A 45-year-old man is diagnosed with dilated nonischemic cardiomyopathy. Late gadolinium enhancement cardiac magnetic resonance (CMR) imaging shows a left ventricular ejection fraction (LVEF) of 20% and evidence of extensive midwall myocardial scarring. A recent study determined prognosis in patients with dilated cardiomyopathy using CMR-derived LVEF and evidence of midwall myocardial scarring (fibrosis). Two models were assessed: one model was based on LVEF alone, and the other incorporated the presence or absence of fibrosis. The following 5-year prediction curves were reported: Based on the study results, what is the approximate predicted 5-year all-cause mortality for this patient?
A)10%
B)20%
C)30%
D)40%
E)50%

Question

A 45-year-old man is diagnosed with dilated nonischemic cardiomyopathy.  Late gadolinium enhancement cardiac magnetic resonance (CMR) imaging shows a left ventricular ejection fraction (LVEF) of 20% and evidence of extensive midwall myocardial scarring.  A recent study determined prognosis in patients with dilated cardiomyopathy using CMR-derived LVEF and evidence of midwall myocardial scarring (fibrosis).  Two models were assessed: one model was based on LVEF alone, and the other incorporated the presence or absence of fibrosis.  The following 5-year prediction curves were reported:  Based on the study results, what is the approximate predicted 5-year all-cause mortality for this patient?
A)10% 
B)20% 
C)30% 
D)40% 
E)50%

Quizplus · Accepted Answer

Explanation: 11ec2b69_c0eb_9dd4_8f63_bff8a7e3bdf5_MD0005_00 In these prediction curves, the 5-year risks of mortality or cardiac transplantation were calculated based on the left ventricular ejection fraction (LVEF) derived from cardiac magnetic resonance imaging and on the presence or absence of fibrosis (myocardial scarring). The dotted purple curve was constructed based on information about LVEF alone; the red and dotted blue curves additionally incorporated information about the presence or absence of fibrosis. The top chart provides the risk of all-cause mortality and the bottom chart provides the risk of cardiovascular mortality or transplantation. The top chart is the appropriate choice for all-cause mortality calculations. Given the presence of fibrosis (red curve) and a LVEF of 20% (x-axis), the 5-year all-cause mortality risk (y-axis) was 40%. A patient with LVEF of 20% and no fibrosis had an all-cause mortality risk of about 20% (dotted blue line in top chart) (Choice B). In the absence of information regarding presence or absence of fibrosis, the all-cause mortality risk of a patient with LVEF 20% was about 30% (dotted purple curve in top chart) (Choice C). Thus, the additional knowledge regarding the presence or absence of fibrosis changed mortality estimates. This may be useful in risk classification of patients with heart failure. (Choice A) The approximate 5-year risk of all-cause mortality for a patient with LVEF of 30% (rather than 20%) and absence (rather than presence) of fibrosis was about 10% (dotted blue curve in top chart). (Choice E) The approximate 5-year risk of cardiovascular mortality or transplantation (rather than all-cause mortality) for a patient with a LVEF of 20% and history of fibrosis was about 50%. Educational objective: Mortality prediction curves are useful for providing mortality risk while accounting for a number of variables. To interpret these curves correctly, each variable must be accounted for to arrive at the accurate predicted mortality.

A 45-Year-Old Man Is Diagnosed with Dilated Nonischemic Cardiomyopathy