BACKGROUND AND METHOD: For decades, the presence of aortic insufficiency (AI) has been considered a potential hazard in military aviation and has generally excluded aircrew from high performance flight. The cardiovascular effect of repeated exposure of high +Gz forces associated with AI is largely unknown. To evaluate whether the flying of High Performance Aircraft (HPA) was detrimental to subjects with AI, we performed a retrospective review. we studied 32 asymptomatic patients in whom 16 of them had flying time with AI in HPA(Group I), others(GroupII, Control Gr.) in Low-G Aircraft(LGA). Among them, the data of 24 patients were available, 12 in group I., and 12 in group II. The two groups were matched for age, severity of AI, and flying time. RESULTS: Interval echocardiographic, and cineangiographic studies were obtained over a mean period of 4.6+/-2.6 years in group I and 5.9+/-4.2 years in group II (range, 0.9 to 12.7 years) and mean flying time with AI of 528.1+/-435.0 hours in group I and 865.0+/-816.1 hours in group II (range, 50 to 2290 hours). By paired-t test, there were no significant differences between both groups in left ventricular end-diastolic dimension (LVEDD), end-systolic dimension (LVESD), aortic dimension (Ao.D) and fractional shortening (FS) by echocardiography (p>0.05) and by multiple linear regression, there were no significant interval changes of above values in Gr. I according to increasing of flying time with AI (p>0.05). Visual grade by doppler echocardiography or aortic cineangiography increased 1 patient in Gr.I and 2 patients in Gr.II within no more than one grade. CONCLUSION: Thus, this study demonstrated that : 1) Quantitative echocardiographic measurements such as LEVDD, LVESD, Ao.D and FS didn't show significant interval change in Gr.I.2) A single subject with a minor increase in AI severity together with no difference between the HPA and LPA groups argue for a relatively chronic effect of high G exposure in aircrew with mild AI.
Aircraft ; Aviation ; Cineangiography ; Diptera* ; Echocardiography* ; Echocardiography, Doppler ; Humans ; Linear Models ; Military Personnel ; Retrospective Studies

No abstract available.

BACKGROUND: There are many evidences that inflammation is an important determinant of the development of atherosclerosis and one of the systemic markers of inflammation, C-reactive protein(CRP), is associated with extent of coronary artery disease and risk of coronary events. We assessed the time response of CRP response after coronary angioplasty and it's influence on the clinical restenosis in angina patients. MATERIALS AND METHODS: Patients included 36 angina patients undergoing single vessel angioplasty. Levels of CRP were measured before and 12, 24, 48, and 72 hours after angioplasty. Clinical restenosis was assessed at 6 months after procedure. RESULTS: Baseline CRP level was 0.30+/-0.01 mg/dL in stable and 0.46+/-0.28 mg/dL in unstable angina patients(p<0.05). After angioplasty, CRP level was increased with peak at 24 hour and persisted to 72 hours after angioplasty. At 24 hour after angioplasty, the magnitude of CRP change was 0.32+/-0.31 mg/dL in stable and 0.79+/-0.73 mg/dL in unstable angina patient(p<0.05). The change of CRP level was not associated with troponin-T after angioplasty. In unstable angina patients, clinical restenosis was developed in 8% of patients with low baseline CRP levels and in 50% of those with high baseline CRP levels more than 0.6 mg/dL(p<0.05). CONCLUSION: In unstable angina patients, inflammatory response is more increased than stable angina patients, and increased inflammatory response effects on the restenosis after coronary angioplasty.
Angina, Stable ; Angina, Unstable ; Angioplasty* ; Atherosclerosis ; C-Reactive Protein* ; Coronary Artery Disease ; Humans ; Inflammation ; Troponin T

The 8 cases of left ventricular thrombus detected by the 2 D echocardiography or left ventriculography, after acute transmural anterior myocardial infarction were effectively lysed by the thrombolytic agents and heparin therapy. The thrombolytic agents were either urokinase or tissue plasminogen activator. Urokinase was infused intravenously at a dose of 1.0 million unit for three days. And tissue plasminogen activator was infused at a dose of 100mg for a day. In all cases, the thrombi were completely lysed. At follow up, no recurrence of left ventricular thrombus was found. We have experienced 2 cases of peripheral embolization in which, left ventricular thrombi were protruding nonmobile type. The one was the embolic cerebral infarction, the other was transient hoarseness and paresthesia on the left foot, which may be transient ischemic attack. These results show that left ventricular thrombi can be treated by intravenous thrombolytic agents without life-threatening complication. However, for the better establishment of the risk and benefit of therapy further investigation is needed.
Cerebral Infarction ; Echocardiography ; Fibrinolytic Agents ; Follow-Up Studies ; Foot ; Heparin ; Hoarseness ; Ischemic Attack, Transient ; Myocardial Infarction* ; Paresthesia ; Recurrence ; Thrombolytic Therapy* ; Thrombosis* ; Tissue Plasminogen Activator ; Urokinase-Type Plasminogen Activator

BACKGROUND AND OBJECTIVES: Percutaneuous transvenous mitral commissurotomy(PTMC) has been performed as an effective non-surgical treatment modality of rheumatic mitral stenosis. Mitral regurgitation(MR) as a complication of the procedure occur in 20-53% of the patients. The moderate to severe mitral reguargitation, created by the PTMC, sometimes leads to the requirement for mitral valve replacement, but most of the MR limits the optimal dilation of mitral commissure due to the worry about the progression of the MR. This study was designed to evaluate the occurrence of mitral regurgitation and predictive factors for the moderate to severe mitral regurgitation(grade> or =2) induced by PTMC. METHODS: This study enrolled 46 patients(female 42, mean age 45 years) who have performed PTMC in Yeungnam University Hospital from May 1996 to May 1999. We analyzed the occurrence rate of mitral regurgitation(MR) and predictive factors for MR grade> or =2 after procedure. RESULTS: MR was detected in 35% of the patients prior PTMC, and in 56% after the procedure(grade 1, 30%; grade 2, 15%; grade 3, 11%). 21 cases of the MR was commissure MR as a grade< or =2. MR grade 3, occured in 5 patients, was non-commissure MR caused by the unilateral rupture of the lateral commissure in 4 patients and tearing of the annulus in one patient. On the univariate analysis, patients with MR grade> or =2 showed more frequent atrial fibrillation, mitral regurgitation and fluoroscopic calcification, and had more severe symptoms than patients with MR grade<2 before the procedure. On the analysis of the calcification, there was no significant difference of the leaflet calcification score, but the commissure calcification score was significantly higher in MR> or =2 group than MR<2 group(1.5+/-0.54 vs 2.5+/-0.96, p=.02). On the multivariate logistic regression analysis, independent predictor of MR grade> or =2 was fluoroscopic mitral calcification(OR 6.38, p=.048). CONCLUSION: Mild to moderate commissure MR was observed in most of the patients after PTMC. Commissure calcification have more influence on the development of MR grade> or =2 than valvular calcification, and the fluoroscopic mitral calcification can predict the occurrence of MR grade> or =2 mitral regurgitation after PTMC.
Atrial Fibrillation ; Humans ; Logistic Models ; Mitral Valve ; Mitral Valve Insufficiency* ; Mitral Valve Stenosis ; Rupture

BACKGROUND: It is well known that ischemic preconditioning protects the heart against infarction or arrhythmias from a subsequent ischemic injury. Recent laboratory data indicate that the adenosine during the ischemic period may trigger protection via A1 or A3 adenosine receptor and also protein kinase C(PKC) plays a central role. This study was designed to determine the role of adenosine receptor subtypes and PKC in the preconditioning protection. METHODS: All cat heart groups were subjected to 40min ischemia and 30min reperfusion. The preconditioning protocol consists of 4min ischemia and then 10min of reperfusion 4 times. The effects of ischemic preconditioning, nonselective adenosine receptor blocker(SPT), an A1 specific antagonist(DPCPX) and protein kinase C inhibitor(Polymyxin B), on ischemic preconditioning were determined by infarction size. There were 5 groups : (1) control group (Group 1, n=10)(2) Ischemic preconditioned group(Group 2, n=9)(3) DPCPX pretreatment group(Group 3, n=6)(4) SPT preteatment group(Group 3, n=6)(5) Polymyxin B pretreatment group(Group 5, n=6). SPT and DPCPX were given intravenously 5 min before ischemic preconditioning. Polymyxin B was administered to cats for 30min during ischemic preconditioning period. RESULTS: Ischemic preconditioning only or pretreatment with DPCPX prior to preconditioning demonstrated a significant reduction in infarct size(22.6+/-1.5, 25.4+/-0.9% infarction of the risk zone, respectively, p<0.05) with respect to control, SPT-pretreatment, and polymyxin B-pretreatment groups(44.0+/-1.7, 43.0+/-2.0 and 40.3+/-0.4% infarction of the risk zone, respectively). CONCLUSIONS: Ischemic preconditioning protects heart from subsequent ischemia. Protection was blocked by SPT and protein kinase C inhibitor(polymyxin B), but not by A1 antagonist DPCPX. The cardioprotective effects by ischemic preconditioning in the in vivo cat heart appear to be dependent on A3 adenosine receptors and activation of protein kinase C.
Adenosine* ; Animals ; Arrhythmias, Cardiac ; Cats* ; Heart* ; Infarction ; Ischemia ; Ischemic Preconditioning* ; Polymyxin B ; Polymyxins ; Protein Kinase C* ; Protein Kinases* ; Receptors, Purinergic P1* ; Reperfusion

BACKGROUND: It is well known that ischemic preconditioning protects the heart against infarction or arrhythmias from a subsequent ischemic injury. Two phases of the effect of preconditioning has been explored, early protection and second window of protection at 24 hours. The late protection was seen in some animal model, but the precise mechanism is controversal. This study was designed to evaluate the late cardioprotective effect and role of HSP70 in ischemic preconditioning of cat heart. METHODS: Two groups of cats were studied. Control animals were subjected to an episode of 40-min coronary artery occlusion followed by 30-min reperfusion. Experimental animals were subjected to ischemic preconditioning before the 40-min ishcemia/reperfusion. The preconditioning protocol was comprised of three 5-min episodes of ischemia interspersed by 10-min episodes of reperfusion. After sustained ischemia and reperfusion, left ventricular risk area and infart area were measured by injection of Evans blue bye and triphenyltetrazolium staining, and myocardial HSP70 mRNA was examined in risk(left ventricular anterior wall) and nonrisk(left ventricular posterior wall) area using northern blot hybridization. HSP70 mRNA expression was quantified as a percent of GAPDH. The late cardioprotective effects of ischemic preconditioning were determined by infarct size (% area at risk). RESULTS: Infarct size was markedly limited by ischemic preconditioning when compared with the control group (18.5+/-6.9% vs 38.5+/-11.1%; p<0.001). HSP70 mRNA expression in risk area was much higher in preconditioning group than control group(78+/-12% vs 41+/-11%; p<0.01). But, there was no significant difference of HSP70 mRNA expression in the posterior wall between control and ischemic preconditioning group. CONCLUSIONS: These data suggest that ischemic preconditioning have delayed myocardial protective effect from ischemia. The increase in myocardial HSP70 mRNA may be one of the contributing factors to the delayed cardioprotective effects of ischemic preconditioning in cats.
Animals ; Arrhythmias, Cardiac ; Blotting, Northern ; Cats* ; Coronary Vessels ; Evans Blue ; Heart* ; Heat-Shock Proteins* ; Hot Temperature* ; HSP70 Heat-Shock Proteins ; Infarction ; Ischemia ; Ischemic Preconditioning* ; Models, Animal ; Reperfusion ; RNA, Messenger

No abstract available.
Allopurinol* ; Animals ; Liver* ; Rats* ; Reperfusion Injury* ; Verapamil*

No abstract available.

One of the patellar function is to protect the femoral condyle from direct blowing to knee, so it is known that ligament injuries of the knee are rare in the presence of patellar fracture. We experienced four cases of posterior cruciate ligament injury associated with patellar fracture. Unfortunately, three cases were initially neglected, and one case was identified by visualization on avulsed posterior tibial spine in plain X-ray film. We reviewed these cases and obtained several results as follows; 1. Among four cases, three cases(75%) are fractured at the lower pole of patella without displacement and one case is a longitudinal fracture. 2. We consider possible two mechanisms of this injury; first, in flexed knee, posteriorly directed force on the proximal tibia produces posterior cruciate ligament injury followed by avulsed fracture at the lower pole of patella. Second, by fall on a flexed knee, the load is sustained on the inferior pole of the patella first and continuously drives the tibia backwards producing posterior cruciate ligament injury. We recommend that all surgeon should be aware of possibility of the ligament injury in the presence of patellar fracture, especially in lower pole fracture.
Knee ; Ligaments ; Patella ; Posterior Cruciate Ligament ; Spine ; Tibia ; X-Ray Film