Withdrawal of Heart Failure Treatment Patients With Non-ischemic Cardiomyopathy Who Have Been Super-responders to Cardiac Resynchronization Therapy.

Prior treatment

• CRT devices implanted as an upgrade from prior pacemaker or ICD, where prior pacing percentage was \>20%

Other illness

• Severe valvular heart disease
• History of sustained ventricular arrhythmia or treated by ICD
• Need to maintain beta-blocker therapy for other arrhythmias
• Hypertension not controlled with other medications
• Clinical indication other than heart failure to maintain any of the neurohormonal treatment drugs (class I recommendation in ESC or ACC/AHA guidelines)

Lab values

• Family history of non-ischemic cardiomyopathy with LVEF \<50% in at least one first-degree relative

• Diagnosis of non-ischemic cardiomyopathy
• LBBB already present at the time of first diagnosis of LV dysfunction
• Negative genetic test
• Cardiac MRI with no evidence of late gadolinium enhancement (LGE at RV insertion points is acceptable)
• Carrier of a resynchronization device (ICD or pacemaker, with LV epicardial pacing form a cardiac vein or left bundle area pacing), pacing percentage \>95% and paced QRS \<140 ms
• Device indication: LVEF ≤35% and LBBB with QRS \>150 ms
• LVEF ≥50% and normal indexed LV volumes on echocardiogram performed at least 6 months after CRT implantation
• No heart failure decompensations (no hospitalizations or urgent/day hospital visits) since CRT implantation
• No need for loop diuretic treatment
• NYHA class I or II
• NT-proBNP \<450 ng/L (or \<1000 ng/L in atrial fibrillation/flutter)
• On neurohormonal therapy with at least two drugs