Table 4. Clinical cases for referral of patients with HF to a HF cardiologist.

Clinical scenario	When/why
1. New-onset (de novo) HF	For evaluation of etiology, guideline-directed evaluation, and management of recommended therapies
2. Chronic HF with high-risk features	i) Need for intravenous inotropic therapy due to sustained NYHA functional class III-IV symptoms of congestion or profound fatigue or systolic blood pressure less than 90 mmHg and/or symptomatic hypotension
	ii) New onset of atrial fibrillation, ventricular arrhythmias, or repetitive ICD shocks
	iii) Two or more emergency department visits or hospitalizations for worsening HF in the prior 12 months
	iv) Inability to tolerate optimally dosed beta-blockers and/or ACEI/ARB/ARNI and/or aldosterone antagonists
	v) Clinical deterioration, as indicated by worsening edema, rising biomarkers (BNP, NT-proBNP, others), worsened exercise testing, decompensated hemodynamics, or evidence of progressive remodeling on imaging
3. Persistently reduced LVEF ≤35% despite guideline-directed medical therapy for 3 months	For consideration of device therapy in patients without prior placement of ICD or CRT
4. Second opinion is needed regarding the etiology of HF	i) Coronary ischemia and the possible value of revascularization
	ii) Valvular heart disease and the possible value of valve repair
	iii) Suspected myocarditis
	iv) Established or suspected specific cardiomyopathies (for example, hypertrophic cardiomyopathy, arrhythmogenic right ventricular dysplasia, restrictive cardiomyopathy, cardiac sarcoidosis, and amyloidosis)

HF = heart failure; NYHA = New York Heart Association; ICD = implantable cardioverter-defibrillator; ACEI = angiotensin-converting enzyme inhibitor; ARB = angiotensin receptor blocker; ARNI = angiotensin receptor neprilysin inhibitor; BNP = B-type natriuretic peptide; NT-proBNP = N-terminal pro B-type natriuretic peptide; CRT = cardiac resynchronization therapy.