64-row multi-dector computed tomography coronary image from a center with early experience: first illustration of learning curve

Background and objectives The recent joint ACCF/AHA clinical competence statement on cardiac imaging with multi-detector computed tomography recommended a minimum of 6 months training and 300 contrast examinations, of which the candidate must be directly involved in at least 100 studies. Whether this is adequate to become proficient in interpretation of coronary computed tomography angiography (CTA) is not known. The aim of our study was to plot the 'learning curve' for CTA assessment of haemodynamically significant coronary stenosis in a center with 1 year's experience using a 64-row scanner. Methods A total of 778 patients underwent contrast-enhanced CTA between January and December 2005. Out of these patients, 301 patients also underwent contrast-enhanced conventional coronary angiography (CCA). These patients were divided into 4 groups according to the time the examination was underwent. Group Q1: first quarter of the year (n=20), Group Q2: second quarter (n=128), Group Q3: third quarter ( n=134), and Group Q4: fourth quarter ( n=19). For Group Q4 patients we used a 'test-bolus' protocol instead of 'bolus-tracking' for contrast-enhancement. Results The sensitivity, specificity, positive, and negative predictive values were Ql - 64%, 89%, 49% and 94%, respectively; Q2 -79%, 96%, 74% and 97%, respectively; Q3 - 78%, 96%, 74%, 97%, respectively, and Q4 - 100% for all. Conclusions In a center with formal training and high caseload, our accuracy in CTA analysis reached a plateau after 6 months experience. Test-bolus protocols produce better image quality and can improve accuracy. New centers embarking on CTA will need to overcome an initial 6-month learning curve depending upon the caseload during which time they should consider correlation with CCA. (J Geriatr Cardiol 2006; 3(1):29-34)     

ON HELMINTH PARASITES OF RATS IN KWEIYANG

Rats by reason of their great number constitute in the south- western part of China a serious household pest, and as possible disease carriers for man and domestic animals deserve urgent attention. The present report embodies part of a preliminary survey on the parasitic fauna of the common vertebrate in the vicinity of Kweiyang which was begun in the summer of 1938 and concerns only with the helminth parasites of rats.     

Efficacy of a 1‐week rabeprazole triple therapy for eradicating Helicobacter pylori and ulcer healing: an ‘in‐clinical‐practice’ study

OBJECTIVE: To determine the efficacy and tolerability of a 1‐week treatment regimen consisting of rabeprazole and two antibiotics, clarithromycin and amoxicillin, in the eradication of Helicobacter pylori in an ‘in‐clinical‐practice’ setting. METHODS: Patients selected had unequivocal evidence of H. pylori infection based on urease test and histology of antral and corpus biopsies obtained at endoscopy. Patients with complicated ulcers were not included. Patients received rabeprazole 10 mg b.i.d., clarithromycin 500 mg b.i.d. and amoxicillin 1 g b.i.d. for 1 week and were assessed for successful eradication at least 4 weeks after completion of therapy by repeat gastroscopy and gastric biopsies. Eradication was defined as absence of bacteria in both antral and corpus biopsies tested by histology and urease test. Ulcer patients did not receive continued acid suppression therapy following the 1‐week course of treatment. RESULTS: The study recruited 205 patients of whom 25 were not compliant with the medications or defaulted on follow‐up and were therefore not included in the per‐protocol analysis. Eradication of H. pylori was successful in 166/180 of patients on per‐protocol analysis (92.2% [95% CI: 87.3, 95.7]) and in 169/205 patients on intention‐to‐treat analysis (82.4% [95% CI: 80.5, 90.2]; P = 1.000). There were 47 patients with active ulcers: DU 27, GU 18, DU/GU 2. Overall, ulcer healing was achieved in 42 of 44 (95.5%) patients who had successful eradication of H. pylori infection, but ulcers did not heal in any of the three patients (DU 2, GU 1) who did not eradicate the infection. Of the total group, 199 were assessed for compliance and side‐effects of treatment. Side‐effects were in general mild and tolerable. Of 14 patients who were not compliant with medication, 4 (2.0%) attributed it to side‐effects of treatment (increased abdominal pain, dizziness and taste disturbances) and the remaining 10 did not give specific reasons. The most common side‐effect was bitter taste, reported by 39.2% of patients. Other side‐effects, such as giddiness, increased abdominal pain, lethargy, loose bowel motions and skin rash, were mild and found in only a small percentage of patients. CONCLUSIONS: The rabeprazole 1‐week triple therapy with amoxicillin and clarithromycin is effective in eradicating H. pylori in an ‘in‐clinical‐practice’ setting. The treatment was well tolerated by patients. Good ulcer healing was achieved with short‐course H. pylori eradication therapy without the need for continued acid suppression.     

Transesophageal Defibrillation: Animal Studies and Preliminary Clinical Observations

Ventricular fibrillation (VF) that fails to respond to transthoracic defibrillation leaves the clinician with few alternatives. The purpose of this study was to develop a technique of rescue defibrillation by use of transesophageal electrodes. Fourteen anesthetized dogs (20 30 kg) were investigated in this study. Two electrodes (300 mm²) were mounted 8 cm apart on an esophageal probe and inserted approximately 40 cm from the mouth. VF was induced using AC current delivered to the myocardium. Defibrillation was then performed between the distal electrode (anode) and anterior skin patch (cathode). After 15 seconds of induced VF, transesophageal and transthoracic defibrillation thresholds (DFTs) were determined in random order. The esophageal DFT (90 ± 15 joules) tended to be lower than the transthoracic DFT (115 ± 35 joules), though this difference was not statistically significant. One dog could not be defibrillated by transthoracic defibrillation but responded to transesophageai defibrillation. Esophageal electrodes were also useful for arrhythmia discrimination and ventricular pacing (pacing threshold of 38 ± 5 mA at a pulse duration of 2.5 msec). Following transesophageal DFT determination, in ten dogs (total energy of 600 ± 150 joules), acute esophageal histopathology demonstrated mild to severe focal injury to the mucosa and/or muscular layers. However, esophagi in four chronic dogs (total energy of 470 ± 110 joules) showed no gross evidence of macosal damage, perforation, or stricture 4 weeks following defibrillation. Histopathology showed only focal myocyte atrophy and repair. As a last resort, transesophageal defibrillation was performed in the emergency room on four patients with out-of-hospital refractory VF who failed > 6 high energy transthoracic shocks. Transesophageal defibrillation successfully terminated VF in each patient in spite of ≥ 50 minutes of cardiac arrest, however, none of the patients survived the initial resuscitation, Jn conclusion, transesophageal defibrillation is as effective as transthoracic defibrillation in a canine model and safe up to a total energy of 600 joules. Preliminary clinical trials suggest that this method results in conversion from VF when trunsthoracic defibrillation fails.     

Adult onset Mongolian spot

We report a case of adult onset, unilateral, progressive, grey-blue pigmentation on the back of an Asian male. Histology showed the pigmentation to be due to deep dermal melanocytes. The spectrum of clinical presentations of dermal melanocytosis is reviewed and the unique features of this case outlined.     

136例巨大左室瓣膜置换术后并发症危险因素分析

目的 分析巨大左室瓣膜置换术后危险因素,提高术后监护救治水平.方法 SPSS二分类Logistic回归分析本院1998年1月至2005年6月收治的136例巨大左室[左室舒张末期前后径(LVED)＞70 mm]患者的术后危险因素.结果 术后主要并发症为心律失常52例(38.2%),活动性出血26例(19.1%),心包填塞8例(5.9%),低心排出量综合征7例(5.1%),低氧血症者8例(5.9%),肺部感染3例(2.2%).术后早期病死率为6.6%,死亡原因为室颤(2.2%)、低心排(2.2%)、ARDS(0.7%)、多器官功能衰竭(1.5%).经SPSS二分类Logistic回归分析显示,术中转流时间、阻断时间、呼吸机支持时间、心肌酶谱水平是术后死亡和并发症发生的危险因素.巨大左室与术后呼吸机辅助时间(r=0.206,P＜0.05)、并发症发生(r=0.342,P＜0.01)、术后心功能(r=0.386,P＜0.01)和术后AST变化(r=0.304,P＜0.05)呈显栽著正相关.结论 巨大左室瓣膜置换术后各种并发症发生率高,患者术中转流阻断时间长、心肌保护不良、长时间呼吸机辅助呼吸等因素可能是术后患者死亡和并发症发生的危险因素.