A comprehensive review of atrial fibrillation

In the US, atrial fibrillation (AF), a heart condition that causes an irregular heartbeat in the upper chambers of the heart, affects up to one in three people in their lifetime. Significant complications associated with this condition include ischemic stroke, heart failure, myocardial infarction, chronic kidney disease, dementia, and mortality.

In a new overview article in the Journal of the American Medical Associationresearchers from Boston University Chobanian & Avedisian School of Medicine and Boston Medical Center summarize current evidence regarding the epidemiology, pathophysiology, diagnosis, and treatment of AF.

Given the increasing incidence, prevalence, and lifelong risks of AF, it is imperative that we promote the most effective protocols to help reduce risk factors and prevent the onset, recurrence, and complications of AF in our patients.”

Emelia J. Benjamin, MD, ScM, FACC, FAHA, the Jay and Louise Coffman Professor of Vascular Medicine and professor of cardiovascular medicine at the school and cardiologist at Boston Medical Center (BMC)

The researchers conducted a PubMed search for English-language articles published between January 1990 and August 15, 2024, on the epidemiology, pathophysiology, clinical presentation, prognosis, and treatment of AF.

Their results include insights into the epidemiology, pathophysiology, screening and detection, clinical presentation and treatment of atrial fibrillation.

In terms of epidemiology, between 1990 and 2024, the age-adjusted incidence per 1,000 person-years increased from 3.7 to 13.4 in men and from 2.5 to 8.6 in women, and the prevalence from 20.4 to 96. 2 in men and from 13.7 to 49.4 in women. The highest prevalence was observed in high-income countries in North America, Australia and Asia-Western Europe. The global prevalence was higher in men (about 28 million) versus women (about 25 million). Furthermore, older age was associated with a higher incidence of atrial fibrillation. The authors also noted that more research is needed to address health disparities in AF outcomes among individuals from minority races and ethnicities, or from lower socioeconomic backgrounds.

Regarding pathophysiology, the researchers observed that diseases such as hypertension, obesity, and valvular heart disease (such as mitral valve stenosis and mitral valve regurgitation) were associated with atrial pathology and AF.

For the screening and detection of atrial fibrillation, they noted that the probability of detection increased with the duration of electrocardiogram (ECG) monitoring, but experts are uncertain about the benefits of screening for AF in the general population to detect asymptomatic AF. An implantable loop recorder (ILR) (a subcutaneous device that continuously monitors heart rhythm for about four years) found that AF was diagnosed in a third of patients, while in the Apple Heart Study only 34% of those who received the smartwatch notification for received atrial arrhythmias was diagnosed. fibrillation was then diagnosed with AF using ECG patch monitoring.

In terms of clinical presentation, the researchers found that typical symptoms of AF include palpitations with or without labored breathing, chest pain, presyncope (remaining conscious while feeling like you are about to pass out), exercise intolerance, and fatigue include. Asymptomatic initial presentation of AF was more common in men (10% in men vs. 3% in women) and older adults (74 years vs. 62 years for symptomatic people). Diabetes was more common in people with asymptomatic AF.

Regarding the treatment of AF, the recommended initial treatment of patients at risk for AF (stage 1 or 2) or with AF (stage 3 or 4) consisted of lifestyle modification and risk factors, such as weight loss, exercise, targeted control of blood pressure, quitting smoking and limiting alcohol intake. “Consensus opinion is now moving toward early intervention for AF to favorably impact outcomes. Technological advances in catheter ablation have made this an attractive option for many patients,” said senior author Robert Helm, MD, FHRS, assistant professor of medicine at the school and a clinical electrophysiologist at BMC.

Catheter ablation is an invasive procedure in which parts of the heart muscle cells are destroyed by heat, freezing, or high-voltage pulses to eliminate sources that cause the heart to beat irregularly. It appeared to be the first-line treatment in patients with symptomatic paroxysmal AF to improve symptoms and slow progression to persistent AF. Catheter ablation was also recommended for patients with AF who have heart failure with reduced ejection fraction (a type of heart failure that occurs when the left ventricle of the heart is too weak to pump enough blood to the body) to improve quality of life. left ventricular systolic function and cardiovascular outcomes, such as mortality rates and hospitalizations for heart failure.

These findings appear in the Journal of the American Medical Association.