Khan, HMW., Rudd, A., Gamble, D., Mezincescu, AM., Cheyne, L., Horgan, G.W., Dhaun, N., Newby, DE. and Dawson, D.
Journal of the American Heart Association 2022(11), e025989.
cardiomyopathy, takotsubo, renin, angiotensin, endothelin
||BACKGROUND: We investigate if renin--angiotensin and endothelin--1 response pathways follow the same pattern of recovery as
left ventricular ejection fraction in patients with takotsubo cardiomyopathy.
METHODS AND RESULTS: Ninety patients with takotsubo cardiomyopathy (n=30 in each of "acute," "convalescent" [3[symbol]-5 months]
and "recovered" [>1 year] groups) who were on minimal or no medication and were free of any significant cardiac/metabolic
comorbidities, and 30 controls were studied. Serum concentrations of renin, angiotensin--converting enzyme, angiotensin II,
big endothelin--1, endothelin--1 were measured using commercially available ELISA, and B--type natriuretic peptide was meas-
ured using an immunoassay. Mean left ventricular ejection fraction was <40% during the acute phase in all groups, but recov-
ered to 63% in convalescent and 64% in the recovered groups, respectively. Serum renin concentrations remain persistently
elevated after a episode of takotsubo cardiomyopathy (P=0.03 versus controls). Angiotensin converting enzyme levels are
significantly depressed during the acute phase compared with convalescent (P=0.004), recovered takotsubo cardiomyopathy
(P=0.02) or controls (P=0.03). Angiotensin II is increased in patients with takotsubo cardiomyopathy (P<0.001 versus controls)
remaining persistently elevated in the chronically recovered group alone (P=0.03 versus controls). Big endothelin--1 levels are
unchanged, but endothelin--1 is significantly lower after takotsubo cardiomyopathy compared with controls (P=0.03).
CONCLUSIONS: Despite "normalization" of the left ventricular ejection fraction, there is long--term maladaptive activation of renin--
angiotensin system in patients with takotsubo cardiomyopathy.