Final answer:
For a cocaine-induced MI unresponsive to standard treatment, more aggressive measures like thrombolytics, angioplasty, and advanced cardiac support may be needed due to cocaine's vasoconstrictive effects which increase blood pressure and oxygen demand.
Step-by-step explanation:
When a cocaine-induced myocardial infarction (MI) does not improve with the usual treatments such as supplemental oxygen, aspirin, and nitroglycerine, the next step in management should be aimed at more aggressive interventions. Immediate attention may include the administration of thrombolytic agents, anticoagulants like heparin, and possibly invasive procedures like balloon angioplasty, stent placement, or bypass surgery. If the cardiac damage is severe, advanced options such as coronary replacement or the deployment of a coronary assist device may be considered. Cocaine causes vasoconstriction, which increases blood pressure by narrowing blood vessels and increasing resistance to blood flow. The management of a cocaine-induced MI can be challenging due to cocaine's potent vasoconstrictive effects, which exacerbate the oxygen demand-supply mismatch in the myocardium, making standard treatments less effective.