How should I manage a 54-year-old man with known hypertrophic cardiomyopathy who is asymptomatic and whose echocardiogram shows mild‑to‑moderate concentric left‑ventricular hypertrophy, preserved ejection fraction of 65 %, mild bi‑atrial enlargement, normal right‑ventricular size and function, grade 1 diastolic dysfunction, and mild tricuspid regurgitation?

Management of Asymptomatic HCM with Mild-to-Moderate LVH

This asymptomatic 54-year-old man with mild-to-moderate HCM requires annual clinical surveillance, repeat echocardiography every 1–2 years, and 24-hour Holter monitoring every 1–2 years to screen for sudden cardiac death risk factors and disease progression. 1, 2

Immediate Assessment for Left Ventricular Outflow Tract Obstruction

• Perform provocative maneuvers during the next echocardiogram (Valsalva, squat-to-stand, or standing) because resting gradients miss dynamic LVOTO in approximately 50% of cases. 1, 2, 3
• If bedside maneuvers fail to provoke a gradient ≥50 mm Hg and the patient remains asymptomatic, exercise stress echocardiography may be considered when the presence of LVOTO is relevant to lifestyle advice. 1
• The current echo shows no mention of LVOT gradient measurement at rest or with provocation—this must be documented to guide management. 1, 3

Sudden Cardiac Death Risk Stratification

• Order 24-hour Holter monitoring immediately if not already done, as detection of non-sustained ventricular tachycardia (≥3 beats at ≥120 bpm) is a major risk factor for sudden cardiac death. 1, 2, 3
• Document maximal wall thickness precisely; the current report states "mild to moderate concentric LVH" but does not provide millimeter measurements—wall thickness ≥30 mm confers high SCD risk. 2
• Obtain a detailed three-generation family history focusing on premature sudden cardiac death (<50 years) from HCM, which is a major risk factor. 1, 2
• Ask specifically about any history of unexplained syncope, as this is a high-risk feature for sudden cardiac death. 2
• Consider cardiac MRI to detect apical aneurysm (a high-risk feature often missed on standard echo) and to quantify late gadolinium enhancement, as LGE ≥15% of LV mass indicates 2-fold increased SCD risk. 2, 4

Evaluation of Diastolic Dysfunction and Atrial Enlargement

• The grade 1 diastolic dysfunction and mild biatrial enlargement reflect elevated LV filling pressures and impaired relaxation, which are common in HCM even when asymptomatic. 1
• Comprehensive diastolic assessment should include E/A ratio, E/e' ratio, pulmonary vein flow velocities, and pulmonary artery systolic pressure to stage disease severity. 1
• A restrictive filling pattern (E/A ≥2, E-wave deceleration time ≤150 ms) indicates higher risk for adverse outcomes even with preserved ejection fraction—this should be documented. 1
• Biatrial enlargement is multifactorial but commonly results from elevated LV filling pressures and potential mitral regurgitation from systolic anterior motion. 1

Assessment of Mitral Regurgitation

• The current echo does not mention mitral regurgitation severity or mechanism—this must be evaluated at rest and with provocation. 1, 3
• Look for systolic anterior motion of the mitral valve, which causes secondary MR that is typically mid-to-late systolic and posteriorly directed. 1
• Assess for primary mitral valve abnormalities (excessive leaflet length, anomalous papillary muscle insertion, anteriorly displaced papillary muscles) that may contribute to MR independent of LVOTO. 1

Right Ventricular and Tricuspid Valve Assessment

• The mild tricuspid regurgitation and normal RV size/function are reassuring, as significant RV involvement in HCM can cause severe dyspnea, supraventricular arrhythmias, and pulmonary thromboembolism. 5
• Increased RV free wall thickness would suggest infiltrative disease (amyloidosis, Fabry disease) or Noonan syndrome rather than typical HCM. 1, 4

Ongoing Surveillance Schedule

• Repeat transthoracic echocardiography every 1–2 years to monitor for progression of hypertrophy, development of LVOTO, worsening diastolic dysfunction, or decline in systolic function. 1, 2, 3
• Repeat 24-hour Holter monitoring every 1–2 years to screen for new non-sustained ventricular tachycardia. 1, 2, 3
• Obtain annual 12-lead ECGs to assess for rhythm changes, conduction abnormalities, or emergence of atrial fibrillation. 2
• Clinical follow-up visits should occur annually to reassess symptoms, functional capacity, and any new family history of sudden cardiac death. 1

Lifestyle and Activity Counseling

• Advise against competitive sports and high-intensity isometric exercise until complete risk stratification is finished. 2
• Recreational activities should be tailored to symptoms and SCD risk profile once fully assessed. 1
• Counsel on avoiding dehydration and excess alcohol, particularly if LVOTO is present, as these worsen obstruction. 1
• Large meals can precipitate chest pain in patients with LVOTO; recommend smaller, more frequent meals if obstruction is documented. 1

Medications to Avoid

• Do not prescribe vasodilators (ACE inhibitors, ARBs, nitrates), high-dose diuretics, or digoxin, as these can worsen LVOTO if present. 2
• Avoid phosphodiesterase-5 inhibitors (sildenafil, tadalafil), particularly if LVOTO is documented. 1
• Peripheral vasodilators should be avoided in general. 1

Family Screening Protocol

• All first-degree relatives require ECG and echocardiographic screening. 2, 3
• Relatives aged 12–21 years should be screened every 12–18 months. 2
• Adult relatives (>21 years) should be screened every 5 years or sooner if symptoms develop. 2
• Consider genetic testing; mutation-negative relatives may discontinue ongoing cardiac screening. 2

When to Consider Advanced Imaging

• Order cardiac MRI if apical hypertrophy or apical aneurysm is suspected, as these are poorly visualized on standard echo. 2, 3
• CMR is indicated if echocardiographic windows are suboptimal or if infiltrative disease (amyloidosis, Fabry disease) is suspected based on clinical features. 2, 4
• CMR with late gadolinium enhancement helps quantify myocardial fibrosis, which predicts progression to advanced heart failure and guides ICD decision-making. 2, 4, 6

Critical Pitfalls to Avoid

• Do not assume the patient is low-risk simply because he is asymptomatic—sudden cardiac death can be the first manifestation of HCM, particularly in young patients. 1, 2
• Do not perform echocardiography without provocative maneuvers, as this misses dynamic LVOTO in half of cases. 1, 2, 3
• Do not overlook apical HCM, which may be invisible on standard echo and requires contrast echo or CMR. 2, 3
• Do not miss family screening—HCM follows autosomal-dominant inheritance, giving first-degree relatives a 50% chance of carrying the mutation. 2
• Do not attribute all concentric LVH to hypertension without excluding HCM, as HCM prevalence is approximately 1:500. 2

Consideration of Emerging Therapies

• Mavacamten, a cardiac myosin inhibitor, is FDA-approved for obstructive HCM but is not indicated in asymptomatic patients without LVOTO. 7
• This patient would not be a candidate for mavacamten unless symptomatic LVOTO ≥50 mm Hg is documented and symptoms are refractory to beta-blockers or calcium channel blockers. 1, 7

Prognosis and Counseling

• With contemporary management including appropriate risk stratification, ICD placement when indicated, and effective anticoagulation for atrial fibrillation, near-normal life expectancy and highly satisfactory quality of life are realistic goals. 8, 6
• Approximately 5% of HCM patients progress to "end-stage" HCM with reduced ejection fraction <50%, while others develop advanced diastolic dysfunction with restrictive physiology—both pathways carry increased mortality risk. 9
• The presence of grade 1 diastolic dysfunction and biatrial enlargement in this patient suggests early disease progression that warrants close surveillance. 1, 9