Case presentation
Case 1: A 61-year-old man presented to another hospital with hypotension and hypoxia. Electrocardiography (ECG) revealed an elevated ST segment in I and aVL, and ultrasonic echocardiography (UCG) showed moderate MR due to mitral valve prolapse (MVP). The patient was transferred to our hospital due to CGS. On arrival, arterial blood gas (ABG) analysis revealed a pH of 6.95, pO2 of 59.8 mmHg, pCO2 of 80.9 mmHg, HCO3 level of 17.0 mEq/L, and lactate concentration of 12.4 mmol/L on the oxygen face mask at 10 L, and the patient’s blood pressure (BP) was 123 mmHg with a heart rate (HR) of 145 beats/min. The patient was immediately intubated. Chest radiography (CXR) revealed significant PLE (Figure 1A). V/AECMO was established between the right femoral vein (FV) and artery (FA) because systolic BP dropped below 40 mmHg. UCG revealed anterior MVP with anterolateral PMR (Figure 1C). Emergency coronary angiography (CAG) showed occlusion of the high-lateral branch (Figure 1B). We inserted the Impella CP device from the left FA for further hemodynamic support and LV unloading as a bridge to emergent surgery. Emergent MVR was performed. Cardiopulmonary bypass (CPB) with moderate hypothermia was established between the ascending aorta and bicaval venous cannulation. Aortic cannulation and aortic venting were positioned as far as possible to the distal ascending aorta to avoid clamping the motor of the Impella (Figure 1D). V/AECMO flow was decreased from 2.5 L/min to 0.6 L/min, and the Impella performance level (ImPL) was decreased from P6 to P2 after CPB initiation (Figure 2). After the ascending aorta carrying the Impella catheter was clamped using a soft joe aortic clamp, antegrade cold crystalloid cardioplegia (CCP) was administered, and the ImPL was reduced to surgical mode (P0). The heart immediately arrested. Although additional suction into the LV vent was required because of Impella-induced aortic regurgitation (AR) (Figure 1E), MVR could be performed safely. During de-airing of the LV, Impella was reestablished at ImPL P1. CPB was weaned with moderate doses of inotropic agents and sufficient oxygenation (Figure 2), and V/AECMO and Impella were removed. Prophylactic IABP was performed on the left FA. The patient was discharged uneventfully 3 weeks after surgery.
Case 2: An 81-year-old woman was transferred to another hospital with syncope and hypotension. ECG showed a depressed ST segment in II, III, aVF, and V2-6. Emergency CAG revealed severe stenosis of the left anterior descending branch and left circumflex (LCx). Percutaneous coronary intervention using a drug-eluting stent was performed on the LCx as the culprit lesion (Figure 3B, C). However, the patient developed severe respiratory failure and shock, which were managed using airway intubation, inotropic agents, and IABP. The patient was transferred to our hospital due to CGS. On arrival, ABG analysis revealed a pH of 7.150, pO2 of 71.1 mmHg, pCO2 of 29.2 mmHg, HCO3 level of 10.2 mEq/L, and lactate concentration of 11.4 mmol/L on mechanical ventilation at FiO2 100%, and the patient’s BP was 62 mmHg with a HR of 95 beats/min with shock dose inotropic agents. UCG revealed posterior MVP with anterolateral PMR (Figure 3D). V/AECMO was immediately established through the right FA and FV. We escalated the MCS from IABP to Imeplla CP for LV unloading because CXR revealed significant PLE (Figure 3A). Emergent MVR was performed using the same management as in Case 1 (Figure 4). V/AECMO and Impella were removed during surgery, and prophylactic IABP was performed from the left FA. The patient was discharged uneventfully 2 weeks after surgery.