Indocyanine green clearance as an outcome prediction tool in cardiac surgery: a prospective study.

PURPOSE: To evaluate the role of plasma disappearance rate of indocyanine green (PDR-ICG) as an outcome prediction tool in cardiac surgery. PATIENTS AND METHODS: One hundred ninety patients undergoing coronary artery bypass grafting, valve surgery or combined procedures were enrolled. PDR-ICG measurements along with standard lab values were performed preoperative and on postoperative days 1, 2, and on discharge from the intensive care unit. Adverse outcomes were defined as prolonged length of stay in the intensive care unit and/or mortality. Two groups were defined according to length of stay in the intensive care unit (≤ 3 days vs >3 days). RESULTS: PDR-ICG values differed significantly for all time points between the groups. In a multivariate model, in patients over 65 years with a EuroSCORE below 8.5, a preoperative PDR-ICG value below 12.85%/min was the strongest independent predictor for prolonged intensive care unit stay (>3 days). A preoperative PDR-ICG value below 8.2%/min was the strongest independent predictor for mortality in a multivariate analysis including age, cardiac function, and EuroSCORE. CONCLUSIONS: In addition to the established scores, PDR-ICG may provide valuable information for the assessment of perioperative morbidity and mortality in cardiac surgery. Pre- and early postoperative measurements may help to identify patients at risk for developing perioperative complications.

Deep pericardial traction suture versus vacuum-assisted apical suction to expose the posterior wall of the heart in off-pump coronary artery bypass: a prospective, randomized study.

BACKGROUND: Displacement of the heart to expose the posterior vessels during off-pump coronary artery bypass (OPCAB) may cause hemodynamic instability. Deep pericardial traction suture (DPTS) and vacuum-assisted apical suction (VAS) with the Starfish positioning device help to provide good exposure without relevant hemodynamic changes. Our aim was to compare these two methods in patients undergoing multivessel OPCAB. METHODS: We prospectively randomized 20 patients undergoing multivessel OPCAB to the use of VAS or DPTS. The Octopus device was used in both groups to stabilize the target vessel. Hemodynamic parameters, including venous oxygen content (SvO(2)), cardiac index (CI), central venous pressure (CVP), mean arterial pressure (MAP), pulmonary artery pressure (PAP), and pulmonary capillary wedge pressure (PCWP), were measured before grafting (baseline), after heart positioning, and during performance of peripheral anastomoses. RESULTS: Perioperative data for the two groups were similar. During exposure of the lateral wall, there were fewer hemodynamic changes in the DPTS group (increase in CVP) than in the VAS group (increases in CVP, PAP, and PCWP); the CVP was significantly higher in the DPTS group (P < .05). During exposure of the posterior wall, significant hemodynamic changes occurred only in the DPTS group (increase in PCWP). Values for all other parameters were similar, including anastomosis time, graft flow, postoperative myocardial enzymes, and inotropic support. CONCLUSIONS: Heart positioning during OPCAB with either VAS or DPTS is a safe and effective maneuver for exposure of coronary arteries. In our study, the use of the VAS device produced less hemodynamic impairment during exposure of the lateral and posterior walls.

An uncommon cause of myocardial ischemia after coronary artery bypass grafting: "the dangerous drainage".

The most common causes of myocardial ischemia and myocardial infarction early after coronary artery bypass grafting surgery are early graft occlusion/thrombosis or occlusion/ thrombosis of coronary arteries due to advanced coronary heart disease. We describe a case of postoperative myocardial ischemia due to an uncommon and quickly reversible cause: mechanical compression of a vein graft by a 19F flexible silicone mediastinal drainage tube.

Interrupted nitinol U-Clips versus standard running suture for the central arterial T-graft anastomosis: a prospective randomized study.

OBJECTIVES: Studies carried out to date suggest that the interrupted suture technique using U-Clips for anastomoses in coronary surgery may be superior to the standard running polypropylene suture. The purpose of this study was to compare safety and effectiveness of a central T-graft anastomosis constructed with the left internal thoracic artery (LITA) in situ (to the left anterior descending (LAD)) in which the free right internal thoracic artery (to the circumflex branch of the right coronary artery (RCX)) was implanted (RITA-to-LITA) using either self-closing nitinol U-Clips or simple continuous suture. We hypothesized that internal thoracic arteries could adapt their diameter to the blood flow. METHODS: Thirty patients underwent total arterial revascularization using a T-graft constructed with free LITA in situ to LAD in which the free RITA to the circumflex artery was implanted (central T-graft anastomosis). In all cases, free RITA was used as a sequential graft with two peripheral anastomoses. Patients were randomly assigned to two groups: in group A (n=15), central T-graft anastomosis was performed using a standard 8/0 polypropylene running suture. In group B (n=15), central T-graft anastomosis was performed using U-Clips. Intra-operative transit time flow measurements were recorded. Patency control was performed in 30 patients 2 weeks and 6 months postoperatively, using 64-slice computed tomography (CT) angiography. The diameter of the LITA was measured proximal and distal and the diameter of the RITA distal to the central T-graft anastomosis. RESULTS: Perioperative results were similar in the two groups (P=ns). Intra-operative transit time flow measurement showed patent grafts in all patients. There were no hospital deaths. Two weeks postoperatively, all grafts were patent. At 6-month follow-up, one RITA and one LITA (both in group B) were closed distal to the central T-graft anastomosis. There was no death and no re-intervention during follow-up. Statistical analysis showed no significant changes in graft diameters after 2 weeks and 6 months in both groups. CONCLUSIONS: The U-Clip anastomosis technique is in our experience safe but not superior to the standard running suture using polypropylene material. Remodeling of the ITA grafts close to the central T-graft anastomosis was neither observed for the standard running suture nor for the U-Clip anastomoses.

Myocardial transfection of hypoxia inducible factor-1alpha via an adenoviral vector during coronary artery bypass grafting. - A multicenter phase I and safety study -.

BACKGROUND: Increasing numbers of patients with advanced coronary artery disease have limited options for percutaneous and/or surgical revascularization. A prospective, randomized, phase I clinical multicenter trial was performed to assess the feasibility and safety of delivering a pro-angiogenic transcription factor termed "hypoxia inducible factor-1alpha", delivered to ischemic cardiac muscle via a type 2 adenoviral (Ad2HIF) vector. METHODS AND RESULTS: The 13 patients were included under the following criteria: 1 hypoperfused area of viable ventricular muscle without options for revascularization and left ventricular ejection fraction > or =30%. After coronary artery bypass grafting was completed, 10 injections of the study drug (n=10), in 3 escalating doses up to 1 x 10(11) viral particles or saline (n=3) as a placebo control, were injected intramyocardially. After completion of the 1-year follow-up, all patients had uncomplicated postoperative courses, are alive and feeling well; 1 patient had a self-limited run of tachycardia postoperatively and at 6 months, 1 patient developed recurrent angina. Positron emission tomography perfusion analysis revealed improvement in the Ad2HIF injected areas in selected patients. CONCLUSIONS: These data support the feasibility and preliminary safety of adenoviral transfection with Ad2HIF in regions of viable myocardium. Additional studies will be required to determine the efficacy and safety of Ad2HIF.

Off-pump coronary artery bypass in a patient with congenital absence of the left pericardium and an extremely left-rotated heart.

Congenital anomalies of the pericardium are extremely rare and often difficult to diagnose. We describe a 66-year-old woman presenting with multivessel coronary artery disease and right heart insufficiency complicated by an extremely left-rotated heart due to a congenital absence of left pericardium. A multidetector row computerized tomographic study was performed to evaluate the torsion of the heart as well as the physical relationship between the left internal thoracic artery and the left coronary system. Off-pump coronary surgery was scheduled. Both the operative and postoperative courses were uneventful and the patient was discharged after 11 days.

Minimizing cardiac surgery risks in a Hepatitis C patient: Changing surgical strategy after evaluation by modern imaging technologies.

Minimizing operative risks for the surgical team in infectious patients is crucial. We report on a patient suffering from Hepatitis C undergoing re-operative aortic valve and ascending aorta replacement for aortic aneurysm and paravalvular leakage due to recurrent endocarditis of a Smeloff-Cutter aortic ball prosthesis. Preoperative multi-slice computed tomography and real-time three-dimensional echocardiography proved helpful in changing operative strategy by detecting a previously unknown aortic aneurysm, assessing its extent, and demonstrating the close proximity of the right coronary artery, right ventricle, and the aortic aneurysm to the sternum. Thus, cardiopulmonary bypass was instituted via the femoral vessels, instead of conventionally. Location, morphology, and extent of the paravalvular defect could also be assessed.

Tentacles: a novel device for exposing the heart for the insertion of left apical assist device cannulae.

BACKGROUND: The implantation of ventricular assist devices is a well-established procedure for the treatment of imminent heart failure. The exact positioning of the left ventricular apical inflow cannula is crucial, because inflow restrictions might occur when the cannula is placed too close to the interventricular septum or a papillary muscle. We report a novel technique using the Tentacles 3-point fixation device for the exposure of the left ventricular apex during ventricular fibrillation under cardiopulmonary bypass. METHODS: We used the Tentacles, a device originally designed for positioning the heart during off-pump coronary artery bypass grafting, for implantation of a biventricular Berlin Heart Excor in a 64-year-old man. The procedure was successful and echocardiographic examinations documented the exact placement of the left ventricular cannula. RESULTS AND CONCLUSION: Our new technique ensures a very precise insertion of apical cannulae, because the left ventricular shape and filling are not impaired.

Off-pump coronary surgery for allograft vasculopathy 8 years after heart transplant.

Cardiac allograft vasculopathy is a severe complication after heart transplant, and is the major cause of death in patients surviving 1 year after transplant. We present a 59-year-old patient undergoing off-pump, coronary artery bypass surgery, 8 years after heart transplant. Owing to toxic liver disease, the lipid lowering therapy with statins had to be stopped 6 years after transplant, and coronary artery disease developed rapidly within 2 years. Off-pump, coronary bypass surgery was performed using a new, multisuction cardiac positioner; a disposable stabilizer; and a proximal seal system to avoid clamping of the aorta. The patient received 3 bypass grafts: the left internal thoracic artery; to the left anterior descending coronary artery; 1 saphenous vein graft to the marginal branch of the circumflex artery; and 1 saphenous vein graft to the right coronary artery. His postoperative course was uneventful.

Long-term results after ablation for long-standing atrial fibrillation concomitant to surgery for organic heart disease: is microwave energy reliable?

OBJECTIVE: Microwave ablation has been reported as efficient for the surgical treatment of long-standing atrial fibrillation. However, the influence of ablation lesions on long-term results is not known. METHODS: From August of 2000 to November of 2003, 41 patients underwent a left atrial endocardial microwave ablation procedure after a Cox-Maze-like lesion set for long-standing atrial fibrillation concomitant to surgery for valvular or coronary artery disease. Mitral valve surgery alone or combined was performed in 31 cases (75.6%). The mean diameter of the left atrium was 7.19 +/- 1.44 cm. The mean duration of preoperative atrial fibrillation was 4.7 +/- 3.6 years. Patient follow-up was conducted by means of direct clinical examination, electrocardiography, and transthoracic echocardiography. The mean follow-up was 5.37 +/- 0.91 years. RESULTS: Patient follow-up was achieved in 82% of cases (n = 28). Seven patients (17%) died during follow-up. Stroke was the cause of death in 1 patient with persistence of atrial fibrillation. Major complications occurred in 4 (14.3%) of the patients that were related to the persistence of atrial fibrillation. At 5 years follow-up, 39.3% of patients (11/28) were in sinus rhythm. Seventeen patients (60.7%) were in New York Heart Association classes I and II, and 11 patients (39.3%) were in New York Heart Association class III at the time of follow-up. CONCLUSION: In our experience, left atrial endocardial microwave ablation for long-standing atrial fibrillation after a Cox-Maze-like ablation lesion set during surgery for organic heart disease is not a reliable method of achieving long-term conversion to sinus rhythm.

Donor-specific HLA alloantibodies: long-term impact on cardiac allograft vasculopathy and mortality after heart transplant.

OBJECTIVES: The clinical significance of anti-HLA-alloantibodies remains controversial. Recent studies have linked development of donor-specific HLA-antibodies to chronic allograft rejection and graft loss after heart, kidney, and lung transplants. We investigated the clinical impact of donor-specific humoral alloreactivity during the follow-up of heart transplant recipients. PATIENTS AND METHODS: The sera of 213 heart transplant recipients were screened by enzyme-linked immunosorbent assay for HLA-antibody production. The antigen specificity of the detected HLA class I and class II antibodies was identified using a Luminex assay. Outcome variables were survival, cardiac allograft vasculopathy, and cellular rejection. RESULTS: The cumulative incidence of alloantibody formation was 23/213 patients (10.8%). The majority of detected alloantibodies were donor-specific for HLA class II. Mean follow-up at antibody measurements was 7 -/+ 4.9 years. Freedom from vasculopathy at 5 and 10 years was 77.9% and 26% in donor-specific HLA-antibody-positive patients compared with 84.6% and 65.2% in antibody-negative controls (P = .025). Freedom from treated, biopsy-proven rejection was 44.4% for donor-specific HLA-antibody-positive patients compared with 70.2% in the controls (P = .06). Multivariate analyses identified donor-specific HLA antibody positivity as an independent risk factor for vasculopathy. CONCLUSIONS: Our results demonstrate a strong correlation between the development of donor-specific HLA antibodies and adverse outcomes after heart transplant. Detection of donor-specific HLA antibodies might identify high-risk patients and offer an opportunity for early clinical intervention and modification of immunosuppression.

Three-dimensional printing creates models for surgical planning of aortic valve replacement after previous coronary bypass grafting.

PURPOSE: Resternotomy for aortic valve replacement in patients with previous coronary artery bypass grafting and an internal mammary artery graft may be a surgical problem. Thus, we are exploring the effect of using rapid prototyping techniques for surgical planning and intraoperative orientation during aortic valve replacement after previous coronary artery bypass grafting (CABG). DESCRIPTION: As a proof of concept, we studied a patient who had undergone CABG 5 years earlier. At that time the patient received a left internal mammary artery graft to the left anterior descending artery and a venous graft to the right coronary artery. Now the patient required aortic valve replacement due to symptomatic aortic valve stenosis. The left internal mammary artery bypass and the right coronary artery bypass were patent and showed good flow in the angiography. The patient was examined by 128-slice computed tomography. The image data were visualized and reconstructed. Afterwards, a replica showing the anatomic structures was fabricated using a rapid prototyping machine. EVALUATION: Using data derived from 128-slice computed tomography angiography linked to proprietary software, we were able to create three-dimensional reconstructions of the vascular anatomy after the previous CABG. The models were sterilized and taken to the operating theatre for orientation during the surgical procedure. CONCLUSIONS: Stereolithographic replicas are helpful for choosing treatment strategies in surgical planning and for intraoperative orientation during reoperations of patients with previous CABG.

Daptomycin for eradication of a systemic infection with a methicillin-resistant-Staphylococcus aureus in a biventricular assist device recipient.

The rate of infection in patients who require ventricular assist devices is estimated at more than 35%. Infections with multi-resistant organisms such as methicillin-resistant Staphylococcus aureus in ventricular assist device recipients are often difficult to treat and present a high mortality rate. Daptomycin is a new cyclic lipopeptide antibiotic, useful in gram-positive organisms resistant to standard treatment. We report a case of a 65-year-old man suffering from a dilatative cardiomyopathy and concomitant MRSA infection who received a biventricular assist device. The patient had MRSA sepsis develop resistant to conventional therapy, which was successfully treated with daptomycin.

Mid-term patency after magnetic coupling for distal bypass anastomosis in coronary surgery.

BACKGROUND: The magnetic vascular positioner (MVP), a device for distal bypass anastomosis in coronary surgery, was developed to allow a simple and rapid procedure and to improve graft patency. We analyze our mid-term results with this device. METHODS: Eighteen distal anastomoses were performed by using the MVP, and 18 with a hand-sewn technique were completed in 11 patients. The target arteries for the MVP anastomosis were the left anterior descending in 9 patients, a marginal branch in 4, a diagonal branch in 3, and right coronary artery in 2. The left internal thoracic artery was used as graft in 9 patients, saphenous vein in 6, right internal thoracic artery in 2, and radial artery in 1. RESULTS: Coronary angiography was performed at discharge and after a complete follow-up of 19 +/- 3.5 months. Patency at follow-up was 83.3% (15/18) for MVP anastomoses and 100% (18/18) for hand-sewn anastomoses. All occluded MVP anastomoses were performed with small-size devices. In one patient, a high-grade left main stenosis was overestimated. Competitive flow may be suspected in this case as a cause of graft occlusion. No deaths occurred during hospital stay or during follow-up. Freedom from reintervention was 100%. CONCLUSIONS: The MVP is the only mechanical connector for distal anastomoses applicable for all kind of grafts, for all coronary artery locations, and with both end-to-side and side-to-side technique. Mid-term patency of MVP anastomoses is acceptable but inferior to the patency of hand-sewn anastomoses. Occlusion of MVP supplied grafts may be produced by small device size.

34-year durability of a DeBakey Surgitool mechanical aortic valve prosthesis.

BACKGROUND: The DeBakey Surgitool mechanical aortic valve prosthesis was the first mechanical prosthetic valve in which pyrolitic carbon was used. This valve was on the market from 1969 to 1978 and approximately 3300 valves were implanted in this lapse worldwide. REPORT: We present a DeBakey Surgitool mechanical aortic valve prosthesis implanted in 1972, which has been functioning for almost 34 years and still presents a good performance. COMMENT: Spontaneous strut fractures associated with haemodynamic complications and death, even in asymptomatic patients, was the reason to withdraw this prosthetic valve from the market. However, a prophylactic replacement of DeBakey Surgitool valve was not indicated in our patient due to the excellent prosthesis compliance.

Miniaturized cardiopulmonary bypass in coronary artery bypass surgery: marginal impact on inflammation and coagulation but loss of safety margins.

PURPOSE: Inflammation and coagulation disturbances are common consequences of cardiopulmonary bypass (CPB). Recently, miniaturized closed CPB circuits without cardiotomy suction and venous reservoir have been proposed to reduce complication rates. We compared outcomes with conventional (CCPB) and miniaturized cardiopulmonary bypass (MCPB) after coronary artery bypass operations (CABG) with respect to inflammation and coagulation. DESCRIPTION: Thirty patients (23% female; aged 67.9 +/- 9.0 years) were prospectively randomly assigned to undergo isolated CABG with CCPB or MCPB. Conventional CPB had a pump prime of 1, 600 mL. Miniaturized CPB consisted of a centrifugal pump, arterial filter, heparinized tubing, and oxygenator with a priming volume of 800 mL. Shed blood was removed by a cell-saving device and reinfused. Measurements included interleukin (IL)-2 receptor, IL-6, IL-10, tumor necrosis factor receptor 55 and 75, C reactive protein, leukocyte differentiation, d-dimers, fibrinogen, and thrombocytes at six time points. EVALUATION: In both groups no major complication occurred. However, two dangerous air leaks occurred in the closed MCPB circuit, demonstrating the narrow safety margins. Operative handling was also more difficult owing to limitations in venting and fluid management. International normalized ratio (p = 0.03) and antithrombin III (p = 0.04) levels were elevated during CPB in the CCPB group, most likely owing to differences of the intraoperative anticoagulation management. Repeated measures analysis revealed that not a single parameter of inflammation or clinical outcome showed significant differences among groups. CONCLUSIONS: Use of a MCPB affected inflammation and coagulation variables only marginally and did not lead to clinical relevant changes as assessed by blood loss, need for blood products, and intensive care unit and clinical stays. However, safety margins for volume loss, air emboli, and weaning from CPB decrease, because of the closed MCPB circuit.

Hemodynamic and vascular effects of ventricular sourcing by stent-based ventricle to coronary artery bypass in patients with multivessel disease undergoing coronary artery bypass surgery.

BACKGROUND: The hemodynamic and vascular effects of ventricular sourcing by a stent-based (VSTENT, Percardia) left ventricle-to-coronary artery bypass were studied in a patient subgroup of the European multicenter ADVANTAGE study (ADjunctive treatment with the VCAB/VSTENT myocardial implANT system in coronary Artery bypass Graft patiEnts). METHODS AND RESULTS: Twelve patients who underwent VSTENT implantation in addition to coronary artery bypass surgery were studied up to 12 months after the procedure. The VSTENT was implanted distal to a hemodynamically relevant coronary artery stenosis. Coronary flow velocity was assessed at rest and during dobutamine stress. Intraoperative VSTENT implantation was successful in 11 of 12 patients. Early postoperative angiograms showed patent VSTENT in 8 of 11 patients, with predominantly systolic flow distal to the VSTENT. Coronary flow velocity reserve induced by dobutamine stress was 1.7+/-0.1 (P=0.006). VSTENT patency at 2- to 6-month follow-up was present in 5 of 11 patients, with concomitant VSTENT stenosis in 4 of those 5. In all patients, coronary flow velocity increased 3- to 4-fold proximal to the VSTENT, which was associated with a moderate degree of arterial remodeling. Except for target vessel reintervention (n=5), no other major adverse events were observed in 11 of 12 patients. One patient died on the second postoperative day, though the cause was probably not related to the VSTENT implantation. CONCLUSIONS: VSTENT implantation seems to be safe in the mid-term follow-up and leads to a predominantly systolic coronary flow pattern in the vessel supplied by the VSTENT, with a flow reserve similar or close to that seen with conventional bypass. VSTENT patency rate, however, was unacceptably low at 3- to 6-month follow-up and needs to be improved.

First clinical experience with the HEARTSTRING, a device for proximal anastomoses in coronary surgery.

PURPOSE: The HEARTSTRING is a device designed to enable the creation of a clampless hand-sewn proximal anastomosis. DESCRIPTION: Seventy-six patients who underwent myocardial revascularization had 113 proximal anastomoses created by the HEARTSTRING. Fifty-five procedures were performed on cardiopulmonary bypass and 21, off pump. EVALUATION: Of 114 intended proximal anastomoses, 113 (99.1%) were successfully performed using the HEARTSTRING. The conduits anastomosed proximal with support of the HEARTSTRING were in 92 cases saphenous veins and in 21 cases radial arteries. Mean time to perform a HEARTSTRING-supported anastomosis was 6.6 +/- 1.2 minutes. One patient (1.3%) died postoperatively; the death was not device related. In 1 additional patient (1.3%), a stroke most likely due to air embolism occurred. Forty-nine patients (64.5%) underwent a predischarge coronary angiography (n = 20) or a contrast multislice computed tomography (n = 29). Of 76 grafts with a HEARTSTRING-supported proximal anastomosis, 74 (97.4%) were patent in these 49 patients. CONCLUSIONS: Our initial clinical experience with the HEARTSTRING demonstrates safety, reliability, and ease of use. Side clamping of the ascending aorta can be avoided, potentially decreasing the incidence of neurologic complications.