Cardiovascular radiology最新文献

A nationwide survey of complications due to coronary arteriography during 1973--74 yielded responses from 176 hospitals (89,079 coronary arteriograms). The overall mortality rate was 0.14% (brachial, 0.12%; femoral, 0.16%). In the brachial group, the mortality rate was three times as high for non-heparinized as for heparinized patients. In institutions performing fewer than 100 examinations per year, the combined incidence of death, myocardial infarction, and cerebral embolism was five times higher than in institutions performing more than 400 examinations per year. Left main coronary artery or three-vessel disease was present in most patients who died of the procedure. Compared to a previous survey of 1970--71, there was a profound decrease in significant complications (including death, myocardial infarction, and cerebral embolism) and entry site complications such as thrombosis. A reduction in mortality with the femoral technique since 1971 was not accounted for by heparinization and may reflect increasing experience with the method and shorter angiographic times.

In five instances, transverse aortic arch aneurysms were found that had initially, clinically and radiographically, mimicked thoracic neoplasms. Transverse aortic arch aneurysms display a wide spectrum of presentation: they may be asymptomatic, or they may cause symptoms secondary to esophageal, bronchial, vascular, or neural compression within the mediastinum and so mimic neoplasms. Conventional radiography in four projections and tomography are important components of the diagnostic evaluation of middle mediastinal masses. However, because plain film analysis is unable confidently to distinguish selected uncalcified aortic arch aneurysms from neoplasms, thoracic aortography is essential to the diagnosis.

In two patients with renal cell carcinoma, late metastases to the remaining kidney were found. The metastases were histologically identical to the primary tumor, and more than one nodule recurred in both cases. Advanced surgical techniques allowing removal of metastases from the sole kidney make diagnosis of these lesions clinically important.

Transhepatic obliteration of gastroesophageal varices was performed in 18 actively bleeding patients. The success of the procedure was related to the complete obliteration of the varices, as demonstrated by their disappearance at angiography. In 13 of the 14 patients in whom obliteration was complete, bleeding did not recur. Three of the 13 died of hepatic insufficiency within 18 days of embolization, and three refused surgery and were lost to follow-up. The remaining seven patients had portacaval or mesocaval shunts, and are doing well at a follow-up of 12 months. Transhepatic obliteration has, therefore, proved to be an effective emergency procedure in patients who will be acceptable surgical candidates at a later date.

Distinguishing posterior mediastinal and pulmonary masses from aneurysms and tortuosity of the descending thoracic aorta may be difficult, as five such cases illustrate. Both the neoplasms and the aortic aneurysms or tortuosity can compress the same vital mediastinal structures; thus, they may give rise to the same symptoms. Because the plain film findings may also be similar, aortography is essential to their diagnosis.

Dilatation of the ascending aorta, a frequently reported sign of aortic stenosis, was assessed in 47 patients for whom aortic angiograms has been recorded. Twenty-eight of the patients had rheumatic valvar disease and 19 had congenital aortic stenosis. A simple ratio between the maximal width of the mid-ascending aorta and the width of the aortic root was calculated. Patients with congenital aortic stenosis had significantly greater supravalvar aortic dilatation than did those with rheumatic aortic valve involvement. There was no correlation between the pressure difference across the aortic valve and degree of dilatation of the ascending aorta.

Benign and malignant smooth muscle tumors of the small intestine have each been considered as displaying distinct angiographic characteristics. However, as two cases illustrate, the angiographic features of benign and malignant smooth muscle tumors overlpa, and radiographic differentiation of these tumors is not feasible. In most cases angiography can distinguish smooth muscle tumors from other vascular lesions.

In five patients with obstruction of the inferior vena cava, collateral flow to the portal vein was demonstrated. Although there are many reports on caval occlusion, only 21 cases with this collateral circulation pattern have been reported. The reasons for this are most likely technical: To demonstrate this circulation, a large volume of contrast medium must be used and, because of the low flow velocity in the numerous wide collaterals, delayed films are also necessary.

The validity of noninvasive (iodine-131 iodohippurate renogram, iodine-131 ortho-iodohippurate clearance, indium-113m EDTA--technetium-99m DTPA sequential renal scan) and invasive (xenon-133 washout) radionuclide screening tests was evaluated in the diagnosis of 105 patients with unilateral renovascular hypertension (RVH) and in 45 patients with essential hypertension (EH). In RVH positive findings on the stenosed side were noted in 73% of renograms, 73% of o-iodohippurate-clearance tests (N = 22), 81% of sequential renal scans, and 90% of xenon-washout studies (N = 67). In a subgroup of 55 retrospectively selected patients with normal or improved blood pressure following renovascular surgery, the preoperative findings had been positive on the stenosed side in 78% of renograms, 75% of o-iodohippurate-clearance tests (n = 20), 85% of sequential renal scans, and 93% of xenon-washout studies (n = 23). The sequential renal scan appears to be a sufficiently reliable method in noninvasive screening for unilateral RVH, although invasive xenon-washout studies show a higher percentage of hemodynamic alterations in the stenosed kidney. o-iodohippurate clearance tests, and in particular xenon-washout studies, can reveal arteriosclerotic lesions in the contralateral, non-stenosed kidney, which may be of importance when the decision for renovascular surgery is pending.

A heparinized catheter was used for the regional infusion of 5-fluorouracil in seven patients with liver metastases. The hepatic artery was catheterized from the left brachial artery. The period of treatment varied from one to 13 weeks. Pull-out angiograms, obtained after eight catheterizations, revealed complete occlusion of the brachial artery in five and partial occlusion in three, although no patient had ischemic symptoms in the hand. Thus, heparinization of the catheter did not prevent thrombosis during long-term infusion therapy.