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L Noyez

Publications and source records attributed to L Noyez.

At least 37 records · Page 2Linked to original sources
PubMed1994

Initial clinical results of myocardial revascularization with the internal mammary artery for evolving myocardial infarction.

In 25 patients undergoing emergency revascularization for an evolving myocardial infarction, the internal mammary artery (IMA) was used as graft. To bridge the time needed for harvesting the IMA, the left ventricle was totally decompressed by means of the extracorporeal circulation. Cardioplegia was delivered retrogradely, in order to achieve a good distribution in the jeopardized area. One patient died postoperatively, and eight patients showed a postoperative myocardial infarction. These initial results suggest that, with an adapted operative strategy, the IMA can be used as graft even in emergency revascularization.

Aged↗
PubMed1994

Importance of the coronary collateral circulation for the distribution of anterograde and retrograde delivered cardioplegic solution in aortocoronary bypass surgery: a haemodynamic study.

The importance of coronary collateral circulation for homogeneous distribution of anterograde and retrograde delivery of cardioplegia was evaluated in 36 patients undergoing myocardial revascularization. All patients had three-vessel coronary artery disease, with a stenosis of the right coronary artery of at least 80%. The patients were randomized into two groups: group A (n = 19) received anterograde delivered cardioplegic solution and group B (n = 17) received retrograde. Both groups were further subdivided depending on the pathology of the right coronary artery, as evaluated on preoperative coronary angiography. In group A1 (n = 8) and group B1 (n = 7) there was no visualization of collateral circulation from the left to the right coronary artery system, whereas in group A2 (n = 11) and group B2 (n = 10) there was retrograde filling of the right coronary artery by collateral circulation. Right atrial pressure increased significantly (P < 0.05) in group A1 and was elevated in group A2, but not significantly (P = 0.07). By contrast, right arterial pressure decreased in groups B1 and B2. Analysis of the individual differences in the right atrial filling pressure showed a statistical significance between the two subgroups (group B1-1.0(0.5) versus group B2-1.8(1.1), P < 0.05), although the individual decrease of the right ventricular stroke work index was not significant. It is concluded that collateral circulation is important for an adequate distribution of anterogradely delivered cardioplegia and is also beneficial in cases of retrograde delivery.

Adult↗
PubMed1994

Experience and early results of second reoperations for coronary artery disease. Should patent vein grafts be replaced during reoperation?

Reoperation for coronary artery disease has become a routine procedure; however, a second reoperation is exceptional. In this report we describe our experience with 16 patients undergoing a second reoperation for coronary atherosclerosis. The absence of operative mortality is certainly related to the patient selection. The number of patients is still too small to draw major conclusions. Striking, however, is that the first reoperation was usually done for angina because of progression of atherosclerosis in the native coronary system and the second reoperation was done because of graft failure. This experience supports the idea that the replacement of old, even patent, venous grafts and the choice of the best available conduits are of great importance at the first reoperation and may prevent a second reoperation.

Coronary Angiography↗
PubMed1993

Recycling of the internal mammary artery in coronary reoperation.

In 5 patients undergoing a coronary artery reoperation, the internal mammary artery graft was taken down and reused. No special problems were encountered perioperatively or postoperatively. Because the number of grafts and distal anastomoses performed in coronary reoperations is increasing, lack of suitable graft conduits will be a problem in the future. Recycling an internal mammary artery graft may be an option to achieve good revascularization in some coronary reoperations.

Aged↗
PubMed1993

Noninvasive hemodynamic assessment of the internal mammary artery in myocardial revascularization.

Using transthoracic B-mode imaging and Doppler spectrum analysis it was found that the luminal diameter of the internal mammary artery and its hemodynamics were not significantly different among 15 preoperative patients (64 +/- 10 years) who underwent myocardial revascularization using the left internal mammary artery and young and older control groups (25 +/- 3 years and 61 +/- 9 years, respectively). These data indicate that older age does not significantly adversely influence the degree of intimal thickening and compliance in the internal mammary artery. Doppler spectrum analysis of the internal mammary artery in the patients who were operated on revealed conversion from a triphasic systolic waveform preoperatively to a unidirectional combined systolic/diastolic waveform at 1 week and 2 and 6 months postoperatively, characterized by a significant increase in the diastolic blood flow velocity and a significant decrease in the systolic blood flow velocity and the pulsatility and resistance indices. This study indicates that transthoracic B-mode imaging and Doppler spectrum analysis are promising noninvasive techniques in the preoperative assessment of internal mammary artery morphology and physiology. In addition, Doppler spectrum analysis can also be used in the long-term serial assessment of the internal mammary artery conduit after myocardial revascularization.

Adult↗
PubMed1993

Haemodynamic evaluation of retrograde versus anterograde delivery of cardioplegic solution in aortic valve replacement.

A total of 44 patients undergoing isolated aortic valve replacement received either anterograde (20 patients) or retrograde (24 patients), cold St Thomas's Hospital cardioplegia. The patients were similar with respect to age, sex, left ventricular ejection fraction, left ventricular-aortic pressure gradient, cross-clamping time and mean dose of cardioplegia. After surgery, there were no differences in enzyme release, low cardiac output syndrome, rhythm disturbances or clinical outcome between the two groups. Analysis of the postoperative haemodynamic data, however, suggests better preservation of left ventricular contractility with retrograde delivery of cardioplegic solution.

Adult↗
PubMed1993

Sternal closure: comparison of two techniques.

A clinical trial was performed to evaluate sternal closure with the controlled tension osteosynthesis system and closure with twisted stainless steel wires. Some 451 consecutive patients who underwent isolated coronary bypass surgery between January 1991 and December 1991 were subdivided into three groups. Patients in group A (94 patients) and group B (98 patients) were all operated on by one surgeon, to reduce variability before, at the time of and after surgery, which might influence sternal wound healing. To exclude a possible preference of the surgeon in the study, group C was formed, consisting of 259 patients operated on by other hospital surgeons. In groups A and C, sternal closure was performed with the controlled tension osteosynthesis system. In group B, sternal closure was performed with (six) twisted stainless steel wires. Among groups A, B and C, no statistical significant difference could be found between the rate and the type of sternal wound complications. Despite this finding, there were significantly more reoperations, a longer cross-clamp time and more extensive use of the internal mammary artery as a graft in group B. Despite the non-randomization of the study, and the small patient numbers being a limitation, the use of the controlled tension osteosynthesis system in adults did not result in a decrease of early sternal wound complications.

Adult↗
PubMed1993

Experiences with retrograde delivery of cardioplegia in coronary reoperations.

Myocardial protection is the cornerstone of cardiac surgery especially in coronary reoperation, where the most striking problem is perioperative myocardial infarction. Use of retrograde delivery of cardioplegic solution may be preferable in coronary reoperation. Experience is described with retrograde cardioplegia in 48 reoperations for myocardial revascularization, and the advantages and limitations of this technique discussed.

Adult↗
PubMed1993

Retrograde versus antegrade delivery of cardioplegic solution in myocardial revascularization. A clinical trial in patients with three-vessel coronary artery disease who underwent myocardial revascularization with extensive use of the internal mammary artery.

The effects of retrograde and antegrade delivery of cardioplegic solution on myocardial function were evaluated and compared in 60 patients who underwent myocardial revascularization. All patients had three-vessel coronary artery disease, and the revascularization was done with extensive use of the internal mammary artery. Seventy-five percent of the distal anastomoses were performed with the internal mammary artery. Myocardial protection consisted of St. Thomas' Hospital cardioplegic solution, topical slushed ice, and systemic hypothermia (28 degrees C). The patients were randomly separated into two groups: group A (n = 30), who received antegrade cardioplegia, and group B (n = 30), who received retrograde cardioplegia. With the exception of the total dose of cardioplegic solution (p = 0.02), there was no significant difference between the two groups that concerned septal myocardial temperature at the moment of asystole and after infusion of the total dose of cardioplegic solution. Cardiac function was assessed before and after the patient was weaned from cardiopulmonary bypass. In the immediate postoperative period there was a significant increase in right atrial pressure of the patients who underwent antegrade cardioplegia. For the other registered parameters there was no significant difference either in the immediate postoperative period or 6 hours later. Release of creatine kinase MB isoenzyme was the same in the two groups. Clinical outcome in terms of mortality, prevalence of perioperative infarction, prevalence of low cardiac output, and rhythm and conduction disturbances was similar in both groups. Technical problems related to cannulation and decannulation of the coronary sinus were not encountered. Multivariate analysis showed that occlusion of the left anterior descending coronary artery (p = 0.012) is an essential contraindication of antegrade delivery of cardioplegic solution. Analysis of the patients with an occlusion of the left anterior descending coronary artery who underwent antegrade (n = 9) and retrograde (n = 10) cardioplegia showed a significant difference in the total dose of cardioplegic solution (p = 0.02) and septal myocardial temperature at the moment of asystole (p = 0.008) and after infusion of the total dose of cardioplegic solution (p = 0.015). The mean arterial systolic blood pressure in the antegrade group was significantly lower than in the retrograde group (p = 0.003). Preservation of the left ventricular stroke work index was significantly better in the retrograde group (namely, 85% of its initial value versus 71% in the antegrade group, p = 0.0116).(ABSTRACT TRUNCATED AT 400 WORDS)

Bicarbonates↗
PubMed1992

Early results with bilateral internal mammary artery grafting in coronary reoperations.

In recent years, use of the internal mammary artery (IMA) as first graft of choice has been expanded with bilateral and sequential grafts in primary myocardial revascularization. The use of bilateral IMA grafts in reoperation has seldom been reported. The experience and early results with bilateral IMA grafting in 47 patients undergoing coronary reoperation are described. Hospital mortality was 6.3%. Four patients had postoperative signs of low cardiac output, and 4 had a perioperative myocardial infarction. At follow-up (18 +/- 18 months), 2 cardiac-related, late deaths were noted. Thirteen patients (29%) improved 1 New York Heart Association class, and 28 (63%) improved > 1 class. In 1 of 44 surviving patients, operation did not result in a decrease in angina. On the basis of the early results, the bilateral use of the IMA in coronary reoperation appears justified.

Adult↗
PubMed1992

Evaluation of myocardial protection by combination of lidoflazine pretreatment and St. Thomas' Hospital cardioplegia in aorto-coronary bypass grafting.

The concept of pretreatment of the myocardium with a pharmacological agent protecting the cell against ischemic and reperfusion injury is very attractive. Lidoflazine, a calcium overload blocker, predominantly membrane stabilizing, is able to prevent cell damage during ischemic arrest and reperfusion. The purpose of this study was to determine whether the combination of lidoflazine pretreatment and St. Thomas' Hospital cardioplegia can provide, in clinical practice, better myocardial protection in aorto-coronary bypass grafting than St. Thomas' Hospital cardioplegia alone. As indices for myocardial protection, recovery of cardiac function, enzyme release, and clinical outcome were registered. Ninety-three patients undergoing aorto-coronary bypass surgery were studied. These patients were randomized into two groups in a double blind fashion. Patients in group A (n = 48) received lidoflazine 1 mg/kg intravenously over a period of 20 min before initiation of cardiopulmonary bypass. Group B (n = 45) receiving placebo, acted as a control group. Myocardial protection consisted of intermittent infusion of cold 4 degrees C St. Thomas' Hospital cardioplegia, topical slush ice, and systemic hypothermia (28 degrees C rectal). No significant differences between the two groups were noted in terms of recovery of cardiac function, enzyme release, incidence of myocardial infarction, low cardiac output, rhythm, and conduction disturbances. In conclusion, our data suggest that the combination of intravenous pretreatment with lidoflazine and St. Thomas' Hospital cardioplegia did not provide significant additional myocardial protection in the clinical situation.

Aged↗
PubMed1992

Use of internal mammary artery in radiation-induced coronary artery disease.

In 3 patients who had been subjected to mediastinal irradiation for breast cancer, the internal mammary artery was used as a conduit for myocardial revascularization. Intraoperatively, in all patients the internal mammary artery exhibited excellent blood flow and except for mild adhesions between the pericardium and epicardium no unusual technical problems were encountered. Preoperative assessment of the internal mammary artery by angiography is recommended in patients with radiation-induced coronary artery disease who are scheduled to undergo myocardial revascularization with intended use of the internal mammary artery.

Breast Neoplasms↗
PubMed1992

Retrograde coronary sinus cardioplegia in myocardial revascularization: hemodynamic evaluation of the influence on the right-ventricular function.

The problem of the efficacy of right-ventricular protection with retrograde coronary sinus cardioplegia is studied. Sixty patients undergoing myocardial revascularization were prospectively assigned to receive cold St. Thomas' Hospital cardioplegia into the aortic root (30 patients) or retrogradely in the coronary sinus (30 patients). The two groups were similar concerning preoperative and operative data. The hemodynamic recovery postoperatively was good in both groups, the increase of the heart rate, the decrease of the mean aortic pressure and the right-ventricular stroke-work index were not significantly different in the two groups. However, right atrial pressure increased significantly (p less than 0.001) in patients who received cardioplegia anterogradely and decreased, but not significantly, in the retrograde group. The data suggest that the decrease of the right-ventricular stroke-work index in the anterograde group is related to a depressed contractility and in the group with retrograde delivery of cardioplegia to a decreased preload. There were no differences between the groups with respect to clinical outcome. We conclude that retrograde delivery of cardioplegia results in an excellent protection of the right-ventricular function in elective myocardial revascularization.

Adult↗
PubMed1992

Detrimental sequelae on the wall of the internal mammary artery caused by hydrostatic dilation with diluted papaverine solution.

We studied the effect of hydrostatic dilation of the internal mammary artery used for coronary revascularization in 10 patients (aged 45 to 79 years, median 63 years). Diluted papaverine solution was injected in the lumen of distal segments of the internal mammary artery, the musculophrenic artery, or the superior epigastric artery that had been obtained at operation; injection was followed by hydrostatic dilation not exceeding a sheer force of 50 gm. In 12 control patients (aged 42 to 76 years, median 64 years) in whom the internal mammary artery had also been harvested for elective myocardial revascularization, similar arterial segments were wrapped in sponges soaked in papaverine solution of the same dilution. In the nondilated group the median (with interquartile range) number of fenestrations in the internal elastic lamina increased from the elastic (21, 7) to the elastomuscular (41, 11) and muscular segments (89, 12) (elastic-elastomuscular: p = 0.006; elastic-muscular: p = 0.006; elastomuscular-muscular: p = 0.003) (Wilcoxon signed-rank test). In none of the three histologic segments were full-thickness disruptions of the intima and disruptions of the internal elastic lamina seen. Similarly, in the dilated group the number of fenestrations in the internal elastic lamina increased from the elastic (25, 18) to the elastomuscular (43, 9) and muscular (100, 13) segments (p values 0.01, 0.01, and 0.006, respectively). In addition, in 20% of the elastic sections, in 17% of the elastomuscular sections, and in 35% of the muscular sections of the dilated group, disruptions of the intima and internal elastic lamina were seen. Comparison of the number of fenestrations in internal elastic lamina in the three histologic segments between the nondilated and dilated groups revealed a significantly greater value in the muscular segments of the latter group (p = 0.01) (Mann-Whitney U test). We concluded that (1) hydrostatic dilation of the internal mammary, musculophrenic, and superior epigastric arteries may have detrimental effects on the histologic characteristics of the intima and the internal elastic lamina and (2) the number of fenestrations in the internal elastic lamina of these arteries is related to the presence or absence of elastic lamellae in the media.

Aged↗
PubMed1992

Use of internal mammary artery in myocardial revascularization after mediastinal irradiation.

Ten patients with radiation-associated proximal coronary artery disease underwent myocardial revascularization. In seven patients (group A) the internal mammary artery was used and in the other three (group B) only venous conduits were used. Except for mild adhesions between the pericardium and the epicardium, no unusual technical problems were encountered. In all patients in group A the internal mammary artery exhibited excellent flow, and histologic examination in two patients revealed a normal intima and media with only slight fibrosis of the adventitia. In two patients in group B, fibrosis of the internal mammary artery precluded its use, whereas the third patient had contraindications prohibiting use of the internal mammary artery. Long-term follow-up (range 6 to 72 months) revealed that one patient in group A died late of metastatic disease, and of the remainder (nine patients), seven were in New York Heart Association class I and two were in class II. Preoperative assessment of the internal mammary artery by angiography or, alternatively, B-mode imaging with Doppler spectrum analysis is recommended in patients with radiation-induced coronary artery disease who are scheduled to undergo myocardial revascularization with intended use of the internal mammary artery. In our experience, despite previous exposure to irradiation, the internal mammary artery should still be considered as a viable conduit for myocardial revascularization when preoperative assessment shows patency.

Adult↗