Triphasic mitral inflow in acute coronary syndrome: A case study

An 86-year-old woman was referred to our hospital for the management of rapid onset of chest pain. Blood analysis showed increased levels of cardiac enzymes and B-type natriuretic peptide. An electrocardiogram showed poor R wave in precordial leads and a QS wave in lead V4. A chest roentgenogram showed mild pulmonary congestion. An echocardiogram showed hypokinesis of the broad anterior wall of the left ventricle (LV). A pulsed Doppler echocardiogram of mitral inflow revealed an abnormal relaxation pattern. After increasing the preload by leg elevation, an intermittent triphasic mitral inflow pattern emerged. The patient underwent emergent cardiac catheterization for acute coronary syndrome (ACS). A pressure study after leg elevation disclosed an elevation in LV diastolic pressure and a "dip-up-down pattern." The patient underwent percutaneous coronary intervention of the left anterior descending artery. This case showed that a triphasic mitral inflow pattern is observed not only in hypertrophic diastolic heart failure but also in ACS. The triphasic pattern may be observed in the case of low LV distensibility and markedly increased preload. This is the first case report describing triphasic mitral inflow in ACS and demonstrating the pathophysiology of a triphasic mitral inflow pattern.