PubMed Health⌕ Search

Biomedical subjects

M Buche

Publications and source records attributed to M Buche.

At least 37 records · Page 2Linked to original sources
PubMed1996

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.

Cardiac Catheterization↗
PubMed1996

Myocardial revascularization for severe left ventricular dysfunction. Factors influencing early and late survival.

The results of coronary bypass surgery have been assessed in 102 patients with severe left ventricular dysfunction who had a preoperative left ventricular ejection fraction of < or = 0.35 (mean (s.e.m.) 0.29 (0.01)). Independent risk factors influencing operative mortality were obesity (P = 0.0290) and the need for preoperative intra-aortic balloon counterpulsation (P = 0.0010). Cox regression analysis using as its end-point 'cardiac-related death' demonstrated three variables; the need for preoperative intra-aortic balloon counterpulsation (P < 0.001), advanced age (P = 0.011), and obesity (P = 0.36). In a subset of 43 patients who did not have these risk factors, the 4-year cardiac-related death rate was 95.1 (3.4)%. The operative mortality and long-term survival can be expected to be satisfactory in patients with severe left ventricular dysfunction, provided they have a viable myocardium rather than myocardial fibrosis.

Aged↗
PubMed1996

Current status of the inferior epigastric artery.

The current trend is to use more arterial conduits for myocardial revascularization. The rationale for this trend is that the late patency rate of internal thoracic artery grafts has been shown to be superior to that of saphenous vein grafts. The desire to achieve complete myocardial revascularizations only with arterial conduits has led to consideration of new arteries as coronary artery bypass grafts. Recently, the inferior epigastric artery has been proposed as one of these alternative grafts. It is expected that this new conduit will provide the same advantages as the free internal thoracic artery used in similar circumstances, but this assumption has not been validated yet. This article will review the clinical experience currently gained with the use of the inferior epigastric artery as a coronary artery bypass graft.

Anastomosis, Surgical↗
PubMed1995

Operation for unstable angina pectoris: factors influencing adverse in-hospital outcome.

Coronary artery bypass grafting for the treatment of unstable angina is still associated with increased operative risk and postoperative morbidity. The impact of the extended use of arterial grafts on early results is incompletely defined. In a 7-year period (1986 to 1993), 474 patients (average age, 65 years; range, 34 to 85 years) underwent coronary artery bypass grafting for the treatment of unstable angina. Sixty-eight patients were operated on emergently and 406 urgently. They received an average of 3.0 distal anastomoses (range, 1 to 6). Seventy-nine patients had exclusively venous grafts, 316 had one internal thoracic artery graft, 79 had bilateral internal thoracic artery grafts, and 20 had inferior epigastric artery grafts. Sequential internal thoracic artery grafting was performed in 70 patients. Redo operations were performed in 26 patients. Thirty-four patients (7.2%) experienced a new myocardial infarction. Eighty-nine patients (18.8%) had an intraaortic balloon pump inserted preoperatively, intraoperatively, or postoperatively. Eight patients (1.7%) died intraoperatively and 24 patients (5.1%) died postoperatively. Seventy-seven patients (16.2%) had an adverse outcome, as shown by the need for an intraaortic balloon pump (intraoperatively or postoperatively) or hospital death, or by both. Forty variables were examined by multivariate analysis for their influence on the occurrence of an adverse outcome. Aortic cross-clamp time (p = 0.0004), transfer from the intensive care unit (p = 0.0023), female sex (p = 0.0023), operation performed in early years (p = 0.0041), left ventricular aneurysm (p = 0.0068), the number of diseased coronary vessels (p = 0.0312), and reoperation (p = 0.0318) were all found to be significant independent predictors of increased risk.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

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.

Aged↗
PubMed1995

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.

Blood Flow Velocity↗
PubMed1995

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)

Adult↗
PubMed1995

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.

Abdominal Muscles↗
PubMed1995

Peroperative hemodynamic study of left internal mammary artery grafts.

The present study was undertaken to analyse hemodynamic features of an arterial graft and to determine parameters which influence primarily flow and velocity. A total of 284 consecutive patients having isolated coronary bypass surgery underwent peroperative hemodynamic assessment by pulsed Doppler ultrasonics of a left internal mammary artery bypass graft implanted onto the left anterior descending artery. Internal mammary artery free flow was 109.2 +/- 3.7 ml/min and flow in the internal mammary artery measured after completion of the distal anastomosis was 70.9 +/- 2.7 ml/min. All values quoted are mean +/- standard error of the mean. Mean velocity was 21.2 +/- 0.6 cm/sec, internal diameter was 2.65 +/- 0.04 mm and pulsatility index was 2.24 +/- 0.12. Resistance was expressed as mmHg/(ml . min-1) and averaged 1.65 +/- 0.13 for total resistance, 0.87 +/- 0.05 for graft resistance, and 0.73 +/- 0.13 for coronary resistance. From a set of 35 variables, stepwise multiple regression analysis selected two parameters influencing independently flow in internal mammary artery (R2 = 0.8762): flow velocity (p < 10(-4)) and internal diameter (p < 10(-4)). Variables influencing velocity (R2 = 0.3071) were: pulsatility index, which is a dimensionless expression of peripheral resistance (p < 10(-4)), and free internal mammary artery flow (p = 0.0007). Furthermore, a significant correlation between internal diameter and total resistance was observed (R = -0.5363, p < 10(-4), Y = 1.676X-1.545), and the exponentially fitted regression line was characterized by a marked increase of resistance at diameters less than 2 mm.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Operative risk assessment in coronary artery bypass surgery, 1990-1993: evaluation of perioperative variables.

Patient characteristics and the results of cardiac surgery change with time. To achieve the best possible treatment a continual analysis of results is necessary. The present study analyzes 1225 consecutive patients undergoing isolated aortocoronary bypass surgery for the four-year period ending September 1993. Average age was 63 years (range 32-86 years), 927 (75.7%) patients were male and 298 (24.3%) were female. Hospital mortality was 2.2% (17/787) for elective surgery, 6.3% (21/336) for urgent surgery, and 9.8% (8/82) for emergency surgery. Intraoperative variables increasing independently operative mortality as evidenced by multivariate analysis were the following: prolonged aortic cross-clamping time (p < 0.0001), absence of cold-blood cardioplegia (p = 0.0012), absence of bilateral use of internal mammary artery (p = 0.0035). Likewise, intraoperative variables influencing major adverse outcome (operative mortality and/or need for intra-aortic balloon pulsation) were the following: prolonged aortic cross-clamping time (p < 0.0001), absence of cold-blood cardioplegia (p = 0.0360). In conclusion, global ischemic time was the dominant variable in predicting operative outcome. Furthermore, a protective effect of cold blood cardioplegia and bilateral internal mammary artery grafting was evidenced.

Anesthesia, General↗
PubMed1994

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.

Adult↗
PubMed1994

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)

Adult↗
PubMed1994

Doppler flow measurement in coronary artery bypass grafts and early postoperative clinical outcome.

The present investigation attempts to correlate flow measurements made intraoperatively in coronary bypass grafts with clinical outcome. A total of 352 consecutive patients undergoing isolated coronary artery surgery underwent hemodynamic assessment of their bypass grafts (328 internal thoracic artery and 582 saphenous vein grafts) at the end of cardiopulmonary bypass (CPB) by using a 8 MHz pulsed Doppler ultrasound flowmeter. The total patient population was divided into three groups of distinct outcome (A: normal, 228 patients; B: complicated, 106 patients; C: poor, 18 patients) on the basis of a combination of the following parameters: difficult weaning from bypass, use of inotropic drugs, reduced left-ventricular stroke work index, myocardial infarction, intraaortic balloon counterpulsation, and death of cardiac origin. Univariate analysis has shown clinical outcome to be influenced by preoperative clinical condition and not by flow in bypass grafts (average flow per graft [ml/min] was 60 +/- 2 [mean +/- SEM] in group A, 58 +/- 3 in group B and 43 +/- 6 in group C: NS by analysis of variance). Multivariate analysis (Fisher linear discriminant analysis) selected only the two following factors leading to normal (group A) or adverse (groups B and C) outcome: unstable angina (p = 0.026) and duration of additional CPB after unclamping the aorta (p < 10(-5). To conclude, clinical outcome was not influenced by flow as measured in well-functioning bypass grafts by pulsed Doppler technique.

Blood Flow Velocity↗
PubMed1994

Quantitative angiographic follow-up study of the free inferior epigastric coronary bypass graft.

BACKGROUND: Attempts to improve late results of bypass coronary surgery have focused on the use of arterial conduits because of the high attrition rate of venous grafts. METHODS AND RESULTS: In our institution, 150 patients received an inferior epigastric artery (EPIG) as a free bypass graft, anastomosed to the right coronary artery in 73% and to a marginal branch in 20% of cases. These patients were followed prospectively by qualitative and quantitative angiography. Angiographic studies were performed in 122 patients (81%) early after surgery (11 +/- 5 days), and in 72 cases, a late evaluation (11 +/- 6 months) was also obtained. Quantative angiography (basal and after isosorbide dinitrate [ISDN]) was performed on the in situ EPIG in a large subset of these patients, as well as in 59 patients before bypass surgery. The patency rate was 98% at early control and remained high (93%) at late control. However, at late control, 14 EPIGs were occluded or threadlike, but of these 14, eight were grafted on a coronary artery with a moderate stenosis (< or = 60%) and with good anterograde perfusion. Mean basal EPIG diameter increased from 2.23 +/- 0.42 mm before surgery to 2.57 +/- 0.52 mm at 11 days (P < .01) but decreased to 2.20 +/- 0.47 mm in late study (P < .01 versus 11 days and P = NS versus before surgery). Vasodilation of EPIG with ISDN was observed before surgery (+0.34 +/- 0.20 mm, P < .001) and at late control (+0.20 +/- 0.17 mm, P < .001) but not in the early postoperative period for the whole group. Early after surgery, basal diameter was not different from native EPIG dimensions after ISDN (2.57 +/- 0.52 versus 2.56 +/- 0.39 mm), suggesting maximal dilation. However, vasodilation with ISDN was observed in a subgroup of patients at this time. These responder patients (n = 51) had a smaller basal diameter (2.47 +/- 0.49 versus 2.67 +/- 0.54 mm, P < .05) and a smaller runoff (P < .001) than nonresponder patients. CONCLUSIONS: EPIG grafts have a good early patency rate. The mid-term patency rate remains high and seems to depend, at least partially, on flow through the native coronary artery. EPIGs initially increase their lumen size, probably to meet the increased blood flow due to myocardial requirements. Over time, EPIG diameters decrease mainly as a result of a higher basal vasomotor tone. Long-term angiographic follow-up (eg, 5 to 10 years) is needed to assess late patency rate and the relation with these early findings and will define the place of this new coronary bypass conduit.

Abdominal Muscles↗
PubMed1993

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.

Adolescent↗
PubMed1992

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.

Adult↗