Renal dysfunction after myocardial revascularization.

OBJECTIVES: In this study, we evaluate the incidence of and analyse the pre and intraoperative risk factors for the development of postoperative renal dysfunction (PRD), and the impact of such an event on perioperative mortality and on hospital length of stay. In addition, we sought to investigate the influence of a mildly increased serum creatinine (1.3-2.0 mg/dl) on perioperative mortality and morbidity. METHODS: The study included 2445 consecutive patients who had no pre-existing renal disease (creatinine or=2.1 mg/dl with a preoperative-to-postoperative increase >or=0.9 mg/dl. Univariate and multivariate analyses were performed where appropriate. RESULTS: Global 30-day mortality was 0.7%. The incidence of PRD was 5.6% (136 patients). Mortality for patients who experienced PRD was 8.8 vs. 0.1% for patients who did not (P<0.001). PRD increased the length of hospital stay by 3.4 days (7.6 vs. 11.0 days; P<0.001), and patients who needed haemodialysis (11%) had a perioperative mortality of 33.3% and a mean hospital length of stay of 16 days. Multivariable logistic regression identified the following variables as independent predictors of PRD: age (P=0.017; odds ratio (OR) 1.3 per 10 years), angina class III/IV (P=0.003; OR 1.7); cardiopulmonary bypass time (P=0.007; OR 1.01 per minute); preoperative serum creatinine levels: group 1 (1.3-1.6 mg/dl (P<0.001; OR 5.5)) and group 2 (1.7-2.0 mg/dl (P<0.001; OR 14.2)). Finally, a mild elevation of the preoperative creatinine level (1.3-2.0 mg/dl) increased significantly the probability of perioperative mortality, low cardiac output, haemodialysis and prolonged hospital stay. CONCLUSIONS: Although the likelihood of PRD in patients without pre-existing renal dysfunction is relatively low, it dramatically increases mortality, morbidity and length of stay after CABG. Mildly elevated (>1.2 mg/dl) preoperative serum creatinine level significantly increases the perioperative mortality and morbidity.     

Coronary artery revascularization after myocardial infarction.

Authors report on the revascularization resulted by noninvasive and invasive interferences carried out 6-9 months after surgery and on the improvement of functional status of 56 postinfarction patients with recurrent angina pectoris. They conclude that recoronarography performed in 12 patients revealed diminished patency rate as compared to the estimated rate, especially in those cases, where complete revascularization was considered to have been carried out. Ejection fraction, wall motion score by ventriculography and echocardiography did not seem to improve significantly. However Dipyridamole Thallium scintigraphy showed marked improvement in perfusion in all cases. NYHA functional status noticeably improved in the re-examined patients.     

Risk of major elective operation after myocardial revascularization.

Although an increased surgical risk of ischemic myocardial disease is widely accepted, amelioration of this risk after coronary artery bypass is poorly defined. We compared the outcomes of major elective general and peripheral vascular operations in 181 patients with prior coronary artery bypass grafting (CABG) with outcomes in an age-, gender-, and procedure-matched group without prior CABG (NOCABG). Despite the perception of a greater operative risk in the CABG patients (more CABG patients in American Society of Anesthesiologists [ASA] class III and fewer in ASA class I, p < 0.001), mortality (1.1% CABG versus 2.8% NOCABG) and morbidity (18.8% CABG versus 18.5% NOCABG) rates in the two groups were not significantly different. For patients who have undergone successful CABG, it appears that: (1) the risk of subsequent elective major general and vascular surgical operations is similar to that of an age-, gender-, and procedure-matched cohort, and (2) the mortality rate after elective operations is low.     

Prognostic value of preoperative quality of life on mortality after isolated elective myocardial revascularization

OBJECTIVES This study evaluates whether a low preoperative quality of life (QoL), measured with the EuroQoL instruments EQ-5D and EQ-visual analogue scale (VAS) can be used as a predictor of mortality after elective isolated myocardial revascularization. METHODS A total of 2501 patients, with a mean age of 65.3?±?9.4 (range 18-93) years and a mean additive EuroSCORE of 2.7?±?2.1 (0-12), undergoing an elective isolated coronary artery bypass graft between January 2002 and June 2011 completed preoperative EQ-5D and EQ-VAS. RESULTS Hospital mortality [1.0% (25/2501 patients)] and 30-day mortality [1.2% (29/25 patients)] were the studied outcomes. The EQ-5D was 0.69?±?0.26 (-0.30 to 1.0) with a median of 0.77 and the EQ-VAS was 59.7?±?22.4 (0-100) with a median of 60. Regression analysis showed a significant correlation between hospital mortality and EQ-5D (P?=?0.016) and EQ-VAS (P?=?0.033). There is a significant correlation between 30-day mortality and EQ-5D (P?=?0.048), but not for EQ-VAS (P?=?0.06). The c-statistics (95% confidence interval) for EQ-5D and EQ-VAS for predicting hospital mortality are 0.36 (0.24-0.46) and 0.33 (0.23-0.42), respectively. The c-statistics for predicting 30-day mortality are 0.39 (0.30-0.49) for EQ-5D and 0.35 (0.26-0.44) for EQ-VAS. CONCLUSIONS Based on these results, we conclude that, in isolation, poor low preoperative EQ-5D and EQ-VAS scores do not contribute to deciding which patients should undergo cardiac surgery.     

Determinants of 10-year survival after primary myocardial revascularization.

The first 1000 patients undergoing primary isolated myocardial revascularization each year from 1971 to 1978 were analyzed to elucidate the determinants of long-term survival. Five-year survival was 93.2%, and 10-year survival was 79.3%. Five-year survivals were 96.1%, 94.2%, 92.1%, and 90.8%, respectively, for single, double, triple, and left main disease. Ten-year survivals for the same subsets were 88.6%, 83.0%, 74.9%, and 70.9%. Five-year survivals were 95.3%, 92.4%, 88.0%, and 81.3% for patients with normal, mild, moderate, and severe impairment of the left ventricle. Ten-year survivals for the same subsets were 84.1%, 76.5%, 65.8% and 53.6%. Patients receiving internal mammary artery grafts had 95.6% and 85.8% 5- and 10-year survivals that were superior to 92.0% and 76.2% in patients with only vein grafts. Patients completely revascularized had 95.0% and 82.5% 5- and 10-year survivals, while incompletely revascularized patients had lower (90.5% and 75.2%) 5- and 10-year survivals. Advancing age was the most important factor influencing late survival. Other risk factors in descending order of significance were impaired left ventricular function, no mammary artery graft, smoking, abnormal EKG, three vessel or left main disease, left ventricular end diastolic pressure (LVEDP) greater than 24, hypertension, 1971 to 1974 surgical era, cholesterol greater than 300, incomplete revascularization, and two vessel disease.     

Prevention of ventricular fibrillation after myocardial revascularization

Ventricular fibrillation during reperfusion after aortic cross-clamping for coronary artery bypass grafting may cause subendocardial injury. We investigated the use of lidocaine to prevent ventricular fibrillation during this period. In a blind, prospective, randomized trial, 91 consecutive patients undergoing elective coronary artery bypass graft procedures were given lidocaine (2 mg/kg) or normal saline immediately before removal of the aortic cross-clamp. The groups were similar with respect to demographic, clinical, and intraoperative variables. Myocardial preservation techniques were similar in both groups. Of 47 patients receiving lidocaine, 38 recovered a supraventricular rhythm without ventricular fibrillation, compared with only 5 of 44 patients in the control group (p less than .001). When ventricular fibrillation occurred, patients in the control group required a greater number of direct-current countershocks (2.31 versus 1.86) to convert to sinus rhythm. Transient heart block, requiring temporary pacing, developed in 3 patients in the lidocaine group, compared with 1 patient in the control group. There was no significant difference between the groups in the requirement for perioperative inotropic support (6 of 47 versus 6 of 44) or the number of myocardial infarctions (2 of 47 versus 1 of 44), and there were no deaths in either group. Lidocaine infusion immediately before removal of the aortic cross-clamp significantly reduces the incidence of ventricular fibrillation during the reperfusion period after cardiopulmonary bypass.     

Reoperations for myocardial revascularization.

Reoperations solely for myocardial revascularization were performed in 219 consecutive patients (1967 to 1975). Indications were (1) graft failure, 46 (21 per cent); (2) progressive atherosclerosis, 42 (19 per cent); (3) incomplete revascularization, 39 (18 per cent); and (4) combinations, 92 (42 per cent). Primary operations included bypass grafts in 100 patients; mammary artery implants, 87; and combinations of direct and indirect procedures, 32. Reoperations performed were single bypass, 141 patients; double, 61; and triple or other coronary artery operations, 17. Eight patients died within 30 days of operation (3.7 per cent). Major postoperative complications included hepatitis, 24 (11 per cent); myocardial infarction, 19 (9 per cent); bleeding, 21 (10 per cent); and respiratory insufficiency, 12 (5 per cent). Follow-up for 202 long-term survivors was complete (mean 29 months). In patients who originally underwent direct revascularization, Class I or II (N.Y.H.A.) was attained in 35 of 43 (81 per cent) of those reoperated upon for primary graft failure, in 14 of 15 (93 per cent) of those with progressive atherosclerosis, and in 27 of 33 (82 per cent) of patients with combined indications. Arteriography was performed after the reoperation in 55 patients (mean interval 17 months), and 65 of 77 (84 per cent) grafts were patent. Nineteen of 22 grafts performed for primary graft failure were patent. We have made the following conclusions: (1) Reoperation for direct myocardial revascularization can be accomplished with low mortality rates although morbidity is high; (2) complete relief of symptoms was achieved in 65 per cent of survivors; (3) results in patients reoperated upon for graft failure alone were similar to results in those operated upon for progressive atherosclerosis or combined indications; and (4) high graft patency was found in secondary grafts constructed to arteries involved with primary graft failure.     

Quality of life in patients over 70 years of age after heart valve replacement.

BACKGROUND: Previous studies on valve replacement in patients over 70 years of age have been concerned with early and long-term outcome. Little is known, however, of the quality of life (QOL) of survivors following surgery. METHODS: Thirty-one consecutive patients, mean age 74.0+/-3.1 years, who underwent heart valve replacement were reviewed and questioned as to their physical and social activities before and after surgery and compared with 75 patients aged less than 70 years old who underwent similar procedures during the same time interval. QOL was measured by using the Rosser distress and disability scores. RESULTS: Hospital mortality in the elderly group was the same as in the younger group (9.7% vs 2.7%, p = 0.121). Median 5-year survival was 79% in the elderly group and 92% in the younger group (p = 0.068). Overall morbidity due to valve-related complications was 3.55%/patient-year in the elderly group and 2. 35%/patient-year in the younger group, and freedom from all valve-related complications at 5 years was 76%, and 83%, respectively (p = 0.202). There were significant improvements in the distress and disability scores postoperatively (mean interval: 32. 4+/-20.4 months). The QOL value rose from 0.960 to 0.981 in the elderly group (p = 0.0004), and from 0.975 to 0.984 in the younger group (p = 0.07), suggesting that the magnitude of improvement in the elderly group was superior to that in the younger group. CONCLUSIONS: Heart valve replacement in patients over the age of 70 years was associated with reasonable early and mid-term morbidity. We believe that significant improvements in the symptoms, functional status, and QOL of the patients can be expected.     

Quality of life and survival after transmyocardial laser revascularization with the holmium:YAG laser

BACKGROUND: The purpose of this investigation was to assess postoperative survival and quality of life with transmyocardial laser revascularization (TMR) in high-risk patients. METHODS: During a 24-month period, 81 consecutive patients underwent either sole therapy TMR (n = 34) or TMR with coronary artery bypass grafting (n = 47) using a holmium:yttrium-aluminum-garnet (YAG) laser. Outcomes were assessed in three high-risk groups, including patients with left ventricular dysfunction (ejection fraction < or = 0.40) (n = 37), unstable angina (n = 30), and congestive heart failure (n = 33). Disease-specific quality of life was assessed using the Seattle Angina Questionnaire in 58 late survivors and compared with an age-matched cohort undergoing coronary artery bypass grafting only (no TMR) (n = 20). RESULTS: Overall mortality was 6% +/- 3% (+/- 70% confidence limit) and appeared higher with left ventricular dysfunction (11% +/- 5% vs 2% +/- 2%), but the difference did not reach statistical significance (p = 0.17; power = 0.16). There was also no statistical difference with unstable angina (10% +/- 6% vs 4% +/- 3%; p > 0.53) or congestive failure (9% +/- 5% vs 4% +/- 3%; p > 0.66). However, survival at 18 months was significantly lower with left ventricular dysfunction (62% +/- 9% vs 90% +/- 5%; p < 0.003) and congestive failure (48% +/- 10% vs 96% +/- 3%; p < 0.001). For sole therapy TMR, quality of life was diminished comparing TMR with coronary artery bypass grafting (p < 0.004) and coronary artery bypass grafting only (p < 0.002). CONCLUSIONS: Transmyocardial laser revascularization can be performed in high-risk patients, but survival is significantly impaired in patients with left ventricular dysfunction and congestive failure, and quality of life is diminished without some degree of direct revascularization.     

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.     

Comparison of two transfusion strategies after elective operations for myocardial revascularization.

We performed a prospective, randomized trial of two different strategies for postoperative packed red blood cell replacement in 39 autologous blood donors undergoing elective myocardial revascularization. The "liberal" group received blood to achieve a hematocrit value of 32%, and the "conservative" group received transfusions for a hematocrit value less than 25%. Although the groups had significantly different mean hematocrit values from the fourth postoperative hour (28.7% versus 31.2%) through the fifth postoperative day (28.4% versus 31.3%), there were no significant differences in fluid requirement, hemodynamic parameters, or hospital complications. Significantly fewer units of packed cells were required in the conservatively transfused group (20 units/20 patients) compared with the liberally transfused group (37 units/18 patients) (p = 0.012). Exercise tests were performed on the fifth and sixth postoperative days, with a transfusion being given to the conservative group between tests. Although a significant improvement in exercise endurance occurred in the conservative group receiving a transfusion (p = 0.008), no significant difference in duration or degree of exercise was demonstrated between the two groups on either day. In comparing these two groups of profoundly anemic patients, we identified no adverse consequence associated with the greater degree of hemodilution and could identify no correlation between hematocrit value and exercise capacity. We conclude that although the limits of hemodilution are still poorly defined, postoperative blood transfusion in revascularized patients should be guided by clinical indications and not by specific hematocrit values.     

Quality of life after major burns.

The only presently available method of measuring the outcome of major burns is the mortality rate. We have developed a scale, administered by interview and physical examination, with which the quality of life in survivors may be measured. In an initial group of 32 patients, we took each patient's own preinjury level of performance as a baseline. The size of the burn had no significant effect on the postburn score achieved. Substantial numbers of patients achieved levels superior to their preburn score. Improvement in scores did not begin until 12 months had elapsed from the time of injury. We feel that scales such as this will help determine what happens to patients after their injury, pinpoint areas of weaknesses in the burn program, and enable better comparison of performance between clinical facilities.     

Quality of life after reduction mammaplasty.

Reduction mammaplasty is a common procedure in plastic surgery. Patients seek the operation for neck and lower back pain, and social and emotional problems. The evaluation of health results based on the patient's opinion has become an important and reliable method for the analysis of alterations resulting from treatment. To evaluate the impact of plastic surgery on the quality of life of patients with mammary hypertrophy we used the SF-36 standardised questionnaire in a prospective study of 44 patients preoperatively and three and six months postoperatively. There were significant improvements in seven of the eight aspects of the SF-36 (physical function, physical role, pain, energy, social function, emotional role, and mental health). Only general health was unchanged.     

CK-MB isoenzyme in the diagnosis of myocardial infarction after myocardial revascularization surgery

The usefulness of measuring serum MB creatine kinase activity (CK-MB) for the diagnosis of per- and postoperative myocardial infarction (MI) was assessed in 104 patients undergoing coronary artery bypass grafts. In each patient, 15 samples were taken during the week which followed the surgical procedure. New Q waves were considered to be a criteria of MI. 19 patients developed new Q waves (MI group), whereas 57 had no significant ECG changes (control group); 13 showed only ST changes, whilst 15 had unassessable recordings. In the MI group, CK-MB was greater than in the control group, both at the first peak (8 to 10 h after induction of anaesthesia) and at the greater peak (13 to 21 h after induction) (p less than 0.05). Significant differences were also seen between both groups between 8 and 32 h after induction, but there was also a large overlap. An area under the curve (AUC) greater than 50,000 IU.l-1.min-1 had a positive predictive value of 0.64, and an AUC less than 50,000 IU.l-1.min-1 a negative predictive value of 0.89 if all the groups of patients were taken into account. An AUC greater than 65,000 IU.l-1.min-1 was always seen in MI patients, but only 25% of MI patients had a value greater than this threshold. There were no significant differences between the patient groups in the first peak time, nor in the CK-MB/total CK ratio. CK-MB appeared therefore as a less reliable criterium of per- and postoperative MI during coronary artery bypass operations than previously reported, especially when intermediate values are found.     

Assessment of health-related quality of life after coronary revascularization

The use of patient-oriented outcomes, in particular health-related quality if life (HRQOL), to evaluate coronary revascularization is continuously increasing. Current data underline that patients undergoing conventional CABG show a tremendous improvement of HRQOL status as early as 3 months postoperatively. There seems to be no clear benefit concerning HRQOL for off-pump coronary surgery versus conventional CABG. The benefits of minimal invasive CABG via mini-thoracotomy are compromised by increased incidence of pain during the immediate postoperative period. Totally endoscopic approaches seem to be more effective with regard to pain reduction and resume of every day activities. Compared to catheter-based interventions there is evidence that conventional CABG offers significant advantages over PCI. The influence of drug-eluting stents and newer surgical techniques on HRQOL remains to be determined. Inclusion of HRQOL data in CABG and PCI databases can play a central role in order to identify patient groups who benefit the most from each revascularization strategy.     

Blood conservation during myocardial revascularization.

A prospective study of blood utilization in 50 consecutive patients undergoing elective coronary artery bypass was undertaken. Blood was removed from all patients during induction of anesthesia and reinfused after bypass (mean, 675 ml). Intraoperatively, all discard suction was routed through a regionally heparinized collecting and processing system, and the resulting red cell concentrate was transfused. At the conclusion of bypass, all blood remaining in the pump oxygenator was retained for transfusion. After operation, shed mediastinal blood was collected in a sterile, filtered collection system and transfused. Normovolemic anemia was accepted in hemodynamically stable patients. The mean amount of patients' blood salvaged by the intraoperative system was 259 ml (range, 0 to 724 ml) and by the postoperative system, 194 ml (range, 0 to 564 ml). Ninety-four percent (47/50) of the patients received no bank blood or blood products during their hospital stay. No patients received bank blood intraoperatively or during the first 24 hours following operation. There were no complications attributable to blood salvage techniques.