[Coronary aneurysm, it exists !] / L'anévrisme coronarien, ça existe !

Coronary aneurysm has an incidence of 1,1 to 4,9 % in patients undergoing a coronary angiography. Many etiologies may be accused, atherosclerosis is associated in up to 50 % of cases. We report the case of a 76-year-old patient with a large coronary aneurysm.

L'anévrisme coronarien a une incidence de 1,1 à 4,9 % chez les patients bénéficiant d'une coronarographie. De nombreuses étiologies peuvent être incriminées, l'athérosclérose y est associée dans 50 % des cas. Nous rapportons ici le cas d'un patient de 76 ans présentant un volumineux anévrisme coronarien.

Case-matched comparison of early and long-term outcomes of everted cervical vein and saphenous vein carotid patch angioplasty.

OBJECTIVES: To compare outcomes after carotid endarterectomy (CEA) with saphenous vein patch closure (SV), with cervical vein (external jugular and common facial) patch closure (CV). DESIGN: A total of 322 cases of CEA was achieved consecutively by using venous patch angioplasty. Propensity scores were calculated followed by a one-to-one basis case-matching. MATERIALS: This resulted into 90 SV and 90 CV matched cases. METHODS: The primary endpoint was the incidence of ipsilateral stroke and transient ischaemic attack at any time during follow-up. RESULTS: Ten-year freedom from stroke was 94.1% ± 3.5% for the SV group and 90.5% ± 4.2% for the CV group (log rank P = 0.230). Ten-year freedom from ipsilateral neurological events (stroke and transient ischaemic attack) was 93.5% ± 3.3% for SV group and 92.4% ± 3.0% for the CV group (log rank P = 0.403). Ten-year freedom from ≥75% stenosis/occlusion was 93.1 ± 4.8% for the SV group and 89.9 ± 6.0% for the CV group (log rank P = 0.481). CONCLUSIONS: CV is a good alternative to SV patching, particularly when the SV needs to be preserved for further use or is unsuitable.

Flow-mediated vasodilation during pacing of the free epigastric artery bypass graft early and late postoperatively.

OBJECTIVES: The free epigastric artery bypass graft is proposed as an alternative conduit to the saphenous vein graft, known for its high rate of attrition. The aim of our study was to assess its endothelial function in vivo. BACKGROUND: The endothelium of arterial bypass grafts plays a role in both the performance and the patency of such grafts. METHODS: We studied 73 epigastric grafts early (mean +/- SD 10 +/- 3 days) and 36 late (12 +/- 5 months) after coronary bypass surgery with quantitative angiography at rest, after 2 min of atrial pacing (130 beats/min) and after injection of isosorbide dinitrate (1 to 2 mg) into the graft. RESULTS: At rest, mean epigastric graft diameter was lower in the late than in the early postoperative period (2.26 +/- 0.39 vs. 2.61 +/- 0.49 mm, p < 0.001). Early after operation, epigastric grafts with a small or an intermediate runoff, but not those with a large runoff, were capable of vasodilation with nitrates (+0.09 +/- 0.10 mm). Late after operation, vasodilation after administration of isosorbide dinitrate was similar in epigastric grafts with a large runoff and in those with a small or intermediate runoff (+ 0.23 +/- 0.09 vs. +0.23 +/- 0.18 mm). Significant vasodilation during pacing was observed late (+4 +/- 9%, p < 0.01) but not early postoperatively, except in a subset of patients with grafts capable of vasodilation after nitrates. A correlation between the response to nitrates and the response during pacing was observed early (r = 0.579, p < 0.001) and late postoperatively (r = 0.530, p = 0.02). CONCLUSIONS: Flow-mediated vasodilation during pacing was observed in most epigastric grafts late, but not early, after operation. This endothelium-dependent dilation was correlated with the importance of the vasodilation observed with nitrates (endothelium-independent), which was related to the importance of the runoff only in the early postoperative period. The ability of epigastric grafts late postoperatively to dynamically adapt their dimensions to an acute increase in demand could contribute to the good functional results of this new alternative arterial graft.

Effective prevention of atrial fibrillation by continuous atrial overdrive pacing after coronary artery bypass surgery.

OBJECTIVES: The present study was aimed to evaluate the efficacy of a specific algorithm with continuous atrial dynamic overdrive pacing to prevent atrial fibrillation (AF) after coronary artery bypass graft (CABG) surgery. BACKGROUND: Atrial fibrillation occurs in 30% to 40% of patients after cardiac surgery with a peak incidence on the second day. It still represents a challenge for postoperative prevention and treatment and may have medical and cost implications. METHODS: Ninety-six consecutive patients undergoing CABG for severe coronary artery disease and in sinus rhythm without antiarrhythmic therapy on the second postoperative day were randomized to have or not 24 h of atrial pacing through temporary epicardial wires using a permanent dynamic overdrive algorithm. Holter ECGs recorded the same day in both groups were analyzed to detect AF occurrence. RESULTS: No difference was observed in baseline data between the two study groups, particularly for age, male gender, history of AF, ventricular function, severity of coronary artery disease, preoperative beta-adrenergic blocking agent therapy or P-wave duration. The incidence of AF was significantly lower (p = 0.036) in the paced group (10%) compared with control subjects (27%). Multivariate analysis showed AF incidence to increase with age (p = 0.051) but not in patients with pacing (p = 0.078). It decreased with a better left ventricular ejection fraction only in conjunction with atrial pacing (p = 0.018). CONCLUSIONS: We conclude that continuous atrial pacing with an algorithm for dynamic overdrive reduces significantly incidence of AF the second day after CABG surgery, particularly in patients with preserved left ventricular function.

Functional evaluation of internal mammary artery bypass grafts in the early and late postoperative periods.

OBJECTIVES: We sought to determine whether internal mammary artery grafts adapt to an increase in myocardial flow demand and whether they restore maximal flow reserve. BACKGROUND: Although mammary grafts are now considered the graft of choice for coronary artery bypass surgery, there is still controversy about whether they can provide adequate flow at periods of peak myocardial demand. METHODS: Of 28 patients with a mammary graft anastomosed to the left anterior descending coronary artery, 15 were studied early (mean [+/- SD] 8 +/- 2 days) and 13 late (19 +/- 15 months) after operation by quantitative angiography and selective intravascular Doppler analysis at baseline, during pacing and after injection of papaverine and isosorbide dinitrate into the graft. Eleven patients with a normal left anterior descending artery served as control subjects. RESULTS: At baseline, mean graft diameter (2.39 +/- 0.41 vs. 2.42 +/- 0.45 mm) and bypass flow (38 +/- 22 vs. 30 +/- 12 ml/min) were similar in the early and late postoperative periods. Significant and similar vasodilation was observed in mammary grafts after administration of papaverine (+6 +/- 5% vs. +9 +/- 6%) and nitrates (+14 +/- 7% vs. +16 +/- 9%) both early and late after bypass surgery. Graft diameter increased during pacing late (+6 +/- 3%, p < 0.05) but not early after operation. Bypass flow increased similarly during pacing in both groups, but maximal flow reserve induced by papaverine was significantly lower in mammary grafts studied early (2.70 +/- 0.62) than those studied late (3.66 +/- 0.81, p < 0.01) and in normal coronary arteries (4.05 +/- 0.96, p < 0.001). CONCLUSIONS: An increase in myocardial blood flow induced by pacing resulted in vasodilation of mammary grafts in the late but not in the early postoperative period. Significant vasodilation of mammary grafts after papaverine and isosorbide dinitrate administration was observed both early and late after operation. However, bypass flow reserve after papaverine injection was significantly lower in the early postoperative period but normalized over time. This finding seems unrelated to the conduit; rather, it appears to be related to the periphery and could be the result of injury to the microvasculature during operation.

Practice variability in the management of subrenal arterial stenoses in seven Belgian hospitals.

This multicentre retrospective study describes the variation of therapeutic options, treatment outcomes and costs for treating subrenal arterial stenoses as observed in daily practice in 1997-99 in seven Belgian hospitals. Data were obtained from clinical record review and from the sickness fund claims database, and included preoperative functional state, presence of acute ischaemia, diabetes and polyvascular disease, state of the lower-leg run-off arteries, anatomical site and type of lesion, type of treatment, result at 30 days and up to 4 years. A total of 442 episodes were studied, but most analyses dealt with a subgroup of 240 lesions in the common iliac up to the superficial femoral artery. The proportion of surgical treatments (as compared to an endovascular or mixed approach) varied from 15% to 81% between the hospitals. In univariate patency analysis, relapse or failure rates at 4 years ranged from 5% for the common iliac artery to 35% for the superficial femoral artery. Polyvascular disease, a poor run-off, multiple stenoses and chronic occlusion were significant risk factors; age and diabetes were not. In the multivariate (stratified Cox regression) analysis, only a location in the superficial femoral artery and a poor preoperative clinical stage were significant risk factors, but type of therapeutic approach was not. The total average cost of treatment was 5,300 Euros, of which 15% was contributed by the patient. Surgery was associated with longer stays (median at 12 days) than endovascular treatments (median 2 days), and was 1.9 times more expensive. In conclusion, the results of the present study suggest that a multidisciplinary approach, orienting the patient to the most appropriate therapeutic pathway, could increase both the quality and the cost-effectiveness of the care.

Twenty years' experience with the Model 6120 Starr-Edwards valve in the mitral position.

A total of 549 nonconsecutive patients underwent isolated mitral valve replacement with a Starr-Edwards valve prosthesis (Model 6120) at the University of Louvain (Belgium) from 1965 to 1985. Ninety-seven percent of the patients could be traced and only 17 patients were lost to follow-up. Cumulative follow-up totalled 3,130 patient-years. Actuarial and linearized statistical techniques were used to describe the survival and the incidence of valve-related complications (according to stringent criteria). Long-term overall survival rate including early deaths was 79% +/- 0.02% at 5 years, 65% +/- 0.03% at 10 years, and 54% +/- 0.04% at 19 years, with a linearized incidence of late deaths of 3.9% +/- 0.5% per patient-year. The incidence of late valve-related deaths was 1.25% per patient-year. Valve-related complications occurred at the following rates: thromboembolism 3.1% per patient-year, anticoagulant-related hemorrhage 1.08% per patient-year, endocarditis 0.26% per patient-year, reoperation and periprosthetic leak 0.45% per patient-year, and structural failure 0% per patient-year. All valve-related mortality and morbidity were calculated at 4.9% per patient-year and the rate of valve failure (deaths and reoperations) at 1.4% per patient-year. Among 376 survivors, 352 clinical functions could be obtained: 95% of patients belong to Class I or II of the New York Heart Association after operation versus 24% before operation. The study shows the structural durability of the Starr-Edwards mitral valve with a follow-up over 20 years. The Model 6120 valve may be considered a faithful standard.

Use of the inferior epigastric artery for coronary bypass.

Between December 1988 and April 1991, 74 free inferior epigastric arteries were used in 73 patients for coronary artery bypass grafts. In addition, 72 of the patients received a left internal mammary artery for single or sequential grafting to the left anterior descending system and 62 a right internal mammary artery to the circumflex or the right coronary artery. Twenty-seven patients had no saphenous vein available, and two had no suitable internal mammary artery; in an attempt to make a complete arterial revascularization, we chose the inferior epigastric artery as an alternative conduit in 24 young patients and in 10 reoperations; bilateral internal mammary artery dissection was avoided in four patients with impaired lung function and in six patients with selected two-vessel disease to spare one internal mammary artery. The technique for harvesting the inferior epigastric artery is described. Fifty-three inferior epigastric artery grafts were anastomosed to the distal right coronary artery or to its branches, 18 to the distal obtuse marginals of the circumflex artery (three as sequential grafts and one as a natural Y graft), and three to the left anterior descending system. The mean number of distal anastomoses is 3.60 per patient. Seventy proximal anastomoses of the inferior epigastric artery were made to the aorta and four to one internal mammary artery. There were four early deaths and one nonfatal myocardial infarction. Four abdominal wound hematomas needed surgical drainage. Sixty-one patients underwent angiographic study on postoperative day 10:59 of 61 inferior epigastric artery grafts (63 of 65 inferior epigastric artery distal anatomoses) and 111 of 111 internal mammary artery grafts (155 of 156 internal mammary artery distal anastomoses) were patent. Clinical follow-up of all the survivors (100% follow-up) could be obtained with a mean period of 9 months (1 to 28 months). There was no late cardiac death, no infarction, and all the patients were free of angina. Nineteen patients underwent a 6-month postoperative angiographic study. Seventeen of 19 inferior epigastric artery grafts were patent and 16 of 19 were intact; 34 of 34 internal mammary artery grafts (46 of 47 internal mammary artery distal anastomoses) were patent and intact. In conclusion, free inferior epigastric artery grafts can reach the diaphragmatic ischemic areas of the heart. The early patency rate and the clinical results are encouraging but only long-term evolution and evaluation can determine the true efficacy of the inferior epigastric artery graft as a reliable conduit for coronary artery bypass graft operations.

Does flow character of cardiopulmonary bypass make a difference?

The influence of pulsatile bypass flow on the performance of the cardiovascular system, fluids and blood balance, acid-base equilibrium, and splanchnic function was investigated. One hundred patients scheduled for elective coronary artery bypass grafting were randomly divided into a group of standard perfusion (NP) and a group of pulsatile perfusion (PP). At the end of the operation, similar cardiac performance developed in both groups that was higher than before bypass: left ventricular stroke work index after bypass, 56.8 +/- 2.7 gm/beat per square meter in the NP group and 56.7 +/- 2.6 gm/beat per square meter in the PP group (not significant). Further determinations did not differ among the groups. After discontinuation of cardiopulmonary bypass, bypass grafts flow measured using an electromagnetic probe did not differ among the groups. During the postbypass period, mean arterial pressure and systemic vascular resistance were similar (mean arterial pressure 86.8 +/- 1.6 mm Hg in the NP group and 88.5 +/- 1.7 in the PP group; systemic vascular resistance 817 +/- 33 dyne.sec/cm5 in the NP group and 881 +/- 34.5 in the PP group), as were further determinations. However, severe hypotension requiring the administration of vasoconstrictors was observed more frequently in PP group of patients (20 versus 6%; p < 0.05). Fluid balance determined at the second postoperative day was similar among the groups (+1307 +/- 239 ml in the NP group and +1535 +/- 266 ml in the PP group). Blood loss was 1122 +/- 120 ml in the NP group and 1263 +/- 119 ml in the PP group during the first postoperative day (p = 0.407). Urine output during bypass was lower in the PP group (261 +/- 25 versus 341 +/- 26 ml/hr; p = 0.028). The creatinine clearance was 96.4 +/- 10.3 ml/min in the NP group and 92.6 +/- 7.0 ml/min in the PP group (not significant); amylase and lipase clearance did not differ among the groups. Finally, no significant difference was detected in arterial lactic acid determinations and acid-base balance assessment between the groups postoperatively. Thus equivalent cardiovascular hemodynamics, a good control of fluids and blood balance, acid-base equilibrium, and a satisfactory protection of the function of kidneys and pancreas were obtained with both types of perfusion.

Use of the Carpentier-Edwards porcine bioprosthesis: assessment of a patient selection policy.

The Carpentier-Edwards bioprosthesis was implanted in 369 patients (414 valves) between May 1977 and December 1987 (age 67.2 +/- 0.5 years); 242 had aortic valve replacement, 80 had mitral valve replacement, 44 had multiple valve replacement, of which 41 were aortic and mitral valve replacement, 2 had isolated tricuspid valve replacement, and 1 had a pulmonary valve replacement. The selection criteria were the following: shorter life expectancy (253 patients) or contraindications to anticoagulants for organic (113 patients) or psychologic (38 patients) reasons, or both. The early mortality rate was 11.1% (aortic valve replacement, 9.1%; mitral valve replacement, 12.4%; aortic and mitral valve replacement, 23.1%). Total cumulative follow-up was 1456 pt-yr (mean 4.4 years, range 1 to 148 months), and the patient evaluation was 99.5% complete. Late mortality was 4.9%/pt-yr. Five-year survival was 70.4% +/- 2.7% overall, 74.3% +/- 3.2% after aortic valve replacement, 60.9% +/- 6.2% after mitral valve replacement (p < 0.03), and 60.7% +/- 8.1% after aortic and mitral valve replacement. Eight patients were reoperated on for primary tissue failure, and freedom from reoperation for structural valve deterioration was 97.5% +/- 1.2% at 5 years and 95.6% +/- 1.8% at 8 years. Failing aortic bioprostheses were explanted in four patients (0.4%/pt-yr) and mitral bioprostheses in seven (1.6%/pt-yr). No patient whose valve was inserted after the age of 70 had to be reoperated on for structural valve dysfunction. The probability of freedom from thromboembolism after 5 and 8 years of follow-up was 93.1% +/- 1.6% and 92.2% +/- 1.8%, respectively. The prevalence of anticoagulant-related hemorrhage was 0.8%/pt-yr (major 0.6%, minor 0.2%). Anticoagulants had to be maintained in 16.3% of the patients: 5.9% after aortic valve replacement, 35.7% after mitral valve replacement, and 45.8% after aortic and mitral valve replacement, while 80.0% were on a regimen of antiplatelet drug therapy. Prosthetic valve endocarditis happened in five patients (0.3%/pt-yr). Freedom from all valve-related morbidity and mortality, including hospital deaths, was 71.0% +/- 2.7% at 5 years and 58.6% +/- 4.6% at 8 years and was significantly better in the aortic valve replacement group (61.3% +/- 6.6% at 8 years) compared with the mitral valve replacement group (54.4% +/- 7.7% at 8 years; p = 0.04). This study confirms the satisfactory performance of the Carpentier-Edwards valve after aortic valve replacement in elderly patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Revascularization of the circumflex artery with the pedicled right internal thoracic artery: clinical functional and angiographic midterm results.

Retroaortic crossing of the pedicled right internal thoracic artery for revascularization of the circumflex artery used in combination with a pedicled left internal thoracic artery anastomosed to the left anterior descending artery and its branches is an attractive technique to achieve an extensive arterial revascularization of the left ventricle. However, there is a suspicion that pulling the right internal thoracic artery through the transverse sinus could compromise its blood flow capacity and patency. Between January 1990 and July 1994 this technique was applied in 256 patients (202 men, 54 women; average age 62 years, range 31 to 80 years). Sixty-one patients had two-vessel disease and 195 had three-vessel disease. Seventeen patients were undergoing a reoperation. Twenty-two had a left ventricular ejection fraction of 40% or less. Thirty had diabetes. Twenty-eight had morbid obesity. The right internal thoracic artery was directed to the circumflex artery (259 anastomoses) through the transverse sinus and the left internal thoracic artery was anastomosed to the left anterior descending artery and its branches (375 anastomoses) in all patients. The 195 patients with three-vessel disease received additional coronary artery bypass grafts to the right coronary artery (93 saphenous vein grafts, 89 free inferior epigastric artery grafts, 12 pedicled right gastroepiploic artery grafts). In total, the 256 patients received 833 distal anastomoses (average 3.2, maximum 5 per patient) and 634 distal anastomoses were internal thoracic artery anastomoses (average 2.4, maximum 4 per patient). Three patients died early and eight had a nonfatal myocardial infarction. Seven patients needed postoperative intraaortic balloon pump support. Six patients underwent early reoperation because of excessive bleeding. Sternal dehiscence occurred in four patients. One of these four patients died of the complication 10 months after the operation. No patient was lost to follow-up (average 33 months). During follow-up, two sudden deaths and six noncardiac deaths occurred. Two patients had a nonfatal myocardial infarction and 12 had recurrence of angina. There were no late reoperations. One patient underwent a successful percutaneous balloon angioplasty of a native left anterior descending artery. Seventy-four patients, enrolled in prospective angiographic studies, underwent a postoperative recatheterization (average 13.2 months, range 6 to 58 months). Seventy-three of the 74 right internal thoracic artery grafts were patent. In comparison, 74 of 74 of the left internal thoracic artery grafts (106/107 anastomoses) were patent. Maximal stress thallium-201 scintigraphy results, obtained in 25 of those patients, did not reveal ischemia in the area of the circumflex artery.(ABSTRACT TRUNCATED AT 400 WORDS)

Coronary artery bypass grafting with the inferior epigastric artery. Midterm clinical and angiographic results.

Between December 1988 and September 1993, 157 patients (141 men, 16 women, average age 60.2 years, range 37 to 78 years) underwent a complete myocardial revascularization with 157 inferior epigastric artery grafts and 285 internal mammary artery grafts (281 in situ, 4 free grafts). A total of 543 distal arterial anastomoses (average 3.4, range two to five per patient) were constructed, 376 with the internal mammary artery and 167 with the inferior epigastric artery. The inferior epigastric artery grafts were anastomosed to two left anterior descending, 5 diagonal, 34 circumflex, and 126 right coronary arteries. The indications for the use of the inferior epigastric artery were the unavailability of conventional conduits in 56 patients and a favorable anatomy or a young age in 101 selected patients. The clinical follow-up averages 31.8 months (range 6 to 62 months). Four patients died early, and there were three perioperative nonfatal myocardial infarctions. Eight patients required early reoperation for thoracic bleeding (2) or drainage of an abdominal parietal collection (6). There were four late deaths (2 sudden deaths, 2 noncardiac causes) and one nonfatal myocardial infarction. Angina recurred in nine patients, of whom one required reoperation and three underwent successful percutaneous balloon angioplasty of a native coronary artery (2) or an old saphenous vein graft (1). An early recatheterization was obtained before discharge (average 11 days) in 135 patients: 132 of 135 inferior epigastric artery grafts were patent. Seventy-seven patients underwent a second angiographic restudy 6 to 43 months after the operation. Forty-four of the 48 inferior epigastric artery grafts restudied within the first postoperative year (average 8.5 months) were patent, but eight showed a diffuse narrowing. Twenty-eight of the 29 inferior epigastric artery grafts examined angiographically between 13 and 43 months (average 25 months) were open, and among those 29, 25 were widely patent, perfectly matching the receiving coronary artery. Most of the occluded or narrowed inferior epigastric artery grafts were grafted onto coronary arteries with mild stenosis at restudy. Five patients underwent a third angiographic reexamination up to 60 months after the operation (average 39 months). All five inferior epigastric artery grafts were widely patent. The early attrition rate of the inferior epigastric artery, as for any free arterial graft, is probably the result of both the loss of a true pedicle and the need for constructing an additional proximal anastomosis. The fact that the patency rate of the inferior epigastric artery graft seems to remain stable beyond 1 year could suggest a good durability in the future.

Intraoperative hemodynamic assessment of gastroepiploic artery and saphenous vein bypass grafts: a comparative study.

OBJECTIVE: Blood flow characteristics of right gastroepiploic artery and saphenous vein conduits were compared during bypass surgery. METHODS: This study is based on a consecutive series of 97 patients undergoing a bypass graft to the right coronary artery, posterior descending artery, or posterolateral branch using either a pediculated right gastroepiploic artery (n = 52) or a saphenous vein (n = 45) bypass graft. Flows and velocity profiles were measured with an 8-MHz pulsed-wave Doppler ultrasound flowmeter. Thorough flow measurements were made (1) after cessation of cardiopulmonary bypass and (2) before chest closure. RESULTS: At the end of cardiopulmonary bypass, flow in the right gastroepiploic artery (59. 0 +/- 6.7 mL/min) did not differ (P =.08) from flow in the saphenous vein (46.1 +/- 2.7 mL/min). Mean trace velocity was 11.9 +/- 0.7 cm/s in the right gastroepiploic artery and 11.6 +/- 0.8 cm/s in the saphenous vein (P =.80), but peak systolic velocity was 29.4 +/- 1.2 cm/s for the right gastroepiploic artery and 23.1 +/- 1.3 cm/s for the saphenous vein (P <.001). Likewise, before chest closure, flow was 57.1 +/- 4.7 mL/min in the right gastroepiploic artery and 46.5 +/- 4.0 mL/min in the saphenous vein (P =.10), mean velocity was 12. 9 +/- 0.7 and 11.6 +/- 0.8 cm/s, respectively (P = .22), and systolic peak velocity was 30.0 +/- 1.2 and 22.3 +/- 1.2 cm/s, respectively (P < .001). CONCLUSIONS: There were no flow differences between right gastroepiploic artery and saphenous vein grafts implanted into the same coronary bed in comparable groups of patients. Waveform shape of the right gastroepiploic artery grafts was characterized by a wider spectral dispersion resulting in a higher maximal frequency.

Coronary bypass with both internal mammary and inferior epigastric arteries.

A patient having undergone triple coronary artery bypass grafting with the left internal mammary artery and both shorter saphenous veins was reoperated on because of occlusion of the venous grafts. As there was no other vascular substitute available, the right internal mammary artery and both inferior epigastric arteries were used to achieve myocardial revascularization. This case demonstrates that bilateral internal mammary arteries and inferior epigastric arteries can be used safely.

Intraoperative electromagnetic flowmeter measurements in coronary artery bypass grafts.

This study attempts to relate flow findings in internal mammary (IMA) and saphenous vein coronary artery bypass grafts to postoperative outcome. From 262 patients undergoing coronary artery bypass grafting, 601 electromagnetic flow measurements were obtained in IMA and saphenous vein grafts, and free graft flow was measured in 227 IMAs prior to grafting. Retrograde flushing of the IMA with diluted papaverine hydrochloride resulted in a marked increase in IMA free flow (124 +/- 4 mL/min versus 66 +/- 5 mL/min; p < 0.001). However, IMA free flow did not correlate with electromagnetic flow measurements after grafting to the left anterior descending coronary artery. The use of IMAs with free flows lower than 50 mL/min did not affect clinical outcome. Flow measured in saphenous vein grafts (66 +/- 9 mL/min) with an electromagnetic flowmeter was significantly greater (p < 0.001) than that in the IMA grafted on the left anterior descending coronary artery (36 +/- 3 mL/min) under comparable hemodynamic conditions. For the purpose of data analysis, patients were separated into three groups based on increasing incidence of complications: levels 0, 1, and 2. Patients with an uneventful outcome had a mean graft flow at chest closure of 51 +/- 3 mL/min versus 51 +/- 4 mL/min for patients in complication level 1 and 45 +/- 11 mL/min for patients in complication level 2 (p = not significant). Free flow measured in a vasodilated IMA was a poor predictor of flow into a grafted IMA and did not affect clinical outcome. We were unable to validate any flow limit to use of the IMA.(ABSTRACT TRUNCATED AT 250 WORDS)

Mitral valve Carpentier-Edwards bioprosthetic replacement, thromboembolism, and anticoagulants.

Patients undergoing mitral valve replacement (MVR) using a bioprosthesis are frequently placed on long-term anticoagulant treatment, and thereby lose the main advantage conferred by the bioprosthesis. To assess predictive factors of the need for long-term anticoagulant treatment, 100 consecutive patients surviving bioprosthetic MVR between 1977 and 1987 were followed up. The estimated thromboembolism-free survival was 88.9% +/- 3.6% after 6 years of follow-up. Preoperative risk factors for thromboembolism were supraventricular arrhythmia (p = 0.013) and a history of thromboembolism (p = 0.039). Among the preoperative and postoperative factors, only postoperative rhythm significantly influenced (p = 0.007) the thromboembolism-free survival, as determined by Cox regression analysis. Permanent anticoagulant treatment was instituted in 39 patients. Preoperative and peroperative risk factors associated with the need for long-term anticoagulant treatment, as evidenced by Fisher linear discriminant analysis, were supraventricular arrhythmia (p < 0.001), septal myotomy (p = 0.013), and predominant mitral stenosis (p = 0.013). Thus, in those patients with predominant mitral stenosis and supraventricular arrhythmia preoperatively, the subsequent need for permanent postoperative anticoagulant treatment is high, and the implantation of a mechanical valve is therefore recommended, providing there are no strict contraindications to anticoagulant treatment.

Intraoperative assessment of coronary artery bypass grafts using a pulsed Doppler flowmeter.

A pulsed Doppler flowmeter was used in a series of 352 consecutive patients undergoing isolated coronary artery bypass grafting. Doppler flow measurements were available on 909 single terminolateral bypass grafts (327 internal mammary arteries and 582 saphenous veins) and 58 sequential bypass grafts anastomosed to combinations of arteries. Flow (mL/min) categorized as a function of the recipient artery was distributed as follows: left anterior descending coronary artery, 69.9 +/- 2.5; right coronary artery, 68.0 +/- 5.0; diagonals, 61.0 +/- 4.1; obtuse marginals, 55.9 +/- 2.2; and posterior descending coronary artery, 53.3 +/- 3.0 (p < 0.001). Graft outflow obstruction resulting from torsion of the graft pedicle or anastomotic stricture was identified in 7 patients (2%). After graft revision, flow increased from 9 +/- 4 mL/min to 69 +/- 13 mL/min (p = 0.023), and velocity rose from 4.6 +/- 1.1 cm/s to 18.1 +/- 2.4 cm/s (p = 0.009). In conclusion, the system was adequate for operative use and allowed identification and correction of technical errors.

Right internal mammary artery extended with an inferior epigastric artery for circumflex and right coronary bypass.

The right in situ internal mammary artery extended end to end with a free inferior epigastric artery was used through the transverse sinus for sequential grafting to one marginal branch of the circumflex artery and one or both distal branches of the right coronary artery. This procedure was applied in 5 patients with three-vessel disease who received in addition a left in situ internal mammary artery as a sequential graft to the left anterior descending coronary artery and one of its diagonal branches. The postoperative course was uneventful in all cases. A postoperative coronary angiogram obtained on day 10 in 4 patients showed all the grafts and anastomoses patent.

Unusual pitfall of use of retrograde cardioplegia.

The use of retrograde cardioplegia can lead to several complications, mainly related to injuries during the cannulation of the coronary sinus. We herein present a case report of injury to the right coronary artery related to kinking due to the pursestring on the right atrium.

Initial experience with low-potassium cold blood cardioplegia: a clinical comparative study.

This study presents the results of bypass grafting in 96 patients operated on for triple-vessel coronary artery disease between May 1988 and September 1990. In the first 54 patients a cold crystalloid solution was employed, and in the 42 more recent patients cold blood low-potassium cardioplegia was employed. There were no differences in postoperative cardiac index or left ventricular stroke work index. Yet, in patients with impaired prebypass left ventricular stroke work index, postbypass left ventricular performance correlated negatively with duration of aortic cross-clamping in the cold crystalloid group (r = -0.441, p = 0.045). In contrast, no correlation was found in the cold blood low-potassium group (r = 0.125, p = 0.587). The incidence of myocardial infarction, need for inotropic support, and need for intraaortic balloon counterpulsation were similar among the groups. Release of the myocardial isoenzyme creatine kinase-MB from 12 to 30 hours after operation was significantly less in the low-potassium blood cardioplegia group. The use of low-potassium blood cardioplegia resulted in a marked reduction in the operative administration of fluids (1,527 +/- 87 versus 3,511 +/- 148 mL; p less than 0.001). In conclusion, low-potassium cold blood cardioplegia is a simple and effective method of myocardial protection. The fact that left ventricular stroke work index recovery was not dependent on the duration of aortic occlusion and that release of the MB isoenzyme of creatine kinase was reduced in the low-potassium blood cardioplegia group implies better myocardial protection.