The clinical significance of the differernce in left ventricular ejection fraction between rest and stress on gated myocardial perfusion SPECT / 대한내과학회지

BACKGROUND: Gated myocardial perfusion SPECT improved diagnostic accuracy of coronary artery disease and enabled us to observe motion and thickening of myocardial walls, ejection fraction as well as myocardial perfusion. Many studies suggested that there was a decrease of left ventricular ejection fraction (LVEF) at post-stress compared with that at rest gated myocardial perfusion SPECT (stunning). The objective of this retrospective study is to evaluate the clinical significance of the decrease of LVEF at post-stress gated myocardial perfusion SPECT by correlating with coronary angiographic finding. METHODS: Authors selected 41 patients who underwent exercise electrocardiography and gated myocardial perfusion SPECT between May, 2001 and May, 2002. The patients underwent coronary angiography within 6 months. The patients were divided into two groups, 16 patients in whom post-stress LVEF was >or=5% lower than rest (stunning group) and 25 patients in whom LVEF was not >or=5% lower than rest (non-stunning group). RESULTS: The number of patients with hyperlipidemia was higher in stunning group than in non-stunning group (50% vs 4%, p=0.001). The number of patients with angiographic stenoses >90% was significantly higher in stunning group than in non-stunning group (75% vs 28%, p=0.04). The number of patients with multi-vessel disease was also significantly higher in stunning group than in non-stunning group (75% vs 36%, p=0.015). CONCLUSION: The patients who had a decreased LVEF after stress (stunning) showed more severe coronary artery stenosis. This finding suggests that stunning may be an important additional indicator of underlying myocardial ischemia.

The Clinical Significance of Redefinition of Acute Myocardial Infarction by ESC/ACC

BACKGROUND AND OBJECTIVES: Epidemiologic studies and clinical trials require a more precise definition of acute myocardial infarction (AMI). The advent of sensitive and specific serologic biomarkers can identify those patients with small areas of myocardial necrosis. Acute myocardial infarction was redefined and approved by the ESC/ACC on September, 2000. To investigate the clinical implications of the revised criteria, the clinical features, the in-hospital outcomes and the 18 months outcomes were compared between the AMI patients who were diagnosed using the definition of the WHO criteria and those AMI patients added by the revised criteria. SUBJECTS AND METHODS: One hundred and seventy four consecutive patients diagnosed as AMI by the new criteria were included in the study. These patients with positive cardiac enzymes and ischemic symptoms or signs (n=174) were divided into two groups. The patients of group 1 (n=105) were the patients who were diagnosed with AMI by the WHO criteria, and the patients of group 2 (n=69), were the additional patients who were diagnosed with AMI only by the new criteria. RESULTS: The new criteria of AMI by ESC/ACC increased the numbers of AMI by 66%. As compared with group 1, women and patients with hypertension and a past history of ischemic heart disease were more common in group 2 (p<0.05). Percutaneous coronary intervention (PCI) was used less frequently and Angiotensin converting enzyme inhibitors (ACEIs), beta blockers and aspirin were prescribed less frequently in group 2. The total cardiac events and cumulative survival rate in group 1 were higher than in Group 2 (12.3% vs 7.2%, 89% vs 94%, respectively) but these differences were not statistically significant. CONCLUSION: The new criteria results in a substantial increase in the diagnosis of AMI, and the new criteria helps identify patients who were missed by the old criteria. The patients with AMI who were added by the new criteria had a similar risk of adverse outcome.

A Case of Left Main Coronary Stenting for Acute Myocardial Infarction Complicated by Ascending Aortic Dissection

We report here on a case of ascending aortic dissection combined with anterior myocardial infarction that was caused by a retrograde dissection into the left main coronary trunk and proximal left anterior descending artery. We successfully treated this with stenting of the left main coronary artery and proximal left anterior descending artery, and this allowed for the definitive surgical correction. Stenting a collapsed left main coronary artery can be lifesaving procedure and serve as a bridge to surgery.

Prevalence rate and triggering factors of syncope in medical students / 대한내과학회지

BACKGROUND: Syncope is a sudden and brief loss of consciousness associated with a loss of postural tone, from which recovery is spontaneous. The most frequently identified causes of syncope are neurocardiogenic, cardiac, cerebrovascular and side effects of drugs. However, in many cases, it is not easy to make a diagnosis of syncope. The prevalence rate of syncope also is variable according to the nature of the study. We investigated the prevalence rate, characteristics and triggering factors of syncope in young medical students. METHODS: We contacted 400 medical students of Kyungpook National University, Daegu, Korea, and a questionnaire on the prevalence, triggering factors, and recurrence rate of syncope was handed out. The data from 379 medical student (male 168, female 211, mean age 22.3 years) were included for further analysis. RESULTS: Fifty-eight students (15.3%) experienced syncope and female students reported higher prevalence rate than male students (20.4 versus 8.9%, p=0.002). Among 58 students with syncopal history, 22 students (male 2, female 20) experienced recurrent syncope. The students who experienced recurrent syncope were younger at first syncope than those without recurrent syncope (15.0 versus 17.3 years, p=0.039). The triggering factors of syncope were prolonged standing, warm environment, immediate standing, tiredness, emotional upset, menstruation, and so on. CONCLUSION: The prevalence rate of syncope was 15% in medical student with mean age of 22.3 years. As the syncope in female and early onset syncope showed higher rate of recurrence, more attention may prevent recurrent syncope in these cases.