Hemodynamics and early performance of the St. Jude Medical Regent aortic valve prosthesis.

BACKGROUND AND AIM OF THE STUDY: The St. Jude Medical (SJM) Regent heart valve is a new bileaflet prosthetic valve modified from the currently marketed SJM mechanical valve, with a modified external profile that results in a larger geometric orifice area without changing the existing design of the pivot mechanism or blood contact surface areas. The aim of the present study was to report the early hemodynamic and clinical results of an on-going multicenter trial investigating the clinical performance of the Regent mechanical aortic valve prosthesis. METHODS: The early results from 204 patients at 11 centers in North America and Europe who underwent implantation of a Regent mechanical aortic valve prosthesis are described. Clinical status was prospectively recorded, and echocardiography with Doppler performed at hospital discharge, and at two and six months and one year postoperatively. RESULTS: Follow up to date is 109.3 patient-years (average follow up 0.5+/-0.4 years per patient; range: 0 to 1.7 years). NYHA class improved for the group, and there were low rates of clinical adverse effects. Echocardiographic mean pressure gradient at six months was 13.8+/-10.3, 7.4+/-4.1, 5.4+/-3.2, 5.2+/-2.8, 3.4+/-2.3 and 3.6 mmHg, respectively, for 19, 21, 23, 25, 27 and 29 mm valves; effective orifice area was 1.5+/-0.6, 2.0+/-0.7, 2.4+/-1.0, 2.5+/-0.7, 3.6+/-1.4 and 4.8 cm2, respectively. There was a statistically significant decrease in left ventricular mass index between early postoperative (169.1+/-57.7 g/m2) and six months follow up (137.2+/-42.7 g/m2, delta = -30.1+/-42.5 g/m2, p <0.0001). CONCLUSION: The SJM Regent aortic valve has excellent associated hemodynamics with rapid and significant left ventricular mass regression. In all cases of adverse events, rates fell within Objective Performance Criteria guidelines. Long-term clinical assessment is on-going.

Coronary artery bypass and valve replacement in octogenarians.

A total of 325 patients, aged 80 to 92 (mean 82), underwent cardiac operations with cardiopulmonary bypass over a 4-year period (1991-1995). Hypothermia (22 degrees C) and hyperkalemic cardioplegia were used in each. Coronary bypass procedures only (Group I) were performed in 255 patients with 22 early deaths (8.6%), and the average number of grafts was 3.7 per patient. Single or double valve replacement, with coronary bypass (Group II) was performed in 46 patients, with six early deaths (13%). Single or double valve replacement, without coronary bypass (Group III) was performed in 24 patients, with two early deaths (8.3%). Total hospital mortality was 30 deaths in 325 patients (9.2%). Fifty-six procedures (22%) from Group I and four (9%) from Group II were performed as emergencies, and all operations in Group III were elective. Seventy-two patients (27%) from Group I, 18 patients (39%) from Group II, and nine patients (37%) from Group III had major complications including renal failure, cerebrovascular accident, myocardial infarction, postoperative hemorrhage, sepsis, and ventilatory dependency. Mean hospital stay was 10.5 days for Group I, 13.3 days for Group II, and 15.2 days for Group III, with an overall mean of 13 days (range, 6-52) days. Higher mortality was related to a cardiac index <1.8, cardiogenic shock, emergency operation, creatinine >2.0, and morbid obesity. Mean left ventricular ejection fractions were 0.51 for Group I, 0.45 for Group II, and 0.49 for Group III. Preoperative risk factors associated with a higher mortality included hypertension, smoking, diabetes, and pulmonary hypertension. Two hundred seventy-two of the 299 operative survivors were followed for a mean of 18 (range, 3-52) months. The actuarial survival of octogenarians is 92 per cent, 80 per cent, and 65 per cent at 1, 3, and 5 years, respectively, and of the patients surviving operation it was 85 per cent, 70 per cent, and 55 per cent at 1, 3, and 5 years, respectively. At postoperative follow up, 80 per cent of the survivors reported an active functional status, and there was a low incidence of cardiac-related deaths.

Repair of a coronary pseudoaneurysm with percutaneous placement of a saphenous vein allograft attached to a biliary stent.

Late coronary artery pseudoaneurysm formation is a rare complication of perforation following percutaneous intervention. While surgical intervention is the treatment of choice for large expanding pseudoaneurysms, the optimal treatment strategy for small-to-moderate pseudoaneurysms is unclear. We describe the percutaneous placement of a saphenous vein allograft for treatment of a coronary artery pseudoaneurysm presenting as a late complication of coronary perforation.

Surgical therapy for the patient with internal carotid artery occlusion and contralateral stenosis.

With demonstration of the failure of extracranial-intracranial (EC-IC) bypass to reduce the incidence of stroke in patients with internal carotid artery (ICA) occlusion, controversy continues regarding the best method of stroke prevention in these high-risk persons. One approach, endarterectomy of stenotic lesions of the contralateral carotid bifurcation, has been used for 145 patients with ICA occlusion during the past 25 years. Presenting symptoms included focal transient ischemic attacks (TIAs) in 62 patients, stroke (CVA) in 57, and nonfocal TIAs in 16. Ten patients were asymptomatic. Nine patients (6.2%) sustained perioperative strokes, only three of which were ipsilateral to the endarterectomy. There were three perioperative deaths (2.1%). During the follow-up period (mean 4 years) there were 13 new strokes (9.2%), four of which were fatal. These late results compare favorably with patients from the cooperative study of EC-IC bypass with occlusion of one ICA, whether they received surgical treatment or were managed nonoperatively. With the exception of select situations where an occluded ICA may be reopened, we conclude that the best current therapy for these patients is close observation of the nonoccluded ICA and endarterectomy once a stenotic lesion is encountered.

Surgical management of the patient with bilateral internal carotid artery occlusion.

The patient with bilateral internal carotid artery occlusion is at high risk for development of stroke. Medical management and extracranial-intracranial bypass do not appear to offer these patients any protection from symptoms of cerebrovascular insufficiency. Our initial treatment in 11 of 12 patients who had this pattern of extracranial arterial occlusion has been external carotid artery revascularization. Nineteen procedures were performed for symptomatic lesions in all cases except one. There were no perioperative strokes or deaths. During a mean follow-up of 44.7 months, no new strokes occurred. Among 10 patients undergoing external carotid artery revascularization alone, only one transient ischemic attack occurred in follow-up. Seven of the eight surviving patients are presently asymptomatic. External carotid artery revascularization may be an effective and durable treatment for the patient with bilateral internal carotid artery occlusion.