From the Guidelines
LV dysfunction refers to the impaired functioning of the left ventricle of the heart, which is responsible for pumping oxygenated blood to the body, and can be identified in patients presenting with decreased exercise tolerance, fluid retention, or incidentally discovered left ventricular dysfunction. It occurs when the left ventricle cannot contract (systolic dysfunction) or relax (diastolic dysfunction) properly. Common causes include coronary artery disease, heart attacks, high blood pressure, valve disorders, cardiomyopathy, and viral infections. Symptoms may include shortness of breath, fatigue, swelling in the legs, rapid heartbeat, and decreased exercise tolerance.
Diagnosis and Treatment
Diagnosis typically involves echocardiography, which measures the ejection fraction (normally 55-70%), with values below 40% indicating significant dysfunction, as defined by chart documentation of LVEF less than 40% or a narrative description of left ventricular systolic function consistent with moderate or severe systolic dysfunction 1. Treatment depends on severity and may include medications like ACE inhibitors, beta-blockers, diuretics, and aldosterone antagonists.
Lifestyle Modifications and Devices
Lifestyle modifications such as reducing salt intake, regular exercise, smoking cessation, and limiting alcohol are essential. In severe cases, devices like pacemakers, implantable cardioverter-defibrillators, or even heart transplantation may be necessary. Early detection and treatment are crucial as LV dysfunction can progress to heart failure if left untreated, and assessment of left ventricular systolic function is a Class I recommendation in patients with acute myocardial infarction (AMI) 1. Patients with LV systolic dysfunction may be candidates for specific therapies, such as ACE-inhibitor or ARB treatment, and the presence of LV systolic dysfunction may prompt invasive management during ACS hospitalization 1.
From the Research
Definition of LV Dysfunction
LV dysfunction refers to a condition where the left ventricle of the heart does not function properly, leading to inefficient contraction and decreased cardiac output 2. This can be categorized into two types: systolic dysfunction, where the left ventricle is unable to contract effectively, and diastolic dysfunction, where the left ventricle is unable to relax and fill properly 2.
Causes and Pathophysiology
The pathophysiology of LV dysfunction involves the activation of the renin-angiotensin-aldosterone system (RAAS), which leads to vasoconstriction, vascular hypertrophy, and remodeling 3. Angiotensin II plays a critical role in this process, and its inhibition or blockade can help to reduce the progression of heart failure 4, 3.
Diagnosis and Treatment
The diagnosis of LV dysfunction can be made using various imaging techniques, including echocardiography and conductance catheter techniques 5. Treatment options for LV dysfunction include pharmacological therapies such as angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), and aldosterone antagonists 4, 3, 6. Cardiac resynchronization therapy can also be effective in improving clinical symptoms and prognosis in patients with heart failure and LV dyssynchrony 5.
Key Features
Some key features of LV dysfunction include: