TNNT2 and myocardial infarction: Zhu et al. [8] separated 49 autopsy cases into freshwater drowning, saltwater drowning, and acute myocardial infarction, and analyzed serum Na, Cl, Mg, calcium (Ca), blood urea nitrogen (BUN), creatinine (Cr), pulmonary surfactant-associated protein A (SP-A) and cardiac troponin T (cTN-T).