Ataxia-telangiectasia

Disease Description (Causes and Symptoms)

• Definition summary: A myocardial disease mainly characterized by dilation of the left ventricle (or both ventricles) and reduced contractile function. It must not be caused by pressure or volume overload due to hypertension, valvular disease, etc., or by obvious coronary artery disease.
• Main causes
  • Genetic causes: Depending on the report, genetic variants are observed in approximately 20–40% of patients, and gene variants may be found in more than 10% of patients even among those without a family history.
  • Acquired causes: Myocarditis caused by viral or other causes, autoimmune diseases, toxicity from alcohol, heavy metals, or medications (e.g., some anticancer drugs), endocrine or metabolic diseases (e.g., diabetes and thyroid disease), and peripartum (postpartum) cardiomyopathy.
• Brief pathophysiology: Myocardial cell damage → ventricular dilation (remodeling) → decreased left ventricular ejection fraction (reduced systolic function) → decreased cardiac output and increased venous pressure → heart failure symptoms and increased risk of arrhythmia and thrombosis.
• Main symptoms
  • Shortness of breath (worsening with activity, orthopnea, trepopnea, and paroxysmal nocturnal dyspnea)
  • General fatigue and exercise intolerance
  • Palpitations (when an arrhythmia is present), fainting, or dizziness
  • Signs of congestion, such as peripheral edema and abdominal distension (ascites)

Treatment Methods

• General principles: Combine medication treatment according to standard heart failure guidelines with treatment of the underlying disease, when possible. The goals are to improve symptoms and prognosis and prevent acute exacerbations.
• Medication treatment (general recommendations)
  • ACE inhibitors, or ARNI (when possible), or ARBs
  • Beta-blockers (heart-rate control and myocardial protection)
  • Mineralocorticoid receptor antagonists (such as spironolactone)
  • SGLT2 inhibitors (beneficial for heart failure indications)
  • Diuretics when necessary (for congestion control)
  • Adjunctive treatments such as iron supplementation (intravenous iron), depending on the case
  • Anticoagulation is indicated in specific situations, such as atrial fibrillation or left ventricular thrombus
• Device and procedural treatments
  • CRT (cardiac resynchronization therapy): When there is ventricular dyssynchrony, such as left bundle branch block, and indications such as EF ≤35%
  • ICD (implantable cardioverter-defibrillator): Selective indications for sudden-death prevention (according to guidelines)
  • Left ventricular assist device (LVAD) and heart transplantation: Considered in end-stage heart failure that cannot be controlled with medication and device treatment
• Treatment of the cause
  • For infectious or autoimmune myocarditis or drug-induced cases, treatment of the cause may be considered (such as antiviral treatment, immunomodulation, or discontinuation of the medication)
  • Discontinuation of causative drugs and alcohol, correction of endocrine diseases, etc.
• Lifestyle management and precautions
  • Limit alcohol and stop smoking; restrict excessive salt intake (as recommended by the doctor); regularly monitor weight and symptoms (shortness of breath and edema)
  • Vaccinations to prevent infections (such as influenza and pneumococcal vaccines) are recommended
  • Caution is needed when taking certain medications (such as cardiotoxic drugs and some antiarrhythmic drugs)
  • Do not stop medications without the specialist’s instructions even if heart failure symptoms improve (the risk of recurrence is high after discontinuation: some sources have reported that remodeling may recur within several months after stopping treatment)

Checklist Before an Outpatient Visit (Including Example Questions)

• Items and information to prepare in advance
  • A list of all medications and supplements currently being taken (including dosage and time of administration)
  • Previous test results (such as echocardiography results, cardiac MRI, and coronary angiography/CT findings) and imaging images, if possible
  • A record of recent symptom changes (worsening shortness of breath, weight changes, chest pain, fainting, etc.) and when they began
  • Weight, blood pressure, and heart rate measurements, if possible, recorded over several days
  • Family history (heart failure, cardiomyopathy, sudden death, etc.), alcohol consumption history, and occupational exposure history (toxic substances)
  • Whether there are plans for pregnancy (for women)
• Items to check during the outpatient visit (key information to present to the doctor)
  • Recent hospitalization history and details of emergency treatment
  • Whether a transplant or device (pacemaker/ICD/LVAD) has been implanted
• Example questions (questions for patients to check for themselves before the visit)
  • When did the symptoms begin, and what were they? What factors worsen them (exercise, meals, medication changes, etc.)?
  • Has your weight increased rapidly recently (by 1–2 kg or more per day), or have you developed edema?

Examples of General Questions to Ask the Doctor

• "What are the main side effects and precautions for this medication I am taking?"
• "What is my ventricular systolic function (ejection fraction), and what is my expected prognosis?"
• "To what extent are exercise (aerobic and strength training) or work activities safe for me?"
• "What symptoms should prompt me to visit the emergency room immediately?"

Examples of Disease-Specific Questions

• "Since there may be a hereditary cause, do you recommend genetic testing? Do my family members need screening tests?"
• "Given my condition, what are the specific criteria for considering implantation of an ICD (defibrillator) or CRT (resynchronization therapy)?"