Antony H.G. Roche

Long-term follow-up of patients with the antibiotic-sterilized aortic homograft valve inserted freehand in the aortic position.

A series of 252 isolated aortic homograft valves in 248 patients have been followed for 9 to 16.5 years (mean 10.8). The valves were sterilized in antibiotic solution and stored in a nutrient medium at 4 degrees C and were nonvital. There were 15 in-hospital deaths (6%) and a mortality of 2.7% in patients undergoing an elective first operation. Actuarial survival with the study valve in situ was 57% at 10 years and 38% at 14 years. Only 8.4% of the patients died late from homograft valve failure, chiefly because of failure to refer patients with endocarditis for reoperation or because reoperation was refused in elderly, frail subjects. Incompetence was the sole cause of valve failure and was due either to valve wear or endocarditis. Significant incompetence required reoperation. On actuarial analysis, freedom from significant incompetence for the entire group was 95% at 5 years, 78% at 10 years, and 42% at 14 years. Factors increasing the risk of significant incompetence due to valve wear on multivariate analysis were increasing donor valve age (greater than or equal to 55 years), recipient age (less than 15 years), and an aortic root diameter over 30 mm. Analysis of the patient group that excluded each of these variables (low-risk group), which comprised 61% of the study population, indicated freedom from significant incompetence due to valve wear of 98% at 5 years, 94% at 9 years, and 56% at 13 years.

Six year review of the results of freehand aortic valve replacement using an antibiotic sterilized homograft valve.

The long-term behavior of an antibiotic-treated homograft aortic valve inserted in a freehand fashion was assessed in 121 patients operated upon for aortic valve disease and followed from four to six and one-half years. There were seven hospital deaths (5.7%) and 30 late deaths, only one of which was related to the homograft valve. The six year survival was 69% (77% for single valve and 52% for multiple valve surgery). At six years 9% had important homograft aortic valve incompetence (HAVI) and most of these required reoperation. Important HAVI occurred in only 5% of patients with an aortic root diameter < 24 mm and in 38% of those with a markedly dilated or distorted proximal aorta (P < 0.01). The freehand aortic homograft was considered superior to prosthetic devices because of the absence of chronic anticoagulation, thromboembolism, sudden death from valve failure and significant obstruction in a small aortic root. With slightly restricted patient selection the valve failure rate is expected to fall to less than 1% per year.

Aortic Homograft Valve Replacement A Long-Term Follow-Up of an Initial Series of 101 Patients

An initial series of 101 patients with a homograft aortic valve has been reviewed from 4 to 6 years postoperatively. There were six hospital and 24 late deaths, eight of which were due to homograft valve failure. The 71 surviving patients were all symptomatically improved. Anticoagulants were not used, and emboli were thought not to originate from the valve.Important incompetence occurred in 27 patients and reoperation was undertaken in 17 of these. The causes were peripheral leaking of the suture line, cusp rupture, bacterial endocarditis, and valve misplacement.Leaflet calcification produced stenosis, requiring reoperation in two patients, and was significant in eight other valves. Precipitating causes, present in eight of the 10 cases, were imperfections in the original homograft, valve misplacement, or endocarditis.Both cusp rupture and leaflet calcification were related to the method of valve preparation as neither was encountered in untreated valves. For this reason, chemical sterilization and freeze drying have been replaced by sterilization and storage in an antibiotic Hanks solution.

Coronary surgery after recurrent myocardial infarction: progress of a trial comparing surgical with nonsurgical management for asymptomatic patients with advanced coronary disease.

A randomized trial of surgical vs nonsurgical management was carried out in men 60 years of age or younger who had recovered from a recurrent myocardial infarction. Of 205 patients considered, 100 had few or no symptoms and had coronary vessels favorable for bypass grafting; these patients fulfilled the trial conditions and were randomized (50 surgical and 50 nonsurgical). In 41 patients (elective nonsurgical group), randomization was not considered justifiable because of relatively unfavorable coronary anatomy or severe left ventricular dysfunction. Nineteen patients had elective surgery because of disabling angina despite full medical treatment or because of significant left main coronary stenosis. In 45 patients, coronary angiography was not undertaken because of medical contraindications or reluctance of the patient to enter the study.Actuarial survival curves (mean follow-up 4.5 years) show an annual mortality rate of 3–4% per year for all investigated patients, and no advantage for the randomized surgical over the randomized nonsurgical group. The results suggest that in the absence of disabling angina or left main coronary artery stenosis, coronary artery surgery need not be advised for survivors of recurrent infarctions who have severe coronary artery disease. Moreover, the prognosis for the group of patients not treated surgically appears to be better than has been previously described.

Ultrasonic imaging of the coronary arteries in open-chest humans: evaluation of coronary atherosclerotic lesions during cardiac surgery.

We explored techniques that would allow the surgeon to localize coronary artery lesions demonstrated angiographically or to supplement angiographic information in patients who are undergoing coronary artery bypass procedures by intraoperative scanning of the coronary arteries using ultrasound. A 9-MHz electronically focused water-path ultrasound scanner was first used to image the coronary arteries in three anesthetized, open-chest sheep. In a subsequent study, 10 human subjects undergoing cardiac surgery for valve replacement who had normal coronary angiograms were scanned during heart surgery to provide images of normal coronary arteries. The ultrasoundprobe was sterilized with gas and placed directly on the beating heart by the surgeon. In the third phase of this study, 21 patients with coronary artery disease were scanned and the ultrasonic appearance of their imaged coronary lesions was compared to independently interpreted angiographic estimates of percent obstruction, with close correlation (r = 0.91). The ultrasound scan could be used to identify lesions in vessels beyond proximal occlusions, which are not visualized well angiographically, and could localize thesite of lesions to determine placement of saphenous vein bypass grafts. This new technique may provide a method of evaluating coronary atheroscleroticlesions during coronary artery surgery and aid decisions regarding placement of saphenous vein grafts.

Late Regression of the Dilated Site After Coronary Angioplasty

Background Limited data are available on the changes that occur at the dilated site late after coronary angioplasty. The aim of this study was to evaluate with quantitative angiography the natural history of changes that occur in the dilated segment between “early” (≈6 months) and “late” (≈5 years) follow-up after angioplasty. Methods and Results Of 127 consecutive patients (174 lesions) with successful angioplasty, 125 underwent early angiography. Three patients subsequently died, and 24 underwent revascularization surgery or repeated angioplasty, giving a study-eligible population of 98 patients. Quantitative angiographic analysis was performed before and immediately after angioplasty and at early and late follow-up in the study population of 84 patients (115 lesions), which was 86% of study-eligible patients. Mean lesion diameter stenosis decreased from 36.3±14.2% at early to 29.6±13.5% at late follow-up (P<.0001). No lesion developed late restenosis by the 50% diameter loss criterion. Late regression ...

Doppler echocardiography in the assessment of the homograft aortic valve

To determine the utility of Doppler echocardiography in the evaluation of the homograft valve in the aortic position, 27 patients with normally functioning valves (group 1) and 30 patients with suspected malfunctioning valves (group 2) were examined. Simultaneous cardiac catheterization and Doppler echocardiography were performed in 23 group 2 patients. Doppler and surgical findings were compared in 7 patients too ill for invasive studies. In group 1 patients, the maximal velocity (+/- standard deviation) was 1.8 +/- 0.37 m/s, the mean pressure gradient was 7.1 +/- 3.07 mm Hg and the mean aortic valve area was 2.2 +/- 0.79 cm2. The maximal velocity in group 2 patients with aortic regurgitation (AR) classified as moderate or greater was 2.5 +/- 0.55 m/s, compared with 1.8 +/- 0.44 m/s in patients with mild AR or less (p less than 0.01). In the quantitation of AR, pulsed-wave mapping and angiographic grades were identical in 18 patients and differed by 1 grade in 5. Seven patients too ill for catheterization had severe destruction of valve leaflets at cardiac surgery. In 6 patients, both Doppler grading methods suggested severe AR. In a seventh patient, who had an obstructed Starr-Edwards valve in the mitral position, AR was graded as mild by pulsed-wave mapping. Only 1 patient had homograft valve stenosis, with a withdrawal gradient at catheterization of 34 mm Hg and a Doppler maximal gradient of 36 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of deterioration or infection of homograft and porcine xenograft bioprosthetic valves in mitral and aortic positions by two-dimensional echocardiographic examination

Results of two-dimensional echocardiographic examinations were compared with angiographic, hemodynamic and surgical results in 44 patients with bioprosthetic valves in mitral and aortic positions who were undergoing elective or urgent reinvestigation 24 to 87 months (mean 34) after implantation. In these patients, there were 18 homograft aortic valves in the aortic position, 9 stent-mounted homograft aortic valves in the mitral position, 13 porcine xenograft valves in the mitral position and 12 in the aortic position. Poor cusp support, gross fluttering and prolapse of cusps behind or below the anulus identified aortic insufficiency by two-dimensional echocardiography in six patients with an aortic homograft and four patients were identified with insufficiency of a stent-mounted aortic homograft in the mitral position. Two-dimensional echocardiographic examination revealed mitral stenosis in three patients with a porcine xenograft valve in the mitral position and suggested mitral insufficiency in two others. Bacterial endocarditis on homograft or porcine xenograft valves was associated with easily imaged vegetations by two-dimensional echocardiography in 10 patients. Despite difficulties in imaging valve cusps, and the skill required to obtain good echocardiographic images of bioprosthetic valves, significant valve deterioration or infected prostheses were quite effectively imaged by two-dimensional echocardiography in this study.

Doppler echocardiographic assessment of atrial filling fraction in severe mitral stenosis

Abstract When patients with mitral stenosis (MS) develop atrial fibrillation, symptomatic deterioration often occurs. This could be due to either loss of active atrial contraction or to the reduction in diastolic filling time caused by the tachycardia that is often present. Previous studies, using cardiac catheterization methods, have yielded conflicting results. 1–5 Recently Doppler echocardiography has been used to determine the contribution atrial contraction makes to ventricular filling in normal subjects and patients with a variety of cardiac diseases. 6 To date we are unaware of any Doppler studies in patients with MS.