Sevoflurane but not propofol preserves myocardial function in coronary surgery patients

BACKGROUND: Sevoflurane has been shown to protect against myocardial ischemia and reperfusion injury in animals. The present study investigated whether these effects were clinically relevant and would protect left ventricular (LV) function during coronary surgery. METHODS: Twenty coronary surgery patients were randomly assigned to receive either target-controlled infusion of propofol or inhalational anesthesia with sevoflurane. Except for this, anesthetic and surgical management was the same in all patients. A high-fidelity pressure catheter was positioned in the left ventricle and the left atrium. LV response to increased cardiac load, obtained by leg elevation, was assessed before and after cardiopulmonary bypass (CPB). Effects on contraction were evaluated by analysis of changes in dP/dt(max). Effects on relaxation were assessed by analysis of the load dependence of myocardial relaxation (R = slope of the relation between time constant tau of isovolumic relaxation and end-systolic pressure). Postoperative concentrations of cardiac troponin I were followed during 36 h. RESULTS: Before CPB, leg elevation slightly increased dP/dt(max) in the sevoflurane group (5 +/- 3%), whereas it remained unchanged in the propofol group (1 +/- 6%). After CPB, leg elevation resulted in a decrease in dP/dt(max) in the propofol group (-5 +/- 4%), whereas the response in the sevoflurane group was comparable to the response before CPB (5 +/- 4%). Load dependence of LV pressure fall (R) was similar in both groups before CPB. After CPB, R was increased in the propofol group but not in the sevoflurane group. Troponin I concentrations were significantly lower in the sevoflurane than in the propofol group. CONCLUSIONS: Sevoflurane preserved LV function after CPB with less evidence of myocardial damage in the first 36 h postoperatively. These data suggest a cardioprotective effect of sevoflurane during coronary artery surgery.     

Comparative economic analyses of minimally invasive direct coronary artery bypass surgery

OBJECTIVE: This study was undertaken to assess the degree to which published cost comparisons of minimally invasive direct coronary artery bypass through a thoracotomy versus conventional coronary artery bypass grafting, off-pump bypass surgery through a sternotomy, or angioplasty with or without stenting adhered to existing guidelines for performing economic analyses. METHODS: We used minimally invasive direct coronary artery bypass (MIDCAB), off-pump bypass surgery, cost-effectiveness, economic analysis, and related keywords to search MEDLINE, other literature databases and article reference lists for English-language economic analyses of minimally invasive direct coronary artery bypass procedures versus other procedures that were published from 1990 to February 2002. We critically appraised article adherence to a 10-item methodologic checklist modified to address issues particularly relevant to minimally invasive direct coronary artery bypass evaluations. Assessment discordance was reconciled by consensus. RESULTS: Ten articles published from June 1997 to March 2001 compared costs and (generally) outcomes of minimally invasive direct coronary artery bypass with those of other procedures. All were nonrandomized comparisons, generally of concurrent intrainstitutional clinical series. Stated results generally favored minimally invasive direct coronary artery bypass, angioplasty, or off-pump bypass surgery through a sternotomy relative to conventional coronary artery bypass grafting. Studies adequately addressed an average of only 24% of applicable checklist items (range 0%-67%). Few studies adequately ensured the comparability of treatment groups, clearly performed intent-to-treat analyses, comprehensively and credibly measured costs that were considered, or clearly addressed costs and results of preprocedural angiography or postprocedural imaging. Only 1 study compared success of revascularization between minimally invasive direct coronary artery bypass and competing alternatives. No studies specified the cost-analysis perspective or included costs of physician or physician assistant care. CONCLUSIONS: Most published comparative economic analyses of minimally invasive direct coronary artery bypass have failed to adequately address issues crucial to such evaluations. Future studies should more closely follow well-described principles of clinical epidemiology and cost-effectiveness analysis.     

The superiority of pulmonary function after minimally invasive direct coronary artery bypass

OBJECTIVE: We determined whether minimally invasive direct coronary artery bypass (MIDCAB) leads to excellent postoperative pulmonary function, and which contributes more to this--minithoracotomy or avoidance of cardiopulmonary bypass. METHODS: Pulmonary function 1 week before and 2 weeks after surgery was evaluated in 8 patients undergoing MIDCAB (Group M), 10 undergoing off-pump coronary artery bypass (Group O), and 12 undergoing conventional coronary artery bypass grafting (Group C). Parameters were adjusted by their predicted values and postoperative values were expressed as a ratio to preoperative ones. RESULTS: Only Group M maintained postoperative vital capacity and forced expiratory volume in 1 second close to the preoperative level and thus, showed significantly better recovery than Groups O and C. No significant difference was seen between Groups O and C. CONCLUSIONS: MIDCAB provides better recovery of pulmonary function early postoperatively than other procedures thanks to minithoracotomy rather than avoidance of cardiopulmonary bypass.     

Reoperative coronary artery bypass grafting using a minimally invasive direct coronary artery bypass procedure

OBJECTIVE: Reoperative coronary artery bypass grafting with cardiopulmonary bypass tends to cause a higher mortality and morbidity than the primary operation. The purpose of this study was to discuss the effectiveness and safety of a minimally invasive coronary artery bypass procedure for patients who had previously undergone coronary artery bypass surgery. METHODS: We performed redo single coronary artery bypass grafting to the left anterior descending coronary artery in 9 patients and to the right coronary artery in 3 patients using minimally invasive cardiac surgery. The graft to the left anterior descending coronary artery was taken from the left internal thoracic artery in 5 patients, the right gastroepiploic artery in 3 patients, and from the saphenous vein in the other 1 patient. The graft to the right coronary artery was from the right gastroepiploic artery in all 3 patients. RESULTS: All grafts were patent. There was no major postoperative complication and no surgical or hospital death except one late death. CONCLUSIONS: In selected patients, we could safely and completely perform coronary artery bypass re-grafting to the left descending coronary artery or right coronary artery using a minimally invasive operation.     

Refractory coronary artery spasm after minimally invasive direct coronary artery bypass grafting

Postoperative coronary arterial spasm is a rare but potentially fatal complication. A 51-year-old male patient with a history of a reactive ergonovine stress test coronary angiogram developed refractory coronary artery spasm after undergoing minimally invasive direct coronary artery bypass grafting of the left anterior descending coronary artery. The patient was successfully managed with rapid implementation of intra-aortic balloon-pump counter pulsation and extracorporeal membrane oxygenation.     

Cost-effectiveness of minimally invasive coronary artery bypass surgery.

BACKGROUND: Coronary artery bypass grafting without cardiopulmonary bypass is gaining popularity as an alternative to conventional on-pump technique for myocardial revascularization. This includes minimally invasive direct coronary artery bypass (MIDCAB) and full sternotomy off-pump (OPCAB) methods. These two approaches should be evaluated for financial and clinical appropriateness. METHODS: Records of patients who had single or double bypass (internal mammary artery and/or saphenous vein) grafts between January 1997 and June 1998 were reviewed. These included 44 MIDCAB, 62 OPCAB, and 243 conventional coronary artery bypass (CCAB) patients. Univariate analysis was applied to pre, intra, and postoperative variables, comparing MIDCAB and OPCAB to the CCAB group. Procedural cost information was obtained from participating institutions. RESULTS: MIDCAB patients compared to CCAB patients had a higher predicted risk (5.4+/-11 versus 2.3+/-2.8, p = 0.012) and OPCAB patients had a predicted risk of 5.3+/-7.8. MIDCAB and OPCAB procedures required less operating room time and blood utilization. Observed operative mortality rates were MIDCAB 4.5%, OPCAB 1.6%, and CCAB 2.8% (not significant). Mean hospital costs were CCAB at $19,000, OPCAB at $15,000, and $17,000 for MIDCAB. CONCLUSIONS: Off pump procedures currently reflect acute episode-of-care cost savings over CCAB.     

Haemodynamic changes during minimally invasive coronary artery bypass surgery using high-dose esmolol

We aimed to investigate the effects of high-dose esmolol on haemodynamics and oxygen extraction in minimally invasive direct coronary artery bypass (MIDCAB) surgery patients. METHODS: In 18 patients, heart rate (HR), mean arterial (MAP), central venous (CVP), pulmonary capillary wedge pressure (PCWP), cardiac output (CO), and mixed venous oxygen saturation (Sv0(2)) were prospectively measured after induction of anaesthesia (T1), start of surgery (T2), during bypass grafting with beta-blockade (T3), and at the end of surgery (T4). RESULTS: Mean esmolol dose at T3 was 0.44+/-0.2mgkg(-1)min(-1). HR was unchanged, whereas significant decreases in mean CO (3.1+/-0. 8 vs 4.8+/-1.0lmin(-1)m(-2), pre-esmolol), MAP (53+/-10 vs 89+/-14mmHg), and SvO(2) (65+/-10 vs 81+/-4%) were observed during esmolol administration. All haemodynamic parameters normalized immediately after termination of esmolol (T4). CONCLUSIONS: Despite unchanged HR esmolol reduced CO and MAP suggesting a favorable reduction of myocardial oxygen consumption. Mean Sv0(2) during esmolol administration reflects an acceptable ratio of whole-body oxygen delivery and consumption. Haemodynamic changes with high-dose esmolol during MIDCAB surgery remain within safety margins.     

Non steroidal anti-inflammatory drug-based pain control for minimally invasive direct coronary artery bypass surgery

Minimally invasive direct coronary artery bypass (MIDCAB) surgery has become an attractive alternative technique to treat coronary artery insufficiency. Changes in surgical and anesthesia techniques have led to reduced pulmonary morbidity associated with the operation. Early extubation is typically expected. However, postoperative pain management becomes even more important with early extubation. We describe our technique of a NSAID-based protocol with indomethicin and Torodal that has been safe and effective in over 175 patients following MIDCAB.     

Twenty-year outcomes of minimally invasive direct coronary artery bypass surgery: The Leipzig experience

ObjectiveMinimally invasive direct coronary artery bypass (MIDCAB) surgery involving left anterior descending coronary artery grafting with the left internal thoracic artery through a left anterior small thoracotomy is being routinely performed in some specified centers for patients with isolated complex left anterior descending coronary artery disease, but very few reports regarding long-term outcomes exist in literature. Our study was aimed at assessing and analyzing the early and long-term outcomes of a large cohort of patients who underwent MIDCAB procedures and identifying the effects of changing trends in patient characteristics on early mortality.MethodsA total of 2667 patients, who underwent MIDCAB procedures between 1996 and 2018, were divided into 3 groups on the basis of the year of surgery: group A, 1996-2003 (n = 1333); group B, 2004-2010 (n = 627) and group C, 2011-2018 (n = 707). Groupwise characteristics and early postoperative outcomes were compared. Long-term survival for all patients was analyzed and predictors for late mortality were identified using Cox proportional hazards methods.ResultsThe mean age was 64.5 ± 10.9 years and 691 (25.9%) patients were female. Group C patients (log EuroSCORE I = 4.9 ± 6.9) were older with more cardiac risk factors and comorbidities than groups A (log EuroSCORE I = 3.1 ± 4.5) and B (log EuroSCORE I = 3.5 ± 4.7). Overall and groupwise in-hospital mortality was 0.9%, 1.0%, 0.6%, and 1.0% (P = .7), respectively. Overall 10-, 15-, and 20-year survival estimates for all patients were 77.7 ± 0.9%, 66.1 ± 1.2%, and 55.6 ± 1.6%, respectively.ConclusionsMIDCAB can be safely performed with very good early and long-term outcomes. In-hospital mortality remained constant over the 22-year period of the study despite worsening demographic profile of patients.     

To ventilate or not after minimally invasive direct coronary artery bypass surgery: the role of epidural anesthesia

OBJECTIVE: To evaluate the effect of immediate postoperative extubation and postoperative ventilation after minimally invasive direct coronary artery bypass (MIDCAB) surgery and to assess the role of epidural anesthesia. DESIGN: Randomized prospective study. SETTING: University hospital, single institution. PARTICIPANTS: Patients (n = 90) scheduled for elective MIDCAB surgery. INTERVENTIONS: Patients were divided into 3 groups: 30 patients had general anesthesia and were extubated immediately after surgery (extubated group), 30 patients had a thoracic epidural and general anesthesia and were extubated immediately after surgery (epidural group), and 30 patients had general anesthesia and were ventilated after surgery (intubated group). MEASUREMENTS AND MAIN RESULTS: With a similar cardiac index and less vasoactive medication, mean arterial blood pressure (77 plus minus 8 mmHg [mean plus minus SD]) and heart rate (76 plus minus 10 beats/min) in the epidural group were lower on the first postoperative day than in the intubated group (83 plus minus 10 mmHg and 81 plus minus 13 beats/min) and the extubated group (86 plus minus 10 mmHg and 83 plus minus 13) (p = 0.01 and p = 0.09). Oxygenation on the first postoperative day was better in the epidural group than in the intubated group (14.8 plus minus 3.8 kPa v 12.6 plus minus 3.2 kPa; p = 0.05). The epidural group and the extubated group had a transient respiratory acidosis postoperatively. Pain score in the epidural group was lower on the first postoperative day than in the extubated group with general anesthesia (3.0 plus minus 1.6 visual analog scale v 4.6 plus minus 1.8 visual analog scale; p = 0.01). Hospital stay was shorter in the epidural group than in the ventilated group (5.9 plus minus 2.4 days v 8.1 plus minus 5.3 days; p = 0.05) CONCLUSION: Immediate postoperative extubation in patients with thoracic epidural anesthesia and supplemental general anesthesia provides the most favorable clinical circumstances after MIDCAB surgery.     

Milrinone enhances systolic, but not diastolic function during coronary artery bypass grafting surgery

PURPOSE: To evaluate the effect of milrinone on diastolic function during coronary artery bypass grafting surgery (CABG). METHODS: Fifty patients undergoing CABG were randomized to receive a bolus and infusion of milrinone or placebo before cardiopulmonary bypass (CPB) until skin closure. Hemodynamic and transesophageal echocardiographic measurements of systolic and diastolic function were obtained. Pulsed wave Doppler measurements of the early (E wave) and atrial components (A wave) of the transmitral (TMF) and transtricuspid (TTF) flows, and systolic (S wave), diastolic (D wave) and atrial components (Ar) of the pulmonary (PVF) and hepatic venous blood flow (HVF) velocities were performed. Early and atrial components of the mitral (Em and Am waves) and tricuspid annulus velocities (Et and At waves) were assessed by tissue Doppler imaging (TDI). Assessment of diastolic dysfunction was graded from normal to severe using a scale score. RESULTS: Cardiac index and heart rate were higher in the milrinone group compared to placebo after the administration of study drug (2.8 +/- 0.6 vs 2.1 +/- 0.5 L.min(-1)m(-2)) (P < 0.0001) and (67 +/- 8 vs 60 +/- 12 beats.min(-1)) (P < 0.05) respectively. There were no changes in left and right ventricular diastolic dysfunction scores between study groups. Higher PVF S wave, HVF S wave, TTF A wave and At measured by TDI in the milrinone group compared with placebo suggested an improvement in ventricular systolic and atrial contraction. CONCLUSION: Distinct from its effects on systolic function, milrinone administered before CPB is not with associated improved biventricular diastolic function in patients undergoing CABG.     

Vascular clamp for hemostasis and stabilization during minimally invasive direct coronary artery bypass.

A soft vascular clamp was used for hemostasis and stabilization of the operative field during minimally invasive direct coronary artery bypass (MIDCAB). The instrument was gently applied so that it clamps the coronary artery by grasping the adjacent myocardium. The method offered dry and stable operative field without a special instrument or technique. The surgical results have been satisfactory. We found application of the vascular clamp to be very helpful for MIDCAB.     

Surgical results of video-assisted minimally invasive direct coronary artery bypass.

BACKGROUND: A video-assisted minimally invasive direct coronary artery bypass procedure is defined as a combination of video thoracoscopic internal mammary artery harvest and direct coronary bypass grafting through a minithoracotomy without cardiopulmonary bypass. We reviewed our experience with this procedure and examined its efficacy. METHODS: Since November 1995, 110 patients have undergone a minimally invasive direct coronary artery bypass procedure in our institution. Seventy (64%) of them underwent a video-assisted minimally invasive operation (group 1). As a control group (group 2), we reviewed the results in 37 patients who underwent conventional single or double coronary artery bypass grafting using an internal mammary artery graft between 1993 and 1995 and could have been candidates for minimally invasive direct coronary artery bypass grafting. RESULTS: There were two hospital deaths (2.9%) in group 1 and one hospital death (2.7%) in group 2. There were no significant differences in mortality or morbidity between the two groups. The number of patients who needed postoperative positive inotropic agents was significantly greater in group 2, and this group also had a significantly longer mean postoperative intubation time and mean hospital stay than group 1. CONCLUSIONS: The surgical results of video-assisted direct coronary artery bypass procedures were better than those of conventional coronary artery bypass grafting in this review. A long-term follow-up for graft patency is needed.     

Delayed cardiac tamponade after minimally invasive direct coronary artery bypass.

We experienced a rare case of delayed cardiac tamponade after minimally invasive coronary artery bypass (MIDCAB). Pericardial effusion was successfully drained under ultrasonic guidance.     

The clinical outcome and quality of life following minimally invasive direct coronary artery bypass surgery

BACKGROUND: Minimally invasive direct coronary artery bypass (MIDCAB) through a limited anterior small thoracotomy has been shown to be a promising technique of surgical treatment for single or double vessel disease. Little is known about the Health-Related Quality Of Life (HRQOL) in this group of patients. METHODS: The records of 75 consecutive patients who underwent MIDCAB procedure at Harefield Hospital between April 2000 and January 2002 were reviewed retrospectively. HRQOL assessment was planned in a cross-sectional design. Patients were contacted by telephone to conduct a semi-structured interview and were sent two questionnaires: the Short Form health survey (SF-36) and the Hospital Anxiety and Depression Scale (HADS). RESULTS: There was no in-hospital death. Patients stayed in the Intensive Therapy Unit (ITU) for 11.56 +/- 4.55 hours and stayed in hospital for 3 +/- 2.34 days. None of the study patients had perioperative myocardial infarction (MI) or neurological complications including permanent and transient strokes. We were able to contact all the 75 patients by telephone and they also completed the SF-36 and HADS. The SF-36 scores were compared to an age-matched group of normal British people. The MIDCAB group had an excellent general health perception compared to the normal group (p < 0.001), but similar scores otherwise. The HADS scores showed that only 1 patient (1.3%) had mild depression, 5 patients (6.7%) had mild anxiety, and 2 patients (2.6%) had moderate anxiety. CONCLUSION: MIDCAB is a safe surgical treatment and provides excellent clinical and HRQOL outcomes.     

Determinants of late outcome after minimally invasive direct coronary artery bypass

AIM: Minimally invasive direct coronary artery bypass (MIDCAB) is a reliable method to revascularize the left anterior descending (LAD) coronary artery. However, a more consistent body of knowledge is needed to assess factors influencing long-term outcome. With this study, we retrospectively investigated the long-term determinants of survival and freedom from cardiac morbidity and revascularization in patients who underwent MIDCAB. METHODS: From 1997 to 2005, 109 patients underwent MIDCAB. Seventy-five (68.8%) presented isolated LAD disease and 34 (31.2%) multivessel disease. The first 57 patients (53.2%) in the series underwent early postoperative angiographic reinvestigation. All 109 patients were subsequently followed-up at our outpatient clinic. Follow-up (mean 50.7 months, range 3-93) was completed in 100% of cases. RESULTS: No in-hospital deaths occurred; 2 patients (1.8%) experienced perioperative myocardial infarction. At early postoperative angiographic reinvestigation, the anastomotic perfect patency rate was 54/57 (94.7%); survival was 100% and 95.8% at 1 and 5 years, respectively. Overall freedom from repeated revascularization was 95.3% and 88.3% at 1 and 5 years respectively; freedom from LAD revascularization was 95.3% and 91.6% at 1 and 5 years, respectively; cardiac event-free survival was 95.3% and 80.8% at 1 and 5 years respectively. At multivariable analysis (Cox regression), women were found to have a higher risk of repeated LAD revascularization (hazard ratio [HR] 30.24; P<0.001); female sex and left ventricular dysfunction were the only predictors affecting long-term cardiac outcome (hazard ratio 29.35; P<0.001 and 5.1; P<0.001), respectively. CONCLUSIONS: A key factor in the long-term success of MIDCAB seems to be appropriate patient selection. Special attention should be reserved for female patients, as they appear to have a worse cardiac outcome and a higher probability of repeated revascularization on LAD. MIDCAB may represent a viable option for treating multivessel disease when complete revascularization is unfeasible or a hybrid procedure is envisaged.