2 | Case report
A 51-year-old man was trapped in a closed sewage tank for about 20
minutes during his project on August 6. He was in coma when pulled out
without electrocardiographic abnormality(Figure 1A). Endotracheal
intubation, and pure oxygen inhalation were arranged immediately. The
patient has no significant medical background or family history. After
treatment, His consciousness became clear gradually. However,
electrocardiogram showed extensive elevation of ST segment (Figure
1B)and myocardial enzyme index were increased dramatically on August
8th. What’s more, ventricular fibrillation occurred on
August 9th. Luckily, sinus rhythm and consciousness
was restored about one minute after cardiopulmonary resuscitation. No
obvious abnormality was found in coronary computed tomographic
angiography (CTA), but pluse indicator continuous cardiac output (PICCO)
suggested low cardiac output with 1.9L/min/m2 of the
cardiac index (CI).
Cardiotonic drugs like levosimendan were not effective, so intra-aortic
ballon pump (IABP) was implemented then. The ST segment decreased to
normal with left ventricular ejection fraction(EF) increased to 46% on
August 13th and then the IABP was removed. However, he
slipped back into a coma with ST segment elevated and EF decreased to
31% again afterwards. So veno-arterial extracorporeal membrane
oxygenation (VA-ECMO) was implemented. Two days later, his ST segment
elevated again (Figure 1C) with extremely bad heart function (Movie
S1).Coronary angiography(CAG) found no stenosis but cardiomyocyte
hypertrophy was showed in the pathology of myocardial biopsy(Figure 2A)
and mitochondrial swelling, dissolution as well as vacuolization were
observed under electron microscopy(Figure 2B). In order to support heart
function powerfully, we put IABP to cooperate with VA-ECMO.
After about 2 weeks’ support of V-A ECMO and 3 of IABP, his heart
function gradually returned to normal without any support(Figure
1D,Figure 3, Figure 4).