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R Cossette

Publications and source records attributed to R Cossette.

At least 19 recordsLinked to original sources
PubMed1998

Mitral valve repair: Intermediate to long-term echocardiographic follow-up.

OBJECTIVE: To review intermediate to long term echocardiographic follow-up after mitral valve repair for mitral regurgitation. DESIGN: Nonrandomized, retrospective and prospective observational study. SETTING: Sacré-Coeur Hospital, University of Montreal, Montreal, Quebec. PATIENTS: Echocardiographic findings in 37 patients (mean age 62.1 +/- 10 years) three to 197 months (median 45) after mitral valve repair were reviewed. INTERVENTIONS: Preoperative data were collated from hospital records. Between October 1994 and March 1995, all patients had a clinical evaluation and a complete transthoracic echocardiogram done by a cardiologist. RESULT: There was a significant reduction in the dimensions of the left-sided cavities compared with preoperative data. Left atrial diameter decreased from from 50.9 +/- 7.7 to 46.3 +/- 8.1 mm (P = 0.01), left ventricular end-diastolic diameter from 59.6 +/- 7.1 to 51.2 +/- 6.3 mm (P < 0.001) and left ventricular end-systolic diameter from 35.3 +/- 7.9 to 32.8 +/- 7.8 mm (P = 0.07). On colour Doppler echocardiography, nine patients had no mitral regurgitation, 25 had mitral regurgitation grade I to II/IV, and three had grade III/IV. The mean mitral valve gradient was 4.2 +/- 1.8 mmHg and the pressure half-time 121.9 +/- 48 ms. There was no difference in gradient, mitral valve area and mitral regurgitation in patients with degenerative (29) compared with rheumatic (five) mitral valve disease. CONCLUSIONS: Mitral valve repair is highly effective in reducing mitral regurgitation in the long term and is associated with a reduction in the dimensions of the left atrium and the left ventricle. However, it leaves a mild degree of mitral valve obstruction.

Aged↗
PubMed1997

Are intraaortic balloons suitable for reuse? A survey study of 112 used intraaortic balloons.

To assess the safety of reusing single-use intraaortic balloon devices (IABs), 112 used devices were investigated in terms of physical integrity, gas leakage inspection, mechanical performance, surface chemistry and morphology, and physical stability. These IABs were all used clinically only once, and the duration of the IABs in vivo ranged from 6 to 312 h. Macroscopic examination of the balloons and the outer catheters revealed no obvious change in either shape or color. No discernible abrasions or cracks were observed on the balloons. However, 61% of the balloons were creased, and 40% of the central lumens and 21% of the sheaths showed visible bending flaws. Moreover, 65% of the balloons and 38% of the central lumens were contaminated by visible residual organic debris. The physical integrity of each device was verified in a specially designed leakage-fatigue tester for 72 h. Ninety-seven percent of the devices passed the leakage inspection. Stress-strain testing, differential scanning calorimetry, attenuated total reflection-Fourier transform infrared, and scanning electron microscopy analyses clearly indicated that there were no significant differences in the mechanical properties, bulk material morphology, surface chemistry, and external surface morphology between the used balloons and virgin controls. Although some surface modifications occurred on the internal side of the balloons, the external surfaces of most balloons suffered no trauma. Most of the used IABs examined in this study maintained physical and mechanical properties similar to those of the virgin devices. The chemistry of the balloon material was stable after short-term in vivo use. However, it does not seem possible to establish a rigorous protocol of cleaning, sterilization, and inspection to guarantee a safer reuse of these devices. The presence of residual organic debris that cannot be eliminated results in an imperative preclusion not to reuse the IABs.

Calibration↗
PubMed1996

[Development of circulatory support during 420 aneurysm resections of the descending thoracic aorta].

From July 1974 to January 1996, 420 aneurysms of the descending thoracic aorta were surgically treated at l'Hôpital du Sacré-Coeur de Montréal. Three principles were previously established and rigorously respected: 1) the preservation of distal body perfusion, 2) the briefest aortic cross-clamp time realizable (mean: 29.8 +/- 16 minutes overall, reduced to a mean of 24 +/- 6 minutes for the last 250 cases), 3) keep the aortic resection as short as possible in order to preserve as many intercostal arteries as possible (10 cm or less in 91.6% of the cases). In the first 380 cases, distal aortic circulation was supported with a 9 mm Gott shunt without using systemic heparinization. Average shunt flows from 300 ml/min, to 4900 ml/min. (mean: 2497 +/- 813 ml/min.), average proximal pressures from 80 to 200 mmHg (mean: 146 +/- 17 mmHg) and average distal pressures from 15 to 150 mmHg (mean: 64 +/- 19 mmHg) were recorded. In the last 40 cases, the distal circulation was supplied through the left heart assistance device Bio-Medicus using minimal systemic heparinization (0.5 mg/kg), (target ACT > 150 seconds). Average pump flows from 1800 ml/min to 5200 ml/min. (mean: 3340 +/- 866 ml/min.) were obtained. Average proximal pressures from 90 to 200 mmHg (mean: 118 +/- 19 mmHg) and average distal pressures from 58 to 180 mmHg (mean: 95 +/- 24 mmHg) were recorded. Overall hospital mortality is 11.9% (50/420 cases) and 9.9% when ruptured aneurysms are excluded. Paraplegia occurred in 2 patients (0.4%) and one was related to an unfunctional Gott shunt. Adverse anatomical conditions like a proximal aneurysm, degenerative changes of the aortic wall, a previous proximal graft replacement or the presence of coronary artery bypass grafts, a friable wall encountered with dissecting aneurysms and also an adverse physiological condition like a left ventricular dysfunction prompted us to modify the circulatory support by using the left heart bypass. Comparison of both methods of perfusion supported by statistical analysis regarding shunt and pump flows, proximal and distal perfusion pressures has showed the physiological superiority of the centrifugal pump that we have now routinely adopted.

Adolescent↗
PubMed1995

Aneurysms of the descending thoracic aorta: three hundred sixty-six consecutive cases resected without paraplegia.

PURPOSE: The aim of this study was to present a 20-year experience with a single method of passive distal perfusion during descending thoracic aortic aneurysm resection. METHODS: Aortic repair with a Dacron graft interposition was performed for 366 consecutive aneurysms located between the left subclavian artery and the crux of the diaphragm. The extent of aorta resected in 335 patients (91.5%) represented one third or less of the aortic length. A 9 mm Gott shunt was cannulated proximally into the ascending aorta (235 cases), the aortic arch (60 cases), the descending aorta (68 cases), or the left ventricle (3 cases) and inserted distally into the descending aorta (232 cases), the femoral artery (127 cases), or the abdominal aorta (7 cases). Shunt flows were recorded in 91 cases and varied from 1100 ml to 4900 ml/min, (mean 2526 ml/min). Distal pressure during shunting was measured in 62 patients. It varied from 15 to 120 mm Hg (mean 64.5 mm Hg). The aortic cross-clamp time varied from 8 to 124 minutes (mean 30 minutes). RESULTS: The hospital death rate was 12% overall and 9.9% (35/351) if ruptured aneurysms are excluded. Among 359 operating room survivors, neither immediate nor delayed ischemic spinal cord deficit occurred. Transient renal dysfunction occurred in nine patients (2.4%) and kidney failure in one (0.2%). Five deaths (1.3%) were shunt related. CONCLUSION: Distal perfusion with the 9 mm Gott shunt has proven to be an effective method to preserve spinal cord function. The limited extent of aorta resected and the brief aortic cross-clamp time may also be interactive factors of protection.

Adolescent↗
PubMed1994

[Predictive factors of survival after mitral valvuloplasty].

Survival and freedom from reoperation following mitral valvuloplasty (MV) was evaluated in 54 patients (pts) between October 1973 and December 1992. Ages of 35 men and 19 women averaged 49 years (+/- sd:18 yrs). Preoperative NYHA class was II or III in 48 patients (89%) and class IV in 6 pts. At surgery, degenerative disease was present in 43 patients (80%), rheumatic in 8 pts (14%) and congenital in 3 pts (6%). Annuloplasty (Carpentier 18, Duran 27, others 3) was performed in 48 pts and was the sole procedure in 6 pts. Six pts underwent valvuloplasty without annuloplasty. Associated procedures were performed in 18 patients (33.3%). Operative mortality was 6% (3 pts). Follow-up ranged from 1 to 164 months with a mean of 39 mo. (+/- 5 mo.). Survival at 5 years was 89 +/- 8% and freedom from reoperation was 85 +/- 9%. NYHA status was significantly improved following mitral valvuloplasty (p < 0.00001). Operative complications and unfavorable post-operative NYHA status were significantly predictive of death (p < 0.05). Prior cardiac surgery at the time of MV and post-operative unfavorable NYHA status were associated with increased incidence of reintervention (p < 0.05). We conclude that improved post-operative NYHA status heralds excellent long term survival and increased freedom from reoperation following mitral valve repair.

Adult↗
PubMed1992

Surgical repair of traumatic tricuspid insufficiency: report of three cases.

Traumatic tricuspid insufficiency (TTI) is a rare lesion but is classically encountered as a "steering-wheel injury" in nonbelted car divers. This lesion is often not diagnosed because of its subtle clinical manifestations at first and the presence of associated injuries in multiple trauma. The majority of patients reported were treated with valve replacement but, more recently, successful repair of the native valve has made the latter the treatment of choice. Three patients were referred to us with a delayed diagnosis of TTI 2, 4, and 8 years after being involved in motor vehicle crashes (MVCs). Surgery was required and consisted of resuspension of the valvular leaflet with autogenous pericardium and ring annuloplasty. Two-dimensional echocardiography confirmed tricupid valve competence and the patients remained symptom free at a mean follow-up of 25 months.

Accidents, Traffic↗
PubMed1992

[Heart-skin syndrome and cardiac myxoma: presentation of a case and clinical experience of 17 years].

Between 1971 and 1988, cardiac myxoma was identified in 13 (0.003%) of 4000 patients who underwent open-heart surgery at the hôpital du Sacré-Coeur in Montreal. One patient with multiple right atrial tumours also had abnormal cutaneous pigmentation compatible with the recently identified syndrome of "Carney's complex." This syndrome has also been associated with endocrine abnormalities such as primary nodular adrenal hyperplasia, with or without Cushing's syndrome. The authors review the literature and compare the findings with their experience in the surgical treatment of cardiac myxomas.

Adult↗
PubMed1989

Surgical treatment of ventricular tachycardia. Regional cryoablation guided by computerized epicardial and endocardial mapping.

Extended cryoablation as a single method of myocardial ablation was used for surgical treatment of 33 patients with ventricular tachycardia associated with coronary artery disease. Surgery was guided by roving-probe mapping in 14 patients and by computerized epicardial and computerized, left ventricular, endocardial, multielectrode mapping in 19 patients. In the latter group, the anatomic correlation between sites of the earliest epicardial activation (EA-EPI) and those of the earliest endocardial activation (EA-ENDO) was found to be consistent in the apical region. In contrast, the EA-ENDO corresponding to the EA-EPI localized in the left anterolateral and posterobasal free-wall regions could be localized either in an underlying area or on the septum. All tachycardias with EA-EPI in anterior and posterior right ventricular regions had their corresponding EA-ENDOs in the interventricular septum. EA-ENDO preceded EA-EPI in 33 of 41 tachycardias studied. The converse was observed in the remaining eight tachycardias. Cryoablation was applied regionally in areas corresponding to EA-ENDO, along with standard aneurysmectomy and coronary artery bypass grafting when indicated. Among the entire group of 33 patients, there were two (6%) operative deaths. Ventricular tachycardias recurred spontaneously in two (6%) patients and remained inducible in four (13%), of whom one (3%) died suddenly. After hospital deaths were taken into account, actuarial survival was 74 +/- 9% (mean +/- SD) at 48 months after operation. Among the 10 patients who had an EA-EPI on the right ventricle and an EA-ENDO on the interventricular septum, deep septal involvement was suspected, and arrhythmic failure occurred in five patients; in contrast, complete surgical success was obtained in all nine patients who did not display this pattern during intraoperative investigation. We conclude that regional cryoablation alone in areas of the earliest left ventricular activation is highly effective for treatment of ventricular tachycardia, except in a subset of patients with specific markers of deep septal involvement, which can be detected by computerized epicardial and endocardial mapping.

Action Potentials↗
PubMed1989

Intrapericardial trauma: surgical experience.

From 1975 to 1987, 19 patients (pts) were operated on for a traumatic lesion of the heart or of the ascending aorta. There were 15 males and four females with a mean age of 42 years. Twelve lesions (Group I) were penetrating and seven (Group II) blunt. Group I: Nine patients were in shock upon admission, including six with cardiac tamponade. Six pts were stabbed, three sustained a gunshot wound, and two were accidental victims of a pneumatic gun. In the last pt, with previous lung surgery and mediastinal shift, a chest tube lacerated the right ventricle; this pt died in the operating room (OR), for a mortality rate of 8.3% (1/12). Associated intrathoracic and intra-abdominal lesions were present, but did not influence the outcome. Group II: All pts were involved in motor vehicle accidents. Five pts were in shock, including two with cardiac tamponade. Three pts required extracorporeal circulation (ECC) for aortic valve replacement, tricuspid valve reconstruction, and replacement of the ascending aorta. In one case, a lacerated right ventricle could be repaired without ECC, but the pt died from low cardiac output. Three pts with a ruptured left ventricle were managed in the OR, and two pts exsanguinated for a mortality rate of 43% (3/7). Associated lesions were present and death was related to ventricular rupture. Intrapericardial lesions are relatively rare in our Canadian experience. High survival can be obtained in penetrating injuries, while blunt injuries are more complex and remain highly lethal. ECC should be available for definitive treatment.

Adult↗
PubMed1988

Surgery of the descending thoracic aorta: spinal cord protection with the Gott shunt.

From July, 1974, to July, 1987, surgical treatment of descending thoracic aortic aneurysms was performed in 173 patients at l'Hôpital du Sacré-Coeur de Montréal. The cause of the aneurysms was arteriosclerosis or medial degeneration in 83 patients, trauma in 50, dissection in 34, and a congenital malformation in 6. A single method of external shunting provided distal perfusion in all patients in the series. A 9-mm Gott aneurysm shunt was placed preferentially between the ascending aorta (67%) and the descending aorta (60%). Alternative sites of proximal cannulation (aortic arch, 9%; proximal descending aorta, 22%; left ventricle, 2%) and distal cannulation (abdominal aorta, 3%; left femoral artery, 37%) were chosen based on the location and the extent of the aortic aneurysm. No systemic heparinization was used. In the last 40 patients, a flowmeter adapted for use with the shunt allowed the recording of shunt flow (mean, 2,475 ml/min; range, 1,100 to 4,000 ml/min). Hospital mortality, including patients with ruptured aneurysms, was 15% (26/173). The mean aortic cross-clamp time was 37 minutes (range, 8 to 105 minutes). Of the 173 patients, 168 survived long enough to allow accurate clinical evaluation of the function of the spinal cord: no paraplegia or other spinal cord ischemic injury occurred. To date, our clinical experience has demonstrated the effectiveness of the 9-mm Gott shunt in preserving the functional integrity of the spinal cord during cross-clamping of the thoracic aorta.

Adult↗
PubMed1987

Penetrating chest trauma: a 20-year experience.

From 1965 to 1985, 76 patients were admitted to Sacré-Coeur Hospital, Montreal, with a diagnosis of penetrating chest trauma (PCT). The majority were under the age of 30 years and almost two thirds suffered gunshot wounds. Sixty-seven (88.1%) sustained a lateral or thoracic (T) injury and in nine (11.8%) the lesion was central or mediastinal (M). In the first group (T), 53.7% were treated surgically with thoracotomy, laparotomy, and chest tube (CT) insertion or both; 46.2% were managed conservatively. In the second group (M) the pericardium or the heart was involved, eight patients (88.8%) were managed surgically without the use of extracorporeal circulation and one patient was observed only. Eight (11.9%) died in the thoracic group; all survived in the mediastinal group, for an overall mortality of 10.5%. Shock was associated with increased morbidity and mortality in the thoracic group (T) and infection was the most frequent complication for the entire group of patients under study. There has been a steady increase in the total number of PCT at our hospital during the last two decades suggesting an increase in crime and violence in our urban surroundings.

Adolescent↗
PubMed1987

Surgical treatment of bronchogenic carcinoma: the importance of staging in evaluating late survival.

From 1971 to 1980, 1292 patients with lung cancer were admitted to the Hôpital du Sacré-Coeur de Montréal. This diagnosis represented 0.5% of admissions in 1971 and 1.7% in 1980 (240% increase). Only 4% of patients were nonsmokers. Patients ranged in age from 30 to 93 years with a male to female ratio of 5.5 to 1. Of 414 cervical mediastinoscopies carried out for right and left pulmonary tumours, 120 (29%) showed mediastinal lymph-node metastasis (positive biopsy). For 35 left-sided lesions, both cervical and left parasternal mediastinoscopies produced 13 (37%) positive biopsies. For 45 left upper lobe and left hilum tumours, left parasternal mediastinoscopy alone yielded 18 (40%) positive biopsies. Only 297 (23%) of the 1292 patients were considered to have operable lesions and they underwent thoracotomy - 164 (55%) lobectomies, 104 (35%) pneumonectomies, 2 (1%) segmentectomies and 27 (9%) exploratory thoracotomies. The most common postoperative complication was respiratory failure - in 27 cases (9%); there were 12 (4%) bronchopleural fistulas. The operative death rate was 5% - 1.8% for lobectomy, 7.4% for exploratory thoracotomy and 9.6% for pneumonectomy. Causes of death were respiratory failure (60% of the deaths), hemorrhage (13%), cardiac events (13%) and bronchopleural fistula (13%). The overall 5-year survival was 9.2%. For the 297 patients operated on, the survival at 5 and 10 years was 55% and 36% for stage I disease, 30% and 20% for stage II disease and 10% and 8% for stage III disease, respectively. The mean postoperative follow-up was 41.5 months (range from 3.5 to 14 years).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Acute and chronic traumatic aneurysms of the descending thoracic aorta: a 10-year experience with a single method of aortic shunting.

A 10-year experience in the surgical treatment of traumatic aneurysms of the descending thoracic aorta is reviewed. This series included 40 patients equally divided into two groups. Group I comprised 20 acute ruptures and group II, 20 chronic traumatic aneurysms, all situated at the aortic isthmus. The surgical repair was performed in all patients with a single method of aortic shunting. A Gott aneurysm shunt was used as a temporary external bypass between the ascending and the descending aorta, giving priority to organ protection during aortic cross-clamping. The survival rate was 95% (38/40). The two deaths occurred in the acute group and were related to severe brain trauma present before surgery. The aortic cross-clamping time averaged 43 minutes. Regarding organ protection, no brain damage, no heart failure, no renal dysfunction, and no paraplegia occurred. These results emphasize the safety and the reliability of this shunting procedure.

Adolescent↗
PubMed1984

Staged resection of a life-threatening aneurysm of the descending thoracic aorta and a coexisting aneurysm of the ascending aorta.

The authors report the successful staged resection of a descending thoracic aortic aneurysm and a coexisting ascending aortic aneurysm. The main challenge was to provide optimal proximal aortic decompression to prevent rupture of the ascending aorta during the distal repair. During the period of aortic arch cross-clamping, organ protection was achieved with a Gott shunt inserted proximally in the aortic arch and distally in the left common femoral artery. The importance of this shunting procedure, which has been the basis of our surgical technique in the treatment of all lesions of the descending thoracic aorta, is emphasized.

Aged↗
PubMed1984

Acute dissection of the descending thoracic aorta: repair in an unusual case.

Acute tamponade, although a rare manifestation of a descending thoracic aneurysm, was the dominant clinical feature of a classic type III dissecting aneurysm (arising distal to the left subclavian artery) in a 52-year-old man. High-quality aortography confirmed the diagnosis, ruling out any anomaly of the ascending aorta and the aortic arch. Surgical treatment was carried out 24 hours after the initial episode without cardiopulmonary bypass. Through a left thoracotomy, a Gott shunt was inserted proximally at the apex of the left ventricle and distally in the left femoral artery. Aortic repair with the interposition of a 30-mm woven Dacron prosthesis was successful. Postoperative aortography showed complete restoration of aortic integrity.

Acute Disease↗
PubMed1983

Major mediastinal vascular injuries.

Surgical repair was carried out in 37 patients who had rupture of the thoracic aorta or major branches. The survival rate was 90% (33 of 37). Three deaths occurred in the acute phase, giving a survival rate of 87% (19 of 22). Two patients had severe coexisting brain trauma and the other had profuse intrathoracic hemorrhage before thoracotomy could be carried out. One death occurred in a chronic case (an arch aneurysm) for a survival rate of 94% (14 of 15). A massive air embolism to the brain caused this fatal outcome. There were no instances of left heart failure or renal shutdown in our series. One case of paraplegia occurred because a shunt was inserted erroneously in the distended adventitia from an enormous surrounding hematoma. The distal end of the shunt was not in the aortic lumen so there was no distal perfusion during the period of aortic clamping.

Accidents, Traffic↗