🫀 Aortic Valve Degeneration in Horses 🫀 Aortic valve degeneration is a progressive condition in horses characterized by thickening, fibrosis, and dysfunction of the aortic valve leaflets, often leading to aortic regurgitation. This valvular insufficiency results in chronic volume overload of the left ventricle, eccentric hypertrophy, reduced cardiac output, and eventual heart failure. Horses may initially present with exercise intolerance and a diastolic murmur, progressing to arrhythmias and clinical signs of left-sided heart failure. Early diagnosis and appropriate management are essential to slow disease progression and mitigate complications such as atrial fibrillation or sudden death.

🧬 Comprehensive Information on Equine Congenital Heart Disease (CHD) for NAVLE Preparation 🐴 Congenital heart disease (CHD) in horses encompasses a group of structural cardiac defects present at birth, resulting from abnormal embryologic development of the heart and great vessels. While some defects remain clinically silent, others can lead to significant hemodynamic compromise, exercise intolerance, failure to thrive, or sudden death in foals and young horses. Common congenital anomalies include ventricular septal defects (VSD), patent ductus arteriosus (PDA), atrial septal defects (ASD), and complex malformations like tetralogy of Fallot. This note provides in-depth knowledge of the embryology, pathophysiology, clinical signs, diagnostic imaging, and management options for equine CHD, tailored to support veterinary professionals preparing for the NAVLE.

🫀 Detailed Information on Atrial Foramen Ovale Defect in Foals for NAVLE Preparation 🐎 Patent foramen ovale (PFO) is a congenital cardiac anomaly in foals resulting from the failure of the foramen ovale to close after birth. Normally, this fetal structure allows right-to-left atrial shunting to bypass the nonfunctional lungs in utero, but postnatally, increased left atrial pressure should cause functional closure. Persistence of this opening leads to abnormal interatrial blood flow, which may be asymptomatic or contribute to exercise intolerance, right-sided volume overload, and heart failure if significant. This note outlines the embryology, pathophysiology, clinical signs, diagnostic approach (especially echocardiography), and management of PFO, helping veterinary professionals master this topic for NAVLE preparation.

🔎 Detailed Information on Cardiac Arrhythmias in Horses for NAVLE Preparation 🐎 Cardiac arrhythmias are a common and clinically significant finding in horses, ranging from benign physiologic variants to life-threatening rhythm disturbances. Understanding the classification, causes, and clinical impact of arrhythmias—such as atrial fibrillation, ventricular premature depolarizations, and atrioventricular blocks—is essential for accurate diagnosis and management. This section provides an in-depth review of equine arrhythmias, including detailed pathophysiology, ECG interpretation, diagnostic approaches, and treatment options, to equip veterinary professionals with the critical knowledge needed for NAVLE success.

Rhodococcus equi pneumonia is a serious and often fatal disease in foals, typically affecting those between 1 to 6 months of age. This gram-positive facultative intracellular bacterium causes chronic suppurative bronchopneumonia and pulmonary abscessation, often accompanied by extrapulmonary disorders such as diarrhea, uveitis, or septic arthritis.