Concerning the adaptation to cardiac valvular dysfunction, the following is/are true:

a. Severe heart failure is more likely from acute than chronic valvular dysfunction

b. Valvular dysfunction produces both volume and pressure afterload stress on the heart

Valvular dysfunction produces both volume and pressure overload representing afterload stress on the heart. Although cardiac reserves allow for gradual adaptation to chronic valvular dysfunction, acute dysfunction is less well tolerated and more likely to result in severe heart failure. The increase in diastolic filling which initially dilates the heart, shifts the Frank-Starling curve to improve ejection and cardiac output. The LaPlace law predicts that wall stress increases with increasing ventricular radius but is inversely related to wall thickness.