Percutaneous Cannulation of Femoral Vessels in Minimally Invasive Cardiac Surgery.

OBJECTIVE: Despite the recent trend of access miniaturization in minimally invasive cardiac surgery (MICS) surgical "cut down (CD)" for femoral cannulation remains the standard at many centers. Percutaneous vascular closure (PVC) devices have recently been introduced for minimizing invasiveness during interventional diagnostic and therapy. This report summarizes the initial experience with this new approach in the setting of MICS, with a special focus on safety and advantages. METHODS: Percutaneous cannulation with a standard protocol including preoperative computer tomography imaging and intraoperative point-of-care ultrasound guidance was performed in 93 consecutive patients from September 2018 until February 2020, while conventional "CD" procedure performed in 218 patients in the previous period. We analyzed patients' characteristics and compared access site complications of PVC group versus conventional "CD" group. RESULTS: As far as operative/postoperative outcome, the duration of intensive care unit stay as well as hospital stay was statistically shorter in PVC compared with CD (CD vs. PVC: 2.74 ± 3.83 vs. 2.16 ± 2.01 days, p < 0.01, 16.7 ± 8.75 vs. 13.0 ± 4.96 days, p < 0.001, respectively). Further, we found no femoral infection or lymphocele in the PVC group, whereas 4 cases of wound complications were observed in the CD group. CONCLUSION: According to our results, percutaneous closure system for femoral vessels in MICS seems to be beneficial with the assist of preoperative computed tomography and intraoperative Doppler guidance.

Development of modified laser Doppler flowmetry device for real-time monitoring of esophageal mucosal blood flow: a preclinical assessment with an animal model.

This study aimed to modify a laser Doppler flowmeter designed and assembled at our institute. After measuring sensitivity evaluation in ex vivo experiments, we confirmed the efficacy of this new device for monitoring real-time esophageal mucosal blood flow changes after thoracic stent graft implantation by simulating various clinical situations in an animal model. Thoracic stent graft implantation was performed in a swine model (n = 8). Esophageal mucosal blood flow decreased significantly from baseline (34.1 ± 18.8 ml/min/100 g vs. 16.7 ± 6.6 ml/min/100 g, P < 0.05) in the lower esophagus (Th6-Th8) where the stent graft covered the aorta. In the hemorrhagic shock model (shock index ≥ 1.0), esophageal mucosal blood flow showed a remarkable change from baseline in the upper esophagus (Th1-Th3), where the stent graft did not cover the aorta (20.8 ± 9.8 ml/min/100 g vs. 12.9 ± 8.6 ml/min/100 g, P < 0.01); however, it returned to the baseline value within a 30-min period. Mucosal blood flow remained stable in the esophagus, where the stent graft did not cover the aorta. After elevating the mean blood pressure to > 70 mmHg with continuous intravenous noradrenaline infusion, esophageal mucosal blood flow increased significantly in both regions; however, the reaction was different between the two regions. Our newly developed laser Doppler flowmeter could measure real-time esophageal mucosal blood flow changes in various clinical situations during thoracic stent graft implantation in a swine model. Hence, this device can be applied in many medical fields by downsizing it.

Coronary artery bypass grafting under sole Impella 5.0 support for patients with severely depressed left ventricular function.

Selection of the ideal surgical procedure for coronary revascularization in patients with severe cardiac dysfunction at times may represent a challenge. In recent years, with the advent of surgical large microaxial pumps, e.g., Impella 5.0 (Abiomed Inc., Boston, USA), specific support and effective unloading of the left ventricle has become available. In the interventional field, good results have been achieved with smaller microaxial pumps in the setting of so-called protected percutaneous coronary intervention. In this study, we would like to share our early experience with surgical coronary revascularization under the sole support of Impella 5.0, omitting the use of heart-lung machine in three cases of severe cardiac dysfunction due to complex ischemic heart disease. Effective circulatory support intraoperatively and postoperatively speaks in favor of this technique in selected patients.

New hemostatic technique with combined use of Hydrofit® and Surgicel®: an in vitro and in vivo study.

We developed an effective hemostatic technique using Hydrofit® and Surgicel® simultaneously. The aim of this study was to demonstrate the hemostatic efficacy of the Hydrofit® and Surgicel® combination technique through an in vitro experiment and to elucidate mid-term consequences of the combined components through an in vivo experiment. For the in vitro experiment, a closed circuit using a heparin-coated cardiopulmonary bypass circuit and a prosthetic graft was created. The amount of bleeding from the prosthetic graft was measured, and the following three hemostatic methods were applied: only gauze compression in control group, Hydrofit® application in Hydrofit group, Surgicel® spread Hydrofit® application in Hydrofit and Surgicel (HS) group, respectively. In the in vivo experiment, Hydrofit® and/or Surgicel® were implanted under skin on the back of rats (n = 10) at 4 points. In the control group, only an incision was made; in the Hydrofit, Surgicel, and HS groups, Hydrofit® and/or Surgicel® was implanted. One and three months later, each of the five rats were killed and in each section histopathologic examination was carried out. In the in vitro experiment, the amount of bleeding was 7.84 ± 1.08, 2.26 ± 1.02, and 0.87 ± 0.38 ml in the control, Hydrofit, and HS groups, respectively. The amount of bleeding in the HS group was more suppressed than in the Hydrofit group (p = 0.012). In the in vivo experiment, the maximal depth diameter of each remaining hemostatic sealant was measured. After 3 months, the diameter was 0, 2289.0 ± 768.2, 3850.3 ± 935.8 µm in Surgicel, Hydrofit and HS groups, respectively. The diameter was significantly increased in the HS group compared with the Surgicel and Hydrofit groups (p < 0.001, respectively,). In conclusion, the combination of Hydrofit® and Surgicel® was effective in achieving hemostasis. The remnants of Hydrofit® and Surgicel® were present for a long time in the tissues which could compress the surrounding tissue.

Aortic Insufficiency Causes Symptomatic Heart Failure during Left Ventricular Assist Device Support.

De novo aortic insufficiency is often documented during long-term left ventricular assist device (LVAD) support, despite the absence of aortic insufficiency at the time of LVAD implantation. However, whether aortic insufficiency affects long-term mortality and symptomatic heart failure in LVAD-supported patients remains controversial. We aimed to examine whether aortic insufficiency development influenced mortality and symptomatic heart failure following LVAD implantation. Fifty-three patients who underwent durable LVAD implantation between January 1, 2008 and April 31, 2017 were retrospectively examined in a single center institute. After discharge, we performed the echocardiographic examination in accordance with the Japanese registry for the mechanically assisted circulatory support protocol. Aortic insufficiency was graded on an interval scale (severe = 4, moderate = 3, mild = 2, trivial or none = 1). Kaplan-Meier estimates for long-term mortality at the follow-up were generated. We used a logistic regression model to identify risk factors for symptomatic heart failure. The overall median duration of LVAD support was 856.3 ± 430.8 days (range, 12-1,744 days). We did not observe a significant difference in long-term mortality in patients with aortic insufficiency ≥ 3 grade compared with patients with aortic insufficiency < 3 grade (P = 0.767; log-rank). Aortic insufficiency was associated with an increased risk for heart failure event after discharge (odds ratio, 4.12; confidence interval, 1.48-16.93; P = 0.005). Aortic insufficiency was an independent risk factor for symptomatic heart failure and was not associated with long-term mortality. Aortic insufficiency progression was associated with symptomatic heart failure.

The analysis of left ventricular ejection fraction after minimally invasive surgery for primary mitral valve regurgitation.

BACKGROUND: Although minimally invasive mitral valve surgery (MIMVS) has become the first choice for primary mitral regurgitation (MR) in recent years, clinical evidence in this field is yet limited. The main focus of this study was the analysis of preoperative (Pre), postoperative (Post), and 1-year follow-up (Fu) data in our series of MIMVS to identify factors that have an impact on the left ventricular ejection fraction (LVEF) evolution after MIMVS. METHODS: We reviewed the perioperative and 1-year follow-up data from 436 patients with primary MR (338 isolated MIMVS und 98 MIMVS combined with tricuspid valve repair) to analyze patients' baseline characteristics, the change of LV size, the postoperative evolution of LVEF and its factors, and the clinical outcomes. RESULTS: The overall mean value of ejection fraction (EF) slightly decreased at 1-year follow-up (mean change of LVEF: -2.63 ± 9.00%). A significant correlation was observed for preoperative EF (PreEF) und EF evolution, the higher PreEF the more pronounced decreased EF evolution (in all 436 patients; r = -.54, p < .001, in isolated MIMVS; r = -.54, p < .001, in combined MIMVS; r = -.53, p < .001). Statistically significant differences for negative EF evolution were evident in patients with mild or greater tricuspid valve regurgitation (TR) (in all patients; p < .05, odds ratio [OR] = 1.64, in isolated MIMVS; p < .01, OR = 1.93, respectively). Overall clinical outcome in New York Heart Association classification at 1 year was remarkably improved. CONCLUSIONS: Our results suggest an excellent clinical outcome at 1 year, although mean LVEF slightly declined over time. TR could be a predictor of worsened follow-up LVEF in patients undergoing MIMVS.

PPAR-Gamma Activation May Inhibit the In Vivo Degeneration of Bioprosthetic Aortic and Aortic Valve Grafts under Diabetic Conditions.

BACKGROUND: We aimed to examine the anti-calcification and anti-inflammatory effects of pioglitazone as a PPAR-gamma agonist on bioprosthetic-valve-bearing aortic grafts in a rat model of diabetes mellitus (DM). METHODS: DM was induced in male Wistar rats by high-fat diet with an intraperitoneal streptozotocin (STZ) injection. The experimental group received additional pioglitazone, and controls received normal chow without STZ (n = 20 each group). Cryopreserved aortic donor grafts including the aortic valve were analyzed after 4 weeks and 12 weeks in vivo for analysis of calcific bioprosthetic degeneration. RESULTS: DM led to a significant media proliferation at 4 weeks. The additional administration of pioglitazone significantly increased circulating adiponectin levels and significantly reduced media thickness at 4 and 12 weeks, respectively (p = 0.0002 and p = 0.0107, respectively). Graft media calcification was highly significantly inhibited by pioglitazone after 12 weeks (p = 0.0079). Gene-expression analysis revealed a significant reduction in relevant chondro-osteogenic markers osteopontin and RUNX-2 by pioglitazone at 4 weeks. CONCLUSIONS: Under diabetic conditions, pioglitazone leads to elevated circulating levels of adiponectin and to an inhibition of bioprosthetic graft degeneration, including lower expression of chondro-osteogenic genes, decreased media proliferation, and inhibited graft calcification in a small-animal model of DM.

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.

[Unroofing Technique on Anomalous Aortic Origin of a Left Coronary Artery;Report of a Case].

An anomalous aortic origin of coronary artery is a cause of sudden death in young people. We report a surgical case of an anomalous aortic origin of the left coronary artery. A 16-year-old man with chest pain, which occurred while playing football, was taken in an ambulance. Electrocardiogram (ECG) revealed an ST-segment elevation in V1-V5. We performed coronary angiogram (CAG) and detected the anomalous aortic origin of left anterior descending artery. The computer tomography( CT) angiography revealed the intramural pathway of the left coronary artery. Surgery performed as an unroofing procedure for releasing the intramural portion of the left coronary artery. We confirmed a dilation of the left coronary artery ostia in postoperative coronary CT angiography. He did not have chest pain and other symptoms while cardiopulmonary exercise testing. He was discharged on the 18th postoperative day. He is seen as an outpatient without any symptoms.

Hemodynamics of a functional centrifugal-flow total artificial heart with functional atrial contraction in goats.

Implantation of a total artificial heart (TAH) is one of the therapeutic options for the treatment of patients with end-stage biventricular heart failure. There is no report on the hemodynamics of the functional centrifugal-flow TAH with functional atrial contraction (fCFTAH). We evaluated the effects of pulsatile flow by atrial contraction in acute animal models. The goats received fCFTAH that we created from two centrifugal-flow ventricular assist devices. Some hemodynamic parameters maintained acceptable levels: heart rate 115.5 ± 26.3 bpm, aortic pressure 83.5 ± 10.1 mmHg, left atrial pressure 18.0 ± 5.9 mmHg, pulmonary pressure 28.5 ± 9.7 mmHg, right atrial pressure 13.6 ± 5.2 mmHg, pump flow 4.0 ± 1.1 L/min (left) 3.9 ± 1.1 L/min (right), and cardiac index 2.13 ± 0.14 L/min/m(2). fCFTAH with atrial contraction was able to maintain the TAH circulation by forming a pulsatile flow in acute animal experiments. Taking the left and right flow rate balance using the low internal pressure loss of the VAD pumps may be easier than by other pumps having considerable internal pressure loss. We showed that the remnant atrial contraction effected the flow rate change of the centrifugal pump, and the atrial contraction waves reflected the heart rate. These results indicate that remnant atria had the possibility to preserve autonomic function in fCFTAH. We may control fCFTAH by reflecting the autonomic function, which is estimated with the flow rate change of the centrifugal pump.

[Issues in Coronary Artery Bypass Grafting for Kawasaki Disease].

Progressive narrowing at the entrance and exit of coronary artery aneurysm can develop at late phase of Kawasaki disease (KD). Evaluation and prediction of progressive coronary lesions remain a challenge in the treatment of post-KD coronary artery disease. We aimed to elucidate long-standing issues imposed on the patients who underwent coronary artry bypass grafting (CABG) for coronary artery lesions associated with KD. Between January, 2000 and December, 2013, CABG for coronary artery lesions associated with KD were performed in 6 patients (male/female: 5/1, mean age 14.5±10.0). There was no operative mortality. Follow-up for the 6 patients has been performed with the average period of 5 years (1~9 years). Cardiac events occurred in 2 patients during follow-up. In 1 patient, left internal thoracic artery (LITA) occluded due to flow competition between the native artery and LITA graft after LITA to LAD bypass grafting. The other patient required a re-do CABG using the free right internal thoracic artery to the circumflex branch because of occlusion at the coronary artery aneurysms after 4 years postoperatively. Meticulous preoperative diagnostic evaluations of coronary artery aneurysm may further improve the long-term outcome after surgical intervention for coronary lesions in conjunction with an aneurysm.

[Preoperative Use of Tolvaptan in a Patient with Constrictive Pericarditis].

Tolvaptan is a new selective vasopression V2-receptor antagonist. We report our experience with a use of tolvaptan for preoperative fluid management in a patient with severe constrictive pericarditis. A 66-year-old man presented with heart failure symptoms derived from constrictive pericarditis. Chest X-ray showed right pleural effusion and chest computed tomography demonstrated severe pericardial calcification. Despite that he received optimal conventional medical treatments, his hemodynamic condition further exacerbated during hospitalization. We administered tolvaptan in an attempt to optimize preoperative fluid management. Tolvaptan was found to be remarkably effective in that regard. The body weight decreased and the heart failure symptoms improved. Pericardiectomy was performed successfully, and he recovered uneventfully.

[Two cases of fulminant myocarditis with mesenteric ischemia].

Fulminant myocarditis (FM) can lead to a refractory cardiogenic shock and multiple organ failure. Mechanical circulatory support (MCS) is not infrequency required to salvage patients in a profound shock. Advanced technology in MCS such as a temporary ventricular assist device can yield improved early outcome. However, incessant mesenteric ischemia remains a challenge to be resolved even with MCS. We here-in report 2 cases of FM associated with mesenteric ischemia that was extremely difficult to diagnose and treat. Therapeutic strategy for FM with mesenteric ischemia is discussed.

New rat model of spinal cord infarction with long-lasting functional disabilities generated by intraspinal injection of endothelin-1.

BACKGROUND: The current method for generating an animal model of spinal cord (SC) infarction is highly invasive and permits only short-term observation, typically limited to 28 days. OBJECTIVE: We aimed to establish a rat model characterised by long-term survival and enduring SC dysfunction by inducing selective ischaemic SC damage. METHODS: In 8-week-old male Wistar rats, a convection-enhanced delivery technique was applied to selectively deliver endothelin-1 (ET-1) to the anterior horn of the SC at the Th13 level, leading to SC infarction. The Basso, Beattie and Bresnahan (BBB) locomotor score was assessed for 56 days. The SC was examined by a laser tissue blood flowmeter, MRI, immunohistochemistry, triphenyl tetrazolium chloride (TTC) staining, Western blots and TUNEL staining. RESULTS: The puncture method was used to bilaterally inject 0.7 µL ET-1 (2.5 mg/mL) from the lateral SC into the anterior horns (40° angle, 1.5 mm depth) near the posterior root origin. Animals survived until day 56 and the BBB score was stably maintained (5.5±1.0 at day 14 and 6.2±1.0 at day 56). Rats with BBB scores ≤1 on day 1 showed stable scores of 5-6 after day 14 until day 56 while rats with BBB scores >1 on day 1 exhibited only minor dysfunction with BBB scores >12 after day 14. TTC staining, immunostaining and TUNEL staining revealed selective ischaemia and neuronal cell death in the anterior horn. T2-weighted MR images showed increasing signal intensity at the SC infarction site over time. Western blots revealed apoptosis and subsequent inflammation in SC tissue after ET-1 administration. CONCLUSIONS: Selective delivery of ET-1 into the SC allows for more precise localisation of the infarcted area at the targeted site and generates a rat SC infarction model with stable neurological dysfunction lasting 56 days.

Pioglitazone treatment mitigates cardiovascular bioprosthetic degeneration in a chronic kidney disease model.

Aims: Chronic kidney disease (CKD) is a risk factor for the development of cardiovascular diseases, e.g., atherosclerosis and calcific aortic valve disease, leading inevitably to valve replacement surgery. CKD patients with bioprosthetic cardiovascular grafts, in turn, have a higher risk of premature graft degeneration. Peroxisome proliferator-activated receptor gamma (PPARγ) activation by pioglitazone has cardio-renal protective properties, and research using a heterotopic valve implantation model has shown anti-degenerative effects of PPARγ activation on bioprosthetic valved grafts (BVG) in rats. The present work aims to analyze a potential protective effect of pioglitazone treatment on BVG in an adenine-induced rat model of CKD. Methods and Results: BVG of Sprague Dawley rats were heterotopically implanted in Wistar rats in an infrarenal position for 4 and 8 weeks. Animals were distributed into three groups for each time point: 1) control group receiving standard chow, 2) CKD group receiving 0.25% adenine and 3) CKD + pioglitazone group (300 mg per kg of 0.25% adenine chow). BVG function was analyzed by echocardiography. Plasma analytes were determined and explanted grafts were analyzed by semi-quantitative real-time PCR, Western blot analysis, histology and immunohistology.PPARγ activation significantly reduced CKD-induced calcification of aortic and valvular segments of BVG by 44% and 53%, respectively. Pioglitazone treatment significantly also reduced CKD-induced intima hyperplasia by 60%. Plasma analysis revealed significantly attenuated potassium and phosphate levels after pioglitazone treatment. Moreover, PPARγ activation led to significantly decreased interleukin-6 gene expression (by 57%) in BVG compared to CKD animals. Pioglitazone treatment leads to functional improvement of BVG. Conclusion: This study broadens the understanding of the potential value of PPARγ activation in cardio-renal diseases and delineates pioglitazone treatment as a valuable option to prevent bioprosthetic graft failure in CKD. Further mechanistic studies, e.g., using small molecules activating PPARγ signaling pathways, are necessary for the evaluation of involved mechanisms. Additionally, the translation into pre-clinical studies using large animals is intended as the next research project.

[Acute Type A aortic dissection with superior mesenteric arterial dissection; report of a case].

We report a case of acute type A dissection with acute abdomen due to blood flow insufficiency in the superior mesenteric artery. A 73-year-old man was presented to hospital complaining sudden onset of chest pain. Contrast-enhanced computed tomography revealed a type A aortic dissection, that extended from the ascending aorta to the left common iliac atery. Superior mesenteric artery was compressed by the thrombosed false lumen. Epigastric pain was exacerbated acutely, we decided to treat the bowel ischemia 1st, and after that, if bowel ischemia was reversible, central repair operation performed. Emergent saphenous vein bypass was performed from the right external iliac artery to the superior mesenteric artery. Then total arch replacement was performed using cardiopulmonary bypass. The patient complicated with postoperative paralytic ileus, he completely recovered without bowel resection.

[Non-occlusive mesenteric ischemia after off-pump coronary artery bypass grafting].

Non-occlusive mesenteric ischemia( NOMI) after cardiac surgery is a rare but catastrophic complication. Although NOMI is generally recognized to be associated with extracorporeal circulation, we present a fatal case of a patient who developed NOMI after off-pump coronary artery bypass grafting (OPCAB). An 85-year-old man with left main trunk and triple vessel disease underwent OPCAB. He developed severe abdominal pain with metabolic acidosis 9 hours postoperatively. Selective angiography of the superior mesenteric artery( SMA) showed narrow and spastic branches of the SMA. A continuous intra-arterial perfusion with papaverine was started, but he died of multiple organ failure on the 3rd postoperative day. We emphasize the importance of early diagnosis and adequate treatment of NOMI including prompt exploratory laparotomy.

[Preserving autologous heart operation for ischemic cardiomyopathy].

OBJECTIVE: We report our surgical procedure (preserving autologous heart operation) for the patients with ischemic cardiomyopathy (ICM), and the results. PATIENT AND METHOD: Since May 2000, 212 patients received surgical procedure for ten years. SURGICAL PROCEDURES: We performed complete coronary artery bypass grafting (CABG), mitral surgery (plasty or replacement) for the patients with more than mild mitral regurgitation. We performed papirally muscle plication since 2005, and we performed 2nd chordal cutting since 2008, for the patients with mitral regurgitation (MR) due to severe mitral tethering. The surgical left ventricular reconstruction (SVR) was performed for the patients with dilated left ventricular. We use speckle tracking echocardiography to decide the type of the procedure of surgical left ventricular reconstruction since 2008. RESULT: Hospital death was 8.0%, and late death was 9.9%. Almost of the cause of death was congestive heart failure and ventricular arrhythmia. Five years survival was 78%, 10 years survival was 73%. CONCLUSION: The non transplant surgery for the patient with ICM was effective with the combination of CABG, mitral valve plasty (MVP) or mitral valve replacement (MVR), SVR. The size of left ventricle (LV) after SVR seemed to be a factor for late outcome of the surgery.

Valve-Sparing Root Replacement Without Cusp Repair for Regurgitant Quadricuspid Aortic Valve.

Quadricuspid aortic valve (QAV) is a relatively rare valve abnormality. Patients with aortic valve regurgitation or stenosis associated with congenital abnormalities often require surgery at a relatively young age. In most cases, patients with QAV undergo aortic valve replacement. We report on a 58-year-old patient with QAV and aortic insufficiency due to enlarged aortic root. Valve-sparing aortic root replacement was performed without any procedure on the aortic leaflets.

Less Invasive Left Ventricular Assist Device Implantation With the Furoshiki Technique.

In recent years, a less invasive approach has progressively become the first choice for left ventricular assist device (LVAD) implantation. However, in the setting of bridge to transplantation, device-related dense adhesions, particularly at the thoracotomy site, still remain a cumbersome problem at the time of heart transplantation. We propose a technique termed "Furoshiki" with the double wrapping of the LVAD at the primary less invasive implantation consisting of complete wrapping of the LVAD with expanded polytetrafluoroethylene as the first step and complete closure of the pericardial continuity with bovine pericardial patch plasty as the second step.