Thread by @drgrahamcole

How is the #heart affected in severe #COVID19? Patients with a raised troponin have worse outcomes – but why? Our multicentre #whyCMR @ESC_Journals paper shows a variety of problems including infarction, ischaemia and a myocarditis-like injury. academic.oup.com/eurheartj/adva…

This was a very sick #COVID19 group: all admitted, all with raised troponin, 1 in 3 ventilated. Our findings DON’T tell us about the hearts of patients with mild illness who didn’t need admission to hospital or didn’t have raised troponin.

Even pre #COVID19 (remember that?) #whyCMR was useful to find the cause and implications of troponin elevation. Check out this paper from @DeepDastidar and @SCMRorg CEO @chiarabd sciencedirect.com/science/articl…

In our paper we applied #whyCMR techniques to patients who had survived an admission with severe #COVID19 and elevated troponin. Around 1 in 4 patients had infarcts and/or ischaemia.

Around 1 in 4 had a #myocarditis LIKE pattern of injury. Note we say myocarditis-LIKE – we don’t yet know what is causing this, but it looks similar to myocarditis we are familiar with before #COVID19.

Some had a mixture of infarct, ischaemia and myocarditis-like findings (see below). But around HALF of patients had NO MAJOR ABNORMALITY. We think this is important: even in a group who had been very sick with raised troponin it was common to find no evidence of heart damage.

Even in those with an abnormality, it was usually small (9 out of 10 patients had normal heart function). And of those with a myocarditis-like injury, 7 out of 10 had no #whyCMR evidence of ongoing activity by the time we scanned them.

It’s only right to mention some limitations. Survivor bias (we could only scan those who survived) and referral bias – we didn’t scan frail patients where the clinician felt #whyCMR was unlikely to inform management.

Also, it’s known that #whyCMR picks up asymptomatic myocardial damage (both infarct and myocarditis-like) and we saw this in our control group. Although some of the post #COVID19 abnormalities were clearly acute, it is likely that some were pre-existing disease.

So in summary – #whyCMR identifies multiple patterns of cardiac injury seen following #COVID19. It may take years to know what this means in terms of prognosis, but the abnormalities are often subtle, even in this group recovering from severe illness.

Thanks to co-authors @dr_tkot @yousuf9021 @DrKartikKumar @kavitha_varan @GD_Thornton @RishiPatel06 @chacko_liza @CardioJames @CLCoyle7 @gabycaptur @tobyhillman

@HelpMyBreathing @BeingJeetley @PrapaKanagarat1 @onnmin @dr_manisty @CardiologistUK @KellmanPeter @JccmoonMoon @ThomasTreibel @dr_m_fontana

And thanks to our funders and institutions @TheBHF @NIHRresearch @RoyalFreeNHS @NHSBartsHealth @ucl @UCL_ICS @UCLHresearch @ImperialBRC
@imperialcollege @ImperialNHLI @ImperialNHS