Dr. Jetty Sedyawan, SpJP.K

Patients with Acute Coronary Syndrome / ACS include those whose clinical presentations cover the following range of diagnoses: unstable angina, non–ST-elevation myocardial infarction (NSTEMI), and ST-elevation myocardial infarction (STEMI). This ACS spectrum concept is a useful framework for developing therapeutic strategies. The initial diagnosis of ACS is based on history, risk factors, and, to a lesser extent electrocardiography (ECG) findings.

The symptoms are due to myocardial ischemia, the underlying cause of which is an imbalance between supply and demand of myocardial oxygen. To help improve the treatment of ACS, the American College of Cardiology (ACC) and the American Heart Association (AHA) developed guidelines for the diagnosis and management of these patients which were recently updated. A 12-lead ECG should be obtained within 10 min after first medical contact and immediately read by an experienced physician. Blood must be drawn promptly for troponin (cTnT or cTnI) measurement. The result should be available within 60 minutes. The test should be repeated after 6 to 12 hours if the initial test is negative

There are now five baseline therapies for all patients: aspirin, clopidogrel, anticoagulant, beta-blockers, and nitrates. The benefit occurred in acute treatment with clopidogrel within the first thirty days. Several anticoagulants are available, namely unfractionated heparin (UFH), Low molecular weight heparin (LMWH), fondaparinux . The choice depends on the initial strategy. Management strategies: urgent invasive, early invasive, or conservative strategies in the original guideline document. Furthermore, invasive treatment and glycoprotein IIb/IIIa inhibitors are best targeted with risk stratification, with the benefit conferred to the higher risk patients.

Aspirin is recommended for all patients presenting with NSTE-ACS without contraindication at an initial loading dose of 160 to 325 mg (non-enteric). An immediate 300 mg loading dose of clopidogrel is recommended, followed by 75 mg clopidogrel daily. If possible, urgent coronary angiography followed by revascularization (PCI or coronary artery bypass grafting [CABG]) in patients with intermediate to high-risk features is recommended, such as patients with refractory or recurrent angina associated with dynamic ST-deviation, heart failure, life threatening arrhythmias, or hemodynamic instability. ACE inhibitors are indicated long-term in all patients with left ventricular ejection fraction (LVEF) <40% and in patients with diabetes, hypertension, or chronic kidney disease unless contraindicated .

ACE inhibitors should be considered for all other patients to prevent recurrence of ischaemic events. Angiotensin Receptor Blockers (ARBs) should be considered in patients who are intolerant to ACE inhibitors and/or who have heart failure or MI with LVEF <40%. Since, lethal ventricular arrhythmias may develop abruptly in patients with STEMI, all patients should be monitored with ECG on arrival in the emergency room (ER). The more common approach today is routine prophylactic beta-blockers in the setting of acute MI, which reduces the incidence of VF. This practice is encouraged when appropriate.

Similarly, in terms of preventing arrhythmias, correction of hypomagnesemia and hypokalemia is encouraged because of the potential contribution of electrolyte disturbances to VF. Emergency room physicians must determine which patients should be admitted for more tests and observation and which patients can be discharged safely. Among those requiring hospitalization, physicians must also decide if the patient needs to be admitted to a specialty cardiology bed. In patients without recurrence of pain, normal ECG findings, and negative troponins tests, a non-invasive stress test for inducible ischaemia is recommended before discharge.

DR JETTY RH SEDYAWAN SpJP.K
“Symposium Trauma Intensive Care”  RSPAD- Borobudur Hotel, March 7-8, 2009