List causes for ADHF.
Uncontrolled and/or refractory hypertension (see “Hypertensive emergencies”)
New/worsening cardiac ischemia
Arrhythmias (e.g., atrial fibrillation with RVR, complete heart block)
Serious infection/sepsis (e.g., pneumonia)
Nonadherence to heart failure medication
Drugs with negative inotropic properties (e.g., nondihydropyridine CCBs) 
Starting or uptitrating beta blockers 
Recreational substance use, e.g., cocaine, alcohol, methamphetamines
Volume overload, e.g., due to inappropriate fluid/salt intake or IV fluid therapy
In 40–50% of cases, no trigger is found.
List causes for de novo heart failure.
Acute myocardial dysfunction
Cardiac ischemia due to acute coronary syndrome (ACS)
Drug-induced cardiomyopathy 
Acquired valvular pathology
Acute mitral regurgitation after ACS
Nonbacterial thrombotic endocarditis
Extracardiac pathologies that affect left ventricular output
Pericardial effusion causing tamponade