Sutureless Valve in Repeated Aortic Valve Replacement: Results from an International Prospective Registry

OBJECTIVE

To report early and midterm results registry of patients undergoing repeated aortic valve replacement (RAVR) with sutureless prostheses from an international prospective registry (SURE-AVR).

METHODS

Between March 2011 and June 2019, 69 patients underwent RAVR with self-expandable sutureless aortic bioprostheses at 22 international cardiac centers.

RESULTS

Overall mortality was 2.9% with a predicted logistic EuroSCORE II of 10.7%. Indications for RAVR were structural valve dysfunction (84.1%) and infective prosthetic endocarditis (15.9%) and were performed in patients with previously implanted bioprostheses (79.7%), mechanical valves (15.9%), and transcatheter valves (4.3%). Minimally invasive approach was performed in 15.9% of patients. Rate of stroke was 1.4% and rate of early valve-related reintervention was 1.4%. Overall survival rate at 1 and 5 years was 97% and 91%, respectively. No major paravalvular leak occurred. Rate of pacemaker implantation was 5.8% and 0.9% per patient-year early and at follow-up, respectively. The mean transvalvular gradient at 1-year and 5-year follow-up was 10.5 mm Hg and 11.5 mm Hg with a median effective orifice area of 1.8 cm²and 1.8 cm², respectively.

CONCLUSIONS

RAVR with sutureless valves is a safe and effective approach and provides excellent clinical and hemodynamic results up to 5 years.

Heart lymphoma 6 years after a prosthetic ascending aorta replacement: related or unrelated?

An highly malignant B-cell lymphoma developed acutely 6 years after replacement of the aortic root with a Dacron prosthesis, involving the heart and the adjacent mediastinum. Rapid clinical deterioration and absence of early histological confirmation led to exploratory unsuccessful surgery. This case illustrates the rapid evolution of some of these tumours and raises again the hypothesis of the carcinogenic potential of Dacron material.

[Congenital pericardial defect associated with coronary artery disease: surgical treatment]

The case of a 62-year-old patient presenting with exertional chest pain, atheromatous coronary lesions and left congenital pericardial defect is reported. The diagnostic of peri cardial defect was evoked in relation with a long-known asymptomatic cardiac left malposition and confirmed at surgery. Clinical presentation, diagnosis and management of congenital pericardial defects are discussed.

[Remodelling the aortic root by resection of the ascending aorta and non-coronary sinus in annular dilatation of the aorta and acute dissection of the descending aorta. 29 observations]

The first conservative surgical procedures of the native aortic valve in annular dilatation were performed by Yacoub and David [1, 2]. These so-called remodelling and inclusion procedures provided hope for a normal life without long-term anticoagulant therapy for patients with Marfan's syndrome, with protection from the complication of an acute dissection of the ascending aorta. The authors reported their experience in the Archives des Maladies du Coeur et des Vaisseaux in 1999, with excellent results [3]. However, a certain number of cases are encountered in which the Yacoub and David procedures cannot be performed because of the presence of a pseudo-bicuspid valve, isolated asymmetrical dilatation of the non-coronary sinus or acute dissection of the aorta without dilatation of the aortic root. In these forms, the authors have developed a technique of remodelling the aortic root with conservation of the native valve by resecting the ascending aorta and non-coronary sinus, rather than carrying out a Bentall procedure. Twenty-nine cases of this type have been treated in this way for three different indications: aneurysm of the ascending aorta with bicuspid aortic valve, aneurysm of the ascending aorta with aortic insufficiency and extension to the posterior sinus, and type A acute dissection of the aorta.

Papillary fibroelastoma of a mitral valve chorda

A 43-year-old woman presented with an ischemic stroke in the right middle cerebral artery territory. Cardiac echography disclosed a tumor of a primary chordae of the anterior leaflet of the mitral valve. After neurologic recovery, the patient was referred to surgery for excision of the tumor and plastic reconstruction using a chordal transfer technique. Histological examination of the tumor showed a typical papillary fibroelastoma. Papillary fibroelastoma is the third most frequent cardiac benign tumor. The high embolic potential of this tumor is in favor of an aggressive surgical attitude.

Results of an exclusion technique for treatment of abdominal aortic aneurysm

An exclusion technique for the treatment of abdominal aortic aneurysm was used in six patients considered to be at high operative risk mainly because of chronic pulmonary disease. There were no deaths or immediate major complications. Thrombosis of the aneurysm was achieved in four of the six patients. However, in three cases, repeated percutaneous embolization was required to produce thrombosis. One patient developed a secondary rupture of a persisting infrarenal sac resulting from a patent inferior mesenteric artery. This patient was successfully managed by ligature of the infrarenal portion of the abdominal aorta through a median laparotomy. This study emphasizes the limits and the risks of the exclusion technique.

Surgical treatment of Barrett's carcinoma. Correlations between morphologic findings and prognosis

Barrett's carcinoma occurred in 66 of 331 patients with adenocarcinomas of the esophagus or gastroesophageal junction. Only 32 (46%) of these patients had a history of gastroesophageal reflux. A history of alcohol and tobacco abuse was absent in 50% and 47.5%, respectively. The mean length of Barrett's metaplasia was 7.37 cm. Operability was 98.5% and resectability 95.5%. No postoperative or hospital deaths occurred. Pathologic staging was as follows: stage 0 and I, 38.3%; stage II, 20.6%; stage III, 22.2%; and stage IV, 19%. Overall survivals were 80.5% at 1 year, 62.7% at 2 years, and 58.2% at 5 years. Five-year survival for patients with stage I disease was 100%; for stage II, 87.5%; for stage III, 22.2%; and for stage IV, 0%. Thirty-four (51.5%) patients were under surveillance for a related or unrelated condition before diagnosis of their carcinoma; only nine (26.5%) had diseased lymph nodes. In 32 the diagnosis was made at their first medical contact, and 78% of them had diseased lymph nodes. Five-year survival without nodal metastasis was 85.3% and significantly better than for patients with metastasis, 38.3% (p = 0.0033). Of the 66 patients, 19 (28.7%) had a biopsy-proved history of Barrett's metaplasia before malignancy developed. Mean time interval between diagnosis of metaplasia and degeneration was 3.8 years (89.5% > 1 year). Over the surveillance period, the length of metaplastic Barrett's esophagus remained unchanged in all patients. Barrett's ulceration was present from the beginning in 14 patients, and three patients never had an ulcer. Intestinal metaplasia was seen in 18 patients. Resected specimens revealed severe dysplasia in 16 patients. Of the 19 patients, 73.7% had stage I disease. Our data suggest that close endoscopic monitoring and systematic biopsies of the smallest irregularities in the metaplastic mucosa may result in early detection of carcinoma. In this respect, patients with an ulcer within a zone of intestinal metaplasia seem to be at risk. Early detection increases substantially the chances for cure by diminishing the risks of lymph node involvement. Resection remains the treatment of choice in Barrett's adenocarcinoma including high-grade dysplasia, because mortality can be kept low with excellent to very good functional results in the majority of the patients provided the intervention is performed by experienced teams.

Analysis of endotoxin effects on pulmonary circulation in terms of pressure-flow characteristics

The purpose of the present work was to explore the hypothesis that pulmonary vasoconstriction secondary to endotoxin insult results mainly from an increase in the critical closing pressure of the pulmonary vessels. Specifically, we reasoned that in the face of a Starling resistor located between pulmonary arteries and left atrium, upstream transmission of increased left atrial pressure (Pla) would be inversely related to the level of the pressure intercept (Pi) obtained by extrapolation from the linear pulmonary arterial pressure (Ppa)--flow (Q degrees) plot. Six dogs (group E) were infused with Escherichia coli endotoxin (0.25 microgram/kg/min) for 2 hr, whereas six additional dogs (group C) served as control. During baseline conditions, Pi approximated LAP in both groups. In group C dogs, increasing LAP at constant Q degrees led to a proportional augmentation of Ppa. In group E dogs, endotoxin resulted in a shift of the Ppa-Q relationships to higher pressures due to both increases in Pi and slope. In addition, changes in Pla over the same range as in control dogs affected Ppa only at the highest levels of Pla. We conclude that endotoxin insult increases the critical closing pressure that exceeds Pla and induces the occurrence of a Starling resistor responsible for the production of an effective vascular waterfall.

Pressure-flow relationships of the pulmonary circulation during endotoxin infusion in intact dogs

BACKGROUND AND METHODS

We aimed to characterize the effects of an endotoxin insult (Escherichia coli 0127:B8) on the relationships between pulmonary vascular pressure and flow in intact dogs. To achieve this goal, multipoint plots of total pressure gradient, arterial pressure gradient, and venous pressure gradient vs. flow were generated by graded inflation of a right atrial balloon, which was used to vary flow. The partitioning of the total pressure decrease across the pulmonary vasculature (total pressure gradient = pulmonary arterial pressure-pulmonary artery occlusion pressure [PAOP]) into gradients across pulmonary arterial (arterial pressure gradient = pulmonary arterial pressure--effective capillary pressure) and pulmonary venous (venous pressure gradient = effective capillary pressure--PAOP) regions was assessed by a waveform mathematical analysis of the pulmonary arterial pressure profile during arterial occlusion, with computation of both PAOP and effective pulmonary capillary pressures. Slopes and extrapolated pressure intercepts from linear regression fits to the pulmonary vascular pressure/flow plots were determined in seven dogs after a 2-hr endotoxic infusion interval and were compared with the corresponding values that characterized a similar group of sham-operated dogs.

RESULTS

Under normal conditions, the extrapolated pressure intercept for pulmonary arterial pressure gradient was virtually 0 mm Hg; for total pulmonary arterial pressure gradient and pulmonary venous pressure gradient, the mean extrapolated pressure intercepts were substantially positive: 2.4 +/- 0.2 and 2.1 +/- 0.3 mm Hg, respectively. Endotoxin infusion at 0.25 micrograms/kg/min significantly increased the pressure intercepts from 2.4 to 8.7 and from 2.1 to 8.3 mm Hg of total pressure gradient and venous pressure gradient vs. flow, respectively. This infusion produced a minor, nonsignificant change in the intercept of arterial pressure gradient vs. flow, whereas it increased its slope significantly (p less than .05) from 0.036 to 0.081 mm Hg/mL/min/kg.

CONCLUSIONS

These data suggest that endotoxin's effects on vascular resistance are exerted at two different loci such that these effects are additive. These endotoxin-induced effects consisted of increased vascular resistance of the arterial segment and appearance of a Starling resistor at the venous side of the pulmonary circulation, which acted as the relevant back-pressure to flow.

Identification of three-element windkessel model: comparison of time and frequency domain techniques

The problem of the parameter identification of the three-element windkessel model is studied. Minimization by least-square technique--LSQ--in time domain and frequential techniques--FFT--are compared. Continuous pressure and flow curves were recorded in the proximal aorta of an open chest dog. Comparison shows very high correlations between the parameter estimations obtained by LSQ and FFT methods. However, systematic differences appear between the calculated values, but do not seem to endanger physiological interpretation of the results.

Antimitotic activity of strychnopentamine, a bisindolic alkaloid

Strychnopentamine has been tested for its cytotoxic and antitumor activities and compared with two other bisindolic alkaloids that possess an usambarane skeleton. The presence of a N-methylpyrrolidine group increases the antimitotic activity of this type of alkaloids.