Jin-Sup Park

The effect on periprocedural myocardial infarction of intra-coronary nicorandil prior to percutaneous coronary intervention in stable and unstable angina

BACKGROUND Intravenous nicorandil infusion dilates the coronary artery and reduces inflammation, coronary spasm, and arrhythmia. Periprocedural myocardial infarction (PMI) is a frequent and prognostically important complication of percutaneous coronary intervention (PCI). This prospective randomized study was designed to evaluate the efficacy of intracoronary nicorandil on PMI after elective PCI. METHODS AND RESULTS Eighty-one patients with stable or unstable angina undergoing PCIs of the left anterior descending artery were randomly assigned to the nicorandil group (n=41) or the control group (n=40). In the nicorandil group, 4 mg of intracoronary nicorandil was infused prior to PCI. Post-PCI, peak levels of creatine kinase (CK)-MB and troponin I were measured and angiographic findings were analyzed. Side branch status was also assessed. All PCIs were successful. One cerebrovascular infarction and one acute ST segment elevation myocardial infarction with acute stent thrombosis occurred in the nicorandil group. No deaths occurred, and no other major cardiac adverse events were observed in either group over 6 months follow-up. The post-PCI peak CK-MB and troponin I levels were not significantly different between the two groups. There were no significant differences between the nicorandil and control subjects in side branch occlusion or flow reduction, or in the jail index. CONCLUSIONS Intra-coronary nicorandil infusion had no significant effect on PMI and cardiac enzymes after PCI in patients with stable or unstable angina.

Successful Treatment of a Ruptured Aortic Arch Aneurysm Using a Hybrid Procedure

Aortic rupture has a high mortality rate and can be considered a medical emergency. The standard treatment for aortic rupture is surgical repair. An aortic stent graft for a ruptured descending aorta is considered an effective alternative treatment. However, an aortic stent graft is difficult when the aortic aneurysm is in the aortic arch due to supra-aortic vessels. We report on a patient with a ruptured aortic arch aneurysm treated with a hybrid procedure, which involved a carotid to carotid bypass operation and an aortic stent graft. A 71-year-old male patient visited our cardiovascular center suffering from hemoptysis. The chest CT and aortography showed a 9 cm sized aortic arch aneurysm 0.5 cm distal to the left subclavian artery and a hemothorax in the left lung. The patient refused to undergo a full open operation. We performed a carotid to carotid bypass in advance, and two pieces of aortic stent grafts were placed across the left carotid artery and left subclavian artery. The follow up CT showed the aortic stent grafts, no endoleaks and no thrombus in the aortic arch aneurysm. The patient was discharged from the hospital without complication.

ANALYSIS OF RINGING BY CONTINUOUS WAVELET TRANSFORM

This paper investigates the ringing phenomenon by using continuous wavelet transform (CWT). Experiments were conducted in a wave tank. Breaking waves were generated to understand the ringing phenomenon. The model tested was a surface piercing circular cylinder and the time series of the wave height and force on the cylinder was measured. An analysis was conducted using continuous wavelet transform. The scalograms of the time series of the wave height and those of the forces showed that high frequency components were generated at the onset of the breaking wave impact in the time domain. It was concluded that, ringing is a natural frequency response due to the breaking wave impact.