Cardiac rehabilitation in a heart-failure patient using customized "cardiac support net" treatment: a case report.

At our hospital, we are conducting the "Clinical Study of a Patient-Specific Cardiac Support Net for Dilated Cardiomyopathy (jRCTs042180025)", a multi-facility clinical study of a customized cardiac support net (CSN). Here, we describe the cardiac rehabilitation (CR) of a heart failure (HF) patient after CSN treatment. The patient was a 65-year-old man who exhibited dilated cardiomyopathy (DCM) because of left ventricular non-compaction; his New York Heart Association status was class III. In November 2019, he received CSN treatment. The early CR program was adapted for this patient, and his postoperative course was uneventful. Functional measurements showed improved leg-muscle strength (before treatment: 61.4% BW; at discharge: 77.3% BW). During long-term follow-up, the patient's exercise tolerance increased, as shown by 6-minute walk distance (before treatment: 576 m; long-term follow-up: 600 m) and peak oxygen uptake (before treatment: 12.5 mL/kg/min; long-term follow-up: 13.3 mL/kg/min). In the 2 years since discharge, the patient has not been hospitalized for HF. This report is the first to show that the CSN can be used to perform a CR program in a DCM patient without significant functional decline.

Hypofibrinogenemia can be estimated by the predictive formula in aortic surgery.

OBJECTIVE: Aortic surgery often causes massive bleeding due to hypofibrinogenemia. Predicting hypofibrinogenemia is useful for developing a hemostasis strategy, including preparing for blood transfusion. We made a formula for predicting the serum fibrinogen level (SFL) at the termination of cardiopulmonary bypass (CPB) in aortic surgery and examined its validity. METHODS: We performed a retrospective observational study that consisted of 267 patients (group A) who underwent aortic surgery from July 2013 to December 2016 and made a formula for predicting the SFL at the termination of CPB in group A by a multiple linear regression analysis. The validity of this formula was then examined in another 60 patients (group B) who underwent aortic surgery from January 2017 to December 2017. RESULTS: We developed the following predictive formula: SFL at the termination of CPB (mg/dL) = 14.7 + 0.44 × preoperative SFL (mg/dL) + (- 0.14) × CPB time (min) + 0.64 × preoperative body weight (kg) + (- 17.3) × lateral thoracotomy (Yes/No, Yes: 1, No: 0). In group B, the predictive formula proved to be statistically valid in group B (R2 = 0.531, p < 0.001). CONCLUSION: The SFL at the termination of CPB in aortic surgery can be predicted by the preoperative SFL, body weight, CPB time and surgical approach. The predictive formula is useful for developing a hemostasis strategy, including preparing for blood transfusion.

Cardiac fiber tracking on super high-resolution CT images: a comparative study.

Purpose: High-resolution cardiac imaging and fiber analysis methods are required to understand cardiac anatomy. Although refraction-contrast x-ray CT (RCT) has high soft tissue contrast, it cannot be commonly used because it requires a synchrotron system. Microfocus x-ray CT ( µ CT ) is another commercially available imaging modality. Approach: We evaluate the usefulness of µ CT for analyzing fibers by quantitatively and objectively comparing the results with RCT. To do so, we scanned a rabbit heart by both modalities with our original protocol of prepared materials and compared their image-based analysis results, including fiber orientation estimation and fiber tracking. Results: Fiber orientations estimated by two modalities were closely resembled under the correlation coefficient of 0.63. Tracked fibers from both modalities matched well the anatomical knowledge that fiber orientations are different inside and outside of the left ventricle. However, the µ CT volume caused incorrect tracking around the boundaries caused by stitching scanning. Conclusions: Our experimental results demonstrated that µ CT scanning can be used for cardiac fiber analysis, although further investigation is required in the differences of fiber analysis results on RCT and µ CT .

The incidence and risk factors of hypofibrinogenemia in cardiovascular surgery.

OBJECTIVE: Cardiovascular surgery often causes massive bleeding due to coagulopathy, with hypofibrinogenemia being a major causative factor. We assessed the intraoperative incidence of hypofibrinogenemia and explored predictors of hypofibrinogenemia. METHODS: The intraoperative serum fibrinogen level (SFL) was routinely measured in 872 consecutive patients [mean age: 66.9 ± 13.3 years; 598 men (68.6%)] undergoing cardiovascular surgery from July 2013 to November 2016 at Nagoya University Hospital. There were 275 aortic surgeries, 200 cases of coronary artery bypass grafting (CABG), 334 valvular surgeries and 63 other surgeries. We estimated hypofibrinogenemia incidence (intraoperative lowest SFL ≤ 150 mg/dL) and identified its predictors by a logistic regression analysis. RESULTS: The average intraoperative lowest SFL of all cases, aortic surgery, CABG and valvular surgery was 185 ± 71, 156 ± 65, 198 ± 69 and 198 ± 68 mg/dL, respectively. Aortic surgery had a significantly lower intraoperative lowest SFL than CABG (p < 0.001) and valvular surgery (p < 0.001). The incidence of hypofibrinogenemia was 32.8%, 50.2%, 26.5% and 22.8% in all cases, aortic surgery, CABG and valvular surgery, respectively. The predictors of hypofibrinogenemia were the preoperative SFL, re-do surgery and perfusion time. A receiver operating characteristics curve analysis showed that the best preoperative SFL cutoff value for predicting hypofibrinogenemia was 308.5 mg/dL. Assuming preoperative SFL 300 mg/dL as the cutoff, the odds ratio for hypofibrinogenemia was 7.22 (95% confidence interval 5.26-9.92, p < 0.001). CONCLUSIONS: The incidence of hypofibrinogenemia in aortic surgery was high. The preoperative SFL, re-do surgery and perfusion time were identified as predictors for hypofibrinogenemia. Intraoperative measurement of SFL is important for detecting hypofibrinogenemia and applying appropriate and prompt transfusion treatment.

Spinal cord injury following aortic arch replacement.

PURPOSE: Postoperative spinal cord injury is a devastating complication after aortic arch replacement. The purpose of this study was to determine the predictors of this complication. METHODS: A group of 254 consecutive patients undergoing aortic arch replacement via median sternotomy, with (n = 78) or without (n = 176) extended replacement of the upper descending aorta, were included in a risk analysis. The frozen elephant trunk technique was used in 46 patients. The patients' atherothrombotic lesions (extensive intimal thickening of > 4 mm) were identified from computed tomography images. RESULTS: Complete paraplegia (n = 7) and incomplete paraparesis (n = 4) occurred immediately after the operation (permanent spinal cord injury rate, 1.97%; transient spinal cord injury rate, 2.36%). A multivariable logistic regression analysis identified the use of the frozen elephant trunk technique (odds ratio 36.3), previous repair of thoracoabdominal aorta or descending aorta (odds ratio 29.4), proximal atherothrombotic aorta (odds ratio 9.6), chronic obstructive lung disease (odds ratio 7.1) and old age (odds ratio 1.1) as predictors of spinal cord injury (p < 0.0001, area under curve 0.93). CONCLUSIONS: Spinal cord injury occurs with a non-negligible incidence following aortic arch replacement. The full objective assessment of the morphology of the whole aorta and the recognition of the risk factors are mandatory.

Biodegradable vs Nonbiodegradable Cardiac Support Device for Treating Ischemic Cardiomyopathy in a Canine Heart.

Clinical studies of the efficacy of the nonbiodegradable CorCap device have shown inconsistent findings, at least in part, because of device-related impairment of diastolic cardiac function. We hypothesized that use of biodegradable material for the cardiac support device could contribute to an improvement in the diastolic function of the failing heart. Polyglycolic acid and polyethylene terephthalate were used to prepare biodegradable and nonbiodegradable cardiac support devices, respectively. Twelve-month-old beagles underwent anterior coronary artery ligation. One week after, the beagles were randomly assigned for implantation of a biodegradable cardiac support device (n = 7), nonbiodegradable cardiac support device (n = 8), or sham operation (n = 8). Twelve weeks after coronary artery ligation, the biodegradable group showed a significantly greater recovery of echocardiographical ejection fraction than the nonbiodegradable and the sham groups (40% ± 3.3%, 32% ± 2.5%, and 29 ± 2.6%, respectively). Of note, diastolic function, as assessed by Tau, -dp/dt min, and end-diastolic pressure-volume relationship in the cardiac catheter, was significantly better in both left and right ventricles in the biodegradable group than in the nonbiodegradable group. Moreover, global end-systolic wall stress was significantly lower in the 2 device groups than in the sham group (P < 0.03). Furthermore, global end-diastolic wall stress was significantly less in the biodegradable device group than in the nonbiodegradable group (P < 0.02). The cardiac support devices made of biodegradable material were more effective in improving systolic function, with preservation of diastolic function in the canine infarct heart, than devices made of nonbiodegradable material.

Beneficial effects of a cardiac support device on left ventricular remodeling after posterior myocardial infarction: an evaluation by echocardiography, pressure-volume curves and ventricular histology.

PURPOSE: Posterior myocardial infarction (MI) can induce LV remodeling and ischemic mitral regurgitation (IMR). The protective effects of a cardiac support device (CSD) against LV remodeling and IMR after posterior MI have been poorly documented. METHODS: Posterior MI was induced by ligation of the left circumflex coronary artery in beagle dogs. After 7 days, the dogs were randomized to a CSD placement (CSD group, n = 8) or no treatment (CTL group, n = 8). RESULTS: At 3 months after MI, the LV remodeling was less marked and the LV and RV systolic functions were better in the CSD group than in the CTL group. Neither the RV nor LV diastolic function (min dP/dt, Tau and EDPVR) was disturbed by the CSD. IMR was consistently prevented in our canine model. CONCLUSION: Early application of a CSD after posterior MI can attenuate LV remodeling without causing any deterioration of the biventricular diastolic function.

Impact of cardiac support device combined with slow-release prostacyclin agonist in a canine ischemic cardiomyopathy model.

BACKGROUND: The cardiac support device supports the heart and mechanically reduces left ventricular (LV) diastolic wall stress. Although it has been shown to halt LV remodeling in dilated cardiomyopathy, its therapeutic efficacy is limited by its lack of biological effects. In contrast, the slow-release synthetic prostacyclin agonist ONO-1301 enhances reversal of LV remodeling through biological mechanisms such as angiogenesis and attenuation of fibrosis. We therefore hypothesized that ONO-1301 plus a cardiac support device might be beneficial for the treatment of ischemic cardiomyopathy. METHODS: Twenty-four dogs with induced anterior wall infarction were assigned randomly to 1 of 4 groups at 1 week postinfarction as follows: cardiac support device alone, cardiac support device plus ONO-1301 (hybrid therapy), ONO-1301 alone, or sham control. RESULTS: At 8 weeks post-infarction, LV wall stress was reduced significantly in the hybrid therapy group compared with the other groups. Myocardial blood flow, measured by positron emission tomography, and vascular density were significantly higher in the hybrid therapy group compared with the cardiac support device alone and sham groups. The hybrid therapy group also showed the least interstitial fibrosis, the greatest recovery of LV systolic and diastolic functions, assessed by multidetector computed tomography and cardiac catheterization, and the lowest plasma N-terminal pro-B-type natriuretic peptide levels (P < .05). CONCLUSIONS: The combination of a cardiac support device and the prostacyclin agonist ONO-1301 elicited a greater reversal of LV remodeling than either treatment alone, suggesting the potential of this hybrid therapy for the clinical treatment of ischemia-induced heart failure.

[An approach to vacuum-assisted closure therapy using the S-B Vac].

Vacuum-assisted closure (VAC) therapy is increasingly applied for patients with wound dehiscence or mediastinitis caused by surgical site infection (SSI) after open-heart surgery. We have used wall suction for such cases in the past. But this method was an obstacle for improvement of the quality of life (QOL) of the patient. Since the S-B Vac is portable, this equipment may allow wound healing without decreasing QOL. Here, we report a case in which VAC therapy was performed using the S-B Vac.

Reoperation of the proximal aorta: impact of presternotomy extracorporeal circulation on clinical outcomes.

PURPOSE: Adverse events can occur during a sternotomy for reoperation of the proximal aorta. Presternotomy extracorporeal circulation is often employed to avoid catastrophic events. The purpose of this study was to investigate the impact of presternotomy extracorporeal circulation on clinical outcomes of redo proximal aortic surgery. METHODS: Between January 1990 and December 2005 a total of 21 aneurysms or dissections of the proximal aorta were repaired via a repeat sternotomy. Extracorporeal circulation was established before the sternotomy in 9 (49%) patients and after the sternotomy in 12 (51%) patients. RESULTS: There were no statistically significant differences in the age, sex, emergency surgery, chronic obstructive pulmonary disease, and renal function between the groups. Femoral cannulation was used more often in the presternotomy extracorporeal circulation group (8/9, 89% vs. 1/12, 8.3%; P = 0.000). The difference in the pump time did not reach a statistically significant level. The 30-day and in-hospital mortality rates were 11% (1/9) and 11% (1/9) in the presternotomy extracorporeal circulation group and 0% (0/12) and 17% (2/12) in the poststernotomy extracorporeal circulation group. There were no statistically significant differences in stroke, respiratory failure, myocardial infarction, or renal failure. There was a trend toward a longer hospital stay in the presternotomy extracorporeal circulation group (85.8 vs. 48.1 days; P = 0.06). CONCLUSION: Presternotomy extracorporeal circulation was not associated with any major adverse outcomes such as death, stroke, or renal failure.

A pilot randomized study of the neutrophil elastase inhibitor, Sivelestat, in patients undergoing cardiac surgery.

The primary objective of this study was to determine the feasibility and safety of treatment with Sivelestat in humans to attenuate post-cardiopulmonary bypass lung injury. Twenty patients scheduled to undergo on-pump coronary artery bypass surgery were randomized to receive either 0.3 mg/kg/h intravenous Sivelestat sodium (Sivelestat group; n=10) or isotonic sodium chloride solution (placebo group, n=10), peri-operatively. Postoperative adverse events were recorded until hospital discharge. The alveolar-arterial oxygen gradient (A-aDO(2)), intrapulmonary shunt (Qs/Qt) and dynamic lung compliance were determined four times peri-operatively as secondary exploratory outcomes. All patients completed study protocol without discontinuation of intervention. The number of total adverse clinical outcomes, including atrial fibrillation and superficial wound infection, was nine in seven patients in the placebo group and four in four patients in the Sivelestat group (P=0.37). The mean duration of the postoperative hospital stay was shorter in the Sivelestat group (19.0+/-3.4 vs. 25.6+/-9.1, P=0.04). The exploratory analysis of relative changes in lung functions showed trends toward attenuation of lung injury in the Sivelestat group in all three pulmonary parameters, though the inter-group difference could be due to chance (P>0.05). It is feasible to administer Sivelestat as a preventive measure against lung dysfunction after cardiopulmonary bypass.

Midkine prevents ventricular remodeling and improves long-term survival after myocardial infarction.

Cardiac remodeling is thought to be the major cause of chronic heart dysfunction after myocardial infarction (MI). However, molecules involved in this process have not been thoroughly elucidated. In this study we investigated the long-term effects of the growth factor midkine (MK) in cardiac remodeling after MI. MI was produced by ligation of the left coronary artery. MK expression was progressively increased after MI in wild-type mice, and MK-deficient mice showed a higher mortality. Exogenous MK improved survival and ameliorated left ventricular dysfunction and fibrosis not only of MK-deficient mice but also of wild-type mice. Angiogenesis in the peri-infarct zone was also enhanced. These in vivo changes induced by exogenous MK were associated with the activation of phosphatidylinositol 3-kinase (PI3K)/Akt and MAPKs (ERK, p38) and the expression of syndecans in the left ventricular tissue. In vitro experiments using human umbilical vein endothelial cells confirmed the potent angiogenic action of MK via the PI3K/Akt pathway. These results suggest that MK prevents the cardiac remodeling after MI and improves the survival most likely through an enhancement of angiogenesis. MK application could be a new therapeutic strategy for the treatment of ischemic heart failure.

Entry closure and aortic tailoring for chronic type B aortic dissection.

Although graft replacement for chronic type B dissection is the standard operation, this operation is invasive to some extent, and the mortality and morbidity remain high. We describe a simple and less invasive technique using initial entry closure and aortic tailoring of the dissected lumen.

Three-dimensional numerical simulation of blood flow in the aortic arch during cardiopulmonary bypass.

OBJECTIVE: To better understand the mechanism of stroke during cardiopulmonary bypass, it is necessary to obtain information on the location of turbulence, wall pressure, and flow distribution within the aortic arch. METHODS: Blood flow was numerically simulated using the finite element method in the following representative case: a curved arterial cannula was inserted into the anterior wall of the distal ascending aorta 2 cm below the orifice of brachiocephalic artery. Perfusion was performed, with a bypass flow index of 2.5l min(-1) m(-2). Computational grids, consisting of 1,493,297 tetrahedral elements, were generated. RESULTS: The highest wall pressure (3104.8 Pa) was observed at the superior-posterior wall of the aorta below the orifice of the brachiocephalic artery where jet flow impingement occurred. The maximum wall shear stress was 25.1 Pa. High velocity vortex started below the orifice of the brachiocephalic artery. The turbulent flows continued along the posterior wall and then mainly flowed off into the left subclavian artery. Therefore, in the present case, an embolic event in the territory of the left subclavian artery could occur if a plaque was present at the superior-posterior wall of the aorta below the orifice of the brachiocephalic artery. The flow rates in each of the branches were 132, 613, 175, and 821 ml/min for the right subclavian, right common carotid, left common carotid, and left subclavian artery, respectively. CONCLUSION: This study confirmed that blood flow during cardiopulmonary bypass can be simulated and visualized. Computational fluid dynamics could be applied in the future to assess an individual's risk of stroke. Further multiple representative cases need to be simulated.

Predicting early coronary artery bypass graft failure by intraoperative transit time flow measurement.

BACKGROUND: A primary limitation of using transit time flow measurement to predict early graft failure in coronary artery bypass grafting has been the lack of cutoff values for objective criteria. METHODS: We analyzed a total of 261 grafts that were evaluated by intraoperative transit time flow measurement and underwent early postoperative coronary angiography within 3 months of surgery. Based on the control angiography, failing grafts were defined as occluded or patent grafts with greater than 50% stenosis or poor flow characteristics. Normal and failing graft indicators were compared according to the graft territories. RESULTS: According to the receiver operating characteristic curve analysis for the grafts to left coronary arteries, a mean flow of 15 mL/min or less, a pulsatility index of 5.1 or higher, and a backward flow of 4.1% or higher were found to be the optimal cutoff criteria to predict early graft failure. Similarly, for the grafts to right coronary arteries, the cutoff values were 20 mL/min, 4.7, and 4.6%, respectively. A systolic dominant flow curve pattern was a risk factor only in grafts to the left coronary arteries. Negative predictive values of these cutoff criteria ranged from 0.91 to 0.96, whereas positive predictive values ranged from 0.31 to 0.80. CONCLUSIONS: Using these criteria, transit time flow measurement may be a useful method to predict early graft failure. However, surgeons should be aware of the low positive predictive values to avoid unnecessary graft revision.

Type B aortic dissection associated with coarctation of the aorta.

We describe a case of acute type B dissection associated with coarctation of the aorta, a rare pathological combination. An intimal tear was located just distal to the coarctation. Aortic dilatation started below the coarctation and extended to the level of the diaphragm. We performed descending aorta replacement from the distal aortic arch to the level of the 9th intercostal arteries through a left posterolateral thoracotomy in the fifth intercostal space. Arterial cannulations were placed on the right femoral artery and just proximal to the coarctation site in the descending aorta. To preserve the patent 10th and lower intercostal arteries, longitudinal plication of dilated pseudo-lumen was applied from the distal cut end to the level of the diaphragm. The postoperative course was uneventful.

Aortic arch aneurysm of Takayasu arteritis associated with entero-Behçet disease.

We report a case of a ruptured aortic arch aneurysm due to Takayasu arteritis concomitant with entero-Behçet disease. A 53-year-old woman with total left lung atelectasis underwent emergency total aortic arch replacement with a modified Bentall operation and elephant trunk procedure. The postoperative course was highly eventful. A pseudoaneurysm of the left coronary button occurred with mediastinitis due to fistula of the left bronchus into the remnant of the aneurysmal wall. The left main trunk was reconstructed with a saphenous vein graft. The left bronchial fistula into the esophagus was exposed and an esophageal stent was placed. Finally, the saphenous vein graft ruptured and the patient expired. The autopsy diagnosis was Takayasu arteritis. This is the first reported case of concomitant Takayasu arteritis and entero-Behçet disease.