Rehfeldt, Kent H.

A 44-year-old recent heart transplant recipient supported by VA-ECMO presented to the operating room (OR) for left ventricular (LV) vent removal. She had a history of double-inlet LV with right atrioventricular valve atresia and transposition of great arteries, status post fenestrated Fontan complicated by end-stage heart failure. Three days ago, she underwent a fourth sternotomy and orthotopic heart transplant complicated by coagulopathy and severe bi-ventricular dysfunction necessitating initiation of central VA-ECMO. Due to massive blood product transfusion and ventricular dilatation, an apical LV vent was inserted. Postoperatively the arterial line waveform remained non-pulsatile. The patient was brought to the OR for mediastinal debridement and removal of the LV vent for the purpose of assessing ventricular function and improving arterial pulsatility. Pulse pressure remained negligible at an ECMO flow of 4.5 L/min. Transeosphageal echocardiography (TEE) demonstrated extensive thrombosis of the aortic root, particularly involving the right and non-coronary sinuses (Fig 1a). The aortic valve (AV) did not open. Patency of the left main coronary ostium was evident by color Doppler (Fig 1b) although no right coronary artery (RCA) flow could be visualized. The tip of LV vent was seen tenting the anterior leaflet of mitral valve (MV) causing significant regurgitation. (Fig. 2a-d) After vent removal, LV contraction gradually increased and the AV began to open. This progressively dislodged thrombus from the aortic root. At the conclusion of imaging, there was a highly mobile, bi-lobed thrombus attached to the sinotubular junction (Fig 1c-d). Right ventricular (RV) function remained severely reduced. Moderate mitral regurgitation persisted, arising from A2 leaflet prolapse. This patient subsequently underwent transcatheter thrombectomy and aspiration of the aortic root with cerebral protection device. Coronary angiogram confirmed proximal RCA occlusion (Fig. 3). Attempts to remove RCA thrombus were only partially successful. She eventually required a second heart transplant due to RV infarction. Discussion: This case illustrates a TEE-detected complication of excessive LV venting during VA-ECMO support, namely aortic root thrombosis associated with lack of AV opening. TEE also demonstrated the associated complications of RCA occlusion and iatrogenic mitral valve injury. Unfortunately, these complications were not detected soon enough to avoid RV infarction.

Magnetic gastroesophageal reflux devices are becoming a common treatment option for reflux refractory to medical therapy. These devices are inserted laparoscopically with successful outcomes; however, patients may still complain of dysphagia after implantation. Echocardiographers may be hesitant to perform transesophageal echocardiography (TEE) in these patients as esophageal surgery and dysphagia represent relative contraindications to performing TEE. However, we present 2 cases where intraoperative TEE was performed in patients with reflux devices without complication or image degradation. The described cases, in addition to a review of the perioperative management of these devices, support the use of TEE in this patient population.

AbstractBackgroundTransesophageal echocardiography (TEE) is a specialized form of cardiac ultrasound and has been associated with rare but serious complications. In patients with prior esophageal surgery, the risk of esophageal damage or the inability to perform a comprehensive and successful TEE warrants further evaluation.MethodsRetrospective study of patients with prior esophageal surgery who underwent TEE between June 21, 2002 and October 15, 2019. Medical and echocardiographic records were reviewed for image quality and procedural complications. Post‐procedure complications and 30‐day all‐cause mortality were collected. Evaluation by gastroenterology (GI), otolaryngology/ear, nose, throat (ENT), or thoracic surgery (TS) within 30 days of TEE was reviewed in detail.ResultsNinety‐five patients with prior esophageal surgery underwent 145 TEEs. The most commonly performed esophageal procedures were anti‐reflux operations (89%). TEE image quality was degraded in 16% while transgastric imaging was not completed in 37% of cases. A comprehensive TEE was completed in 57% of patients with diagnostic study goals achieved in 96% of cases. Comments describing procedural difficulty were reported in 6% while comments on procedural complications occurred in 1% of cases. Post‐procedure complications occurred in 1% of patients including hypotension and unplanned hospital/ICU admission.ConclusionsConcern for esophageal damage and the inability to perform a comprehensive and diagnostic TEE may limit the usefulness of TEE in patients with prior esophageal surgery. While TEE‐associated complications were rare in this series, a conservative approach with a thorough pre‐procedure assessment, including multi‐disciplinary evaluation when appropriate, is prudent in this complex cohort of patients.

Venoarterial extracorporeal membrane oxygenation (vaECMO) is a well-established treatment option for severe cardiogenic shock of various etiologies. Although trials have explored weaning strategies, a brief and conclusive overview is lacking. We present the different aspects of weaning and provide an evidence- and experienced-based guide for clinicians managing patients under vaECMO in the preweaning, weaning, and postweaning phases.

Utilization of venoarterial extracorporeal membrane oxygenation (VA-ECMO) is expanding, but dual VA-ECMO circuits to treat cardiogenic shock with refractory hypoxemia is unreported. We describe the case of combined cardiogenic and distributive shock due to necrotizing pulmonary blastomycosis. After initial central VA-ECMO cannulation, acute respiratory distress syndrome (ARDS) with increasing shunt resulted in significant central hypoxemia due to progressive ventilation-perfusion mismatch. An additional circuit provided complete oxygenation of the high circulating volume. After 4 months on support, he underwent successful heart-lung-kidney transplantation. Dual ECMO circuits are technically feasible and may be advantageous in specific circumstances of high pulmonary shunting resulting in excessive hypoxemia unbalanced with appropriate oxygen delivery.

Due to familiarity, short half-life, ease of monitoring, and the availability of a reversal agent, heparin remains the anticoagulant of choice for cardiac operations requiring cardiopulmonary bypass (CPB). However, occasionally patients require CPB but should not receive heparin, most often because of acute or subacute heparin-induced thrombocytopenia (HIT). In these cases, if it is not feasible to wait for the disappearance of HIT antibodies, an alternative anticoagulant must be selected. A number of non-heparin anticoagulant options have been explored. However, current recommendations suggest the use of a direct thrombin inhibitor such as bivalirudin. This review describes the use of heparin alternatives for the conduct of CPB with a focus on the direct thrombin inhibitors.

Diastolic mitral valve regurgitation is a rare phenomenon described in patients with atrioventricular conduction abnormalities, severe left ventricular systolic or diastolic dysfunction with regional wall motion dyssynchrony, or severe acute aortic valve regurgitation. The presence of diastolic mitral valve regurgitation in acute aortic regurgitation due to endocarditis suggests critical severity requiring urgent surgical valve replacement. We describe a case of diastolic mitral regurgitation in the setting of complex native mitral-aortic valve endocarditis in a patient in normal sinus rhythm and review the etiologic mechanisms of this phenomenon, echocardiographic assessment, and therapeutic implications for hemodynamic management.