Heart Failure
Heart failure is a complex clinical syndrome that is characterized by impaired myocardial performance. There is progressive maladaptive neurohormonal activation of the cardiovascular and renal systems that leads to circulatory insufficiency and congestion. Acute heart failure syndromes (AHFS) are more common in older patients. Systolic heart failure is due to the contractility of the left ventricle. Congestive heart failure is overused and applied to the states of hypervolemia unrelated to cardiac dysfunction.
Pathogenesis of Heart Failure
The heart failure is a progressive disorder caused due to myocardial injury. The injury may include acute disruptions in myocardial function. There is a chronic derangement including familial and metabolic cardiomyopathies or chronic volume and pressure related to valulopathies, intracardiac shunts, or systemic hypertension. Neurohormonal activation includes activation of RAS and sympathetic nervous system. It also includes other neural derangements.
Classification of Heart Failure
- Stage A- At this stage, patients are at high risk of developing heart failure without any symptomatic heart failure or structural heart disease.
- Stage B- At this stage, patients have structural heart disease but may not develop any symptoms of heart failure.
- Stage C- The patients have structural heart disease with prior or current symptoms of heart failure.
- Stage D- At this stage, patients have refractory end-stage heart failure that requires specialized advanced treatment.
Causes of Heart Failure
What are the common causes of Heart Failure?
- Ischemic cardiomyopathy
- Dilated cardiomyopathy
- Familial dilated cardiomyopathy
- Hypertensive and diabetic cardiomyopathy
- Cardiotoxic agents- It includes chemotherapeutic agents, alcohol, stimulant drugs, and toxin exposures.
- Inflammatory cardiomyopathy
- Tachyarrhythmia-induced cardiomyopathy
- Peripartum cardiomyopathy
- Valvular disorders
- Miscellaneous disorders- It includes thyroid disorders (Hypothyroidism, Hyperthyroidism), thiamine deficiency (beriberi), other nutritional deficiencies, high-output heart failure from anemia
- Hemochromatosis
- Inherited myopathies
- Cardiac sarcoidosis
- Chagas disease- It is caused by flagellate protozoan Trypanosoma cruzi.
Signs and Symptoms of Heart Failure
What are the common symptoms of Heart failure?
- Dyspnea typically with exertion.
- Orthopnea (most sensitive and specific sign)
- Paroxysmal nocturnal dyspnea
- Cheyne-Stokes respiratory patterns
- Fatigue
- Exercise intolerance
- Nocturnal cough
- Insomnia
- Depressed mood
- Palpitations
- Syncope
- Anorexia
- Abdominal pain
- Volume overload is the hallmark of congestive heart failure.
- Weight gain
- Acute cardiogenic pulmonary edema
- Jugular venous distension/ elevated jugular venous pressure
- Pedal edema
- Ascites and hepatomegaly
- A third heart sound that is S3 gallop
- Tachycardia and narrow pulse pressure
- Lethargy
- Pallor
- Mottled skin and cool extremities
- Poor capillary refill
- Hypotension (Blood pressure <90 mm of Hg) is a strong indicator of morbidity and mortility.
How to diagnose Heart Failure?
- Comprehensive metabolic panel- It should be assessed on initial evaluation and the based on clinical judgement. Hypokalemia is coomon in ongoing diuretic therapy. Hyperkalemia can be seen by over aggressive potassium repletion. Transaminities and in some cases of cholestatic pattern of liver functioning test abnormalities can be seen while considering right heart failure.
- Anemia- It is present in about 40 % of heart failure patients. It is associated with increased mortality and functional impairments. While considering anemia, a diagnostic evaluation should be performed.
- Natriuretic peptides- These include B-type natriuretic peptide (BNP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP). They are released to increase ventricular dilation or wall stress.
- Other biomarkers- These biomarkers assess systemic inflammation, oxidative stress, extracellular matrix remodeling or myocyte injury is commercially available.
- Thyroid functioninf tests- These tests are important for diagnosing all the patients with heart failure.
- The electrocardiogram (ECG)- It is a recommended component in diagnosing the heart failure. It provides information about the cause and management of heart failure.
- Chest radiograph- It is important for the assessment of heart size and the condition of pulmonary parenchyma.
- Ecocardiography- It provides information about cause and prognosis of heart failure. It is important in the diagnostic evaluation of congestive heart failure.
Treatment of Heart Failure
How to treat Heart Failure?
- Invasive hemodynamic monitoring should be performed by using pulmonary artery catheter and arterial catheter.
- By maximizing oxygenation
- Use of vasodilators for the management of cardiogenic pulmonary edema. The commonly used vasodilators are nitroglycerin (reduces LV filling pressures), sodium nitroprusside, nesiritide (an intravenous vasodilator that has use in the absence of invasive hemodynamic monitoring).
- Use of diuretics
- Inotropic therapy
- Ultrafiltration
- Vasopression antagonists
- Patient education and disease management programs should be introduced.
