A 56-year-old man is admitted to a tertiary care center after being involved in a high-speed motor vehicle accident. The patient was thrown from his vehicle and suffered severe head trauma along with multiple fractures involving his ribs and extremities. Despite aggressive treatment, he dies the following day from massive cerebral edema and brainstem herniation. Autopsy shows the following heart findings:Left atrium: enlarged
Left ventricular myocardial mass: increased
Left ventricular wall thickness: increasedThe structural changes observed in this patient's heart are most likely associated with which of the following conditions?

Question

A 56-year-old man is admitted to a tertiary care center after being involved in a high-speed motor vehicle accident.  The patient was thrown from his vehicle and suffered severe head trauma along with multiple fractures involving his ribs and extremities.  Despite aggressive treatment, he dies the following day from massive cerebral edema and brainstem herniation.  Autopsy shows the following heart findings:Left atrium: enlarged
Left ventricular myocardial mass: increased
Left ventricular wall thickness: increasedThe structural changes observed in this patient's heart are most likely associated with which of the following conditions?

Quizplus · Accepted Answer

11ec160b_38e2_02f3_9249_c1e647190809_MD0001_00 The autopsy findings of this patient's left ventricle (LV) are consistent with concentric hypertrophy most likely due to chronic hypertension. LV hypertrophy is generally defined as an increase in the left ventricular mass due to increased wall thickness (concentric) or cavity size (eccentric). Concentric hypertrophy is characterized by uniform thickening of the ventricular wall with the outer dimensions of the ventricle remaining almost unchanged, resulting in a narrowed ventricular cavity size. It is due to chronic elevation of ventricular pressures during systole, which is usually caused by long-standing hypertension or aortic stenosis (increased LV afterload). Patients may develop diastolic dysfunction with left atrial enlargement and congestive heart failure due to impaired ventricular compliance and filling. (Choice A) An atrial septal defect causes a shunting of blood flow from the left to right atrium. This typically results in volume overload of the right ventricle, producing right atrial enlargement and eccentric (dilated) right ventricular hypertrophy. (Choice C) Mitral insufficiency causes LV volume overload as regurgitant flow through the mitral valve during systole increases the amount of blood returning to the LV during diastole. The net structural consequence of mitral insufficiency is enlargement of the LV cavity and eccentric hypertrophy. (Choice D) Mitral stenosis leads to left atrial enlargement due to elevated pressure in the left atrium. The LV cavity is typically small/normal in size with normal wall thickness due to restriction of blood flow across the mitral valve. (Choice E) Aging is associated with a decrease in LV chamber size, predominantly through shortening of the apex-to-base dimension accompanied by a leftward bowing of the lower interventricular (sigmoid) septum. The aortic valve may also become calcified, resulting in aortic stenosis; however, structural cardiac changes due to aging are generally not prominent before age 65. (Choice F) The ventricular remodeling that occurs after an acute myocardial infarction involves expansion, thinning, and fibrous healing of the infarcted zone of myocardium. Regional dysfunction of the infarcted myocardium causes volume overload for the remaining viable myocardium. The net result is usually eccentric hypertrophy, with enlargement of the LV cavity. (Choice G) Patients with Wolff-Parkinson-White syndrome have an accessory pathway that bypasses the atrioventricular node and directly connects the atria and ventricles. This results in ventricular preexcitation and the development of tachyarrhythmias. The LV usually appears grossly normal. Educational objective: Concentric hypertrophy is characterized by uniform thickening of the ventricular wall and narrowing of the ventricular cavity due to increased afterload (eg, chronic hypertension, aortic stenosis). Eccentric hypertrophy is characterized by reduced ventricular wall thickness with an associated increase in chamber size due to volume overload. __________ References: The progression of hypertensive heart disease. (http://www.ncbi.nlm.nih.gov/pubmed/21263005)

A 56-Year-Old Man Is Admitted to a Tertiary Care Center