From the Guidelines
For patients with left ventricular noncompaction (LVNC) and a history of syncope, guideline-directed medical therapy (GDMT) should generally be initiated first, with concurrent evaluation for ICD placement. Start with standard heart failure medications including beta-blockers (such as metoprolol 25-200 mg daily or carvedilol 3.125-25 mg twice daily), ACE inhibitors or ARBs (such as lisinopril 5-40 mg daily or valsartan 40-320 mg daily), and mineralocorticoid receptor antagonists (spironolactone 25-50 mg daily) if ejection fraction is reduced. However, if the syncope is determined to be arrhythmic in nature or if the patient has severe LV dysfunction with an ejection fraction ≤35% despite optimal medical therapy, ICD implantation should be prioritized, as recommended by the 2014 HRS/ACC/AHA expert consensus statement 1. The decision requires comprehensive evaluation including cardiac MRI to assess the extent of noncompaction, Holter monitoring to detect arrhythmias, and electrophysiology studies if needed. LVNC predisposes patients to ventricular arrhythmias and sudden cardiac death, particularly when associated with syncope, which is why risk stratification is crucial. While GDMT helps improve cardiac function and may reduce arrhythmic risk, it cannot provide the immediate protection against life-threatening arrhythmias that an ICD offers for high-risk patients.
Some key points to consider in the management of these patients include:
- The importance of initiating GDMT as the first line of treatment
- The need for concurrent evaluation for ICD placement, especially in patients with severe LV dysfunction or arrhythmic syncope
- The role of comprehensive evaluation, including cardiac MRI, Holter monitoring, and electrophysiology studies, in guiding the decision for ICD implantation
- The recommendation for ICD implantation in patients with syncope thought to be due to a ventricular tachyarrhythmia, as stated in the 2014 HRS/ACC/AHA expert consensus statement 1.
It is also important to note that the 2013 ACCF/AHA guideline for the management of heart failure recommends ICD therapy for primary prevention of SCD in selected patients with HFrEF, including those with LVEF ≤35% and NYHA class II or III symptoms on chronic GDMT 1. However, the specific recommendation for patients with LVNC and syncope is not explicitly stated in this guideline, highlighting the need for individualized decision-making and consideration of the latest expert consensus statements, such as the 2014 HRS/ACC/AHA statement 1.
From the Research
GDMT or ICD First in Patients with LV Noncompaction and History of Syncope
- The decision to prioritize Guideline-Directed Medical Therapy (GDMT) or an Implantable Cardioverter-Defibrillator (ICD) in patients with Left Ventricular Noncompaction (LVNC) and a history of syncope should be based on individual risk assessment and clinical judgment.
- According to the study by 2, Left Ventricular Ejection Fraction (LVEF) is a significant predictor of major adverse cardiovascular events (MACE) in patients with LVNC.
- Patients with LVNC and reduced LVEF (<50%) are at higher risk of adverse outcomes, including heart failure, ventricular arrhythmias, and sudden cardiac death, as reported by 3 and 4.
- The presence of syncope in patients with LVNC may indicate an increased risk of ventricular arrhythmias and sudden cardiac death, suggesting the potential benefit of ICD therapy, as discussed by 5.
- However, the study by 6 highlights the importance of considering baseline Left Ventricular Dilation and Dysfunction in assessing the risk of death or heart transplantation in patients with LVNC.
- A comprehensive risk assessment, including evaluation of LVEF, presence of late gadolinium enhancement, and family history of sudden cardiac death, can help guide the decision to prioritize GDMT or ICD therapy in patients with LVNC and a history of syncope, as proposed by 2.