Robert B. Wray

Coronary angioplasty, atherectomy and bypass surgery in cardiac transplant recipients

OBJECTIVES This study sought to analyze the outcomes of revascularization procedures in the treatment of allograft coronary disease. BACKGROUND Allograft vasculopathy is the main factor limiting survival of heart transplant recipients. Because no medical therapy prevents allograft atherosclerosis, and retransplantation is associated with suboptimal allograft survival, palliative coronary revascularization has been attempted. METHODS Thirteen medical centers retrospectively analyzed their complete experience with percutaneous transluminal coronary angioplasty, directional coronary atherectomy and coronary bypass graft surgery in allograft coronary disease. RESULTS Sixty-six patients underwent coronary angioplasty. Angiographic success (< or = 50% residual stenosis) occurred in 153 (94%) of 162 lesions. Forty patients (61%) are alive without retransplantation at 19 +/- 14 (mean +/- SD) months after angioplasty. The consequences of failed revascularization were severe. Two patients sustained periprocedural myocardial infarction and died. Angiographic restenosis occurred in 42 (55%) of 76 lesions at 8 +/- 5 months after angioplasty. Angiographic distal arteriopathy adversely affected allograft survival. Eleven patients underwent directional coronary atherectomy. Angiographic success occurred in 9 (82%) of 11 lesions. Two periprocedural deaths occurred. Nine patients are alive without transplantation at 7 +/- 4 months after atherectomy. Bypass graft surgery was performed in 12 patients. Four patients died perioperatively. Seven patients are alive without retransplantation at 9 +/- 7 months after operation. CONCLUSIONS Coronary revascularization may be an effective palliative therapy in suitable cardiac transplant recipients. Angioplasty has an acceptable survival in patients without angiographic distal arteriopathy. Because few patients underwent atherectomy and coronary bypass surgery, assessment of these procedures is limited. Angiographic distal arteriopathy is associated with decreased allograft survival in patients requiring revascularization.

Postpartum myocardial infarction.

A 29 year old woman had a myocardial infarction three weeks post partum. Coronary angiography was performed six days later. No abnormalities were seen initially, but re-injection of the left coronary artery resulted in a dissection that extended through the anterior descending and circumflex branches and a reinfarction. This case suggests that myocardial infarctions occurring in patients with angiographically normal coronary arteries may be caused by dissections that heal by the time of catheterisation.

Balloon mitral valvuloplasty via retrograde left atrial catheterization

A technique for performing retrograde catheterization of the left atrium followed by double balloon mitral valvuloplasty without transseptal catheterization is described. Three patients have undergone double balloon mitral valvuloplasty by means of this technique, all with marked improvement in postdilatation mitral valve areas. The technique avoids iatrogenic atrial septal defects and is less difficult to perform than transseptal catheterization.

Comparison of three techniques for percutaneous balloon aortic valvuloplasty of aortic stenosis in adults

Three different techniques for percutaneous balloon aortic valvuloplasty h have been described: retrograde single balloon, retrograde double balloon, and antegrade techniques. This report describes our experience using the three techniques in twenty-five consecutive procedures. All techniques resulted in a significant decrease in transvalvular pressure gradient and an increase in calculated aortic valve area, without significant difference among the three. There was no increase in the degree of aortic regurgitation after valvuloplasty by any of the techniques. Vascular complications occurred only with the retrograde double balloon technique. Cardiac tamponade during balloon inflation occurred with both the retrograde single and double balloon techniques. Three deaths occurred; two during the antegrade technique and one after the retrograde double balloon technique. Thus, balloon aortic valvuloplasty can be effectively performed using any of the three techniques. However, the differing techniques have inherent advantages in specific situations, as well as potential complications.

Computer Estimation of Stroke Volume from Aortic Pulse Contour in Dogs and Humans

Stroke volume (SV) estimation from computer analysis of aortic pressure contour was tested in 12 anesthetized dogs and 2 humans with A-V block. The ‘actual’ SV was calculated from right-heart bypass pump flow values in 6 open-chest dogs, from heart rate (HR) and cardiac output (CO) using dye dilution in 6 closed-chest dogs and by the Fick method in the human subjects. SV changes were induced by changes in pacing rate and pump flow, infusion and withdrawal of fluids and exercise. Mean arterial pressure was altered in dogs by changes in CO and infusions of drugs.In the dogs, the method (using Warner’s formula) proved consistent (r = 0.774, p y. x = 3.82 ml) but inaccurate (slope = 0.386) in 627 comparisons. The same conclusions were reached in 11 human comparisons. The Kouchoukos formula showed similar problems. Corrections are suggested based on these results.

Pulmonary Artery Wedge Pressure Lability in the Bovine

Summary In 10 normal calves and 7 calves with brisket disease, injections of small volumes of normal saline into the wedged pulmonary artery catheter were shown to produce transient but significant increases in pulmonary-artery wedge pressure that could be reversed with isoproterenol. Whether this occurred at a pre- or post-capillary site or both could not be determined. The technical assistance of Mr. Don Anton and Filimon Ukradyha, Ph.D. is greatly appreciated.