Coronary Artery Fistulas in Adults Clinical and Coronary Angiographic Aspects.

Contains fulltext : 30188_coroarfii.pdf (publisher's version ) (Open Access)RU Radboud Universiteit Nijmegen, 25 september 2007Promotor : Werf, T. van der175 p

Ventriculo-venous communications in adults: ventriculographic observations in two female patients

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Generation of representative weather--Year data for Saudi Arabia

In recent years, the computation of load and energy requirement in buildings, energy conservation studies in buildings, and the design of solar systems are not accomplished using long-term averages of weather data as inputs, but preferably with data-sets representative of the climatological features of the site that are generated for this purpose. Such data-sets are the test reference year, typical meteorological year and weather year for energy calculations. In this paper, the basis, the selection procedure and the use of each of these data-sets are discussed. Also, an attempt is made to generate typical weather years for the cities of Dhahran, Riyadh, Jeddah, Khamis-Mushayt and Hail, using the standard meteorological data obtained by measurements by the Meteorology and Environmental Protection Administration.

Dutch survey of coronary artery fistulas in adults: congenital solitary fistulas.

AIMS: Congenital coronary artery fistulas are frequently identified in adult and pediatric populations and they have been associated with various clinical and morphological features. The purpose of this study was to define the clinical and coronary angiographic morphological characteristics of adult patients with congenital solitary CAFs in the Dutch Registry. METHODS AND RESULTS: Fifty-one patients with angiographically documented CAFs were reviewed for clinical evaluation, used non-invasive and invasive diagnostic tools and treatment modalities. Unilateral CAFs were predominant (80%) and 84% of the patients were symptomatic. The most common presenting symptom was angina pectoris (57%). Angina pectoris was present in a quarter of the patients in the absence of coronary artery disease (CAD). Significant CAD was present in 49% of the patients. Twenty-nine percent of the CAFs showed aneurysmal formation, underlying their potential hazard of rupture. Myocardial infarction occurred in 18% of the patients. In 27% of CAFs multiplicity of the origin was found and nearly all fistulas were tortuous (97%). Treatment modalities were conservative medical in 70%, percutaneous transluminal embolisation in 5% and surgical ligation in 25% of the cases. Multiple micro-fistulas from the coronary arteries to the left ventricle were excluded from the study. CONCLUSION: In this national survey series, congenital solitary CAFs can be presented with typical angina pectoris in the absence of obstructive CAD. Fistula-related coronary artery was infrequently involved in the development of ipsilateral myocardial infarction. Tortuousity and multiplicity of the CAFs may determine, for the individual patient, the choice of the currently available treatment modalities

Dutch survey of congenital coronary artery fistulas in adults: coronary artery-left ventricular multiple micro-fistulas multi-center observational survey in the Netherlands.

Item does not contain fulltextBACKGROUND: Congenital coronary artery-left ventricular multiple micro-fistulas (CA-LVMMFs) in adults are rare anomalies. They may cause angina pectoris and myocardial infarction in association with normal coronary arteries. METHODS AND RESULTS: From the medical databases of a Dutch Survey of coronary artery fistulas in adult cardiology population (30,829 patients), we identified 20 patients with CA-LVMMFs out of 71 fistula-subjects between 1996 and 2003. Clinical files and individual coronary angiograms were reviewed and analysed. There were 13 females and 7 males with a mean age of 67.3 years (range 49-82). The main presenting symptoms were angina pectoris and dyspnea in 70% of the patients. The ECG showed pathologic changes in 75%. Exercise tolerance test and 201-thallium stress scintigraphy were positive for myocardial ischemia in 29% and 50%, respectively of the tested patients. In the absence of significant atherosclerotic coronary artery disease, ipsilateral to the fistulas, myocardial infarction was documented in 15% of the patients. Chest X-ray revealed cardiomegaly in 38% of the patients. Congestive heart failure was documented in 10% of the patients. Uni-, bi- and multilateral fistulas were present in 50%, 45% and 5%, respectively. The origin was the LCA in 71% and the RCA in 29% of the fistulas. The majority (97%) originated from the mid or distal segments of the coronary vessels. Among those patients, the coronary arterial tree had single, dual, and triple vessel disease in 25%, 15% and 5%, respectively. Angiographic anatomy precludes surgical intervention; they were all followed by conservative medical management. CONCLUSIONS: Coronary artery-left ventricular multiple micro-fistulas are found more often in female patients. Furthermore, they originated from the distal segment of the coronary arteries. Coronary artery-left ventricular multiple micro-fistulas, in the presence of normal coronary arterial tree, may often lead to angina pectoris and coronary insufficiency

HCFC 22 as a replacement for CFC 12

This paper discusses the theoretical differences in performance between using R-12 and R-22 resulting from changes in thermodynamic properties. It also assesses the potential for using R-22 as a replacement for R-12 by considering a case study of an R-12 reciprocating air-conditioning unit conversion to an R-22 unit.