Coronary artery disease associated with bicuspid aortic valve stenosis: an autopsy finding

Abstract

Forensic history:

Male, 50 years old, who according to the medico-legal history had a history of arterial hypertension; further information is unknown. He was found deceased in a public area, with a postmortem interval of 3 to 5 hours at the time of discovery. The cause of death was acute myocardial infarction, and the manner of death was natural. Relevant autopsy findings were:
1.Coronary atherosclerosis affecting the right, left, and anterior descending coronary arteries, with the latter showing approximately 95% luminal narrowing, without thrombosis (Figure 1).
2.Recent myocardial infarction in the left ventricle, approximately 24 hours in evolution, characterized by coagulative necrosis with fiber waviness, interstitial edema, and scarce inflammatory infiltrate (Figure 2).
3.Bicuspid aortic valve of the latero-lateral type with stenosis due to calcification (Figure 3).
4.Cardiac hypertrophy with concentric left ventricular hypertrophy (wall thickness of 2 cm).
The coexistence of coronary artery disease secondary to atherosclerosis and calcified aortic valve stenosis has been described, noting that both share common risk factors and pathogenic mechanisms. These include endothelial injury, lipid accumulation, chronic inflammatory response, calcification, and genetic factors¹²³.
Coronary artery disease is characterized by impaired blood flow in the coronary arteries, usually due to the formation of atherosclerotic plaque (atherosclerosis). This plaque may undergo thrombosis and lead to myocardial infarction (MI). In approximately 10% of patients, MI may occur without thrombosis and may be due to other causes, such as coronary vasospasm⁴. In the present case, coronary atherosclerosis was observed, involving the right, left, and anterior descending coronary arteries (LAD), with the latter showing approximately 95% luminal narrowing, without thrombosis. It has been reported that coronary occlusion involving 70% of the vessel’s transverse lumen may cause tissue ischemia⁴.
In the case described here, a recent myocardial infarction was found in the area supplied by the LAD, specifically the anterior wall of the left ventricle.
Regarding the bicuspid aortic valve (BAV), it is characterized by the aortic valve having two leaflets instead of three. It is considered the most common congenital heart disease, with an estimated prevalence of 0.5% to 2% in the general population. It may remain asymptomatic and be identified incidentally, or it may present with symptoms when complications occur, either valvular (stenosis, insufficiency, endocarditis) or aortic (aneurysm, dissection). One of the most common complications is valvular dysfunction due to calcific stenosis or insufficiency⁵.
Stenosis leads to restriction and obstruction of the valve, causing compensatory hypertrophy of the left ventricle, which, depending on severity, may progress to heart failure⁶. In the present case, the bicuspid aortic valve was of the latero lateral type (according to the classification proposed by Michelena)⁷, with stenosis due to calcification and evidence of cardiac hypertrophy at the expense of the left ventricle. This occurred in a male under 65 years of age, which is consistent with the literature, as BAV is more common in men and tends to develop calcification more rapidly than in patients with tricuspid stenotic valvulopathy⁵.
Given that this was a sudden death in a public area, the performance of an autopsy is of particular importance to determine the cause and manner of death.