Experience with the Mitroflow aortic bioprosthesis.

From October 1985 to May 1990, the Mitroflow bovine pericardial valve was placed in the aortic position in 168 patients (97 men, 71 women) with a mean age of 69.7 years. Eighty-nine patients had isolated aortic valve replacement, and 79 had aortic valve replacement and additional procedures. Follow-up over 7 1/2 years includes 781 patient years (426 for isolated aortic valve replacement). Mean follow-up time is 56 months. Peak-to-peak gradients (in millimeters of mercury) measured in the intraoperative period averaged 11.0 +/- 8.7, 11.8 +/- 10.8, and 8.6 +/- 8.2 for 19 mm, 21 mm, and 23 mm valves, respectively. Hospital mortality was 7.3% (14 patients); all deaths were non-valve related. Late mortality of 20.1% in 31 patients resulted from cardiac failure (n = 8), sepsis (n = 4), valve reoperation (n = 1), non-cardiac causes (n = 15) and sudden, unknown causes (n = 3). Fifteen thromboembolic episodes occurred, but only three late thromboembolic episodes occurred in isolated aortic valve replacement without other risk factors. Four early and four late episodes of endocarditis occurred. Seven patients had clinical valve dysfunction, and five others required reoperation for structural deterioration, with one death. At 94 months, overall survival was 64% +/- 5%. Freedom from thromboembolic episode was 87% +/- 3% and 90% +/- 4% for isolated aortic valve replacement. Freedom from combined reoperation or clinical dysfunction was 75% +/- 8%: 64% +/- 15% for those under 70 years of age, and 87% +/- 7% for those 70 years of age and older. The valve has favorable hemodynamics. Durability begins to decline during the sixth year after implantation, possibly at a slower rate in patients older than 70 years of age.

Unusual complication of porcine heterograft.

This paper discusses a complication that is associated with mitral valve replacement utilizing the porcine heterograft and that, to the best of our knowledge, has not been reported previously. Severe mitral insufficiency developed early in 2 patients following mitral valve replacement with a porcine bioprosthesis. Both patients required reoperation. In each patient, it was discovered that one of the cusps of the mitral prosthesis was in the fixed-open position with no evidence of perivalvular leak. The assumption was that failure of the leaflet to close properly had been present from operation. Careful inspection of the valve and assurance that all leaflets close properly should be made at the time of initial valve replacement.

Early postoperative spasm in left internal mammary artery bypass grafts.

Two patients with early postoperative spasm of a left internal mammary artery bypass graft are described. To our knowledge, this entity has not been reported previously. Both patients were characterized by vasomotor collapse secondary to intractable spasm responsive only to local application of vasodilator agents. Although the mechanism of graft spasm is not clear, prophylactic nifedipine therapy in appropriate dose may be of some value. The profound hemodynamic effect of internal mammary artery spasm in the immediate postoperative period may allow no time for anything other than emergency reoperation to assess the nature of the problem and treat it appropriately.

Repair of coronary sinus rupture secondary to retrograde cardioplegia.

Coronary sinus injuries related to retrograde cardioplegia administration are uncommon, but can be a lethal complication of this technique. This report describes a major coronary sinus disruption during retrograde cardioplegia administration and details a method of repair with suggestions for possible prevention of this complication.

Use of the centrifugal flow pump for vena caval shunting.

We have used the Bio-Medicus centrifugal flow pump for vena cava shunting during surgical resection of renal cell carcinoma with extension of the tumor into the inferior vena cava. The active shunt can provide optimal blood return to the heart to promote hemodynamic stability, help provide an isolated field for resection of the involved kidney and its tumor extension into the vena cava, and avoid use of full-dose heparin to minimize blood loss in this extensive operation.

Simplified method for reoperation on the mitral valve.

Reoperation on the mitral valve is becoming more common because of the degeneration of bioprosthetic valves, endocarditis, and malfunction or thrombosis of mechanical valves. We advocate a technique that transforms a technically difficult operation into one that is much less tedious, time-consuming, and dangerous than reopening a sternal-split operative site the second, third, or fourth time. Favorable experience in 11 patients using right anterolateral thoracotomy without aortic or right atrial cannulation and without aortic cross-clamping or cardioplegia is presented.

Malignant renal tumor with extension to the inferior vena cava.

BACKGROUND: Management of malignant renal tumors involving the inferior vena cava (IVC) depends on tumor extension within the cava. METHODS: Of 295 patients treated for renal cancer, propagation of tumor mass through the renal vein to IVC was seen in 22 (7%) patients. Cephalad extension of the tumor was suprarenal: infrahepatic in 12, retrohepatic in 6, and within the right atrium in 4 patients. All patients had radical nephrectomy, cavotomy, and complete resection of tumors except 1 with diffuse peritoneal metastasis. RESULTS: Twenty-one patients had curative resections. No operative deaths and no instances of pulmonary embolism or exsanguination occurred. Seventeen patients were alive at 2 years and 12 at 5 years, resulting in 77% and 55% survival rates, respectively. CONCLUSIONS: An aggressive approach for vena cava involvement from malignant renal neoplasms resulted in prevention of tumor embolus, minimization of blood loss, and maintenance of venous return to the heart.

Coronary revascularization in young patients.

From 1978 to 1982, 92 of our 1704 patients undergoing coronary bypass surgery were 40 years of age or younger. Eighty-six were male and six were female. The main indications for surgery were refractory angina and unstable angina. A family history of heart disease, smoking, and hypertension were major risk factors. The majority of patients had triple vessel disease, and six had left main lesions. Left ventricular function was moderately or severely impaired in 24. Coronary revascularization was performed with internal mammary and saphenous vein conduits, with a mean of 3.7 grafts per patient (range, 1 to 7). There was no operative mortality, but one patient required an intraaortic balloon pump. Perioperative infarction determined by Q waves occurred in one patient, while eight had enzymatic evidence of infarction. Late follow-up to 60 months showed three late deaths of cardiac origin. Eighty-three survivors were greatly improved, and 50 were asymptomatic. Sixty-five patients returned to work. Seventy percent of smokers stopped smoking; half the patients exercised regularly, and half maintained dietary modifications. Coronary bypass grafting is an effective rehabilitation procedure in the young. Long-term attention to risk factors and life style is required to maintain a beneficial outcome.

Delayed sternal closure as a safe adjunct to support biventricular failure after open heart surgery.

Over a four-year period, 22 patients of 2495 undergoing open heart surgery sustained severe biventricular failure (BVF) and would not tolerate primary sternal closure. Reasons for BVF included intraoperative injury, perioperative infarction, global dysfunction, cardiopulmonary edema, and intractable arrhythmia. Mechanical assist devices were required in nine patients. Average cardiac index fell to 1.1 L/min/m2 with attempts to close the chest, then stabilized at 1.9 with the sternum open and only soft tissue closed. After 3 to 11 days, cardiac index rose to 2.5 when assist devices were removed, inotropic agents decreased, and the sternum closed. Three early deaths (5-12 days) were caused by progressive biventricular failure. Five later deaths (19-64 days) were associated with renal and respiratory failure, superinfection, and sepsis. All of these required tracheostomy. Survival of 14 patients was not related to early low cardiac output, preoperative status, timing of sternal closure, or age, but was associated with early recovery of respiratory function without need for tracheostomy, avoidance of renal failure, and satisfactory alimentation. Sternal infection occurred in three patients, resulting in one death. The hospital stay ranged from 12 to 230 days. There was one death resulting from respiratory failure 14 months postoperatively. Our findings show that delayed sternal closure lessens early cardiac instability during BVF, helps allow recovery, and does not produce long-term disability.

Primary cardiac tumors. Diagnosis and management in 14 cases.

In our experience over a 10-year period at Westchester County Medical Center (Valhalla, NY), we diagnosed 11 left atrial myxomas and three primary cardiac malignancies in ten females and four males, aged 18-74 years. Two-dimensional echocardiography enabled the correct diagnosis of these lesions. Detailed characteristics of the cardiac tumors were provided by magnetic resonance imaging (MRI) scanning in five patients. Two of three malignancies were only biopsied; the myxomas were completely excised. We emphasized removal of tumor and its attachments to the atrial wall, accomplished by left or biatrial incision, full-thickness excision of the area of attachment, and pericardial patch closure of the atrial or free-wall defects. Associated procedures included mitral valve repair (three) and coronary artery bypass grafting (two). There was no mortality associated with the surgery. Two patients with malignancy died three and 36 months after surgery; a third is alive at 30 months after surgery. No patients with myxoma has had recurrence from 16 to 100 months. Preoperative diagnosis of cardiac tumors is enhanced by MRI scanning and may help in planning the surgical procedure. Complete and timely removal of these tumors contributes to long-standing patient survival.