Paradoxical Heart Failure Precipitated by Profound Dehydration: Intraventricular Dynamic Obstruction and Significant Mitral Regurgitation in a Volume-Depleted Heart
A 59 year-old Asian female presented with dyspnea (New York Heart Association class III/IV) which had developed and became aggravated over past several days. The patient had medical histories of old cerebrovascular accident and epilepsy. She hemodyhad not taken any food or water for a week due to long-standing anorexia and vomiting associated with her brain disease. Vital signs were notable with regard to hypotension (80/50 mm Hg) and tachycardia (heart rate: 110/min). On physical examination, she appeared tachypneic (respiratory rate: 20/min) with decreased skin turgor and a dry tongue. On auscultation, a systolic murmur (grade IV/VI) was audible at the left lower sternal border. Of note, chest radiography revealed newly developed pulmonary congestion (), which was unexpected. A 12-lead electrocardiography examination showed sinus tachycardia and nonspecific changes of ST-segment and T-wave. Laboratory findings revealed high plasma osmolality (388 mOsm/kg), hypernatremia (plasma sodium concentration: 167 mEq/L), uremia (blood urea nitrogen was 79.5 mg/dL) and increased plasma creatinine level (2.4 mg/dL), which were all suggestive of systemic dehydration. Hemoglobin was decreased to 8.4 g/dL. Serum protein was 7.6 g/dL and albumin was 3.2 g/dL.\nThe patient underwent transthoracic echocardiography for further evaluation of systolic murmur and cardiac pathology potentially associated with hemodynamic instability and pulmonary edema. Results showed SAM and incomplete coaptation of the MV (). And the left ventricular (LV) cavity was small (LV end-diastolic dimension: 39 mm) with notable hyperdynamic LV contraction (LV ejection fraction: 78%), suggesting intracardiac volume depletion. Although severe asymmetrical or concentric LV wall hypertrophy was not evident, relative wall thickness was 0.46 and LV mass index was 94 gm/m2, and those values corresponded to concentric remodeling of the LV (). Color Doppler evaluation showed significant eccentric MR caused by SAM of the MV (vena contracta width: 0.8 cm, effective regurgitant orifice: 0.6 cm2 and regurgitant volume: 60 mL, calculated with proximal isovelocity surface area method); however, MV itself was otherwise normal (). Continuous Doppler study of the LVOT showed a late-peaking profile of the flow with a maximal pressure gradient of 119 mm Hg estimated by systolic blood flow velocity, and it was suggestive of significant dynamic LVOT obstruction (). Meanwhile, early diastolic mitral inflow velocity (E) was 0.9 m/s and early diastolic mitral annulus velocity (E') at the septal corner was 0.04 m/s (E/E' ratio: 23). Inferior vena cava diameter was 1.1 cm and also showed good collapsibility (respiratory variability was above 50%).\nDespite pulmonary edema on the chest radiography, we decided to restore the patient's systemic volume, because the cause of pulmonary congestion was not due to absolute systemic volume overload, but due to intracardiac volume maldistribution resulting from SAM of the MV in the volume depleted heart. After receiving fluid therapy with crystalloid and other nutritional support for five days, the patient's condition stabilized and laboratory findings gradually returned to normal. Echocardiographic evaluation performed after treatment revealed complete resolution of SAM of the MV and disappearance of the preexisting dynamic LVOT obstruction and significant MR (). At the same time, E/E' ratio was decreased to 13, indicating reduced left atrial (LA) pressure compared to previous study. On hospital day 38, the patient was discharged in good condition.