Theophylline use-a conundrum in modern medicine: a case report.

Atrial fibrillation (AF) with rapid ventricular response (RVR) is a prevalent condition among critically ill patients, frequently contributing to haemodynamic instability. However, the association between AF with RVR and hospital mortality in critically ill patients remains inconclusive. To investigate the associations between AF with RVR and hospital mortality in patients admitted to the intensive care unit (ICU). This study included patients from the MIMIC-IV database who experienced episodes of atrial fibrillation (AF) during their ICU stay. AF with RVR was defined as a heart rate (HR) >110 beats/min (bpm) during an episode of AF and was further classified into three categories: mild (111-130 bpm), moderate (131-150 bpm) and severe (>150 bpm) RVR. Multivariable adjusted logistic regression models and restricted cubic spline analyses were used to estimate odds ratios and 95% CIs and to explore linear and non-linear relationships of RVR and mortality, respectively. A total of 7027 eligible patients with AF were identified, and AF with RVR occurred in 5274 patients (75.1%). Patients with RVR had a significantly higher hospital mortality compared to those without (23.8% vs. 15.8%, adjusted OR, 1.32; 95% CI (1.13-1.54), p < .001). The adjusted ORs in mild, moderate and severe RVR were 1.11 (0.93-1.33), 1.25 (1.05-1.49) and 1.87 (1.54-2.27) for hospital mortality (p for trend <.001), respectively. Restricted cubic spline analyses showed a non-linear relationship of RVR with hospital mortality (p < .001). Additionally, hospital mortality decreased linearly with the reduction in 1-h HR following moderate and severe RVR. AF with moderate and severe RVR was associated with increased hospital mortality in critically ill patients, and acute HR reduction following moderate and severe RVR may be beneficial in reducing hospital mortality. This study emphasized the importance of individual management of AF patients in the ICU according to the severity of RVR and provided an approximate range of RVR to guide risk stratification.

Information about a real patient is presented in stages (boldface type) to expert clinicians (Dr James M

A 62-year-old woman with hypertension presented with progressively worsening shortness of breath due to acute decompensated heart failure with atrial fibrillation in rapid ventricular response. During admission, she was managed with diuretics, goal-directed medical therapy for heart failure with successful DCCV (Direct current cardioversion) for first episode atrial fibrillation. However, one day after discharge, the patient presented with a recurrence of dyspnea with atrial fibrillation in rapid ventricular response and a reduction in urine output with elevated serum creatinine. In this case report, we describe the syndrome of acute kidney injury following cardioversion for atrial fibrillation known as AFCARD (Atrial Fibrillation Cardioversion Associated with Renal Dysfunction), highlight its incidence and reflect on renal dysfunction subserving the recurrence of atrial fibrillation after successful DCCV.

We present a unique case of a 60-year-old male with congestive heart failure who was admitted for a pre-syncopal episode and found to be in atrial fibrillation with rapid ventricular response (RVR). In order to effectively rate control the patient, he was administered an amiodarone bolus and intravenous (IV) infusion over 24 hours, along with a single oral 200 mg dose the following day. The patient subsequently developed acute hepatotoxicity along with features of acute kidney injury (AKI), pulmonary distress, and leukocytosis. After ruling out other etiologies for acute liver, pulmonary, and kidney injury, amiodarone-induced multi-organ toxicity was suspected and amiodarone was discontinued. Within hours of amiodarone discontinuation, the patient’s clinical status and organ function improved remarkably. In the setting of a patient being treated with IV amiodarone and presenting with sudden signs of dyspnea, acute elevation of transaminases and AKI within one to two days of initial dosing, acute amiodarone-induced organ toxicity should be considered.

Although evaluation of left ventricular ejection fraction (LVEF) is crucial for deciding the rate control strategy in patients with atrial fibrillation (AF), real-time assessment of LVEF is limited in outpatient settings. We aimed to investigate the performance of artificial intelligence-based algorithms in predicting LV systolic dysfunction (LVSD) in patients with AF and rapid ventricular response (RVR). This study is an external validation of a pre-existing deep learning algorithm based on residual neural network architecture. Data were obtained from a prospective cohort of AF with RVR at a single centre between 2018 and 2023. Primary outcome was the detection of LVSD, defined as a LVEF ≤ 40%, assessed using 12-lead electrocardiography (ECG). Secondary outcome involved predicting LVSD using 1-lead ECG (Lead I). Among 423 patients, 241 with available echocardiography data within 2 months were evaluated, of whom 54 (22.4%) were confirmed to have LVSD. Deep learning algorithm demonstrated fair performance in predicting LVSD [area under the curve (AUC) 0.78]. Negative predictive value for excluding LVSD was 0.88. Deep learning algorithm resulted competent performance in predicting LVSD compared with N-terminal prohormone of brain natriuretic peptide (AUC 0.78 vs. 0.70, P = 0.12). Predictive performance of the deep learning algorithm was lower in Lead I (AUC 0.68); however, negative predictive value remained consistent (0.88). Deep learning algorithm demonstrated competent performance in predicting LVSD in patients with AF and RVR. In outpatient setting, use of artificial intelligence-based algorithm may facilitate prediction of LVSD and earlier choice of drug, enabling better symptom control in AF patients with RVR.

Atrial fibrillation with rapid ventricular response as a maternal presentation of mirror syndrome: a case report.

Painless thyroiditis is a variant of thyroiditis without the typical neck pain and is otherwise similar to subacute thyroiditis, which is a known post-viral condition and has been associated with coronavirus disease 2019 (COVID-19) infections. While it is usually self-limiting, it can lead to thyrotoxicosis that can predispose individuals to cardiac dysrhythmias, including atrial fibrillation. There has been a clear association between COVID-19 and subacute thyroiditis with a few case reports describing atrial fibrillation. We present a case of a healthy patient with new-onset atrial fibrillation secondary to painless thyroiditis. This report highlights the rare entity of painless thyroiditis leading to atrial fibrillation with rapid ventricular response in a patient who recently recovered from COVID-19. Physicians should consider the potential association of painless thyroiditis in patients with new-onset atrial fibrillation who recently recovered from COVID-19.

Background Cardiac resynchronization therapy (CRT) is an option for treatment for chronic heart failure (HF) associated with left bundle branch block (LBBB). Patients with HF and right bundle branch block (RBBB) have potentially worse outcomes in comparison to LBBB. Traditional CRT in RBBB can increase mortality and HF deterioration rates over native disease progression. His bundle pacing may improve the results of CRT in those patients. Furthermore, atrioventricular node ablation (AVNA) for rate control in atrial fibrillation (AF) can be challenging in patients with previously implanted leads in His region.Case summary We report the case of 74-year-old gentleman with a 5-year history of HF, permanent AF with a rapid ventricular response, and RBBB. He was admitted to the hospital with complaints of severe weakness and shortness of breath. Left ventricular ejection fraction (LVEF) was decreased (41%), right ventricle (RV) was dilated (41 mm), and QRS was prolonged (200 ms) with RBBB morphology. The patient underwent His-optimized CRT with further left-sided AVNA. As a result, LVEF increased to 51%, RV dimensions decreased to 35 mm with an improvement of the clinical status during a 6-month follow-up.Discussion Patients with AF, RBBB, and HF represent the least evaluated clinical subgroup of individuals with less beneficial clinical outcomes according to CRT studies. Achieving the most effective resynchronization could require pacing fusion from sites beyond traditional with the intention to recruit intrinsic conduction pathways. This approach can be favourable for reducing RV dilatation, improving LVEF, and maximizing electrical resynchronization.

Disclosure: R. Devbhandari: None. S. Tripathee: None. H. Akbari: None. M. Shah: None. A. Kang: None. R.M. Jhingan: None.Introduction: Amiodarone, a potent antiarrhythmic, is highly effective for rate control in atrial fibrillation (AF), particularly in hemodynamically unstable patients. Amiodarone-induced thyrotoxicosis occurs in 3-10% of cases due to iodine-induced hormone synthesis and follicular cell toxicity. We report a case of thyroid storm with AF, where thyroid function improved despite IV amiodarone use. Case report 34-year-old non-verbal male with Friedreich’s ataxia, quadriplegia, and paroxysmal AF presented with tachycardia and fever. On arrival, he was tachycardic with low normal blood pressure. The electrocardiogram showed atrial fibrillation. Initial labs were unremarkable. Computed tomography (CT) scan didn’t reveal any pulmonary embolism or cardiopulmonary abnormalities but raised suspicion for cholecystitis. He soon developed AF with rapid ventricular response with heart rates 200-250 bpm, refractory to IV metoprolol, and two rounds of synchronized cardioversion. He was started on IV esmolol and digoxin. Due to persistent tachycardia and hypotension precluding diltiazem use, an IV amiodarone drip was started as per cardiology recommendation. Phenylephrine was started for inotropy due to its negative chronotropic effect. The thyroid function panel revealed TSH <0.01 mIU/L (0.35-4.94), FT4 2.82 ng/dL (0.7-1.48), and T3 53.17 ng/dL (35-193). He had no prior history of thyroid disorders and CT imaging showed no thyroid abnormalities. He was suspected to have new onset hyperthyroidism with thyrotoxicosis. He subsequently developed septic shock secondary to acute acalculous cholecystitis confirmed on a hepatobiliary iminodiacetic acid scan. Echocardiography was unremarkable. Thyroid storm was suspected in the setting of acute cholecystitis and a Burch-Wartofsky score of 65. He was treated with IV hydrocortisone, oral methimazole, IV fluids, and antibiotics which along with percutaneous cholecystostomy led to hemodynamic improvement. Hydrocortisone was tapered with the continual improvement of FT4, and methimazole was continued for new-onset hyperthyroidism, with outpatient follow-up planned for further workup. Conclusion: This case highlights the potential use of IV amiodarone in thyroid storm for refractory arrhythmia despite maximal conventional management without worsening of thyrotoxicosis, as the patient’s thyrotoxic symptoms and thyroid function improved despite IV amiodarone. IV amiodarone inhibits peripheral T4 to T3 conversion which in combination with anti-thyroid medications, preferably started before amiodarone to suppress new hormone synthesis, may help control thyrotoxicosis symptoms in the short term. However, data remain limited due to the absence of randomized controlled trials and their known thyrotoxic properties, for which further investigation is warranted.Presentation: Sunday, July 13, 2025

Introduction Data suggest inappropriate defibrillator shocks are associated with a higher risk of all-cause mortality, particularly those delivered for atrial fibrillation (AF). However, the impact of inappropriate shocks has not been studied specifically in a population with AF. Aims to determine if AF-triggered inappropriate shocks are associated with long- term mortality in patients with AF and defibrillators implanted for primary prevention. Methods Retrospective single-center study. We analyzed all patients with defibrillators implanted for primary prevention in whom AF was diagnosed until the end of 2017. The cause of inappropriate shocks was evaluated by analysis of the stored intracardiac electrogram. Basal characteristics, cardiovascular risk factors, left ventricle ejection fraction, heart failure etiology (ischemic and non-ischemic), kidney function (creatinine) and medication were evaluated. Death was assessed during the follow-up. Results We studied 177 patients [median age 66 years (IQR 59-71); 82% male], with defibrillators and AF. AF was diagnosed before defibrillator implantation in 131 patients (74%) and after the implantation in the remaining 46 (26%). Inappropriate shocks occurred in 31 patients and 24 (14%) were caused by AF with rapid ventricular response: 13 patients with previously diagnosed AF and 11 with new-onset AF. During a median follow-up of 65 (IQR: 36-104) months, 74 patients died. Multivariate Cox-regression analysis demonstrated inappropriate shocks caused by AF were not independently related with death (adjusted HR 0.53; CI 0.23-1.23, p = 0.14). Kaplan-Meier survival curve demonstrated patients with AF-triggered inappropriate shocks had a better survival comparing to those with AF but without inappropriate shocks (logrank, p = 0.03) (figure). Conclusions In this group of AF patients, inappropriate shocks caused by AF did not increase the risk of death. Instead, these patients had a better survival comparing to those with AF but no shocks, probably due to a re-evaluation of the patient´s status and subsequent closer medical monitoring, strictly control of symptoms and optimization of drug treatment. These results demonstrate that inappropriate shocks are probably not deleterious per si through a direct mechanism. Abstract Figure. Kaplan-Meier survival curve

BRASH SYNDROME: A DOWNWARD SPIRAL

Intravenous magnesium (IV Mg), a commonly utilized therapeutic agent in the management of atrial fibrillation (AF) with rapid ventricular response, is thought to exert its influence via its effect on cellular automaticity and prolongation of atrial and atrioventricular nodal refractoriness thus reducing ventricular rate. We sought to undertake a systematic review and meta-analysis of the effectiveness of IV Mg versus placebo in addition to standard pharmacotherapy in the rate and rhythm control of AF in the nonpostoperative patient cohort given that randomized control trials (RCTs) have shown conflicting results. Randomized controlled trials comparing IV Mg versus placebo in addition to standard of care were identified via electronic database searches. Nine RCTs were returned with a total of 1048 patients. Primary efficacy endpoints were study-defined rate control and rhythm control/reversion to sinus rhythm. The secondary endpoint was patient experienced side effects. Our analysis found IV Mg in addition to standard care was successful in achieving rate control (odd ratio [OR] 1.87, 95% confidence interval [CI] 1.13-3.11, p = .02) and rhythm control (OR 1.45, 95% CI 1.04-2.03, p = .03). Although not well reported among studies, there was no significant difference between groups regarding the likelihood of experiencing side effects. IV Mg, in addition to standard-of-care pharmacotherapy, increases the rates of successful rate and rhythm control in nonpostoperative patients with AF with rapid ventricular response and is well tolerated.

Acute heart failure (AHF) patients are commonly encountered in intensive care units (ICUs) and their managements are challenging to intensivists. Atrial fibrillation (AF) is one of the most common cardiac rhythms among patients of AHF. It is estimated that 20% to 30% of AHF patients have rapid AF during acute stage of hospital admission. The relationship between AHF and AF is complex in the sense that they interact with each other. Acute heart failure will cause rapid AF, and rapid AF may in turn precipitate AHF. When the above 2 conditions present together, the morbidity and mortality of patients will increase, attributable to both the underlying disease condition and from the therapy used. Intensivists taking care of AHF patients with rapid AF should carefully evaluate the patient and consider 3 different situations: 1. Patients with newly onset acute heart failure with newly onset AF; 2. Patients of chronic heart failure with newly onset AF; and 3. Patients of decompensated chronic heart failure with chronic AF and rapid ventricular response. Other considerations which will influence the treatment strategy include: 1. Is the patient's baseline left ventricular systolic function preserved or reduced? 2. What is the duration of the AF episode? 3. Is the patient already treated with antiarrhythmic drugs for rhythm control or using only rate control agents, with or without anticoagulation? 4. What comorbidities are present? In this article management strategies according to different clinical scenarios will be discussed.

Introduction: Diclofenac sodium is a widely used medication for its analgesic and anti-inflammatory properties. Although the adverse effects of diclofenac are well described, diclofenac-associated new-onset atrial fibrillation in a young, healthy adult has not been previously reported. Case Report: A 22-year-old man with severe pain following an ankle injury used diclofenac sodium at a dose of 50 mg orally three times daily for one week. At the end of the week, he presented to the emergency department (ED) complaining of palpitations for a few hours. The patient had no past medical history. His physical examination revealed no pathologic signs except for tachycardia and an irregularly irregular pulse rate. An electrocardiogram showed an irregularly irregular rhythm with a ventricular rate of 128 beats per minute (bpm) (rapid ventricular response) and absent P waves, consistent with atrial fibrillation. The patient was monitored in the ED, and a standard regimen of intravenous amiodarone was initiated for rate control. Approximately three hours after initiation, sinus rhythm returned and his heart rate stabilized at 60 bpm. Conclusion: This case report describes a possible association between diclofenac use and new-onset atrial fibrillation in a young, previously healthy individual. The findings highlight the need for awareness of the potential arrhythmogenic effects of diclofenac and underscore the importance of taking a careful drug history in patients presenting with unexplained atrial fibrillation.

Metoclopramide and Digoxin Cause 22 Episodes of Bradyarrhythmias