control with target heart rate < 80 bpm at rest and < 110 bpm during moderate exercise which seems to prevent TCM or improve LV function and exercise capacity and relieve TCM-related symptoms and signs. Of course, restoring and maintaining sinus rhythm is always a most desirable target, when feasible, either with drugs or more likely with ablation. All these issues are herein reviewed, current guidelines are discussed and relevant data are tabulated and pictorially illustrated.

Left Ventricular Systolic Dysfunction Due to Atrial Fibrillation: Clinical and Echocardiographic Predictors

Background: Diagnosis of AF-induced cardiomyopathy can be challenging and relies on ruling out other causes of cardiomyopathy and, after restoration of sinus rhythm, recovery of left ventricular (LV) function. The aim of this study was to identify clinical and echocardiographic predictors for developing cardiomyopathy with systolic dysfunction in patients with atrial tachyarrhythmia. Methods: This retrospective study was conducted in a large tertiary care centre and compared patients who experienced deterioration of LV ejection fraction (EF) during paroxysmal AF, demonstrated by precardioversion transoesophageal echocardiography with patients with preserved LV function during AF. All patients had documented preserved LVEF at baseline (EF >50%) while in sinus rhythm. Results: Of 482 patients included in the final analysis, 80 (17%) had reduced and 402 (83%) had preserved LV function during the precardioversion transoesophageal echocardiography. Patients with reduced LVEF were more likely to be men and to have a more rapid ventricular response during AF or atrial flutter (AFL). A history of prosthetic valves was also identified as a risk factor for reduced LVEF. Patients with reduced LVEF also had higher incidence of tricuspid regurgitation and right ventricular dysfunction. Conclusion: In ‘real-world’ experience, male patients with rapid ventricular response during paroxysmal AF or AFL are more prone to LVEF reduction. Patients with prosthetic valves are also at risk for LVEF reduction during AF/AFL. Finally, tricuspid regurgitation and right ventricular dysfunction may indicate relatively long-standing AF with an associated reduction in LVEF.

Timely-Automatic Procedure for Estimating the Endocardial Limits of the Left Ventricle Assessed Echocardiographically in Clinical Practice

In this paper, we propose an analytical rapid method to estimate the endocardial borders of the left ventricular walls on echocardiographic images for prospective clinical integration. The procedure was created as a diagnostic support tool for the clinician and it is based on the use of the anisotropic generalized Hough transform. Its application is guided by a Gabor-like filtering for the approximate delimitation of the region of interest without the need for computing further anatomical characteristics. The algorithm is applying directly a deformable template on the predetermined filtered region and therefore it is responsive and straightforward implementable. For accuracy considerations, we have employed a support vector machine classifier to determine the confidence level of the automated marking. The clinical tests were performed at the Cardiology Clinic of the County Emergency Hospital Timisoara and they improved the physicians perception in more than 50% of the cases. The report is concluded with medical discussions.