Determinants of left atrium thrombi in scheduled cardioversion: an ENSURE-AF study analysis

Jose L Merino1, Gregory Y H Lip2,3, Hein Heidbuchel4

  • 1Arrhythmia and Robotic Electrophysiology Unit, Hospital Universitario La Paz, IDIPaz, Departamento de Medicina de la Universidad Autonoma de Madrid, P. Castellana, 261 (H. Gral, 1st Floor), Madrid, Spain.

Insights

Left atrial thrombi (LAT) detected by transesophageal echocardiography (TOE) frequently defer cardioversion in atrial fibrillation (AF) patients. Advanced age (≥75 years) and heart failure are key predictors of LAT presence.

Area of Science:

  • Cardiology
  • Clinical Trials
  • Echocardiography

Background:

  • Atrial fibrillation (AF) necessitates cardioversion, often preceded by transesophageal echocardiography (TOE) to detect left atrial thrombi (LAT).
  • The ENSURE-AF trial provided a large dataset for analyzing factors associated with LAT before electrical cardioversion (ECV).

Purpose of the Study:

  • To identify determinants of TOE-detected LAT in patients with non-valvular AF scheduled for ECV.
  • To understand factors contributing to the cancellation or deferral of ECV due to LAT.

Main Methods:

  • Ancillary analysis of the ENSURE-AF prospective randomized clinical trial data.
  • Stratification of 1183 patients by TOE use, with analysis of univariate and logistic regression for LAT predictors.

Main Results:

  • Left atrial thrombi (LAT) were detected in 8.2% of patients undergoing TOE prior to ECV.
  • Univariate analysis showed age ≥75 years, lower weight, lower creatinine clearance, heart failure, and diuretic use were more prevalent in the LAT group.
  • Logistic regression identified age (P=0.0202) and heart failure (P=0.0064) as independent predictors of LAT.

Conclusions:

  • Elective ECV is frequently postponed due to TOE-detected LAT in non-valvular AF patients.
  • Age ≥75 years and the presence of heart failure are significantly associated with LAT.
  • These findings highlight the importance of pre-cardioversion assessment for LAT in specific patient subgroups.
Abstract

Related Concept Videos

Reinforcement Schedules01:24

Reinforcement Schedules

Positive reinforcement is a powerful method for teaching new behaviors to both animals and humans. B.F. Skinner demonstrated this with his experiments using rats in a Skinner box. When a rat pressed a lever, it received a food pellet. This immediate reward encouraged the rat to repeat the behavior. This method, where a reward follows every instance of the behavior, is known as continuous reinforcement. It is highly effective for establishing new behaviors quickly.
Once a behavior is learned,...
469
Determining Order of Reaction02:53

Determining Order of Reaction

Rate laws describe the relationship between the rate of a chemical reaction and the concentration of its reactants. In a rate law, the rate constant k and the reaction orders are determined experimentally by observing how the rate of reaction changes as the concentrations of the reactants are changed. A common experimental approach to the determination of rate laws is the method of initial rates. This method involves measuring reaction rates for multiple experimental trials carried out using...
61.8K
Determination01:51

Determination

During embryogenesis, cells become progressively committed to different fates through a two-step process: specification followed by determination. Specification is demonstrated by removing a segment of an early embryo, “neutrally” culturing the tissue in vitro—for example, in a petri dish with simple medium—and then observing the derivatives. If the cultured region gives rise to cell types that it would normally generate in the embryo, this means that it is specified. In...
20.8K
Determining the pH of Salt Solutions04:08

Determining the pH of Salt Solutions

The pH of a salt solution is determined by its component anions and cations. Salts that contain pH-neutral anions and the hydronium ion-producing cations form a solution with a pH less than 7. For example, in ammonium nitrate (NH4NO3) solution, NO3− ions do not react with water whereas NH4+ ions produce the hydronium ions resulting in the acidic solution.  In contrast, salts that contain pH-neutral cations and the hydroxide ion-producing anions form a solution with a pH greater than 7. For...
46.9K
Rate-Determining Steps03:08

Rate-Determining Steps

Relating Reaction Mechanisms
In a multistep reaction mechanism, one of the elementary steps progresses significantly slower than the others. This slowest step is called the rate-limiting step (or rate-determining step). A reaction cannot proceed faster than its slowest step, and hence, the rate-determining step limits the overall reaction rate.
The concept of rate-determining step can be understood from the analogy of a 4-lane freeway with a short-stretch of traffic-bottleneck caused due to...
36.8K
Experimental Determination of Chemical Formula02:37

Experimental Determination of Chemical Formula

The elemental makeup of a compound defines its chemical identity, and chemical formulas are the most concise way of representing this elemental makeup. When a compound’s formula is unknown, measuring the mass of its constituent elements is often the first step in determining the formula experimentally.
46.4K