The π-Circuit Technique in Coronary Surgery: Analysis of 1359 Consecutive Cases.

Coronary artery bypass surgery still has its unique role in the treatment of coronary artery disease. It faces, however, the continuous challenge of becoming even less invasive and more effective as cases become more complex. We here present the results of 1359 cases treated with the π-circuit technique which consists of an off-pump total myocardial revascularization using composite arterial grafts. The results demonstrate that it is a safe technique providing low mortality, stroke, renal failure, wound infection, and other complication rates. We suggest the application of this technique, as well as of other similar techniques regarding similar principles, especially in high-risk patients.

Current options for treatment of chronic coronary artery disease.

The primary issues must be discussed regarding the decision making of treating a patient with chronic coronary artery disease (CAD), are the appropriateness of revascularization and the method which will be applied. The criteria will be the symptoms, the evidence of ischemia and the anatomical complexity of the coronary bed. Main indications are persistence of symptoms, despite oral medical treatment and the prognosis of any intervention. The prognosis is based on left ventricular function, on the number of coronary arteries with significant stenosis and the ischemic burden. For patients with symptoms and no evidence of ischemia, there is no benefit from revascularization. If ischemia is proven, revascularization is beneficial. If revascularization is decided, the next important issue must be taken under consideration is the choice of the appropriate method to be applied, surgical or interventional approach. Current treatment options will be presented.

Impact of obesity on outcome of patients undergoing off-pump coronary artery bypass grafting using aorta no-touch technique.

We prospectively examined 1359 adult patients undergoing isolated coronary revascularization with the Pi-circuit technique, consisting of beating heart, aorta no-touch, use of composite grafts, and off-pump arterial revascularization. Patients were divided into two groups based on body weight; Group A consisting of 295 (21.7%) obese patients [body mass index (BMI) > or =30 kg/m(2)] and Group B of 1064 (79.3%) non-obese patients (BMI <30 kg/m(2)). Advanced age and emergency surgery favored the non-obese group [63.0+/-10.4 vs. 65.3+/-9.6 years (P<0.0005) and 10.2% vs. 17.1% (P=0.004), with an increase in the number of octogenarians among them (1.7% Group A vs. 5.4% in Group B, P=0.11)]. The use of double internal mammary arteries (90.5% in Group A vs. 86.9% in Group B, P=0.109), the mean number of distal anastomoses (2.8+/-0.9 in Group A vs. 2.7+/-0.9 in Group B, P=0.5) and the number of sequential anastomoses performed (28.1% in Group A vs. 31% in Group B, P=0.3) were similar. No difference in morbidity rates was detected. All cause in-hospital mortality was comparable. Survival was similar in both groups also. Obesity is not a risk factor for morbidity and mortality in this group of patients.

Female risk using OPCAB, pi-circuit, and aorta no-touch coronary revascularization.

BACKGROUND: In this study, we evaluated female sex as a risk factor in the off-pump coronary artery bypass (OPCAB), aorta no-touch technique. MATERIALS AND METHODS: From February 2001 to November 2005, 1359 patients in our institution underwent isolated coronary revascularization with the pi-circuit technique, which consists of (1) beating heart surgery, (2) OPCAB, (3) no touching of the aorta, (4) use of composite grafts, and (5) arterial revascularization. There were 1159 men (group A) and 200 women (group B). Both groups were compared with respect to preoperative risk factors, intraoperative parameters, and postoperative morbidity and mortality. Follow-up lasted from 4 to 60 months. Data were analyzed with the chi(2) test, the Fisher exact test, the Kaplan-Meier method, and the Cox model of regression analysis. RESULTS: Female patients were older (P < .0005) and had higher prevalences of obesity (P < .0005), arterial hypertension (P < .0005), and diabetes (P < .0005). Emergency operations were also more frequent in this group (P < .027). There was no difference between the groups in the preoperative use of an intra-aortic balloon pump (IABP). The 2 groups were not significantly different with respect to 30-day mortality (1.1% versus 4%) or 7-day mortality (0.3% versus 0%). The 2 groups had comparable rates of IABP use postoperatively. Cognitive disturbances and strokes were rarely encountered (0.6% in men and 0.2% in women). In the early postoperative phase, women had more pulmonary complications (P < .014), and survival seemed to favor the male group during the follow-up period (P < .001). Further analysis with the Cox regression model with exclusion of confounding preoperative morbidity factors (more prevalent in group B) showed that the 2 groups had similar survival rates. As a group, women were 1.06 times more likely to die from a cardiac cause than men (P < .897). CONCLUSIONS: The use of the pi-circuit, aorta no-touch technique is equally effective and safe for both sexes. Women are more prone to pulmonary complications in the early postoperative phase. The apparent difference in survival favoring men can be attributed to the higher prevalence of preoperative risk factors in women. In general, we consider the off-pump, aorta no-touch technique an effective method for lowering morbidity and mortality in the relatively high-risk female patient group.

Aorta no-touch off-pump coronary artery revascularization in octogenarians: 5 years' experience.

BACKGROUND: Approximately 18% of octogenarians have ischemic heart disease. Increasingly, they are being referred for coronary artery revascularization by surgical and/or percutaneous procedures. These strategies have been questioned, however, because of reports of poor outcomes in the elderly. In this study, we aimed to determine the impact of age on morbidity and mortality in patients undergoing off-pump coronary artery bypass (OPCAB) with the pi-circuit procedure during 5 years of follow-up. MATERIALS AND METHODS: From February 2001 to November 2005, 1359 patients underwent isolated coronary revascularization with the pi-circuit technique, which consists of (1) beating heart surgery, (2) OPCAB, (3) no touching of the aorta, (4) use of composite grafts, and (5) arterial revascularization. Sixty-two patients were > or = 80 years of age (group A), and 1297 were <80 years old (group B). Both groups were compared with respect to preoperative risk factors, intraoperative parameters, and postoperative morbidity and mortality. Follow-up lasted from 4 to 60 months. Data were analyzed with the chi(2) test, the Fisher exact test, the Kaplan-Meier method, and the Cox model of regression analysis. RESULTS: Females predominated among the octogenarians (P < .0005). Octogenarians more frequently underwent emergent operations (P < .031) and had worse ejection fractions (P < .026). Obesity was also less prevalent among these patients (P < .007). There were no differences between the groups in the preoperative and postoperative use of an intraaortic balloon pump. Octogenarians had lower cholesterol levels (P < .0005) and had fewer distal anastomoses (2.24 + or - 0.0.76 versus 2.77 + or - 0.92, P < .0005). The 2 groups were not significantly different with respect to 30-day mortality (3.2% versus 1.5%) and 7-day mortality (1.6% versus 0.2%). Differences were noted in the incidences of pulmonary complications (12.9% versus 5.6%, P < .027), atrial fibrillation (41.9% versus 19%, P < .0005), and cognitive disturbances (6.5% versus 0.3%, P < .0005). During follow-up, survival seemed to favor the younger group (P < .001). Nevertheless, further analysis of the data with the Cox regression model to exclude confounding risk factors, revealed the survival rates of the 2 groups to be similar. CONCLUSIONS: Use of the pi-circuit technique is very effective for octogenarians. Although these older patients have a higher incidence of early postoperative morbidity, overall survival is not affected.

Nosocomial infections after off-pump coronary artery bypass surgery: frequency, characteristics, and risk factors.

We evaluated the frequency, risk factors, and characteristics of infections in 360 patients after off-pump coronary artery bypass grafting (OPCABG). A prospective study was performed during the period June 2004-October 2005 at Henry Dunant Hospital, Athens, Greece. C-reactive protein (CRP) and procalcitonin were assayed from 222 patients preoperatively, and 1-3 days following OPCABG. Variables independently associated with infection were identified by a multivariable logistic regression model. Eighteen of 360 (5%) patients developed postoperative infections; 1.7% developed superficial wound infection, 1.4% pneumonia, 1.1% bacteremia, 0.3% mediastinitis, and 0.3% intra-aortic balloon pump related infection. The mean increase of CRP and procalcitonin levels in the first two or three days, respectively, after surgery was significantly higher (P<0.05) in patients with infection. Independent risk factors of infection (P<0.05) were history of major nervous system disorder, left ventricular heart failure preoperatively, emergent operation, transfusions of red blood cells during ICU stay, and duration of central venous catheter placement. The identification of risk factors for infection in combination with the appropriate evaluation of the increased CRP and procalcitonin values may help clinicians for the early diagnosis of infection after OPCABG.

Predictors of prolonged mechanical ventilation following aorta no-touch off-pump coronary artery bypass surgery.

OBJECTIVE: To identify parameters associated with prolonged mechanical ventilation (PMV) (>48 h) after off-pump coronary artery bypass (OPCAB) in our patient population. MATERIALS AND METHODS: From February 2001 to November 2005, we operated on 1359 patients for isolated coronary revascularization with the pi-circuit technique, consisting of: (1) beating heart, (2) OPCAB, (3) aorta no-touch, (4) use of composite grafts, and (5) arterial revascularization. RESULTS: From the total number of our patients, 1320 patients had been extubated within 48 h postoperatively (Group A) and 39 patients needed PMV (Group B). In our study we have found that PMV were associated with advanced age (64.74+/-9.85 Group A vs 68.43+/-10.03 Group B, p<0.02) as well as higher incidence with octogenarians (4.4% Group A vs 10.2% Group B, p=0.09). Patients with preoperative history of transient ischemic attacks (TIAs) or stroke were more likely to belong to Group B (1.5% Group A vs 7.7% Group B, p<0.02; 2.8% Group A vs 10.3% Group B, p<0.02, respectively). Preoperative intra-aortic balloon pump (IABP) insertion was associated with PMV (1.6% Group A vs 15.4% Group B, p<0.0005). Unexpectedly, neither COPD nor obesity was associated with PMV (4.9% Group A vs 7.7% Group B, p=NS, 21.7% Group A vs 23.1% Group B, p=NS, respectively). CONCLUSION: In this study, PMV following aorta no-touch OPCAB was related to preoperative variables: age, octogenarians, preoperative IABP, TIA, and stroke. There was no relation between PMV and any of the operative data.

Microbiologically documented nosocomial infections after coronary artery bypass surgery without cardiopulmonary bypass.

OBJECTIVE: This study was undertaken to evaluate the frequency, characteristics, and risk factors of microbiologically documented nosocomial infections after off-pump coronary artery bypass grafting. METHODS: A prospective cohort study was performed at Henry Dunant Hospital, Athens, Greece. It included all adult patients who underwent coronary artery bypass grafting with no valve surgery and without the use of cardiopulmonary bypass during a period of 3 years. Case patients were those with development of microbiologically documented nosocomial infections. Various variables were examined as possible risk factors for nosocomial infections. RESULTS: Twenty-one of 782 studied patients (2.7%) acquired 26 microbiologically documented nosocomial infections after off-pump coronary artery bypass grafting. Eight of 782 studied patients had pneumonia (1.02%), 7 of 782 (0.90%) had bacteremia, 4 of 782 (0.51%) had superficial wound infection at the sternotomy site, 4 of 782 (0.51%) had urinary tract infection, 2 of 782 (0.26%) had mediastinitis, and 1 of 782 (0.13%) had pressure sore infection. Twenty-one infections were monomicrobial, whereas 5 were polymicrobial. All polymicrobial infections were wound infections. There was a statistically significant difference in mortality between patients with and without nosocomial infection (23.8% vs 1.2%, P < .001). Clinical response of the infection to the treatment administered was observed in 21 of 26 episodes (80.8%) in 21 patients. A backward stepwise multivariable logistic regression model showed that independent risk factors (P < .05) associated with development of microbiologically documented nosocomial infection were arterial hypertension, previous vascular surgery, urgent operation, postoperative atrial fibrillation, number of inotropes used during and after operation, transfusion of fresh-frozen plasma during the intensive care unit stay, and intensive care unit stay until development of infection. CONCLUSION: Nosocomial infection after off-pump coronary artery bypass grafting is an uncommon but potentially life-threatening complication. The identification of independent risk factors, including arterial hypertension, associated with development of postoperative infection may help in the development of clinical strategies for the prevention, early diagnosis, and treatment of these infections.

External reshaping of the left ventricle in off-pump surgery.

BACKGROUND: : Dyskinetic areas of the lateral and inferior left ventricular (LV) wall are frequently encountered in patients with coronary artery disease. In clinical practice, all of the techniques described for the restoration of shape and function of the LV require cardiopulmonary bypass. A new technique of LV external reshaping that aims to obtain a near-normal ventricular conical shape is described. This technique is performed during an off-pump coronary artery bypass graft (CABG) operation. It is used mainly on the inferior and lateral walls of the ventricle, but also on the anterolateral wall when warranted. This technique can be considered an alternative to classic aneurysmectomy in high-risk cases. METHODS: : All patients underwent total arterial revascularization without aortic manipulation. Intraoperative transesophageal echocardiography was used in all cases to define the dilated akinetic/dyskinetic area. This area was effectively plicated using interrupted mattress sutures reinforced with Teflon felt or pericardial strips. This technique allows near normalization of the geometry of the ventricle and LV end-diastolic volume reduction. In cases of preexisting mitral regurgitation (MR), a reduction of the MR was observed after lateral wall restoration. From September 2002 to April 2005, the external reshaping technique was applied on 56 cases among 949 off-pump CABG cases (5.9%). A detailed transthoracic echocardiogram was obtained preoperatively. The mean ejection fraction of all enrolled patients was 31.2 ± 7%. The location of the plication was: lateral wall in 22, inferior wall in 16, and anterolateral wall in 18. The average number of coronary anastomoses was 2.6. Twelve patients were found to have 2-3+ MR. All patients were followed up during a period of 35 months. RESULTS: : One patient died due to severe right ventricular dysfunction. Seven patients developed atrial fibrillation, and one had ventricular tachycardia. During the follow-up period, we observed a reduction of left ventricular end-diastolic diameter and a parallel augmentation of ejection fraction (mean 42.2 ± 4%). The ventricular cavity's architecture was normalized. Among the 12 patients with MR, an improvement of regurgitation was noted in 10 (from 2-3+ to 1-2+). One patient died during the follow-up period, and 1 patient required reoperation due to persistent severe MR. CONCLUSIONS: : The external reshaping of the LV during beating heart surgery is technically feasible, has promising results, and can be performed without major complications.

Effusive-constrictive calcific pericarditis associated with Streptococcus salivarius. Case report and review of the literature.

We report the case of a 40-year-old patient presenting with a 6-month history of dyspnea and edema, with significant worsening of his clinical manifestations for the 2 weeks before admission to our department. During this 14-day preadmission period, continuous positive airway pressure (CPAP) was prescribed elsewhere for management of a working diagnosis of obstructive sleep apnea. The patient presented to us hemodynamically compromised. Management of the patient included emergency cardiac surgery for tamponade caused by effusive-constrictive, calcific pericarditis in addition to antimicrobial treatment as a result of the growth of Streptococcus salivarius from the pericardial fluid. This is the first report in the literature of association of this microorganism with pericarditis. The use of CPAP made the patient's symptoms worse as a result of an increase of the intrathoracic pressure, which was a pathophysiological mechanism, added to the interference of the localized pericardial effusion and the effect of the pericardial constriction. In an era of rapidly increasing use of CPAP systems, clinicians should be aware of their possible detrimental effects on patients with some types of cardiopulmonary diseases.

A new pattern for using both thoracic arteries to revascularize the entire heart: the pi-graft.

We present a complex graft for total arterial revascularization based on bilateral skeletonized internal thoracic arteries (ITA). The lower two-thirds of the free right ITA is anastomosed to the proximal segment of the left in situ ITA using the T-graft technique (Tector-Barner-Calafiore). The free, transected distal part of the left ITA is then anastomosed end-to-side on free right ITA (T-on-T anastomosis). In addition, the technique may use another graft extending the proximal third of the in situ right ITA with the free radial artery for right-sided revascularization. The entire operation can be performed off-pump to avoid any procedure on the ascending aorta.