What is the recommended waiting period before undergoing a stress test after the EKOS (Endovascular Katheter-directed Thrombolysis using the EKOS system) procedure?

Timing of Stress Testing After EKOS Procedure

For patients undergoing EKOS who are clinically stable without ongoing ischemic symptoms, stress testing should be performed 3-7 days after the procedure. 1

Clinical Context and Prerequisites

The timing of stress testing after EKOS depends critically on the indication for the procedure and the patient's clinical stability:

• If EKOS was performed for acute coronary syndrome or cardiac ischemia, stress testing should occur 3-7 days after stabilization when pursuing a conservative management strategy without planned angiography. 1

• If EKOS was performed for pulmonary embolism or deep vein thrombosis, the same 3-7 day window applies for clinically stable patients based on post-acute coronary syndrome management principles. 1

• The diagnostic and prognostic values of stress tests at 3-7 days versus 1 month are similar, but earlier testing identifies approximately half of all adverse events that occur during the first year. 1

Mandatory Prerequisites Before Proceeding

Before scheduling stress testing, verify the following conditions are met:

• No recurrent symptoms or ongoing ischemia 1
• Hemodynamic stability (no heart failure or serious arrhythmias) 1
• Normal or stable cardiac biomarkers 1
• Patient has been asymptomatic for 12-24 hours if unstable angina, or 2-5 days if NSTEMI 2

Selection of Stress Test Modality

Standard exercise ECG is the most reasonable initial test for patients who can exercise and have an interpretable resting ECG. 1

Stress imaging should be used when:

• Baseline ECG abnormalities exist (ST changes, bundle-branch block, LV hypertrophy, paced rhythm, pre-excitation, digoxin use) 1
• Previous revascularization has been performed 1
• Exercise ECG results are equivocal 1
• Patient cannot exercise adequately 1

For patients unable to exercise, pharmacological stress testing with dobutamine echocardiography or vasodilator nuclear imaging should be performed, with sensitivity ranging from 71-97% for detecting coronary artery disease. 1

Critical Timing Considerations Based on Intervention Type

If the patient underwent coronary intervention in conjunction with EKOS:

• After balloon angioplasty: Wait >2 weeks before stress testing, continue aspirin 1
• After bare-metal stent: Wait >4 weeks, continue dual antiplatelet therapy for at least 4 weeks 1
• After drug-eluting stent: Wait 6 months for new-generation DES or 12 months for old-generation DES 1

Antiplatelet Management During This Period

Continue aspirin indefinitely for patients on dual antiplatelet therapy following any coronary intervention. 1

Continue clopidogrel for at least 1 month and ideally up to 1 year. 1

Anticoagulant therapy should be continued for the duration of hospitalization (up to 8 days), then discontinued. 1

Common Pitfalls to Avoid

• Do not perform stress testing in patients with extensive comorbidities (liver or pulmonary failure, cancer) where risks outweigh benefits. 2
• Do not delay stress testing beyond 7 days in stable patients, as this misses the opportunity to identify early adverse events. 1
• Do not use standard exercise ECG in patients with baseline ECG abnormalities, as this significantly reduces accuracy. 1
• Do not proceed with stress testing if the patient has recurrent ischemic symptoms, as these patients require urgent angiography instead. 2