Final answer:
To reduce in-hospital and 30-day mortality in a patient with STEMI, reperfusion therapy such as thrombolytic therapy, PCI, or CABG is the most important intervention, alongside other treatments like anticoagulants and procedures to maintain vessel patency.
Step-by-step explanation:
The question pertains to the reduction of mortality rate in a patient presented with an ST-elevated myocardial infarction (STEMI). Immediate treatments for a myocardial infarction (MI) involve administering supplemental oxygen, aspirin, and nitroglycerin sublingually. However, to reduce in-hospital and 30-day mortality, reperfusion therapy is crucial which may include thrombolytic therapy, percutaneous coronary intervention (PCI), or coronary artery bypass grafting (CABG) depending on the patient's situation and time since symptom onset. Long-term, patients may require anticoagulants such as heparin and procedures like balloon angioplasty or the insertion of stents to maintain vessel patency. In severe cases, if the heart is extensively damaged, transplant or mechanical support with a coronary assist device may be considered.