What is the role of high-output heart failure in the etiology of dilated cardiomyopathy?

Updated: Nov 28, 2018
  • Author: Vinh Q Nguyen, MD; Chief Editor: Gyanendra K Sharma, MD, FACC, FASE  more...
  • Print
Answer

A high cardiac output is defined as above 8 L/min or a cardiac index beyond 3.9 L/min/m2. The fundamental derangement in high-output heart failure (HOHF) is reduced systemic vascular resistance due to peripheral vasodilation or systemic arteriovenous shunting, with both leading to a decreased mean arterial blood pressure. Consequently, there is a compensatory increase in sympathetic activation, cardiac output, renin-angiotensin-aldosterone system (RAAS), and vasopressin. The result is increased salt/water retention and heart failure. Conditions that cause increased cardiac output include thyrotoxicosis, beriberi, obesity, anemia, Paget disease, AV malformation, AV fistula, and tachycardia syndromes (atrial fibrillation, atrial flutter). Echocardiographic findings of HOHF include compensatory ventricular dilatation and preserved ejection fraction that may deteriorate over time. Mixed venous oxygen saturation is typically over 70%. [26]


Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!