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Biomedical subjects

D G Knauf

Publications and source records attributed to D G Knauf.

30 records · Page 2Linked to original sources
PubMed1983

Comparison of early and long-term results with intraoperative transluminal balloon catheter dilatation and coronary artery bypass grafting.

Twenty-six patients with chronic stable angina underwent intraoperative coronary artery balloon catheter dilatation and concomitant coronary artery bypass grafting (CABG). In one patient (3.8%) the catheter could not be passed through the arterial narrowing, and in two patients (8%) early angiographic evidence for arterial damage was detected. Postoperative angiographic data were available in 85% of patients early (mean 10 days) and in 50% of patients late (mean 12 months). Early results showed one perioperative myocardial infarction, 100% relief of angina, and no operative mortality. Compared to preoperative studies, of 23 angiographically visualized distal narrowings dilated in an antegrade fashion, 12 (52%) were unchanged, two (9%) were worse, and nine (39%) were improved. Those arterial segments with discrete distal narrowings (n = 13) had better angiographic results than those with diffuse distal narrowings (n = 9). In 49% of the former and in 22% of the latter arterial narrowings, improvement (increased luminal diameter) was documented postoperatively. In addition, there were four proximal narrowings which were dilated in a retrograde fashion; three were unchanged and one was improved compared to preoperative studies. Only one of 27 dilated segments (3%) was totally occluded postoperatively. Late results showed two patients (8%) developed recurrent chest pain and one patient (4%) died related to congestive heart failure. The two patients who had angiographically documented coronary arterial intimal injury showed evidence of resolution at late study. In 13 distal narrowings, six (46%) were unchanged, three (23%) were worse, and four (31%) were improved compared to the preoperative appearance. In 10 distal narrowings visualized both early and late postoperatively, nine were unchanged and one was worse. In summary, coronary artery balloon catheter dilatation during CABG is relatively safe and is associated with acceptable clinical results. Angiographic evidence for improvement is less than symptomatic relief postoperatively. Therefore, objective evaluation may be necessary for accurate determination of operative results. The need for a national registry related to intraoperative angioplasty is probably warranted.

Angina Pectoris↗
PubMed1982

Preliminary experience with intraoperative transluminal balloon-catheter dilation and coronary artery bypass grafting for the treatment of symptomatic diffuse coronary artery disease.

Transluminal balloon-catheter dilation of coronary artery lesions has become increasingly common in the cardiac catheterization laboratory. We describe a method of intraoperative dilation that may improve surgical results when used in combination with coronary artery bypass graft (CABG) operations in patients with diffusely diseased coronary arteries. In 16 patients, long-segment intraoperative dilations were performed to enlarge luminal narrowings in 21 different regions. All of these patients had postoperative coronary angiography and left ventriculography so that we could objectively evaluate the coronary dilatations. There were no operative deaths or perioperative myocardial infarctions, and angina was relieved in all patients. Of the 21 dilated segments, 12 (57%) were unchanged, 2 (10%) became worse, and 7 (33%) were improved postoperatively. In addition, two new areas of intimal damage were detected in patients with unchanged postoperative liminal diameters. We conclude that further experience and longer follow-up are necessary before the efficacy of intraoperative coronary artery balloon-catheter dilation can be accurately determined.

Angioplasty, Balloon↗
PubMed1979

Diverticula in association with the proximal left subclavian artery: a cause of mediastinal mass lesions.

The case reports of 5 patients with an aortic arch diverticulum associated with the proximal left subclavian artery are presented. In 3 patients, the left subclavian artery arose from a diverticulum off a right aortic arch and traversed the retroesophageal area to the opposite arm. In 1 patient, the left subclavian artery arose from a diverticulum off a left aortic arch; this represents the second instance of this anomaly to be reported in the literature. In 1 patient, the left subclavian artery was not attached to the aorta, and a diverticulum was present in the expected area of attachment. Confusion of these anomalies with solid mediastinal mass lesions and with aortic aneurysms may occur. Treatment is predicted on symptomatology, and resection is usually not indicated. It is necessary to remain cognizant of aortic diverticula and to differentiate them from other mediastinal mass lesions.

Adult↗
PubMed1977

Anomalous origin of left coronary artery from pulmonary artery. Case report and review of literature concerning teen-agers and adults.

An adult with angina was found to have anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA). Review of the literature regarding this anomaly in teen-agers and adults disclosed only 25 cases diagnosed during life. Eighteen additional cases of ALCAPA in this age group have been diagnosed post mortem. In this report, we will review the management of teen-agers and adults in whom ALCAPA was correctly diagnosed during life. We shall also describe the eighth case of successful aorta-left coronary artery grafting with the saphenous vein in this age group. This case brings the total in the literature to 44. Of those patients offered surgical therapy, 13 underwent successful ligation of the anomalous artery. Saphenous vein grafts were employed in 8. Five did not undergo ligation or saphenous vein grafting. There was one death. It would appear that saphenous vein grafting is the definitive means of surgically correcting ALCAPA, because it restores the dual coronary circulation.

Adolescent↗
PubMedDate not supplied

Interatrial groove tear: an unusual complication of balloon atrial septostomy.

The authors present an unusual complication of the balloon atrial septostomy procedure performed in a neonate with D-transposition of the great arteries. Cardiac tamponade developed shortly after the balloon atrial septostomy procedure and the infant was found to have a tear in the superior aspect of the left atrium, parallel to the interatrial groove. The tear was successfully sutured and may have been caused by the greater pull-back force needed if the catheter balloon is maximally distended for the first pull-back.

Cardiac Catheterization↗
PubMedDate not supplied

Acute vascular rejection of the coronary arteries in human heart transplantation: pathology and correlations with immunosuppression and cytomegalovirus infection.

Prior studies of vascular rejection in transplanted human hearts have stressed the importance of accelerated coronary arteriosclerosis (chronic vascular rejection). We, however, have had four patients with sudden onset of acute heart failure within 90 days of transplantation who have died without significant myocardial interstitial rejection or the concentric intimal thickening with dense collagen that is typical of chronic vascular rejection. In contrast, the coronary arteries in our patients had a prominent lymphocytic infiltrate, a loosely organized intimal thickening composed of smooth muscle cells, and extensive endothelial injury. We believe that these changes define acute vascular rejection of the coronary artery. In 14 transplanted hearts obtained consecutively, at autopsy or at a second transplant procedure, graft failure was caused by acute coronary vascular rejection in six cases and by chronic coronary vascular rejection in one case. The remaining seven patients showed no evidence of vascular rejection and died primarily of sepsis. Cytomegalovirus (CMV) disease was present in 6 of 7 patients with vascular rejection, of which 43% were CMV-negative recipients of hearts from CMV-positive donors. The adoption of a triple-drug protocol, in which azathioprine was added to cyclosporine and prednisone, reduced the incidence of acute vascular rejection from 27% to 8%. We conclude that acute coronary vascular rejection may be initially seen as global cardiac ischemia in the absence of significant interstitial myocardial rejection. Further, acute vascular rejection should be pathologically distinguished from chronic vascular rejection, although both are probably stages in the natural history of immune-mediated vascular injury.

Acute Disease↗
PubMedDate not supplied

Clinical and angiographic experience with intraoperative transluminal balloon-catheter dilatation and coronary artery bypass graft surgery.

Between April, 1980 and October, 1983, 40 patients with chronic stable angina pectoris underwent intraoperative transluminal balloon-catheter dilatation and coronary artery bypass graft (CABG) surgery. The main indication for this combined procedure was diffuse symptomatic coronary artery disease with at least one coronary artery having two or more areas of narrowing. Intraoperative dilatation was performed upon 42 coronary arteries involving 57 narrowed arterial segments where dilatation was attempted. The balloon-tipped catheter could not be passed through two stenotic sites. There was no documented perforation but unrecognized intimal injury was observed in two patients at postoperative catheterization. There was one perioperative myocardial infarction, one operative death and 97% early relief of angina pectoris. In 25 distal arterial narrowings that were studied angiographically in the early postoperative period (mean 10 days), 15 (60%) were unchanged, 2 (8%) were worse and 8 (32%) were improved compared to the preoperative angiogram. Patients with discrete narrowings did better than those who had balloon dilatation for diffuse narrowings; 49% of the former as compared to 17% of the latter had angiographic evidence for improvement. During the follow-up period (mean 30 months), three patients developed recurrent angina pectoris and one died of congestive heart failure. Thirteen distal arterial narrowings were studied angiographically late postoperatively (mean 12 months). In these 13 areas, 6 (46%) were unchanged, 3 (23%) were worse and 4 (31%) were improved compared to preoperative angiograms. Additionally, 10 arterial narrowings were observed angiographically, both early and late postoperatively. Nine of these serially observed segments remained unchanged while one became worse.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗