Internal mammary artery graft fistulae to the pulmonary arteries as a cause of myocardial ischaemia after coronary artery bypass Graft.

Internal mammary artery (IMA) graft fistula to the pulmonary arteries is a cause of myocardial ischaemia after coronary artery bypass grafting (CABG). Surgical and percutaneous interventional treatments are available, both with their inherent risk and benefits. Optimised medical management is therefore essential. A pre CABG IMA angiographic image may assist surgeons to ligate identifiable accessory branches, which may contribute to fistula formation.

Thermodilution left-sided cardiac output for valve area determination after balloon mitral valvotomy.

This study was conducted to establish the validity of left-sided cardiac output measurement with a Swan-Ganz catheter and assess its accuracy in estimating mitral valve area (MVA) by the Gorlin formula. The use of right-sided cardiac output after balloon mitral valvotomy (BMV) can give inaccurate measurements for Gorlin-derived MVA because of the atrial septal defect (ASD) created during the procedure. The left-sided cardiac output was measured with a Swan-Ganz catheter (proximal port in the left atrium and then in the left ventricle, and distal port in the ascending aorta) in 10 consecutive patients before and after BMV. Gorlin-derived MVA cardiac output by this method was compared with (1) Gorlin-derived MVA by means of right-sided cardiac output with and without balloon occlusion of the ASD and (2) MVA measured by echocardiography. Before BMV, a close agreement with a good correlation between left-sided and right-sided cardiac output was found (r = 0.83, p = 0.006). Furthermore, Gorlin-derived MVA by cardiac output with either method was comparable with valve area by echo. After BMV, left-sided cardiac output correlated well (r = 0.92, p = 0.0002) and was comparable with right-sided cardiac output with occlusion of the ASD (mean difference 0.17 +/- 0.49 L/min, p = 0.3) but was significantly lower than the value obtained with open ASD (mean difference 0.93 +/- 0.77 L/min, p = 0.004). Comparison of the correspondent MVAs yielded similar results. Gorlin-derived MVA with left-sided cardiac output and MVA by echo were also similar.(ABSTRACT TRUNCATED AT 250 WORDS)

Sequential directional atherectomy of coronary bifurcation lesions.

Conventional techniques of coronary angioplasty for lesions at coronary bifurcations are well documented, are sometimes cumbersome, and have inherent limitations. We describe a technique for sequential atherectomy at coronary bifurcations. Further evaluation is needed to determine the overall safety, efficacy, applicability and durability of sequential directional atherectomy at coronary bifurcations.

Transseptal catheterization update 1992.

Resurgence of the transseptal procedure in the last decade has occurred coincident with the advent of therapeutic catheterizations and in particular mitral balloon vavuloplasty. As larger numbers of these procedures have been performed, experience shows that the position of intended septal puncture varies for each anticipated procedure and need not lie at the fossa ovalis, which is frequently displaced or inaccessible. Recognizing the dynamic alterations in septal and atrial anatomy that accompany the various combinations of valvular heart disease, the experienced interventionalist will use precatheterization echo and radiological techniques to enable precise and localized transseptal puncture. Using these techniques in 597 patients for valvular heart disease, we have had no deaths and a morbidity of 1.8% with the transseptal puncture.

Balloon expandable stents to treat central venous stenoses in hemodialysis patients.

Vascular access failure in hemodialysis patients remains a significant problem. The use of thrombolytic agents and balloon angioplasty instead of or in conjunction with surgical revision, has been helpful in increasing the life span of vascular access in these patients. The application of newer endovascular therapies, such as vascular stents, may further improve the salvage rate of hemodialysis access sites. These stents may be particularly valuable in treating stenoses in large central veins. We present 2 cases in which a balloon-expandable Palmaz stent was used to treat a central venous stenosis causing signs of vascular access failure.

Flow support catheter for prolonged maintenance of coronary blood flow.

A newly designed flow support catheter with a supporting wire mesh cage which can be expanded into a tubular configuration and then readily reduced was evaluated in mongrel dogs. Regional myocardial blood flow (RMBF) was measured using the radioactive microsphere technique in the area of both balloon-denuded instrumented and control non-instrumented coronary arteries following placement of either a fixed-wire or a higher profile rapid exchange flow support catheter. At 5, 20, and 180 min following delivery and expansion of either device, RMBF was not significantly different in left ventricular subepicardium and subendocardium perfused by the instrumented vs. the control coronary arteries. Angiography demonstrated widely patent instrumented arteries in 15/18 dogs; in no dog was side branch occlusion observed. Significant cage thrombus deposition was seen angiographically in 3 animals causing temporary total coronary occlusion in 1. Following reduction and removal of the flow support catheter, vessel patency was present in all dogs. The flow support catheter is an effective endovascular stenting device capable of providing structural arterial support, while simultaneously maintaining distal coronary blood flow. It is envisioned that the primary application of this catheter will be to enable primary salvage of vessels acutely injured during coronary angioplasty, by "tacking up" intimal flaps for an extended period. It may also provide a bridge to emergency surgical revascularization.

Dual-chamber pacing in the cardiomyopathy of primary amyloidosis.

Cardiac function in a 75-year-old woman with primary amyloidosis and a restrictive cardiomyopathy deteriorated markedly after the occurrence of high-grade atrioventricular block. Atrial synchronous cardiac pacing, which was unreported previously in this setting, produced a marked improvement in cardiac performance.

Intracerebral haematoma mimicking intracranial neoplasm at computed tomography.

The diagnosis of a typical acute intracerebral haematoma is comparatively specific with computed tomography. Three cases are presented to illustrate computed tomographic similarities between intracerebral haematomas and intracranial neoplasms. In the appropriate clinical setting, an incorrect diagnosis may be reached unless these similarities are borne in mind.

Experimental edema disease of swine (E. coli enterotoxemia). I. Dectection and preparation of an active principle.

Freeze-thaw lysates prepared from strains of Escherichia coli belonging to serogroups O138, O139, and O141 contained a principle (edema disease principle) which induced edema disease in swine. All freeze-thaw lysates contained endotoxic activity that tended to obscure the edema disease syndrome and methods were developed to reduce such activity. Freeze-thaw lysates prepared from E. coli O139 induced the most characteristic edema disease syndrome. Partially purified edema disease principle prepared from O139 freeze-thaw lysates by sequential precipitation with ammonium sulphate and streptomycin sulphate had increased specific activity with markedly reduced endotoxic activity. This material was insoluble at acidic pH but readily soluble at alkaline pH. The effective molecular weight of edema disease principle, based on retention and filtration properties of diaflo membranes, appeared to be greater than 50,000 and less than 100,000. The biological activity of edema disease principle was thermolabile. Sodium deoxycholate treatment of edema disease principle further reduced endotoxic activity. A thermolabile, ammonium sulphate precipitable material was prepared from E. coli O139 that induced a predictable syndrome which resembled edema disease clinically and pathologically following intravenous inoculation in pigs.

Experimental edema disease of swine (E. coli enterotoxemia). II. The development of hypertension after the intravenous administration of edema disease principle.

The intravenous inoculation of edema disease principle induced profound hypertension in pigs. The increase in blood pressure occurred approximately 40 hours after inoculation and coincided with the development of the characteristic neurological disturbance of edema disease. Therefore hypertension may play a pathogenetic role in the neuropathy of experimental edema disease.

Experimental edema disease of swine (E. coli enterotoxemia). 3. Pathology and pathogenesis.

Experimental colibacillary (Escherichia coli) enterotoxemia as described in this report mimics natural edema disease both clinically and in gross pathology. The histopathology is characterized by accumulations of non-inflammatory edema and by arteriopathy. The smaller arterial and arteriolar changes recorded here are similar to those described in natural edema disease. The vascular changes described in recovered cases of experimental colibacillary enterotoxemia concur with those reported in so-called subacute and chronic edema disease. The arteriolar changes that occur in colibacillary enterotoxemia of swine are comparable to those associated with hypertension. Thin sections of cerebral cortex from four pigs with acute experimental edema disease were examined by electron microscopy in an attempt to demonstrate brain edema. Sections from one pig taken during the convulsive phase of disease revealed dilatation of perivascular glial processes. However, examination of sections taken from three other pigs during an earlier phase of the neurological disturbance revealed no significant lesions. We were unable to ascertain the role of brain edema in the pathogenesis of the nervous system disturbance in these experiments.