Clinical evaluation of the eSVS Mesh: First-in-Man trial outcomes.

In coronary artery bypass graft surgery, saphenous vein graft (SVG) patency is much lower than that of the internal mammary artery (IMA). To address this problem, an external support device, the eSVS Mesh was developed. A prospective randomized First-in-Man feasibility trial was conducted in 90 patients after institutional ethics committee approval at seven international centers. The left IMA was used to bypass the anterior descending artery. A mesh-supported (treated) saphenous vein was randomized to either the right or the circumflex coronary system, and an unsupported (control) vein was grafted to the opposing territory. Device diameters available for use were 3.0, 3.5, 4.0, and 4.5 mm. Primary end-points were 30 day adverse cardiac and cerebral events and angiographic patency at 9-12 months. Eighty-five of 90 patients returned for 30 day clinical follow-up (94%). Five patients refused to return, but by telephone contacts were asymptomatic. There was one late noncardiac death and 73 patients returned for angiography (82%), thus 12 additional patients were lost to follow-up at 1 year. Overall patency rate was 49% for the treated versus 81% for controls (p < 0.001). Subset analysis revealed significantly lower patency at one center and with use of the 3.0 mm device (p < 0.05). Removing these data, patency was 72% vs. 81% (p = NS). Sternal wound infection was higher than expected at 5.0%, but this was center specific. The eSVS Mesh is safe, but at up to 1 year, patency is equivalent to untreated vein grafts after removal of outlying data. This study provides insight into operative events and parameters that may optimize outcomes and point to potential improvements in the external SVG support device. Furthermore, longer term studies are pending.

Computerized tomographic angiography in patients having eSVS Mesh(R) supported coronary saphenous vein grafts: intermediate term results.

BACKGROUND: The Saphenous Vein (SVG) is used in over 80% of coronary artery bypass procedures (CABG) and SVG patency is the Achilles heel of CABG. To address this issue, the eSVS Mesh(R), an external Nitinol knitted mesh, fitted like a sleeve over the vein graft preventing over expansion in the high pressure arterial system, has been introduced to improve disease management. Patency data is limited. The objective of this retrospective study is to report patency rates (>3 months) in patients having external mesh support as part of CABG. METHODS: From October 25, 2010 through February 13, 2012, 21 patients had external mesh support of SVG grafts in addition to internal thoracic artery grafting to the Anterior Descending artery. Patients were invited to return for patency evaluation using Computerized Tomographic angiography (CTA) an average of 7.2 months post-operative (R = 3-14 months). RESULTS: 21 male patients (age 57+/- 9 years) underwent on-pump surgery. The eSVS Mesh was successfully placed on all SVGs. All grafts were determined patent intra-operative by transit time Doppler measurement and there were no operative revisions. There was no operative mortality. 12 of the 21 contacted patients returned for CTA, 8 non-returning patients contacted were alive and asymptomatic but refused to return due to travel restrictions or cost. One patient was lost to follow up. 11 returning patients underwent CTA. One patient was excluded (asymptomatic) due to elevated creatinine. Of the 23 anastomoses in 11 patients(Average: 2.09 grafts/patient) using SVG available for examination, 21 were patent (92%). CONCLUSIONS: In this retrospective non-randomized experience, the external mesh supported grafts displayed excellent intermediate patency.

Influence of prosthesis type on long-term survival after re-replacement of aortic valve prosthesis.

BACKGROUND: The purpose of this study is to examine the influence of the prosthesis type on early mortality and long-term survival after re-replacement of aortic valve prosthesis, especially in patients over 60 years old. METHODS: Late outcome of 223 patients who underwent a reoperation on the aortic valve and received a mechanical (mechanical group) or biological (biological group) heart valve prosthesis at a single institution were analyzed for survival and major valve-related complications, including structural valve deterioration, thromboembolism, hemorrhage, further reoperation, and valve-related mortality. RESULTS: Preoperative New York Heart Association class IV (P = 0.001), emergency procedure (P = 0.002), and endocarditis (P = 0.025) were significant risk factors for 30-day mortality rates, which were 8.4 % and 12.5 %, respectively (mechanical versus biological group, P = 0.361). A subanalysis of elective patients revealed a low risk of 30-day mortality of 2.4 % and 1.8 %, respectively. Event-free survival was comparable at 5 years (73.9% ± 3.6% versus 70.5% ± 6.5%, mechanical versus biological group) and 10 year (49.7% ± 5.0% versus 35.3% ± 9.8%, mechanical versus biological group). In a propensity-matched subanalysis, survival and event-free survival were comparable at 5 and 10 years in both groups. CONCLUSION: The type of aortic valve prosthesis did not affect early outcome and late survival in patients who underwent valve replacement, and therefore, the current strategy favoring a biological aortic valve prosthesis for patients aged over 60 years in first-time operations could also be applied in re-replacement.

Aortic root and ascending aortic replacement.

The Ross procedure is occasionally favoured in young adults, with the implantation of a mechanical conduit remaining a competing option when simultaneous replacement of the ascending aorta is indicated. Eighteen patients with replacement of the ascending aorta, in addition to the Ross procedure (Ross), and 20 patients with a mechanical composite graft (composite) were compared retrospectively. The Short Form Health Survey (SF36) was used to assess quality of life (QoL). There was one death due to ischemic heart disease (composite), and one reoperation due to progressive autograft regurgitation (Ross). Autografts had pressure gradients of 3.1 +/- 1.9 mmHg (versus 10.8 +/- 2.7 mmHg composite; P < 0.001), and 7 autografts showed mild regurgitation. LV mass and global LV function were comparable in both groups (mean EF, 65.5% in Ross versus 61.6 +/- 10.4% in composite, P = NS). Four allografts in a pulmonary position had mild regurgitation (Ross). Two allografts had mild to moderate, and one had moderate pressure gradients (mean, 14.4 mmHg). Patients in the composite group had higher SF36 scores indicating superior QoL. No major bleeding was noted throughout the follow-up period. Despite pre-OP diminished LV function, similar follow-up values and, surprisingly, a higher QoL outcome, favoured the implantation of mechanical conduits in our group. These results warrant further evaluation in larger patient cohorts.

Factors affecting post minimally invasive direct coronary artery bypass grafting incidence of myocardial infarction, percutaneous transluminal coronary angioplasty, coronary artery bypass grafting and mortality of cardiac origin.

In the present study we identify parameters which influence the incidence of myocardial infarction (MI), need for percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG) and cardiac mortality after minimal invasive coronary artery bypass grafting (MIDCABG). With a mean follow-up of 30+/-11.2 months, 390 patients were assessed with Wald test-corrected chi(2) analysis to identify preoperative factors which correlate with a higher incidence of post-MIDCABG MI, PCI, CABG and mortality from cardiac causes. We found an increased incidence of postoperative MI in patients with 2-vessel (8.7%) and 3-vessel (7.7%) vs. 1.3% 1-vessel coronary artery disease (CAD) (P=0.023), and in patients with preceding cardiac procedure (CABG and PCI: 8.4% vs. 2.0% without, P=0.023). Also diabetes was associated with higher post-MIDCABG frequency of MI (P=0.035). Severity of angina was associated with lesser post-MIDCAB-PCI (P=0.011) while preceding CABG predicted a higher incidence (P=0.012). Preoperative low ejection fraction (EF) (multivariate, P<0.001), preoperative MI (P=0.007) and extent of CAD (P=0.001) were associated with a higher post-MIDCABG mortality. None of the parameters correlated with subsequent CABG MIDCABG. The extent and history of CAD, history of cardiac interventions and low EF seem to influence the outcome adversely and should be considered deciding pro or against the MIDCAB-option.

Consequences of incomplete repair of acute type A aortic dissection.

During emergency repair of acute Stanford type A aortic dissections, surgical compromises in the form of incomplete arch replacement are made due to the unstable condition of the patient and safety issues of the performing team. We report a case of delayed reoperation after previous incomplete surgery for acute type A aortic dissection in a young patient with Marfan's syndrome. He presented again with repetitive chest pain five years after initial surgical treatment. Extensive aneurysmal dilatation of the aorta and remaining dissection led to the decision to replace the ascending aorta and the aortic arch. After a good progress during the first days after surgery, the patient died due to a ruptured thoraco-abdominal aneurysm on the fifth postoperative day. Extensive surgical reconstruction including aortic arch replacement should be considered in patients with Marfan's syndrome who present with aortic dissections type A to avoid unnecessary reoperations and their complications.

MRI-based safety evaluation of the ventrica magnetic coronary anastomotic system.

The Ventrica Magnetic Vascular Positioner system is a novel automatic anastomotic coupling device for distal coronary artery anastomosis. There is concern that enormous magnetic fields may negatively affect graft anastomosis or coronary artery blood flow, or that they may lead to disconnection of the magnetic ports. Forty-five domestic swine (26.6 +/- 5.9 kg) underwent magnetic resonance imaging after a single Ventrica anastomosis of the left internal mammary artery to the left anterior descending artery. Group A (n = 15) underwent magnetic resonance imaging immediately after surgery, group B (n = 15) was studied after 1 week, and group C (n = 15) after 2 weeks. The animals were sacrificed and the anastomotic sites were examined. All animals survived the imaging procedure. Mean imaging time was 25 +/- 6 min. Although imaging artifacts occurred in the area surrounding the Ventrica port, there were no disconnections or electrocardiographic signs of ischemia during the study period. Upon sacrifice, all anastomoses were patent without alterations in the alignment of the magnetic components. Clinically relevant tests such as cranial magnetic resonance imaging may be safe after use of the Ventrica system for coronary artery revascularization.

Iatrogenic type A dissection after attempted stenting of a descending aortic aneurysm.

This case demonstrates an iatrogenic acute retrograde type A dissection of the aortic arch and ascending aorta during elective endovascular stenting of a proximal descending aortic aneurysm. This devastating complication necessitated emergent surgery with unfavorable postoperative outcome. Other than the known causes, the described retrograde type A dissection resulted from guidewire manipulation and iatrogenic creation of a false lumen, which was erroneously dilated and stented.

Creatine kinase isoenzyme MB relative index as predictor of mortality on extracorporeal membrane oxygenation support for postcardiotomy cardiogenic shock in adult patients.

OBJECTIVE: Extracorporeal membrane oxygenation (ECMO) has been used as initial, biventricular circulatory support for patients with severe postcardiotomy cardiogenic shock (PCS). Due to its aggressiveness and limited weaning quote, concerns have been raised about maintenance of ECMO support regarding duration. However, it is frequently hazardous for physicians to make an individualized decision, whether and when discontinuation of ECMO support should be considered. We tried to find measurable values during ECMO support that could predict the patient mortality on ECMO support. METHODS: During a 9-year period, 32 patients (mean age 55.4+/-11.9; ranging from 30 to 75 years) with ECMO support for postcardiotomy cardiogenic shock were included in this study. RESULTS: Eighteen patients died without weaning (group I, 56.25%), while 14 patients could be weaned off the ECMO support (group II, 43.75%). In the group II, six patients (18.75%) died later in the postoperative course and eight patients (25%) survived to be discharged from hospital. The overall survival of all 32 patients at 30 days was 31.25% (n=10). At a follow-up period of 3.88+/-1.58 years, the overall survival rate was 12.5% (n=4). Mean duration of ECMO support was 2.7+/-1.7 days. The following variables were significantly different between the two groups: blood lactate level and the level of MB isoenzyme of creatine kinase (CK-MB) 48 h after ECMO initiation (p<0.01, p=0.001) as well as the CK-MB relative index as the ratio of CK-MB to total CK (p<0.001). Logistic regression identified that only the CK-MB relative index 48 h after ECMO initiation was associated with mortality on ECMO support (p=0.011, odds ratio=1.219, 95% confidence interval: 1.046-1.421). CONCLUSION: For adult non-transplantation patients with postcardiotomy cardiogenic shock, the CK-MB relative index 48 h after ECMO initiation can be a predictor of mortality on ECMO support. This might be a useful tool for considering a patient either for discontinuation of ECMO support or further treatment.

Short moderate hypothermic circulatory arrest without any adjunctive cerebral protection for surgical repair of the ascending aorta extending into the proximal aortic arch: is it safe?

INTRODUCTION: We have been using only moderate hypothermic circulatory arrest (HCA) for patients with ascending aortic aneurysms extending into the proximal aortic arch if the distal anastomoses seem to be simple and easy. The aim of this study is to evaluate the early and midterm results of the use of moderate HCA without any adjunctive cerebral protection in such patients. METHODS: Between October 2000 and March 2005, 23 patients with an age range of 39 to 77 years (mean, 59.7 +/- 12.2 years) received surgical repair of the ascending aorta extending into the proximal aortic arch using HCA without any adjunctive cerebral protection. Mean circulatory arrest time was 7.5 +/- 2.0 minutes (range, 2-13 minutes), and mean core temperature at induction of the circulatory arrest was 26.7 +/- 1.4 degrees C (range, 24-30 degrees C). RESULTS: Operative mortality was 4.3% (1/23) due to unknown cause after successful extubation. Temporary neurological dysfunction was observed in only 1 patient (4.3%), and no persistent neurologic event was observed in any of the patients. One patient died 3 months after the operation due to a mediastinitis. No other cardiac or neurologic event was observed in the 21 surviving patients. CONCLUSION: Our results suggest that moderate HCA at 26 degrees C to 28 degrees C without any adjunctive cerebral protection within 10 minutes is safe in selected patients.

Cerebral microembolization during antegrade selective cerebral perfusion.

BACKGROUND: This study quantified the number of intraoperative microemboli in patients undergoing aortic arch surgery using selective cerebral perfusion (SCP) in comparison with those in patients undergoing ascending aortic replacement without circulatory arrest and SCP. METHODS: A transcranial Doppler monitoring of the medial cerebral artery was performed in 15 patients undergoing proximal arch replacement with SCP (SCP group) and 15 patients undergoing replacement of the ascending aorta (control group). RESULTS: There was no significant difference in the high-intensity transient signal counts between the SCP group and the control group at any phase. In the SCP group, 4.8% of microemboli occurred during cross-clamping, and only 0.6% occurred during SCP. In the control group, 4.6% occurred during cross-clamping. Most microemboli occurred after removing the cross-clamps in both groups; 92.2% in the SCP group and 92.1% in the control group. CONCLUSIONS: The present study demonstrated that outbreak frequency of microemboli during SCP was very low, and thus implies that the risk of embolic event that may be caused by SCP is very low.

Anastomotic obstruction after magnetic vascular coupling after minimally invasive direct coronary artery bypass grafting.

We report a 61-year-old man who required reoperation 8 months after minimally invasive direct coronary artery bypass grafting after magnetic vascular coupling due to a symptomatic subtotal obstruction at the anastomotic site. It was also determined that the patient had been noncompliant in following the prescribed postoperative antiplatelet therapy.

Glycine application and right heart function in a porcine heart transplantation model.

Glycine reduces ischemia-reperfusion injury after experimental liver transplantation. We hypothesized that glycine might also protect right heart function in an isovolumic cardiac transplantation model. In six domestic donor pigs 150 ml of a 300 mmol L-glycine solution were administered intravenously. The hearts were then arrested with histidine-tryptophan-ketoglutarate solution. Animals without prior glycine infusion served as controls (n = 6). After 4 h of ischemia, hearts were transplanted into recipients. An isovolumic model was used in which the right ventricular (RV) volume was controlled in vivo using an intracavitary high-compliance balloon. After 1 and 2 h of reperfusion the RV balloon volume was gradually increased and the developed pressures were recorded (P(developed) = P(systolic) - P(diastolic)). Right ventricular failure was defined as a decrease in developed intracavitary pressure. Glycine hearts could be loaded with a significantly increased volume after 1 h (glycine: 53 +/- 13.7 ml vs. control: 32 +/- 11.7 ml; P = 0.015) and after 2 h (67 +/- 18.6 ml vs. 43 +/- 8.2 ml; P = 0.018). Maximal RV developed pressures were not significantly different between groups. Postischemic RV end-diastolic compliance was significantly higher in glycine-treated animals (P = 0.04). Glycine protects early postischemic RV compliance, but has no important influence on maximal developed pressures.

Allopurinol/uricase and ibuprofen enhance engraftment of cardiomyocyte-enriched human embryonic stem cells and improve cardiac function following myocardial injury.

OBJECTIVE: A major limitation of stem cell transfer is early donor-cell death. Here, we seek to enhance myocardial repair following injury through transplantation of cardiomyocyte-enriched human embryonic stem cells (hESC) and recipient treatment with cytoprotective (allopurinol+uricase) and anti-inflammatory (ibuprofen) agents. METHODS: We injected 10(6) (15% hESC-derived cardiomyocytes) green fluorescent protein (GFP+) hESC in the infarcted area following left anterior descending artery (LAD)-ligation in SCID-beige mice. In Group I, 1.6 mg allopurinol and 0.2 mg of uricase were injected i.p. for 3 days prior to cell transplantation. In Group II, 0.35 mg/ml of ibuprofen were added to the drinking water before and after cell implantation. In Group III, the LAD was ligated and allopurinol/uricase was administered without cell treatment. In Group IV, ibuprofen was added to the drinking water and the LAD was ligated without additional cell treatment. In Group V, only cells were transplanted. Group VI involved infarcted controls and Group VII involved sham-operated mice (all groups: n=5). We evaluated heart function (ejection fraction (EF)) by MRI (4.7 T) 3 weeks later. The hearts were harvested for histology. RESULTS: Differentiated hESC formed clusters and expressed alpha-sarcomeric actin and Connexin 43. Cell treatment improved heart function, which was best in the ibuprofen- and allopurinol-treated groups (+cell transfer), compared to the infarcted controls [EF: Group I: 76.6+/-8.6%, Group II: 78.6+/-7.3%, Group III: 58.1+/-5.7%, Group IV: 53.9+/-5.2%, Group V: 57.7+/-7.5%, Group VI: 43.5+/-4.3%, and Group VII: 66.3+/-7.8%]. We did not observe tumors in any group. CONCLUSIONS: Allopurinol/uricase and ibuprofen enhance differentiated hESC-engraftment and myocardial restoration following transplantation into the injured heart.

Preliminary experience with the mini-extracorporeal circulation system (Medtronic resting heart system).

A compact cardiopulmonary bypass (CPB) utilized by closed circuit system with minimized priming volume can be a solution to reduce adverse effects of CPB, and the Resting Heart System (RHS; Medtronic, Inc, Minneapolis, MN, USA) is the newest one on the market. We performed CABG with RHS in 10 patients, and report here our preliminary experiences with RHS in comparison with conventional CPB. Twenty patients who underwent isolated CABG were randomized into two groups; RHS group (n=10) with the use of RHS and Conventional group (n=10) with the use of a conventional CPB. There were no significant differences of preoperative patient characteristics in both groups. The mean number of grafts was 2.7+/-0.6 and 2.7+/-0.8 (P=0.38), the mean aortic clamp was 32+/-11 and 35+/-11 min (P=0.35), and CPB times were 68+/-25 and 72+/-24 min (P=0.82) in RHS and Conventional group, respectively. All patients but one had no complications and survived in both groups. One patient in RHS group died suddenly on the 5th postoperative day after uneventful postoperative course. Postoperative leukocyte count at 6 h after the operation and value of the C-reactive protein were 11200+/-2310 and 13300+/-3990/mm(3) (P=0.10) and 44.4+/-9.7 and 65.3+/-18.5 mg/l (P=0.045) in RHS and Conventional group, respectively. CABG operations could be safely performed using the RHS with a comfort level similar to standard CPB.

Long-term physical activity and neurologic function after harvesting of the radial artery as T-graft or free graft in coronary revascularization.

BACKGROUND: Radial artery grafts in coronary revascularization are frequently used, either as a T-graft or as a free radial graft such as a saphenous venous graft. Besides the neurologic function of the hand after radial artery harvesting, which is questioned especially in the long-term perspective, no data on patients' lifestyle are available in this special cohort. Therefore we focused on both the patients' neurologic function as well as level of physical activity, along with their body mass index and smoking habits in this prospective, long-term study. METHODS: Two hundred eleven patients (187 males; 64 +/- 8 years; mean Canadian coronary scale, 2.4 +/- 0.7; ejection fraction, 59 +/- 15%) were enrolled and scheduled for elective radial artery harvesting in an open conventional technique. Follow-up of 26 +/- 5 months (range, 13 to 37 months) was performed by a direct telephone interview with patients, which was 100% complete. The majority of radial arteries were used in the T-graft technique (73.9%), 24.2% were used as a free graft, and 1.4% as a jump graft. RESULTS: One hundred sixty-five patients (78.2%) did not complain of any neurologic deficit at all. Numbness was distributed among the thumb (5.2%), the wrist (4.3%), and the incision site (3.3%). Hyposensitivity was predominantly at the wrist, followed by the thumb. Pain was distributed at the wrist (1.9%) and the thumb (1.5%). Aggravated sense of cold at the donor hand was evident in 11 patients (5.2%). No patient was compromised in their daily activities, such as piano playing or writing. Subjective well being improved in 147 patients (69.7%), was unchanged in 39 patients (18.5%), and was worse in 11 patients (5.3%) after radial artery harvesting. The mean Canadian coronary scale class improved significantly (1.3 +/- 0.6; p < 0.05). There were patients (44.5%) who performed no sports activity after the procedure and patients (11.8%) who performed sports every day of the week. There were patients (80.1%) who did not participate in heart sport groups, with only 27 patients (12.8%) participating in such heart sport groups once a week. One hundred seventy-one patients (81.0%) attended a cardiac rehabilitation program after the procedure. Body mass index did not change at all. There were patients (29%) who stopped smoking as of the procedure, whereas 10% of patients were active smokers 25 months after the procedure. CONCLUSIONS: Radial artery harvesting is associated with a minor number of neurologic complications such as numbness and hyposensitivity after a conventional pedicled harvesting technique without any compromise on patients' daily activities. Further emphasis has to be taken in the promotion of lifestyle changes after coronary revascularization. About half of the patients did not perform any regular physical activity 2 years after surgery; mean body mass index did not change; and nearly 10% continued to smoke.