Report
A 39-year-old, previously healthy male of Black African ethnic origin presented to the Emergency Department on the 25th of April 2020 with fever and abdominal pain after a recent viral illness. Chest radiographs showed typical ground-glass changes indicative of viral pneumonia (Fig. 1A). A computer tomography (CT) scan showed acute pancreatitis, small bilateral pleural effusions, lung consolidation, associated reactive lymphadenopathy and features indeterminate for COVID-19 (Fig. 1B). Echocardiography revealed significant impairment of biventricular function. Nasal and pharyngeal swabs, bronchoalveolar lavage fluid, and sputum were tested for common respiratory viruses, and the results were all negative. Two SARS-CoV-2 antigen swab tests were also negative. He was referred to our team for emergency assessment with a view to mechanical circulatory support.
The patient arrived intubated and ventilated, with a temperature of 38.3oC. He required an FiO2 of 1.0 and his peak airway pressure was > 35 cmH2O. He was receiving high-dose vasopressors and inotropes and the clinical picture was one of severe acute cardiopulmonary failure. He had a blood picture in keeping with hyperinflammation, with a serum ferritin of 2316 μg.l-1 and a CRP of 424 mg.l-1. His Troponin T was 616 ng.l-1 and his fibrinogen was 8.83 g.l-1. He was taken straight to the operating theatre for a transoesophageal echocardiographic examination with a view to BiVAD implantation. This confirmed severe biventricular failure(Video 1) with an ejection fraction of 0.31, and with no structural intra-cardiac lesions or abnormalities.
Extracorporeal biventricular assist device therapy with two CentriMag™ pumps was established following median sternotomy. Right heart bypass was achieved using a 32Fr Medtronic DLP® malleable single-stage cannula secured to the right atrium and returned to the patient via a 24F EOPA® arterial cannula (pulmonary artery cannula). Left heart bypass was achieved by inserting a CentriMagTM 34Fr Drainage cannula in the left ventricular apex and returned to the patient via a 24F EOPA® arterial cannula (aortic cannula) (Video 2). We were unable to take myocardial biopsies intra-operatively due to the urgency of the procedure. An extracorporeal membrane oxygenator (sweep 1:1) was included in the left sided circuit due to deteriorating lung function. He was subsequently placed on lung rest settings (inspiratory pressure 20 cmH2O, PEEP 10 cmH2O, respiratory rate of 10 min-1). The flow rates on each circuit were set to 2.2 l.min-1.m-2 and the acidosis and serum lactate levels resolved over the next 12 hours.
The patient was reexplored with the evacuation of a pericardial haematoma on postoperative day 4. On postoperative day 11, a CT brain scan detected an intraparenchymal haemorrhage in the left parietal lobe deep white matter with cyst surrounding vasogenic oedema. There was no midline shift. A repeat CT brain on postoperative day 37 showed complete resolution of the haemorrhagic component and residual focal low attenuation.
By postoperative day 17, he had stabilised on the ventilator with good tidal volumes, and the oxygenator was removed from the left side of the circuit. He underwent a percutaneous tracheostomy on postoperative day 22 as per national guidelines [7]. On postoperative day 33, SARS-CoV-2 antibody tests became widely available in the UK, and he tested positive. He continued to make good progress; lung compliance returned to normal with improving ventilation and oxygenation (Fig. 1C), and his BiVAD circuits were explanted on postoperative day 44, with the heart supported on milrinone for 48 hours (Video 3) .
On postoperative day 50, the patient was sitting out of bed but still ventilator dependent on continuous positive pressure ventilation via a tracheostomy. He had global peripheral muscle weakness but was progressing well with physical therapy. He transferred out to a step-down unit in another hospital for continued rehabilitation (Fig. 1D).