Effect of acute phase heart rate on long-term prognosis of patients with acute myocarditis: a single-centre retrospective study

AIM To investigate the effect of heart rate on the long-term prognosis of acute myocarditis.

METHODS Clinical data of 138 hospitalized patients with acute myocarditis from January 2017 to July 2022 were retrospectively collected and the patients were divided into MACE and non-MACE groups according to the follow-up results after discharge. Clinical characteristics, laboratory test results, electrocardiogram and echocardiogram of the two groups were compared, logistic regression was applied to analyze the risk factors for the occurrence of MACE in patients with acute myocarditis and ROC curves were applied to evaluate the predictive efficacy of heart rate indicators for the development of MACE.

RESULTS The median of follow-up was 34 (13, 53) months. In the MACE group, age, severe myocarditis, white blood cell count, mean heart rate at discharge and maximum heart rate at discharge were independent risk factors for the development of MACE in patients with acute myocarditis, compared with those in the non-MACE group (P<0.05, P<0.01). ROC curve analysis showed that the area under the ROC curve for mean heart rate at discharge was 0.818 (95% CI: 0.737～0.899), with a best cut-off value of 78.31, a sensitivity of 76.2% and a specificity of 77.1%. The area under the ROC curve for maximum discharge heart rate was 0.699 (95% CI: 0.599～0.798), with a best cut-off value of 96.5, a sensitivity of 69.0% and a specificity of 62.5%.

CONCLUSION Mean heart rate at discharge and maximum heart rate at discharge are the influential factors for prognosis of patients with acute myocarditis and they can be used as predictors of the development of MACE in the distant future.