Introduction
Heart failure is one of the most widespread and most rapidly growing cardiovascular diseases in the United States, affecting 1 in 100 adults above 65 years of age. Regardless of advances in treatment, the rate of heart failure continues to rise. Recent developments in managing heart failure have included the development of mechanical device-based therapies to target anomalies that cannot be targeted with current medical treatments.
These device-based mechanical therapies are referred to as "interventional" therapies. Interventional heart failure therapies are further categorized into 10 subgroups as follows:
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Interventional medical therapy.
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Electrical therapy.
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Treatment of coronary disease
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Treatment of valvular disease.
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Fluid removal.
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Mechanical circulatory assist devices.
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Ventricular support and restoration.
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Tissue transplant.
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Palliative care.
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Self-care.
Although the latter two subgroups are not mechanical device-based therapies, they are considered interventional heart failure therapy because they are important for the management of heart failure. This article briefly explains the interventional therapies that are used in heart failure management.
What Interventional Therapies Are Used in the Management of Heart Failure?
1. Interventional Medical Therapy
Inotropes such as dopamine, dobutamine, and milrinone are drugs that are used in treating acute heart failure. Their short-term use of these drugs has proven to be beneficial. The long-term use of inotropes in patients with end-stage heart failure has remained controversial as it increases the risk of ventricular arrhythmias, sudden death, and increased mortality.
However, the use of ICD (implantable cardiac defibrillator) in patients with long-term use of inotropes decreases the risk of sudden death in these patients.
2. Electrical Therapy.
Heart failure increases the risk of developing arrhythmias (abnormal heartbeat) and sudden death because of changes in heart structure, unregulated neurohormonal activation, and scarred muscle of the heart that may act as a trigger for malignant ventricular arrhythmias. Various electrical therapies are used to treat heart failure, which include:
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Implantable Cardiac Defibrillator (ICD): An implantable cardiac defibrillator (ICD) is a device attached to the myocardium (muscle of the heart). It has been proven to reduce the mortality of patients with heart failure. The device monitors the activity of the heart, and when malignant ventricular arrhythmias are detected, it sends an electrical shock to the myocardium to restore normal heart rhythm.
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Cardiac Resynchronization Therapy: Patients with heart failure may result in abnormal contractions of the lower heart chamber - dyssynchronous ventricular contraction. Cardiac resynchronization therapy is a type of electrical therapy that has been designed to restore ventricular synchrony; this is achieved with the use of a biventricular pacemaker attached to the right and left ventricles through separate leads, which improves coordination and makes the heart work better.
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Cardiac Contractility Modulation: Cardiac contractility modulation (CCM) is a new therapy that is currently in clinical trials. In current research, CCM shows promise in the treatment of patients with end-stage heart failure. It uses a pulse generator to deliver electrical impulses to the myocardium to improve the heart contractions.
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Vagal Nerve Stimulation: In heart failure, there is an increase in sympathetic tone, which leads to ventricular dilation and worsening heart failure. Drugs like B-blockers reverse this process and improve survival in heart failure; however, these drugs show some side effects, such as hypotension and bradycardia. A recent advance in electrical therapy called vagal nerve stimulation has been introduced that also acts by counteracting sympathetic tone. In vagal nerve stimulation, a pacemaker-like device is implanted subcutaneously and is attached to the vagus nerve. The electrical signal from this device can be adjusted to optimize vagal tone until the desired heart rate of the patient is achieved. Vagal nerve stimulation is still under investigation, and more research is needed to confirm its effectiveness.
3. Treatment of Coronary Artery Disease:
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Risk Factor Reduction: The current treatment of coronary artery disease involves risk factor reduction, which can be achieved through a combination of lifestyle modification and drug therapy. This improves the survival rate of heart failure patients and improves their quality of life.
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Coronary Artery Bypass Graft (CABG) Surgery: It is considered to be a standard of care for select patients with blocked coronary arteries as it has long-term survival benefits.
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Percutaneous Coronary Intervention (PCI): Even though CABG is generally accepted, many people have begun to use percutaneous coronary intervention as it is less invasive, allows faster recovery in patients, and reduces the length of hospitalization.
4. Treatment of Valvular Disease:
Heart failure is often associated with secondary or functional mitral valve regurgitation, where the mitral valve does not close properly, sometimes causing blood to leak back into the heart. The treatment of mitral valve regurgitation is usually not required. However, surgical correction of functional mitral regurgitation is sometimes performed in some patients; minimally invasive approaches for the treatment of mitral regurgitation have also been developed and, in the future, may provide additional treatment options for these patients.
5. Fluid Removal:
In severe heart failure, the body retains water and salt, worsening symptoms like swelling and shortness of breath. The use of traditional drugs such as diuretics removes fluids, but these drugs can have side effects like low blood pressure and electrolyte imbalances. The new technique includes:
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Interventional Vasodilatation: This technique involves delivering the drugs directly to the kidneys through catheters to improve blood flow and water removal. This is achieved through an approach called targeted renal therapy (TRT). It is a specific type of vasodilatation using a device to deliver drugs to the renal arteries.
6. Mechanical Circulatory Support Devices:
Mechanical circulatory support devices such as intra-aortic balloon pumps, continuous aortic flow augmentation, catheter-based pumps, ventricular assist devices, and total artificial hearts are used in interventional heart failure therapy to stabilize patients with severe heart failure and improve outcomes.
7. Ventricular Support and Restoration: Ventricular support and restoration are surgical interventions that aim at altering the shape, size, or contractions of the left ventricle. Ventricular support involves wrapping the heart with materials that support its structural strength; ventricular restoration involves surgically reshaping the left ventricle to its natural size and shape. The techniques include cardiomyoplasty, passive ventricular restraint, and surgical ventricular restoration (SVR).
8. Tissue Transplant:
Tissue transplantation uses living cells or tissue to restore cardiac pump function; it includes cellular therapy, stem cell therapy, and heart transplant.
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Cellular and Stem Cell Therapy: One potential treatment for ischemic heart disease is cellular and stem cell therapy. In this therapy, the living cells are injected into heart tissue, improving the pump function of the heart. However, further research is needed to address safety concerns.
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Heart Transplant: Heart transplantation provides a life-saving option for patients with end-stage heart failure who have failed other available treatment options.
9. Palliative Care: Identifying and treating patients' physical (fatigue, shortness of breath) and psychological (anxiety, depression) symptoms with evidence-based interventions is a key component of palliative care. Patients and their families should also be kept fully informed about the natural course of heart failure, expected symptoms, risk of sudden cardiac death, and impact on longevity.
10. Self-Care: It involves adopting lifestyle changes such as taking prescribed drugs, following a low-sodium diet, consuming fewer fluids, exercising, and identifying the warning signs and symptoms of increasing heart failure when they appear.
Conclusion
Interventional therapies are rays of hope in the battle against heart failure by improving survival, enhancing quality of life, and maintaining heart health for patients worldwide. As research continues to advance, the field of interventional heart failure therapies will continue to expand, offering new treatment options for patients living with this challenging condition.
