Percutaneous recanalization of a renal artery in aortic dissection.

Chronic renal failure acutely worsened in a patient with a type B aortic dissection. Aortography revealed an occlusion of the left renal artery without renal intimal tear. Percutaneous recanalization, performed with a self-expandable stent, resulted in improvement in the renal function. This technique offers a new therapeutic choice in patients with visceral complications of aortic dissection.

Hemodynamic evaluation of heterotopic heart transplantation.

To assess the relative contribution of native and donor hearts to total circulatory performance after heterotopic transplantation, we used cardiac catheterization to examine 10 patients. Left and right ventricular filling pressures significantly decreased by 41% and 36%, respectively, cardiac index increased by 25%, and pulmonary arteriolar resistance was reduced by 61%. Patients were subdivided into two groups according to the presence of one (group I) or two (group II) peaks on the aortic pressure curve. In group I, the donor left ventricle assumed total left ventricular work and 80% of right ventricular work. Because the native left ventricle could not generate enough pressure to open the aortic valve, its entire stroke volume was ejected into the common left atrium. In addition, in all four patients a native aortic regurgitation occurred in diastole and systole. In contrast, in group II, native left ventricular systolic pressure always exceeded aortic diastolic pressure. The donor left ventricle contributed 68% to systemic blood flow and the donor right ventricle 51% to pulmonary blood flow. Mild native aortic regurgitation was demonstrated in two patients only. Native left ventricular function deteriorated postoperatively in all patients (ejection fraction decreased from 0.22 +/- 0.09 to 0.14 +/- 0.08), but this deterioration was more marked in group I. Postoperative depression of native left ventricular function could not be ascribed to progression of coronary artery disease but was mainly due to reduced preload (competitive filling) and increased afterload. Thus in group I patients with more severe preoperative left ventricular dysfunction, the donor heart behaved like a total biventricular assist device. In contrast, in group II patients the donor heart acted like a partial biventricular assist device.

[Our experience with bioprostheses in French Polynesia. A follow-up study from 1975 to 1988]. / L'expérience des bioprothèses en Polynésie française. Suivi de 1975 à 1988.

French Polynesia has unique social, cultural and geographic features. The prevalence of acute rheumatic fever (ARF) of 1.2 % population justified the health authorities' classification of this endemic as "major, severe, and prioritary" in 1984. Seventy per cent of patients with ARF develop cardiac sequellae which require surgery in 25 per cent of cases. Bioprostheses were considered from 1975 as the ideal valve replacement for these young, often undisciplined patients with no facilities for haemostatic control. Reoperation for valve degeneration has been increasingly frequent since 1982 and poses an acute problem leading to this statistic study and to a reflection as to the value of continuing to use this type of valve in this population. Analysis of 178 Polynesians with one or more cardiac bioprostheses in 1988, totalling 221 valves with a mean follow-up of 55 months, shows an actuarial survival rate excluding operative mortality of 86.7 +/- 3 % at 5 years (93.8 +/- 2.5 % in patients under 25 years of age, p = 0.001). Fifty-two patients (29 %) have been reoperated with a probability of being free of reoperation at 5 years of 70.1 +/- 4.2% (85.2 +/- 3.9 % in patients over 25 years of age and 43.8 +/- 7.8 % in patients under the age of 25, p = 0.002). The authors discuss the alternative of bioprostheses in this population : mechanical valves with anti-coagulant or anti-aggregant therapy, frozen aortic homografts, mitral valvuloplasty.

[Mid-term results of heart valve replacement with 2 types of pericardial heterograft. Apropos of 208 cases]. / Résultats à moyen terme du remplacement valvulaire à l'aide de deux types d'hétérogreffes péricardiques. A propos de 208 patients.

Medium-term results of valve replacement with a pericardial bioprosthesis were analysed in 141 patients receiving an Ionescu-Shiley aortic prosthesis and in 67 patients receiving a Mitroflow aortic (42), mitral (21) or double mitro-aortic (4) bioprostheses. There were 8 deaths in the operative (5.7%) and medium term (56 months) follow-up periods in the Ionescu group and a cumulative survival of 625 patient-years. There were 16 late deaths, 8 of cardiac origin. The 8 year survival and good functional results rates were 71% and 53% respectively. The linear rates of thrombo-embolism, endocarditis, reoperation, valvular dysfunction and regurgitation were 3.5, 1.1, 2.6, 2.7 and 6.1% patient-years. The corresponding figures in the Mitroflow bioprostheses were 0.5, 1.0, 3.1, 3.1 and 5.6% patient-years, but the average follow-up was shorter (36 months) with a cumulative survival of 195 patient-years. These results underline the frequency of primary valve dysfunction the mechanisms of which are: early tear in areas of high mechanical stress and late calcification. However, the hemodynamic profiles of this type of prosthesis are better than those of porcine bioprostheses which make them a valuable alternative in elderly patients operated for calcific aortic stenosis with a small aortic ring.