Biomedical subjects

N C Poirier

Publications and source records attributed to N C Poirier.

10 recordsLinked to original sources

PubMed2000

A novel repair for patients with atrioventricular septal defect requiring reoperation for left atrioventricular valve regurgitation.

OBJECTIVE: Left atrioventricular valve regurgitation (LAVVR) is the most frequent indication for reoperation following atrioventricular septal defect (AVSD) repair. We estimate from our experience that within 10 years of initial repair, 14% of patients undergoing repair of atrioventricular septal defect (AVSD) require reoperation for this complication. We have developed a novel leaflet augmentation technique for LAVVR which may avoid failure of conventional repair and/or the need for valve replacement. METHOD: The novel technique consists of insertion of a glutaraldehyde-treated autologous pericardial patch to augment the bridging leaflets of the atrioventricular valve. We describe the outcome of eight patients in whom this technique was used and compared them to 68 other patients with AVSD undergoing reoperation for LAVVR by either conventional repair (n=54) or valve replacement (n=14). RESULTS: There were no early deaths or major complications following patch repair. The mean follow-up is 2.3 years (range 1-8.5 years) during which there were no late deaths. Two patients underwent reintervention at 3.5 and 5 years after patch repair for LAVVR and were successfully rerepaired. Mild residual LAVVR was seen at last echocardiography in six patients and mild to moderate in two. These results compare favorably with the 68 patients who underwent conventional surgery. The 3-year freedom from reoperation was 86% for both repair groups. Dysplastic valve tissue appears to be a major risk factor for failure of conventional repair or for valve replacement. Failure of conventional valve repair led to valve replacement in six of seven patients. CONCLUSIONS: For patients with late LAVVR after AVSD repair, pericardial leaflet augmentation is durable and may avoid failure of conventional repair or valve replacement in patients with dysplastic valves.

Adolescent↗

PubMed2000

Modified Norwood procedure with a high-flow cardiopulmonary bypass strategy results in low mortality without late arch obstruction.

OBJECTIVE: The results of our modification of the stage I Norwood procedure, in which we use only autologous tissue to reconstruct the aortic arch, were reviewed. A high-flow, low-pressure cardiopulmonary bypass protocol (with phenoxybenzamine), before and after a period of deep hypothermic circulatory arrest, was used. METHODS: Between 1993 and 1999, 59 patients, aged 1 to 353 days (median 4 days) and weighing 1.7 to 6.8 kg (median 3.2 kg), underwent a modified Norwood procedure. The ascending aortic diameter ranged from 1.5 to 8 mm (median 3 mm). The modified Blalock-Taussig shunt was 3 mm in 21 patients (36%) and 3.5 mm or larger in 38 patients (64%). RESULTS: Deep hypothermic circulatory arrest and cardiopulmonary bypass times ranged from 15 to 64 minutes (median 37 minutes) and 44 to 144 minutes (median 88 minutes), respectively. Early postoperative survival was 83%. By univariate analysis, early mortality was associated with an ascending aortic diameter of 2.5 mm or less (P =.01). Weight, circulatory arrest and bypass times, diagnosis (hypoplastic left heart syndrome vs variant), shunt size, and date of the procedure did not affect survival. For a median follow-up period of 37 months (range 4-63 months), 42 (61%) patients underwent bidirectional cavopulmonary shunts, 10 (17%) had Fontan operations, and 1 patient underwent transplantation after a bidirectional cavopulmonary shunt. Eight patients subsequently died, for a 1-year actuarial survival of 72% (95% confidence interval: 60%-84%). Neoaortic arch obstruction was corrected in 3 patients (5%). CONCLUSIONS: At intermediate-term follow-up, our modification of the Norwood procedure together with our perioperative strategies has resulted in acceptable outcomes with a low incidence of neoaortic arch obstruction. Patients with a small ascending aortic diameter have emerged as a high-risk group, but a recent technical modification may improve the outlook for these patients.

Aorta, Thoracic↗

PubMed1999

Surgical treatment of aortic arch hypoplasia in infants and children with biventricular hearts.

BACKGROUND: Results of aortic arch reconstruction in the setting of biventricular physiology are well documented in the adult population, however, in children, surgical outcome of this subgroup of patients is less clear. METHODS: We studied the clinical outcomes of 37 children aged 8 days to 15 years (median 26 months), who underwent aortic arch reconstruction for arch hypoplasia from 1982 to 1997. The children were divided into three groups: Group 1 (20 patients) had isolated aortic arch lesions, Group 2 (13 patients) had associated intra-cardiac pathology yet conserving a biventricular physiology, Group 3 (4 patients) had Williams Syndrome. Previous interventions for coarctation had been performed in 30 patients (81%). Arch repair consisted of a patch aortoplasty in the majority of patients (35 of 37 children). RESULTS: Operative mortality occurred in 5 children, 4 in Group 2 (31%), 1 in Group 3 (25%) and none in Group 1. Permanent neurological complications occurred in 2 children (5 %). During the follow-up, which ranged from 1 month to 8 years, balloon angioplasty for arch obstruction was required in 1 child. There was one late death, associated with a subsequent intra-cardiac repair. CONCLUSIONS: Aortic arch surgery in children with isolated arch hypoplasia, is associated with excellent early and late survival in addition to a low reintervention rate. Alternative perfusion and operative strategies must be implemented in infants with associated intra-cardiac anomalies to improve results.

Adolescent↗

PubMed1999

Quantitative angiographic assessment of coronary anastomoses performed without cardiopulmonary bypass.

BACKGROUND: The quality of the anastomosis performed during coronary artery bypass grafting without cardiopulmonary bypass is a current concern, and myocardial wall restraining devices have been designed to optimize results. A quantitative angiographic analysis was performed to assess coronary anastomoses performed on beating hearts. METHODS: We studied 34 patients who underwent coronary artery bypass grafting without cardiopulmonary bypass between February 1996 and April 1997. The left internal thoracic artery was anastomosed to the left anterior descending coronary artery in all patients. Coronary angiograms were performed 4 +/- 2 days after the operation. The diameter of the anastomoses was quantified by computer-assisted analysis of grafts and native coronary arteries at the toe and heel of the anastomosis. RESULTS: Five of the patients who underwent coronary artery bypass without a stabilizer (n = 20) had stenoses of the internal thoracic artery grafted to the left anterior descending coronary artery of more than 50% at the level of the anastomosis proper, 3 had stenoses at the heel of the coronary anastomosis, and 5 had stenoses at the toe. One of the patients in whom a stabilizer was used (n = 14) had a stenosis of more than 50% at the anastomosis, and 1 had stenosis at the heel. Eight patients in whom the anastomoses were performed without stabilization (8/20, 40%) had stenoses of more than 50%, whereas there was only 1 stenosis of more than 50% of coronary luminal diameter among the patients in whom the operation was performed with a stabilizer (P =.02). CONCLUSION: The quantitative angiographic evaluation suggests that left internal thoracic artery graft to left anterior descending coronary artery anastomoses have a lesser degree of intraluminal stenosis when performed with the use of a myocardial wall stabilizer.

Aged↗

PubMed1998

Transesophageal echocardiographic evaluation of perioperative coronary sinus trauma.

Retrograde cardioplegia is relatively safe, with a rate of coronary sinus rupture of 0.6%. With the advent of perioperative transesophageal echocardiography, it is now possible to detect and evaluate the extent of damage consequent to the use of retrograde cardioplegia and better formulate an intraoperative course of action. The evolution of these lesions can also be monitored by transesophageal echocardiography during the postoperative period.

Aged↗

PubMed1997

Cricopharyngeal myotomy for neurogenic oropharyngeal dysphagia.

BACKGROUND: Forty patients (18 women, 22 men) with incapacitating oropharyngeal dysphagia of neurologic origin underwent cricopharyngeal myotomy. The subjective and objective response to myotomy was analyzed retrospectively with a mean postoperative follow-up of 48 months (range 1 to 255 months). RESULTS: Radiologic evidence of functional obstruction caused by incoordination and incomplete relaxation of the upper esophageal sphincter was significantly reduced. Manometric recordings of resting and closing pressures of the upper esophageal sphincter were also significantly altered by the myotomy. Resting pressures decreased from 65 to 18 mm Hg and closing pressures dropped from 69 to 22 mm Hg. The relaxation time and poor coordination at the level of the upper esophageal sphincter, observed in the preoperative period, persisted after the operation. Radionuclide emptying studies in which a single liquid bolus was used showed persistent hypopharyngeal stasis with a 20% retention of radioactive material at 120 seconds. Subjectively, 33 patients initially had frequent aspiration episodes. Twenty became free of symptoms after myotomy (p < 0.01) and in six others the symptoms were improved. Overall, seven patients claimed to be free of symptoms of dysphagia and no longer had pharyngo-oral or pharyngonasal regurgitations and aspirations after their operation. Twenty-three other patients had improvement in symptoms. Ten patients reported no change in symptoms. All of them either were unable to swallow voluntarily or had dysarthria when assessed before the operation. One retropharyngeal hematoma is the only postoperative complication recorded. The operative mortality was 2.5% (1/40). CONCLUSIONS: Cricopharyngeal myotomy palliates neurogenic oropharyngeal dysphagia in patients with intact oral-phase deglutition.

Adult↗

PubMed1996

Technique for the repair of diaphragmatic eventration.

In contrast to the large thoracotomy incisions required by standard surgical techniques for repair of diaphragmatic eventration, the procedure we developed can be performed by video-assisted thoracoscopy, thus offering patients the advantages of a minimally invasive operation. Using two superposed series of transverse back-and-forth continuous sutures, the diaphragm is invaginated, then stretched. The first suture line holds the diaphragm down and maintains the excess within the abdomen; the second suture line places the desired tension on the diaphragmatic dome. Successful repair of 3 cases by this technique is described.

Adult↗

PubMed1996

[Popliteal aneurysm: surgical treatment is mandatory before complications occur].

Between 1972 and 1995, surgical repair was undertaken for 94 popliteal aneurysms diagnosed in 71 patients (69 men and 2 women) with a mean age of 66 years. Ninety-one femoropopliteal bypasses, 2 lumbar sympathectomies and one primary amputation were performed. Postoperative results of 28 elective bypasses performed for asymptomatic aneurysms (AA) were compared with 63 revascularisations needed for symptomatic aneurysms (SA) secondary to thrombosis (31%), embolization (30%), venous or nerve compression (13%), or rupture (2.1%). Occlusion of at least one tibial vessel was documented angiographically in 40% of the asymptomatic aneurysms and in 80% of the symptomatic aneurysms. No significant difference was observed between 5-year graft-patency of asymptomatic aneurysms (64%, mean followup 30 months +/- 37.2) and symptomatic aneurysms (50%, mean followup 39 months +/- 40.9). Furthermore, 5-year graft patency was not influenced by the number of patent tibial vessels in either of these populations. No statistically significant difference between these two groups was observed with respect to morbidity (AA: 10.7%, SA: 19%), or early reintervention (AA: 7.1%, SA: 9.5%). However, 12 secondary amputations were needed, all of which were performed after repair of a symptomatic aneurysm (19%, p < 0.05). No postoperative mortality was observed after an elective bypass while 3 patients (4.8%) with symptomatic aneurysms died after an emergency surgery. Ischemic symptoms persisted in 56% of patients who were initially symptomatic. Surgical correction should therefore be performed once the diagnosis of a popliteal aneurysm has been established in order to prevent amputation and late sequelae.

Adult↗

PubMed1994

Antireflux operations in patients with scleroderma.

Fourteen patients with scleroderma underwent antireflux operations (10 short Nissen, 2 Collis-Nissen, 1 Collis-Belsey, and 1 vagotomy and antrectomy with Roux-en-Y). Esophageal function was assessed preoperatively and postoperatively with a follow-up range of 8 to 181 months (mean, 65 months). Reflux symptoms were relieved in 10 of the 14 patients (p < 0.01), as shown by a decrease in their 24-hour acid exposure of from 15% to 7.5% (p < 0.05). However, the lower esophageal sphincter pressure gradient created by the operations did not increase significantly (3.7 +/- 3.4 mm Hg to 5.5 +/- 3.5 mm Hg). The esophageal acid exposure decreased sufficiently to promote some alleviation of the esophagitis. Radiologic signs of stenosis regressed in 6 of 7 patients. Postoperative endoscopic assessment revealed complete or partial healing of erosions seen preoperatively in 6 of the 7 patients so studied, and healing of all ulcers in 3 patients. Twelve patients continued to have columnar metaplasia. Manometric studies disclosed no significant changes in propulsion and contractility. Distal esophageal resting pressures rose significantly from 6.2 to 9.4 mm Hg (p < 0.05 mm Hg), suggestive of stasis. Radionuclide transit studies, however, showed no significant decrease in the esophageal emptying capacity after operation. It is concluded that conventional antireflux operations in patients with scleroderma can palliate reflux damage without jeopardizing esophageal function.

Adult↗

PubMed1994

Endoscopic removal of a right lower lobe bronchial lipoma in a high-risk patient: a case report.

Endobronchial lipomas are rare benign tumours that cause bronchial obstruction, leading to extensive distal parenchymal damage. This report describes the endoscopic removal of a right main bronchus lipoma with a rigid endoscope and snare technique in a high-risk patient. The patient was successfully treated without complication. Endoscopic reaction is the preferred therapeutic approach for this subgroup of patients.

Aged↗