Efficacy of intentional undersized thoracic endovascular repair for Stanford type B aortic dissection.

OBJECTIVE: Thoracic endovascular aneurysm repair (TEVAR) is widely used for the treatment of aortic dissection. Endograft oversizing is a risk factor for stent graft-induced new entry tears and retrograde type A aortic dissection. However, there is no clear consensus on the optimal graft size selection for Stanford type B acute or subacute aortic dissection (TBAD). Herein, we examined the safety and efficacy of TEVAR using an intentionally undersized endograft to treat TBAD. METHODS: This retrospective chart review study included 82 patients who underwent TEVAR for acute or subacute Stanford TBAD between 2015 and 2022. We measured the true lumen diameter just distal to the subclavian artery and opted for a stent graft of the same diameter. In instances where deformation resulting from false lumen pressure displacement was pronounced, we measured the diameter at the site just proximal to the subclavian artery. Patients' characteristics, procedural, in-hospital, and follow-up data, and aortic remodeling were analyzed. The aortic diameter was analyzed using one-way analysis of variance followed by Dunnett's test. Survival and freedom from reintervention were estimated using Kaplan-Meier curves. RESULTS: The follow-up rate was 98.4%. The mean age was 58.3 ± 12.3 years, and 76 were men (92.7%). The mean diameters of the stent graft and native proximal landing zone were 30.9 ± 3.2 mm and 30.8 ± 3.0 mm, respectively. The oversize rate of the stent graft in relation to the native proximal aortic diameter was 0.3% ± 4.7%. In-hospital mortality was observed in one patient, retrograde type A aortic dissection in one patient, distal stent graft-induced new entry tear in zero patients, and type 1a endoleak in 22 patients (26.8%). Type 1a endoleaks, characterized by antegrade false lumen blood flow originating from the primary entry, in 12 patients spontaneously disappeared within 1 year of follow-up. According to aortic remodeling, 59 patients (86.8%) achieved complete aortic remodeling at the aortic arch level and 51 (75.0%) at the eighth thoracic vertebral level. The diameters of the aortic arch and descending aorta were significantly reduced compared with the postoperative measurements (P <.001). Survival rates were 97.5% and 93.6% at 1 and 3 years, respectively. Freedom from reintervention was 84.7% and 84.7% at 1 and 3 years, respectively. CONCLUSIONS: Intentionally undersized TEVAR was safe and achieved acceptable aortic remodeling despite a high rate of type 1a endoleaks. A type 1a endoleak was acceptable as it primarily diminished during the mid-term follow-up.

Single Versus Multiple Arterial Revascularization in Patients With Reduced Renal Function: Long-term Outcome Comparisons in 23,406 CABG Patients From Ontario, Canada.

OBJECTIVE: To compare the long-term outcomes of MAR versus SAR in patients with renal insufficiency. SUMMARY OF BACKGROUND DATA: Previous studies have been insufficiently powered to address whether MAR confers long-term benefit over SAR in patients with renal dysfunction who require CABG. METHODS: We conducted retrospective cohort study in Ontario, Canada of patients who underwent isolated CABG (n = 23,406). The primary outcome was MACE, defined as the composite of stroke, myocardial infarction, and repeat revascularization. We compared patients by matching them on the propensity to have received SAR versus MAR, within groups with preoperative glomerular filtration rate (GFR) ≥60 mL/min/1.73 m2; GFR between 30 and 60; and GFR <30. RESULTS: In patients with GFR ≥60, the use of MAR versus SAR was associated with a lower rate of MACE [hazard ratio (HR) 0.87 (0.80-0.94)], and a lower rate of long-term mortality [HR 0.87 (0.79-0.97)]. In those with GFR between 30 and 60, MAR was not associated with a difference in MACE [HR 1.04 (0.87-1.26)], and a lower rate of long-term mortality [HR 0.75 (0.65-0.87)] was observed. In those with GFR <30, MAR was not associated with a difference in outcomes. CONCLUSIONS: MAR versus SAR does not correlate with a difference in MACE amongst patients with GFR between 30 and 60 and better survival raises the possibility of indication bias. Furthermore, MAR did not confer a benefit in those with severely reduced renal function. These data suggest that the potential long-term benefits of using MAR in CABG patients with renal insufficiency may be offset by competing health risks.

[Transient Left Ventricular Dysfunction after Giant Coronary Aneurysm Resection and Repair of Coronary Arteriovenous Fistula with Coronary Artery Bypass Grafting:Report of a Case].

Coronary artery aneurysm with coronary arteriovenous fistula is a relatively rare clinical setting. We report a surgical case of a 69-year-old male with a giant coronary artery aneurysm, finding coronary arteriovenous fistula on computed tomography (CT). We performed complete aneurysm excision and coronary artery bypass grafting with the left internal thoracic artery to the posterolateral branch. The fistula was located between the giant aneurysm on the circumflex artery and the coronary vein close to the coronary sinus, closed with aneurysm sac. The postoperative CT found no residual aneurysm and fistula. However, the great cardiac vein was thrombosed, and the impeded venous flow by the thrombus seemed to reduce the left ventricular ejection fraction (LVEF). Four months after the operation, the LVEF improved to the preoperative level.

Renal insufficiency and severe coronary artery disease: should coronary artery bypass grafting, off-pump coronary artery bypass grafting or percutaneous coronary intervention be performed?

PURPOSE OF REVIEW: Chronic kidney disease (CKD) is an important determinant of long-term survival. However, the optimal revascularization strategy for patients with CKD is still controversial. Herein we review the impact of different treatment modalities on the outcomes of patients with CKD. RECENT FINDINGS: CABG could confer better long-term outcomes than PCI in patients with CKD, irrespective of CKD severity. CABG as compared with PCI may be associated with improved long-term survival albeit higher short-term risk. Off-pump as compared with on-pump CABG may be associated with better short-term outcomes but no demonstrable long-term benefit. In CKD patients who are treated with PCI, the use of drug-eluting stents may be associated with better intermediate-term outcomes than bare metal stents. SUMMARY: There is insufficient evidence to inform the optimal revascularization strategy for patients with CKD and severe coronary artery disease. CABG as compared with PCI confers greater long-term benefit but higher upfront risk. A multidisciplinary, team-based evaluation based on individual patient comorbidity, frailty and anatomical disease burden, is recommended when making treatment decisions.

Predictors of the need for pacemaker implantation after the Cox maze IV procedure for atrial fibrillation.

PURPOSE: The Cox maze IV (CMIV) procedure is being used increasingly frequently for surgical ablation of atrial fibrillation (AF). This study aimed to identify the risk factors of the need for postoperative pacemaker implantation (PMI) after CMIV. METHODS: Preoperative, intraoperative, and postoperative data were retrospectively collected from 67 consecutive patients who underwent CMIV at our institution; 7 (10.4%) required PMI (as a treatment of brady AF or sick sinus syndrome). RESULTS: Patients who needed PMI tended to have lower preoperative heart rates than those who did not on a 12-lead electrocardiogram (ECG; 68.7 ± 11.6 vs. 79.1 ± 18.5 bpm, p = 0.07) and a 24-h ECG (94,772 ± 9800 vs. 109,854 ± 19,078 beats/day, p = 0.03). A multivariate analysis identified a low amplitude of the fibrillatory wave on preoperative ECG as a risk factor of PMI necessity after CMIV [odds ratio = 14.7; 95% confidence interval (CI) 1.9-324.7; p = 0.007] and internal use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (ACEIs/ARBs) as a negative risk factor (odds ratio = 0.16; 95% CI 0.02-0.99; p = 0.049). CONCLUSIONS: A low amplitude of the fibrillatory wave was identified as a risk factor of PMI necessity, whereas the internal use of ACEIs/ARBs diminished the need for PMI. These factors should be considered before CMIV is performed.

[Surgical Embolectomy for Acute Massive Pulmonary Thromboembolism Requiring Percutaneous Cardiopulmonary Support after Thoracoabdominal Aorta Replacement].

A 48-year-old man was admitted to our hospital and underwent thoracoabdominal aorta replacement. Eight days postoperatively, he developed severe dyspnea and transient drop in blood pressure suddenly following walk rehabilitation. Contrast-enhanced computed tomography showed thrombi in the bilateral main pulmonary artery. Respiratory failure and unstable hemodynamics developed, which required percutaneous cardiopulmonary support (PCPS). Because catheter embolectomy and thrombolytic therapy via pulmonary artery catheter were not effective, surgical thrombectomy was performed. PCPS was successfully removed on the following day. The patient was extubated on postoperative day 10 and discharged without complications on day 46 following rehabilitation. It is important to save a critically ill patient with acute pulmonary embolism requiring PCPS, and surgical treatment should be performed without delay in such patients.

Graft placement with an omental flap for ruptured infective common iliac aneurysm in a patient with a continuous flow left ventricular assist device: alternative surgical approach avoiding driveline injury and pathogen identification by 16S ribosomal DNA gene analysis.

Patients supported by mechanical circulatory support have to wait for longer periods for heart transplantation in Japan. Infective events are a major complication and influence survival. Here, we present the case of a patient with an implantable left ventricular assist device for 6 months who had the complication of ruptured infective common iliac aneurysm. Graft placement with an omental flap was successfully performed via the alternative surgical approach to avoid percutaneous driveline injury. In samples of aortic specimens, 16S ribosomal DNA gene analysis identified Helicobacter cinaedi. Complete removal of the infected tissue and correct pathogen identification may have been relevant to the good clinical course.

[Fundamental features on percutaneous cardiopulmonary support].

The fundamental features on percutaneous cardiopulmonary support (PCPS) were reviewed. The number of PCPS installation in Japan has been increasing especially in the area of emergency medicine and cardiology. All-in-one package for PCPS system is becoming a mainstream in clinical practice. It is considered to be crucial to understand the details in characteristics and pitfalls on respective products. The results of nation-wide questionnaire indicate that the detailed criteria for PCPS usage in clinical practice appear to be variable among facilities in Japan;therefore, the formulation of guideline and educational system for PCPS installation is required.

Utilizing a sutureless valve for prosthetic valve endocarditis after aortic root replacement.

BACKGROUND: Reoperation following aortic root replacement is associated with significantly high operative mortality. Etiologies related to infection are known to increase the operative mortality rate more than other etiologies. In such a clinical setting, a sutureless valve could lower the operative mortality by shortening the cardiac arrest and the operative time. CASE PRESENTATION: A 61-year-old male underwent emergent aortic root and total arch replacement with an open stent graft for acute type-A aortic dissection. A bioprosthetic valve was employed for aortic root replacement using the double-sewing ring technique. A fungal infection by Candida parapsilosis was postoperatively detected and improved with intravenous antifungal drug administration. However, he developed congestive heart failure one year later, and the blood cultures turned positive repeatedly for Candida parapsilosis. The prosthetic valve infection was suspected upon identifying vegetation on the bioprosthetic valve through transthoracic echocardiography. The computed tomography scan and operative findings confirmed that the infection was localized on the prosthetic valve. Consequently, the infected valve was removed without a vascular conduit, and a sutureless valve was implanted. The postoperative course was uneventful, without any evidence of recurrent fungal infection, and the patient was discharged on postoperative day 28. CONCLUSIONS: Deploying a sutureless valve can facilitate a more straightforward and minimally invasive redo procedure. Preoperative computed tomography can predict the valve size, which is the key to implanting a sutureless valve successfully after the modified Bentall procedure.

Transcatheter aortic valve replacement in patients with severe aortic stenosis reduced the frequency of intradialytic hypotension.

Intradialytic hypotension (IDH) is a common complication during hemodialysis that increases cardiovascular morbidity and mortality. Aortic stenosis (AS) is a cause of IDH. Transcatheter aortic valve replacement (TAVR) has become an established treatment for patients with severe AS. However, whether TAVR reduce the frequency of IDH has not been investigated. This study aims to verify the efficacy of TAVR for reduction of the frequency of IDH. Consecutive hemodialysis patients who underwent TAVR at Sendai Kosei Hospital from February 2021 to November 2021 with available records 1 month before and 3 months after TAVR were included in the study. IDH was defined as a decrease in systolic blood pressure by 20 mmHg or a decrease in the mean blood pressure by 10 mmHg associated with hypotensive symptoms or requiring intervention. Patients with ≥ 3 episodes of IDH in ten hemodialysis sessions comprised the IDH group. Overall, 18/41 (43.9%) patients were classified into the IDH group. In ten hemodialysis sessions, IDH events were observed 2.1, 4.3, and 0.4 times in the overall cohort, IDH group, and non-IDH group, respectively. After TAVR, the incidence of IDH decreased from 43.2 to 10.3% (p < 0.0001) and IDH improved significantly in 15 patients in the IDH group. The result suggested that severe AS was the major cause of IDH in this cohort, and TAVR may be an effective treatment option for reduction of the frequency of IDH in patients with severe AS.

Preliminary validation of a new magnetic wireless blood pump.

In general, a blood pump must be small, have a simple configuration, and have sufficient hydrodynamic performance. Herein, we introduce new mechanisms for a wireless blood pump that is small and simple and provides wireless and battery-free operation. To achieve wireless and battery-free operation, we implement magnetic torque and force control methods that use two external drivers: an external coil and a permanent magnet with a DC-motor, respectively. Power harvesting can be used to drive an electronic circuit for wireless monitoring (the observation of the pump conditions and temperature) without the use of an internal battery. The power harvesting will be used as a power source to drive other electronic devices, such as various biosensors with their driving circuits. To have both a compact size and sufficient pumping capability, the fully magnetic impeller has five stages and each stage includes four backward-curved blades. The pump has total and inner volumes of 20 and 9.8 cc, respectively, and weighs 52 g. The pump produces a flow rate of approximately 8 L/min at 80 mm Hg and the power generator produces 0.3 W of electrical power at 120 Ω. The pump also produces a minimum flow rate of 1.5 L/min and a pressure of 30 mm Hg for circulation at a maximum distance of 7.5 cm.

[Successful treatment using recombinant thrombomodulin for disseminated intravascular coagulation associated with recurrent prosthetic valve endocarditis].

Prosthetic valve endocarditis(PVE)occasionally evokes sepsis and disseminated intravascular coagulation(DIC). A 46-year-old man developed relapsing active PVE with an annular abscess and suffered from exacerbating sepsis and DIC. Despite the administration of antibiotics, his DIC score increased. Anti-DIC treatment with recombinant thrombomodulin (rTM) was initiated, and his DIC was remarkably resolved. Accordingly, the abscess cavity was closed by using a homograft anterior mitral leaflet, and the aortic root was replaced with the homograft. He is doing well without an evidence of recurrent endocarditis 18 months after the operation. rTM is a new and promising drug for the treatment of DIC with infective endocarditis.

Direct Implant of a Transcatheter Aortic Valve Prosthesis for Prosthetic Mitral Valve Endocarditis.

We describe the case of a 64-year-old woman presenting with severe prosthetic mitral valve endocarditis 1 year after coronary artery bypass grafting and double valve replacement. Echocardiogram revealed high-pressure gradients through the bioprosthetic MV with a bulky vegetation. As the patient had presented operative difficulties due to severe mitral annular calcification, was in renal failure, and in the absence of any perivalvular involvement, an open-heart surgical catheter-based valve implantation was successfully performed after removal of the infected leaflets, leaving the stent frame and sewing cuff behind. Albeit controversial, this case represents an alternative approach for select high-risk reoperative mitral cases with mitral annular calcification.

Cet article décrit le cas d'une femme de 64 ans qui a présenté une endocardite sur prothèse mitrale sévère 1 an après avoir subi un pontage aortocoronarien et un double remplacement valvulaire. L'échocardiogramme a mis au jour des gradients de pression élevés dans la bioprothèse mitrale et une végétation volumineuse. Comme la patiente avait souffert de complications opératoires en raison d'une importante calcification annulaire mitrale et qu'elle était en insuffisance rénale, mais que la zone périvalvulaire n'était pas atteinte, une valve a été implantée par cathéter pendant une opération à cœur ouvert, une fois les lames valvulaires infectées retirées; l'endoprothèse et le manchon de suture ont été laissés en place. Bien que cette méthode puisse susciter la controverse, elle offre une solution de rechange dans certains cas, lorsqu'un patient présentant une calcification annulaire mitrale nécessite une nouvelle intervention associée à un risque élevé.

Frequency and chaotic analysis of pulsatile motion of blood vessel wall related to aneurysm.

BACKGROUND/OBJECTIVE: In this research, using our proposed method, clinical measurements on the pulsatile velocity of blood vessel wall were conducted for cases with aneurysm. Furthermore, detailed analyses of frequency and attracter of trajectories of velocity of blood vessel wall were conducted. On the basis of these analyses, we tried to conduct unified clarification of the change and disturbance of frequency and wave form of pulsatile velocity of blood vessel wall caused by blood vessel diseases such as aneurysm. RESULTS: In the pulsation motion of blood vessel wall, vasomotion, which is a regular long periodic fluctuation of amplitude of the pulsatile velocity of blood vessel wall, was found to exist. Furthermore, the shift of its frequency into low frequency region was found to correspond well with an increase in I∗, an indicator of progressive degree of visco elasticity of blood vessel wall and it reflects the mechanical deterioration of blood vessel wall. This long periodic fluctuation of amplitude of the pulsatile velocity of blood vessel wall exists in the low frequency region that composes the frequency of the pulsatile velocity of blood vessel wall. On the other hand, wave forms in high frequency region that compose the frequency of pulsatile velocity of blood vessel wall were found to correspond well with each pulsatile velocity wave form of blood vessel wall itself and their disturbances caused by the existence of aneurysm was typically reflected in these wave forms. CONCLUSION: By dividing frequencies that compose the frequency of the pulsatile velocity of blood vessel wall into low and high frequency regions and conducting analyses at each region, the possibility of accurate selective detection of blood vessel diseases such as mechanical deterioration of blood vessel wall (low frequency region) and morphological change of blood vessel wall that is aneurysm (high frequency region) was indicated.

A novel diagnostic system for Doppler ultrasound of the peripheral arteries to detect the presence of thoracic aortic aneurysm.

OBJECTIVE: We aimed to develop a novel ultrasound system and examine its feasibility for noninvasively detecting thoracic aortic aneurysm (TAA) in clinical settings. METHODS: We developed a novel ultrasound system consisting of a modified console and data analysis algorithm. The exploratory study included 100 patients hospitalized for elective cardiovascular surgery. After admission, the arterial pulse waveform at the left carotid artery was acquired using the novel system. Based on these data, we inferred the presence of TAA based on arterial viscoelasticity and instability, which are reflected into the time-averaged trajectory of deformation of the blood vessel wall caused by disturbance of blood flow. Meanwhile, all patients underwent computed tomography as preoperative screening to confirm the presence of TAA. The sensitivity and specificity of TAA detection using the novel ultrasound system were calculated. RESULTS: The datasets from 37 patients were not suitable for analysis and were thus discarded. Based on computed tomography findings, 40 patients were categorized into the aneurysm group while 23 were judged not to have and aortic aneurysm. On the other hand, 44 patients were diagnosed as having TAA based on ultrasound findings obtained using the novel system. The overall sensitivity and specificity of the ultrasound system were 0.83 and 0.52, respectively. CONCLUSION: We successfully developed a novel system for noninvasive, ultrasound-based evaluation of the left carotid artery to detect TAA. Although improvements to the probe and diagnostic algorithm are warranted, this device has potential utility for mass screening to detect asymptomatic TAA as part of community-level healthcare programs.

Differential selective hypothermic intercostal artery perfusion: a new method to probe spinal cord perfusion during thoracoabdominal aortic aneurysm repair.

OBJECTIVE: To prevent paraplegia in patients undergoing thoracoabdominal aortic aneurysm repair, the importance of preoperative identification of the Adamkiewicz artery and reconstruction of critical intercostal artery have been advocated. Conversely, significance of collateral network for spinal cord perfusion has been recognized. We invented a new system consisting of a direct monitoring of cerebrospinal fluid temperature (CSFT) and differential selective hypothermic intercostal artery perfusion (D-HIAP). METHODS: After exposing a critical intercostal artery, a 10-mm prosthetic graft was anastomosed in an end to side fashion. A balloon-tipped catheter was inserted into the graft to perfuse with 15 °C blood. Neighboring intercostal arteries were also perfused in the same fashion. Serial monitoring of CSFT was performed. Between January 2011 and January 2015, D-HIAP was employed in 50 patients with Adamkiewicz artery that located within a reconstructed area. RESULTS: Significant CSFT drop was recorded after initiation of D-HIAP in 42 (84%) patients. Of those, 34 (68%) patients showed significantly lowered CSFT with D-HIAP into a single critical intercostal artery. Perfusion into plural intercostal arteries was necessary for CSFT drop in 2 cases (4%), and plural intercostal artery perfusion further enhanced CSFT drop that had been modestly achieved by single intercostal artery perfusion in 6 cases (12%). Eight (16%) patients did not exhibit a significant drop in CSFT even when D-HIAP was employed for the critical and neighboring intercostal arteries. CONCLUSIONS: The detection of a disparity in temperature between the intrathecal space and blood generated by D-HIAP revealed individual variability in CSFT changes, which may imply a complexity in spinal cord perfusion. Intraoperative D-HIAP may help to identify a major blood supply for spinal cord perfusion and underlying collateral network.

Oesophageal mucosal blood flow changes after thoracic endovascular stent graft implantation using a novel sensor probe.

OBJECTIVES: Secondary aorto-oesophageal fistula is a rare, lethal complication occurring after thoracic endovascular aneurysmal repair. The cause of secondary aorto-oesophageal fistula is unknown, but a reduction in local oesophageal mucosal blood flow (OMBF) may be a basis for such a devastating sequela. Our study aims to develop a novel blood flow sensor probe to detect changes in OMBF after thoracic stent graft implantation in an experimental swine model. METHODS: A novel laser Doppler flowmetry sensor probe incorporating an optical fibre sensor within a nasogastric tube was developed using microelectromechanical system technology. OMBF was measured at various levels using this sensor probe, to test its feasibility before and after thoracic endovascular stent graft implantation covering Th4-Th8 vertebral levels in 6 swine. RESULTS: In the middle oesophagus (Th5-Th7), where the aorta was covered with a stent graft, the measured OMBFs were significantly decreased after thoracic endovascular stent graft implantation than those of baseline (8.6 ± 2.7 vs 18.4 ± 7.9 ml/min/100 g, P < 0.0001), followed by a plateau period for at least 2 h after stent grafting (8.7 ± 3.3 ml/min/100 g, P < 0.0001 vs baseline). OMBFs in the upper (Th1-Th3) and lower (Th9-Th11) oesophagus, where the aorta was not covered with a stent graft, were unaffected by thoracic endovascular stent grafting. CONCLUSIONS: The novel laser Doppler flowmetry sensor probe was useful to monitor precise changes of OMBF in a swine model, demonstrating a significant reduction in OMBF after thoracic endovascular stent graft implantation.

Predictors of Heparin Resistance Before Cardiovascular Operations in Adults.

BACKGROUND: Heparin resistance (HR) is often encountered during cardiovascular operations that require cardiopulmonary bypass. Clinical risk factors and the mechanism underlying heparin resistance are yet to be determined. The aim of this study was to elucidate the clinically valid preoperative predictors related to HR. METHODS: The study evaluated 489 patients undergoing cardiovascular operations. Of these, 25 patients presented with HR and received antithrombin III for the initiation of cardiopulmonary bypass with an effective activated coagulation time. The remaining 464 patients, who did not receive antithrombin III, served as controls (NHR). Preoperative patient demographic and laboratory data were analyzed to identify risk factors for HR. RESULTS: The preoperative laboratory data showed platelet count, fibrinogen, D-dimer, creatinine, and C-reactive protein were significantly higher in the HR group than in the NHR group. As expected, the antithrombin III level was significantly lower overall in the HR group (86.0% vs 95.5%, p = 0.009); however, 80% of the patients in the HR group showed normal antithrombin III levels preoperatively. Multivariable logistic regression analysis identified chronic aortic dissection, chronic obstructive pulmonary disease, smoking, and elevated fibrinogen levels as independent predictors for HR. CONCLUSIONS: HR was shown to be associated with preoperative high fibrinogen levels, a smoking habit, and a preoperative diagnosis of chronic, but not acute, aortic dissection, with chronic obstructive pulmonary disease as comorbidity. Administration of antithrombin III resolved HR in all of the affected patients, even when their preoperative antithrombin III level was within the normal limit.