PubMed Health⌕ Search

Biomedical subjects

C M Grondin

Publications and source records attributed to C M Grondin.

At least 19 recordsLinked to original sources
PubMed1989

Cardiac surgery in septuagenarians: is there a difference in mortality and morbidity?

Open heart surgery is being performed with increased frequency in elderly patients. Results vary considerably probably as the profile of the surgical population changes. A comparison was established by means of univariate analysis between two consecutive series of 100 patients undergoing bypass grafting or valvular replacement. Group A patients were 70 years of age or older; group B patients were less than 65 years of age. Various clinical, operative, and postoperative parameters were monitored. A significant difference was found between the two groups. Elderly patients tended to be white, female, with poor left ventricular and renal function, had carotid or peripheral vascular disease, and new onset of symptoms. Fewer patients had single-vessel disease and received internal mammary artery grafts. Operative mortality rate was higher in group A subjects and postoperative neurologic complications were also more frequent in this group. Factors influencing operative mortality were the association between vascular disease, presence of left main coronary artery disease, and urgency of the procedure. The mortality rate was 17.2% in 29 patients with associated vascular disease and 4.8% (3/63) in those without vascular disease (p = 0.048). Operative mortality was 4.1% without left main coronary artery disease, 15% with left main coronary artery disease (p = 0.083), and 4% in 84 patients having elective operations versus 31.2% in patients having 16 emergency procedures (p = 0.001). Short-term follow-up revealed a higher late mortality rate in elderly subjects and suggested an increased incidence of early pulmonary embolus. Nevertheless, elective cardiac surgery may be safely performed in septuagenarians with an expected operative mortality rate under 5%.

Age Factors↗
PubMed1989

Coronary artery bypass grafting with saphenous vein.

Occlusion rate of the saphenous vein is around 12-20% during the 1st year and 2-4% annually for the next 4 or 5 years. Subsequently, this rate doubles, so that at 10 years, approximately 50% of grafts become occluded due to the occurrence of graft atherosclerosis. A similar percentage of patent grafts show atherosclerotic changes at the end of the 1st decade. Sequential vein grafts probably suffer the same fate although late follow-up is lacking. Reoperation is estimated to be 30% at 10 years, as judged by angiographic criteria. The operative risk of reoperation is at least double that of primary operation; symptomatic relief appears to be of shorter duration. Recent technical changes to better preserve medial and endothelial function and to pharmacologically inhibit platelet function may lead to longer duration of the venous conduit.

Coronary Artery Bypass↗
PubMed1987

Factors influencing early and late survival in patients with combined mitral valve replacement and myocardial revascularization and in those with isolated replacement.

During a 5 1/2-year period, 251 patients underwent mitral valve replacement (MVR) at our institution: 76 had combined MVR and coronary artery bypass grafting (CABG), and 175 without major coronary artery disease (CAD) had isolated MVR. In-hospital mortality for MVR + CABG was 13.2% (10/76); it was 8.6% (6/70) when patients with preoperative mechanical support were excluded, 7.9% (5/63) for elective operations, and 8.2% (5/61) for nonischemic mitral disease. Overall, in-hospital mortality for isolated MVR was 6.3% (11/175); it was 4.4% (7/161) excluding patients requiring mechanical support and 3.1% (5/157) for elective operations. Of a host of clinical characteristics in patients with MVR +CABG, few were found to influence in-hospital mortality: age greater than 60 years, degree of incapacitation (New York Heart Association Functional Class IV), previous history of myocardial infarction or congestive heart failure, cardiac enlargement (cardiothoracic index greater than 50%), and ischemic mitral disease (33.3% in-hospital mortality; p less than 0.05). Of the invasive variables, only one influenced in-hospital mortality: wall motion score greater than 10 (31.6% in-hospital mortality; p less than 0.01). Of the operative variables studied, the number of grafts (3 or more: 33.3% in-hospital mortality; p less than 0.05), the need for mechanical support (47.4% in-hospital mortality; p less than 0.0001), and emergency operation (38.5% in-hospital mortality; p less than 0.005) had a significant effect on mortality. The type of mitral lesion, the type of prosthesis, the extent of CAD or the completeness of revascularization, the presence of pulmonary hypertension, and atrial fibrillation appeared to have no influence.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1984

Late tears in leaflets of porcine bioprostheses in adults.

Of 836 patients with a mitral or aortic bioprosthesis who were followed over an 8-year period, 32 required reoperation for prosthetic dysfunction. Of the 26 prostheses removed at operation, 18 (12 mitral and 6 aortic prostheses) showed tears in the valve leaflets. In 7 of the 12 patients with rupture of "mitral" leaflets and in 1 of the 6 patients with torn "aortic" leaflets, the onset of symptoms was sudden, requiring urgent reoperation. Two of the 18 patients died early after reoperation; both had progressive disability and underwent elective operation. In 5 of the 7 patients with torn leaflets in a mitral prosthesis who had acute onset of symptoms, a single tear was found and no gross evidence of calcification was detected. Macroscopic calcification was found in only 8 of the 18 (44.4%) prostheses with torn leaflets (mitral and aortic). Microscopic examination revealed calcific deposits in 9 of the 12 mitral and in all of the aortic bioprostheses. Of the 54 leaflets examined, 29 had tears: 10 were type I; 6, type II; 7, type III; and 6, type IV. Tears in porcine valve leaflets are not an uncommon cause of dysfunction. These tears often lead to acute hemodynamic changes, particularly in the mitral position, and usually require emergency reoperation. They may occur in prostheses that appear grossly normal.

Adult↗
PubMed1984

Reoperation in patients with patent atherosclerotic coronary vein grafts. A different approach to a different disease.

Atherosclerotic changes are often noted in vein grafts at angiography 8 to 10 years after coronary artery grafting. Reoperation in these patients is hazardous, as manipulation of the grafts may loosen atheromatous debris and cause coronary embolization and myocardial infarction. A technique is described to avoid embolization of atheromatous material during reoperation in patients with patent atherosclerotic coronary vein grafts. This technique was carried out in six patients and compared to the standard technique of reoperation in similar patients. The incidence of complicated perioperative myocardial infarction (0/6 versus 5/12) and perioperative death (zero versus three) was lower when our new technique was used. This approach consists of minimal dissection for access to the right atrium and ascending aorta for cannulation, prompt ligation of all patent grafts at the start of cardiopulmonary bypass, cardioplegic infusion through the ascending aorta and subsequently also through newly inserted grafts using larger infusions until myocardial temperatures reach less than or equal to 15 degrees C, and single aortic clamping for distal and proximal anastomoses.

Aged↗
PubMed1984

Comparison of late changes in internal mammary artery and saphenous vein grafts in two consecutive series of patients 10 years after operation.

Postoperative angiographic studies were carried out at 1 month, 1 year, and 10 years in two groups of patients: 238 patients with saphenous vein (SV) grafts and 40 patients with internal mammary artery (IMA) grafts. Cumulative patency was better in IMA grafts, both at 1 year (88.5% vs 76.4%) and at 10 years (84.1% vs 52.8%). Atheromatous changes in patent grafts at 10 years were frequent in SV grafts (29/66 or 43.9%) and uncommon in IMA grafts (1/19 or 5.2%; p less than .02). Attrition rate (11.8%) during the first year in IMA grafts (representing our initial experience with IMA grafts) was comparable to that of SV grafts (15.2%) in a group of patients operated on after 2 years of experience. Therefore, early attrition rate may be related to both experience and type of conduit. Later, at 10 years, the conduit itself appears to be the dominant factor. Furthermore, patients who received IMA grafts had a better survival rate at 10 years (84.3% vs 70%) than those who underwent SV bypass grafting.

Arteriosclerosis↗
PubMed1983

Influence of partial sympathetic denervation on the results of myocardial revascularization in variant angina.

Poor results of the aortocoronary bypass graft operation in the treatment of variant angina have been ascribed to recurrent vasospastic activity due to autonomic imbalance. Cardiac sympathetic denervation (plexectomy) may represent a rational approach in the prevention of vasospasm. To test the value of plexectomy in the treatment of variant angina, 31 patients were studied, 17 of whom (Group 1) underwent conventional coronary artery grafting whereas the remaining 14 (Group 2) underwent cardiac sympathetic denervation also. The 2 groups were similar with respect to age (54 +/- 8 versus 50 +/- 7 years), sex distribution (male/female ratio 12/5 versus 9/5), prevalence of coexisting effort angina (10 versus 12 patients), previous myocardial infarction (7 versus 4 patients), and duration of variant angina (3.3 +/- 5.4 versus 2.4 +/- 2.7 months). The left ventricular ejection fraction was comparable in both groups (60 +/- 11 versus 60 +/- 4%) as were left ventricular end-diastolic pressure (15 +/- 4 versus 13 +/- 5 mm Hg) and extent of coronary artery disease (65 versus 71% prevalence of multivessel disease). The average duration of follow-up was 23 +/- 15 months in Group 1 and 22 +/- 18 months in Group 2 (p = not significant [NS]). There were no operative deaths. Four patients, 2 in each group, had a perioperative myocardial infarction. Seven patients in Group 1 and 1 patient in Group 2 had recurrent variant angina. There was sudden death and 2 infarcts in Group 1. Actuarial curves showed the cumulative probability of recurrent variant angina to be significantly lower (p less than 0.05 and p less than 0.001 at 6 and 10 months, respectively) in Group 2. This study suggests that cardiac sympathetic denervation may prevent recurrent vasospastic activity in variant angina.

Adult↗
PubMed1983

Atherosclerosis and late closure of aortocoronary saphenous vein grafts: sequential angiographic studies at 2 weeks, 1 year, 5 to 7 years, and 10 to 12 years after surgery.

Sequential control angiographic examinations were performed at 2 weeks, 1 year, 5 to 7 years, and 10 to 12 years after aortocoronary saphenous vein bypass surgery in 82 unselected patients. Graft modifications consisting of wall irregularities and obstructive lesions of various severity and shapes that were found to develop after the first year were attributed to atherosclerosis. The incidence of these late changes increased from 16% during the interval between 1 year and 5 to 7 years to 36.4% during the subsequent interval between 7 and 12 years (p less than .01). These changes were not influenced by the severity of early diffuse or localized intimal hyperplasia. They were not related to classical risk factors except for low-density lipoprotein and low-density beta-lipoprotein cholesterol. Graft closure increased 2.5-fold from the interval between 1 year and 5 to 7 years to the following period between 7 and 12 years, 10.2% to 26.1% (p less than .02); thus the mean yearly attrition rate augmented from 2% to 5.3%. Late graft closure may result from early localized stenosis most likely related to improper surgical techniques, but the most frequent cause appears to be atherosclerosis. Graft patency at 10 to 12 years is 63.3%.

Adult↗
PubMed1982

Myocardial protection through cold cardioplegia with potassium or diltiazem. Experimental evidence that diltiazem provides better protection even when coronary flow is impaired by a critical stenosis.

Intermittent aortic root infusion of a cold solution containing either potassium chloride (KCl) or diltiazem was performed in 32 dogs during a 2-hour aortic clamping. Half of the dogs in each group had a critical stenosis created on the circumflex artery before cardiopulmonary bypass. Global left ventricular (LV) function was determined 1 hour after bypass by means of LV pressure, peak dP/dt, LV end-diastolic pressure, cardiac and stroke work indexes. Regional function was assessed through microcrystals in the areas of the circumflex and left anterior descending coronary arteries. LV pressure decreased in all dogs, but more so with the KCl solution (p = 0.02). The stenosis had no specific effect on LV pressure, but affected peak positive dP/dt (p = 0.007) and LV end-diastolic pressure (p less than 0.0001). Cardiac and stroke work indexes decreased more in the KCl group than in the diltiazem group (p less than 0.002) with or without stenosis. Both positive and negative dP/dt were affected by the type of solution (a greater decrease with KCl), but the narrowing affected only the positive dP/dt. Regional LV function remained unchanged in the absence of a narrowing and was depressed equally in dogs with a narrowing whether they received KCl or diltiazem. Overall LV function appeared to be better preserved with diltiazem, with or without impairment of circumflex flow.

Animals↗
PubMed1982

Changes in grafts and coronary arteries after saphenous vein aortocoronary bypass surgery: results at repeat angiography.

We studied the patency of saphenous vein aortocoronary bypass grafts in nonconsecutive and consecutive subgroups of our first 600 patients. The patency rates were 87-93% within 1 month and 74-85% approximately 1 year after surgery. The attrition rate of grafts averaged 2.2% per year between 1 and 6 years. Early occlusion was due to thrombosis; occlusion at 1 year was caused by fibrous intimal proliferation of grafts, which also led to variable reduction in caliber and to significant (greater than 50%) segmental stenoses in 5-15% of patent grafts. The most important determinant of graft patency at 1 year was the runoff capacity of the recipient arteries, followed by the quality of the surgical techniques. Late occlusion was related to atherosclerosis that became manifest only after at least 2 years. Coronary atherosclerosis progressed in more than 50% of proximal segments of grafted arteries during the first year, but little additional deterioration occurred between 1 and 6 years. During the first year, only 10% of preexisting stenoses in nongrafted arteries showed progression of disease; progression in these vessels increased to 46% at 6 years and was no longer different, for preexisting lesions greater than 50%, from that of grafted arteries. A close correlation was observed between changes in grafts and in coronary arteries and long-term survival or relief of angina. Ninety-four percent of patients with all grafts patent and 98% with an optimal correction were alive at 6 years compared with 70% of patients without patent grafts or surgical correction. Changes in grafts or coronary arteries were observed in two-thirds of patients in whom functional deterioration occurred between 1 and 6 years, compared with 18% in whom improvement persisted after surgery.

Angiography↗