Valvular heart disease

1. Disease Description (Causes and Symptoms)

• Disease name confirmation: Dilated cardiomyopathy (영lish: Dilated cardiomyopathy, DCM) is a medically accepted term.
• Definition·pathophysiology: It is characterized by dilation of the left ventricle or both ventricles and reduced contractile function (decreased LVEF), in the absence of clear causes of pressure/volume overload such as hypertension, valvular disease, or severe coronary artery disease. Cardiac muscle remodeling, myocardial fibrosis, intracardiac thrombus formation, and an increased risk of ventricular and atrioventricular arrhythmias may also occur.
• Main causes:
  • Genetic causes: Depending on the report, gene mutations are observed in 20–40% of familial patients and genetic abnormalities in ≥10% of nonfamilial patients. Consider family history and genetic testing.
  • Acquired causes: Viral or other infectious myocarditis, autoimmune myocardial injury, excessive alcohol consumption·heavy metal toxicity, drug toxicity such as anticancer drugs (e.g., anthracyclines), endocrine·metabolic diseases (thyroid disease, diabetes, etc.), and peripartum (postpartum) cardiomyopathy.
• Main symptoms:
  • Shortness of breath (worsening with activity), orthopnea (worsening when lying down), paroxysmal nocturnal dyspnea
  • Fatigue, reduced exercise capacity
  • Palpitations (arrhythmia), syncope or dizziness (in cases of severe arrhythmia)
  • Risk of embolism due to left ventricular thrombus (including stroke)
• Key diagnostic tests (summary): Chest X-ray (cardiomegaly/pulmonary congestion), echocardiography (evaluation of ventricular dilation·reduced contraction·intracardiac thrombus·valvular regurgitation), cardiac MRI (evaluation of myocardial inflammation·fibrosis·infiltration), coronary CT/angiography (exclusion of coronary artery disease), and, if necessary, myocardial biopsy (when autoimmune·infiltrative disease is suspected).

2. Treatment Methods

• Treatment goals: Relieve symptoms, preserve/restore cardiac function (induce reverse remodeling), prevent complications (worsening heart failure·arrhythmia·embolism), and improve survival.
• Drug treatment (based on heart failure guidelines, standard therapy):
  • ACE inhibitors or ARBs; recently, use of ARNI (sacubitril/valsartan) is recommended (depending on the indication)
  • Beta-blockers (cardiac protection·induction of reverse remodeling)
  • Mineralocorticoid receptor antagonists (such as spironolactone)
  • SGLT2 inhibitors (when indicated for heart failure)
  • Diuretics (symptom control: pulmonary congestion·edema)
  • Anticoagulation: Anticoagulants are used according to the indication in patients with left ventricular thrombus or atrial fibrillation·a high risk of embolism
• Device treatment and procedures·surgery:
  • Implantable cardioverter-defibrillator (ICD): Prevention of life-threatening arrhythmias (according to primary·secondary prevention criteria)
  • Cardiac resynchronization therapy (CRT): Improvement of symptoms·survival in patients with significant left ventricular contraction dyssynchrony (e.g., LBBB, widened QRS) and low EF
  • Left ventricular assist device (LVAD) and heart transplantation: Considered for patients with end-stage heart failure that cannot be controlled with drug·device treatment
• Treatment of the cause: Concurrent treatment of the underlying disease (myocarditis, thyroid·metabolic disease, discontinuation of causative drugs, etc.)
• Lifestyle management and prevention: Low-salt diet·weight management·regular weight and symptom (shortness of breath, edema) monitoring, avoidance of alcohol·harmful drugs, influenza·pneumococcal vaccination is recommended, and severe strenuous exercise should follow symptoms·the doctor's recommendations
• Precautions:
  • Even if symptoms improve and LVEF gets better, discontinuing medication may lead to reduced contractile function and recurrence of remodeling in approximately 44% of patients within a short period (within 6 months), according to the data; the need to continue medication should therefore be considered.
  • Patients planning pregnancy or with a history of peripartum cardiomyopathy require specialized counseling.
• Complications: Worsening heart failure, syncope·sudden death due to ventricular arrhythmias, left ventricular thrombus and embolism, anemia·liver and kidney function problems (complications of heart failure), etc.

3. Outpatient Visit Checkpoints (Including Example Questions)

• Items to prepare (recommended to bring): A list of all medications currently being taken (including prescriptions·over-the-counter medicines·supplements), copies of previous test results (echocardiography·electrocardiography·cardiac CT/MRI·blood tests), a record of symptom changes (when they began and under what circumstances they worsen), recent weight changes and blood pressure·heart rate records, family history (heart failure·sudden cardiac death·genetic diseases), and pregnancy status (women of childbearing age)
• Items helpful to record for the medical visit: Pattern of worsening shortness of breath (relationship to activity level), symptoms when sitting vs. lying down, nighttime shortness of breath, syncope or presyncope, presence of chest pain, and history of alcohol·drug use
• Tests·symptoms to show the doctor directly at the outpatient visit: Recent echocardiography results (if possible, the image files·report), electrocardiogram (ECG), and BNP/NT‑proBNP test results (if available)
• Example questions (questions the patient can ask the doctor directly in the consultation room):
  • "What is my current LVEF (left ventricular ejection fraction)?"
  • "How long do I need to take the medication?"
  • "Are there any precautions I should take during exercise or daily activities?"

4. Examples of General Questions to Ask the Doctor

• What are the expected benefits and possible side effects of this medication?
• With my current cardiac function (e.g., LVEF), do I need an ICD or CRT?
• How likely is it that my myocardial function will improve (possibility of reverse remodeling)?
• What risks are associated with stopping the medication on my own?
• Is pregnancy (or planning a pregnancy in the future) possible? What preparation and management are needed?

5. Examples of Disease-Specific Questions

• Regarding the possibility of a genetic cause: "Depending on my family history or genetic test results, do you recommend genetic testing or cardiac screening for my family members (such as children)?"
• Regarding recurrence·discontinuation of medication: "If my LVEF improves, can I reduce or stop the medication, and how should the risk of recurrence be managed if I stop it?"

Reference (summary): Dilated cardiomyopathy occurs due to various genetic·acquired causes and mainly presents with shortness of breath·fatigue·arrhythmia. Diagnosis is made through echocardiography·cardiac MRI·coronary artery testing, and treatment consists of guideline-based drug therapy for heart failure and, when necessary, an ICD/CRT·heart transplantation, etc. Some patients may improve through reverse ventricular remodeling, but there is a risk of recurrence when medication is discontinued, so long-term management is necessary.