Acute Right Ventricular Failure and Right-to-Left Shunt Due to Massive Coronary Air Embolism Following MitraClip.

An 83-year-old woman was admitted to our centre for symptomatic mitral regurgitation caused by P2 prolapse. On preprocedural echocardiography, the left ventricular ejection fraction was 68%, and neither right ventricular dysfunction nor pulmonary hypertension was detected (Fig. 1A-C; Videos 1 and 2 , view videos online). Although a significant lesion was found in the left anterior descending (LAD) artery on coronary angiography (Supplemental Fig. 1), no significant lesion was found in the right coronary artery (RCA) (Video 3 , view video online). Given the high surgical risk caused by an ongoing refractory heart failure, chronic severe renal insufficiency, poor mobility, and chronic respiratory disease (EuroSCORE-II, 12.28%), percutaneous coronary intervention (PCI) to the LAD and MitraClip (Abbott Laboratories, Chicago, IL) were recommended by our heart team. A week after the PCI (Supplemental Fig. 1), MitraClip was successfully performed under heparin monitored by activated coagulation time (> 250 seconds). After removal of the clip delivery system (CDS) with continuous aspiration with a 50-cc syringe, the patient developed hypotension and complete atrioventricular block, and the O2 saturation decreased from 96% to 48%. Although the hemodynamics were stabilized by 100% oxygen and catecholamines, an echocardiogram revealed a massive right-to-left shunt where the system was inserted, complicated by severe tricuspid regurgitation (Fig. 1D, E; Videos 4 and 5 , view video online) and enlarged right atrium (Fig. 1D [arrowheads]) and ventricle. Coronary angiography was performed from the left femoral access because of an inferior ST elevation and showed a to-and-fro coronary flow at the mid-portion of RCA, suggesting an air embolization (Fig. 1F; Video 6 , view video online). Following several attempts of air aspiration with 6-Fr Export AP aspiration catheter (Medtronic, Irvine, California USA), the coronary flow was restored (Fig.1G, H), the right heart function gradually improved, and the shunt turned out to be left-to-right (Fig.1I; Video 7 , view video online). Thereafter, the vital sign was stable, and a postprocedural computed tomography revealed a small amount of air in the right atrium without any signs of systemic embolism. A peak troponin level of 4267.7 ng/L was identified on day 1. The patient was discharged home on day 36.