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Case 2: 63-year old woman presented with central chest pain of two hours duration. On examination her blood pressure was 90/60 mm Hg, she had a weak pulse, distended neck veins with elevated jugular venous pressure, normal first and second heart sounds and lung fields were clear on auscultation. |
Ragavendra
R. Baliga, M.D
Assistant
Professor
Division
of Cardiology
University
Of Michigan
Question 15 of 17:
Most patients with proximal right coronary artery occlusion have hemodynamically significant right ventricular infarction.
You clicked 'False'
Correct!
Most patients with proximal right coronary artery occlusion do not have hemodynamically significant right ventricular ischemia (1). Factors likely to explain these features include
a) Myocardial oxygen demand of the right ventricle is significantly less than that of the left ventricle because the lower resistance in the pulmonary circuit results in a much smaller RV muscle mass than the left ventricle (2).
b) The right-ventricle has a more favorable oxygen supply-demand ration than the left ventricle, because of the more extensive collateral flow from the left to the right ventricle (3,4).
c) Coronary perfusion of the right ventricle occurs in both systole and diastole (2).
References:
1. Setaro JF, Cabin HS. Right ventricular infarction. Cardiol Clin 1992;10:69-90
2. Lee FA. Hemodynamics of the right ventricle in normal and diseased states. Cardiol Clin 1992;10:59-67
3. Cross CE. Right ventricular pressure and coronary flow. Am J Physiol 1962;202:12-16
4. Haupt HM, Hutchings GM, Moore GW. Right ventricular infarction: role of the moderator band artery in determining infact size. Circulation 1983;67:1268-1272.
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