Bronchial artery hypertrophy-associated perioperative pulmonary hemorrhage in cardiovascular surgery: a case report.

BACKGROUND: Pulmonary hemorrhage is a life-threatening complication of cardiovascular surgery. Bronchial artery hypertrophy, a rare pathology associated with inflammatory and ischemic respiratory diseases, increases the risk of pulmonary hemorrhage; however, its involvement in cardiovascular surgery is not well known. We present two cardiovascular surgical cases in which embolization of the hypertrophied bronchial artery was effective in controlling perioperative pulmonary hemorrhage. CASE PRESENTATION: The first case was a 51-year-old man with chronic obstructive pulmonary disease who developed acute type A aortic dissection. After emergent surgery, his blood pressure suddenly dropped in the intensive care unit; computed tomography revealed a right hemothorax. Because a 4-mm dilated bronchial artery was identified on preoperative computed tomography, the hemothorax was suspected to be associated with bronchial artery hypertrophy. Selective bronchial arteriography was emergently performed and revealed a right pulmonary parenchymal blush. After subsequent coil embolization of the bronchial artery, the parenchymal blush disappeared, and his hemodynamic condition stabilized. The second case was a 66-year-old man with bronchiectasis who was referred for redo aortic valve replacement due to structural valve deterioration. A bioprosthesis was previously implanted to avoid permanent anticoagulation because the patient had repeated episodes of hemoptysis; however, he still had persistent hemosputum during admission for the redo aortic valve replacement. A dilated bronchial artery 3.7 mm in size was incidentally identified on preoperative computed tomography, and hence, the repeated hemosputum was suspected to be associated with bronchial artery hypertrophy. Bronchial arteriography revealed a right pulmonary parenchymal blush, and prophylactic embolization of the bronchial artery was performed. The hemosputum disappeared after the procedure, and redo aortic valve replacement was performed uneventfully 8 days later. CONCLUSION: In cardiovascular surgery, the risk of pulmonary hemorrhage associated with bronchial artery hypertrophy should be considered, especially in patients with inflammatory and ischemic respiratory diseases.

Combined treatment of an aortosplenic bypass followed by coil embolization in the treatment of pancreaticoduodenal artery aneurysms caused by median arcuate ligament compression: a report of two cases.

BACKGROUND: Pancreaticoduodenal artery aneurysms (PDAAs) are rare visceral aneurysms, and prompt intervention/treatment of all PDAAs is recommended at the time of diagnosis to avoid rupture of aneurysms. Herein, we report two cases of PDAA caused by the median arcuate ligament syndrome, treated with surgical revascularization by aortosplenic bypass followed by coil embolization. CASE PRESENTATION: Case 1 A 54-year-old woman presented with a chief complaint of severe epigastralgia and was diagnosed with two large fusiform inferior PDAAs and celiac axis occlusion. To preserve the blood flow of the pancreatic head, duodenum, liver, and spleen, we performed elective surgery to release the MAL along with aortosplenic bypass. At 6 days postoperatively, transcatheter arterial embolization was performed. At the 8-year 6-month follow-up observation, no recurrent perfusion of the embolized PDAAs or rupture had occurred, including the non-embolized small PDAA, and the bypass graft had excellent patency. Case 2 A 39-year-old man who had been in good health was found to have a PDAA with celiac stenosis during a medical checkup. Computed tomography and superior mesenteric arteriography showed severe celiac axis stenosis and a markedly dilated pancreatic arcade with a large saccular PDAA. To preserve the blood flow of the pancreatic arcade, we performed elective surgery to release the MAL along with aortosplenic bypass. At 9 days postoperatively, transcatheter arterial embolization was performed. At the 6-year 7-month follow-up observation, no recurrent perfusion or rupture of the PDAA had occurred, and the bypass graft had excellent patency. CONCLUSION: Combined treatment with bypass surgery and coil embolization can be an effective option for the treatment of PDAAs associated with celiac axis occlusion or severe stenosis.

L-Carnitine supplementation for the prevention of postoperative atrial fibrillation in aortic valve surgery.

OBJECTIVES: L-Carnitine, a quaternary amine, improves fatty acid metabolism in the heart and has anti-inflammatory effects. Several studies have reported the efficacy of L-carnitine for the prophylaxis of arrhythmia. We assessed the clinical effectiveness of L-carnitine in preventing postoperative atrial fibrillation (POAF) in aortic valve surgery. METHODS: Thirty patients who underwent aortic valve surgery were included. Fifteen patients had no prophylaxis other than conventional measures (control), while 15 patients received oral L-carnitine for 9 days (daily dose of 3 g). The incidence of POAF during 1 week after surgery was compared between the two groups. The multivariable logistic regression analysis for POAF was performed using the pre- and intraoperative parameters. RESULTS: Preoperative characteristics and operative data were comparable between the groups. The POAF rate was significantly lower in the L-carnitine group than in the control (20% and 60%, respectively; P = 0.025). L-Carnitine use was an independently negative predictor for POAF (odds ratio 0.067; 95% confidence interval 0.006-0.768). CONCLUSIONS: L-Carnitine administration may have potential for the prevention of POAF in aortic valve surgery.

Correlation between increased atrial expression of genes related to fatty acid metabolism and autophagy in patients with chronic atrial fibrillation.

Atrial metabolic disturbance contributes to the onset and development of atrial fibrillation (AF). Autophagy plays a role in maintaining the cellular energy balance. We examined whether atrial gene expressions related to fatty acid metabolism and autophagy are altered in chronic AF and whether they are related to each other. Right atrial tissue was obtained during heart surgery from 51 patients with sinus rhythm (SR, n = 38) or chronic AF (n = 13). Preoperative fasting serum free-fatty-acid levels were significantly higher in the AF patients. The atrial gene expression of fatty acid binding protein 3 (FABP3), which is involved in the cells' fatty acid uptake and intracellular fatty acid transport, was significantly increased in AF patients compared to SR patients; in the SR patients it was positively correlated with the right atrial diameter and intra-atrial electromechanical delay (EMD), parameters of structural and electrical atrial remodeling that were evaluated by an echocardiography. In contrast, the two groups' atrial contents of diacylglycerol (DAG), a toxic fatty acid metabolite, were comparable. Importantly, the atrial gene expression of microtubule-associated protein light chain 3 (LC3) was significantly increased in AF patients, and autophagy-related genes including LC3 were positively correlated with the atrial expression of FABP3. In conclusion, in chronic AF patients, the atrial expression of FABP3 was upregulated in association with autophagy-related genes without altered atrial DAG content. Our findings may support the hypothesis that dysregulated cardiac fatty acid metabolism contributes to the progression of AF and induction of autophagy has a cardioprotective effect against cardiac lipotoxicity in chronic AF.

Persistent Fifth Aortic Arch With Left Ventricular Dysfunction and Left Bronchial Obstruction.

Persistent fifth aortic arch (AA) is a rare anomaly in congenital heart disease, which is often associated with aortic obstructive diseases. We report a 7-month-old infant diagnosed with persistent fifth AA with left ventricular dysfunction along with left bronchial malacia due to compression from their own heart. Surgical repair was performed, including AA reconstruction using the fifth AA as an in situ flap to enlarge the fourth AA with end-to-end anastomosis, and external stenting for the left bronchial malacia. Postoperative courses were uneventful. On computed tomography, a reconstructed AA without obstruction and an expanded left bronchus were seen.

Refractory Right Ventricular Failure in a Patient with Emery-Dreifuss Muscular Dystrophy.

A 23-year-old man had progressive muscle weakness and Emery-Dreifuss muscular dystrophy (EDMD) due to a LMNA (lamin A/C) mutation. Congestive heart failure diagnosed at 19 years of age. Maximal drug treatment/cardiac resynchronization failed to improve the cardiac function. He was therefore hospitalized due to heart failure. Despite extracorporeal membrane oxygenation, he developed severe right heart dysfunction and died (multiple organ failure). A cardiac lesion's presence determines the prognosis of EDMD. While there are many arrhythmia reports, few reports on heart failure (particularly severe heart failure requiring cardiac transplantation) have been published. Right heart function monitoring and early ventricular-assist device use plus right heart support considering heart transplantation are important.

Perioperative changes of the slope in the preload recruitable stroke work relationship by a single-beat technique after mitral valve surgery in functional mitral regurgitation with non-ischemic dilated cardiomyopathy.

OBJECTIVES: The slope in the preload recruitable stroke work relationship is a highly linear, load-insensitive contractile parameter. However, the perioperative change of the slope has not been reported before. We examined the perioperative slope from a steady-state single beat in patients with functional mitral regurgitation and assessed the correlation with brain natriuretic peptide (BNP) levels. METHODS: The study included 16 patients with non-ischemic dilated cardiomyopathy and refractory heart failure: 10 patients underwent mitral valve plasty and left ventricular plasty (MVP + LVP group) and 6 patients who underwent mitral valve replacement and papillary muscle tugging approximation (MVR + PMTA group). The left ventricular ejection fraction was assessed by the modified Simpson method; the slope was assessed by the single-beat technique using transthoracic echocardiography. BNP levels were measured by chemiluminescent immunoassay. RESULTS: The left ventricular ejection fraction and slope did not significantly change from pre- to early post-surgery in the MVP + LVP group. Both the left ventricular ejection fraction and slope significantly increased 6 months after surgery in the MVR + PMTA group. Postoperative BNP level was low in the MVR + PMTA group. While the postoperative left ventricular ejection fraction did not correlate with BNP levels, the postoperative slope significantly correlated with BNP level after surgery in the MVP + LVP group and in the total functional mitral regurgitation group. CONCLUSIONS: The change of slope was dependent on surgical procedures. In functional mitral regurgitation, the slope may be a more sensitive parameter in reflecting the left ventricular contractile function than the left ventricular ejection fraction.

Risk factors for residual mitral regurgitation after aortic valve replacement in patients with severe aortic valve stenosis and moderate mitral regurgitation.

OBJECTIVES: While it was reported that patients with residual moderate mitral regurgitation (MR) after surgical aortic valve replacement (SAVR) had a poorer prognosis than those without it, the risk factors for residual MR have not been fully elucidated. The aim of the study was to evaluate risk factors for residual MR after SAVR. METHODS: Of the 222 patients who underwent isolated SAVR from 2001 to 2018, 33 (11 men; age: 74 ± 7 years) had functional moderate MR before surgery. The risk factors for residual MR were evaluated by comparing patients with residual moderate MR (n = 11, 33%) with those who exhibited improved post-surgery MR (n = 22, 67%). RESULTS: The left atrial diameter was significantly larger in the residual MR group (51 ± 7 mm) than in the improved MR group (46 ± 5 mm; P = 0.049). The mean pressure gradient at the aortic valve was significantly smaller in the residual MR group (52 ± 18 mmHg) than in the improved MR group (69 ± 22 mmHg; P = 0.043). A ratio of left atrial diameter (mm) and mean aortic valve pressure gradient (mmHg) greater than 0.9 predicted residual MR with a sensitivity of 70% and a specificity of 74% (area under the ROC curve: 0.779; P = 0.015). CONCLUSIONS: In patients with severe aortic valve stenosis and moderate MR, a high ratio of preoperative left atrial diameter and mean aortic valve pressure gradient would be a parameter predicting residual moderate MR post-SAVR.

Impaired mitochondrial oxidative phosphorylation capacity in epicardial adipose tissue is associated with decreased concentration of adiponectin and severity of coronary atherosclerosis.

Epicardial adipose tissue (EAT), a source of adipokines, is metabolically active, but the role of EAT mitochondria in coronary artery disease (CAD) has not been established. We investigated the association between EAT mitochondrial respiratory capacity, adiponectin concentration in the EAT, and coronary atherosclerosis. EAT samples were obtained from 25 patients who underwent elective cardiac surgery. Based on the coronary angiographycal findings, the patients were divided into two groups; coronary artery disease (CAD; n = 14) and non-CAD (n = 11) groups. The mitochondrial respiratory capacities including oxidative phosphorylation (OXPHOS) capacity with non-fatty acid (complex I and complex I + II-linked) substrates and fatty acids in the EAT were significantly lowered in CAD patients. The EAT mitochondrial OXPHOS capacities had a close and inverse correlation with the severity of coronary artery stenosis evaluated by the Gensini score. Intriguingly, the protein level of adiponectin, an anti-atherogenic adipokine, in the EAT was significantly reduced in CAD patients, and it was positively correlated with the mitochondrial OXPHOS capacities in the EAT and inversely correlated with the Gensini score. Our study showed that impaired mitochondrial OXPHOS capacity in the EAT was closely linked to decreased concentration of adiponectin in the EAT and severity of coronary atherosclerosis.

Re-do mitral valve replacement for a bioprosthetic valve with central transvalvular leakage in a patient with ischemic cardiomyopathy: a case report.

Transvalvular leakage (TVL) of a prosthetic heart valve is not negligible regurgitant flow in patients with critically low contractile function. Although the opening function of prosthetic valves has been reported, its closing function is not well understood. A man in his 70 s had a history of mitral valve replacement (MVR) with a Magna Mitral® valve for ischemic mitral valve regurgitation. He presented with dyspnea 2 years postoperatively. Echocardiography showed moderate TVL. The pulmonary capillary wedge pressure and cardiac index were 37 mmHg and 1.65 L/min/m2, respectively. Because we considered his TVL relevant, we performed re-do MVR with a mechanical valve and papillary muscle approximation and suspension ("papillary muscle tugging approximation"). His cardiac function improved postoperatively; he was discharged with New York Heart Association class I. For MVR in patients with critically low contractile function, prosthetic valves, such as mechanical valves, with small TVL are recommended.

Papillary Muscle Tugging Approximation for Functional Mitral Regurgitation.

The surgical approach is challenging for patients with severe functional mitral regurgitation with nonischemic/ischemic dilated cardiomyopathy who are unsuitable for heart transplantation or ventricular assist device implantation. We developed a new surgical treatment named papillary muscle tugging approximation combined with mitral valve replacement. This technique is safe and feasible, with excellent midterm outcomes.

Mechanical properties of a new thermally deformable mitral valve annuloplasty ring and its effects on the mitral valve.

Ideally, an annuloplasty ring's shape should be changed intraoperatively if mitral valve repair is unsuccessful because of a short coaptation length or systolic anterior motion. Several post-implantation adjustable rings have been developed, but they are not freely deformable and are unsuitable for asymmetric repair of the valvular annulus. We developed a novel thermally deformable mitral annuloplasty ring to address these problems and assessed the ring's mechanical properties and its effect on the mitral valve anatomy. This ring was made of polycaprolactone. Tensile and bending tests were performed to evaluate the ring's mechanical properties. The ratio of the transverse and septal-lateral length was determined as 4:3. Using 10 pig hearts, we measured the post-deformation coaptation length and minimum distance from the coaptation to the ventricular septum, which is a factor of abnormal systolic anterior motion of the mitral valve. In the mechanical tests, the ring's yield point was greater than the deformation force of the annulus in humans. In pigs with deformation from "4:3" to "4:2", the coaptation length was significantly increased in each mitral valve part. In pigs with deformation from "4:3" to "4:4", the minimum distance from the coaptation to the ventricular septum was significantly increased. Asymmetrical ring deformation increased the coaptation length only at the deformed area. In conclusion, this new thermally deformable mitral annuloplasty ring could be "order-made" to effectively change the coaptation length in all parts of the mitral valve and the distance from the coaptation to septum post-deformation via intraoperative heating.

[Surgical Options for Refractory Heart Failure Patients with Non-ischemic Dilated Cardiomyopathy].

Surgical strategy for non-ischemic dilated cardiomyopathy (NIDCM) is currently controversial. Subjects were 20 patients who underwent left ventriculoplasty(LVP) from 2006 to 2013 and 6 patients who underwent papillary muscle tugging approximation (PMTA) after 2015. PMTA is a new trans-mitral approach combined with valve replacement without left ventriculotomy. Another group of patients( n=14)who were registered for heart transplantation( HTx) after 2013 was also analyzed for left ventricular assist device(LVAD) free survival. Mw( slope in the preload recruitable stroke work relationship) calculated by single beat technique using echocardiography was employed as a load-independent cardiac functional parameter. The baseline characteristics and Mw were not different between the LVP and PMTA groups. One-year survival was significantly lower in the LVP group(53%)than in the PMTA group(100%)[log-rank:p=0.024]. In the HTx group, early LVAD implantation was necessary in the patients who had low Mw(<20)at the time of registration. In conclusion, PMTA would be one option for NIDCM patients( non-HTx candidates) with severe mitral regurgitation. Early LVAD implantation might be predicted in HTx candidates with low Mw(<20).

Anticoagulation management during cardiopulmonary bypass in patients with antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is a complex autoimmune disease often related to systemic lupus erythematosus. Although adequate anticoagulation is important for APS patients during cardiopulmonary bypass, clotting tests can be potentially misleading due to antiphospholipid antibodies. We performed cardiac surgery safely in two APS patients under anticoagulation monitoring determined using preoperative heparin titration. We performed heparin titration for activated clotting time to determine the appropriate heparin concentration during cardiac surgery. We changed the targeted heparin concentration considering each patient's thrombotic risks: 3 U/ml of heparin for a normal-risk APS patient and 5 U/ml for a high-risk APS patient with a history of antiphospholipid-antibody-associated thrombocytopenia. A higher targeted heparin concentration might be necessary for patients with high thrombotic risks.

Surgery for Left Ventricular Outflow Tract Obstruction with a Relatively Thin Interventricular Septum.

BACKGROUND: To examine the results of myectomy and mitral valve surgery for systolic anterior motion (SAM) of the mitral valve and left ventricular outflow tract obstruction (LVOTO) with a relatively thin interventricular septum. METHODS: The subjects were 12 patients with SAM and LVOTO. Eight had hypertrophic obstructive cardiomyopathy (HOCM) with a mean interventricular septal thickness of 16 mm. Three had sigmoid septum and one had an unknown etiology. For HOCM, isolated extended myectomy was performed when mitral regurgitation was mild (n = 1) and extended myectomy plus mitral valve surgery was performed when mitral regurgitation was more than mild (n = 4) or primary valve etiologies existed (n = 3). Myectomy was performed for the three cases with sigmoid septum. Myectomy plus height reduction of the posterior mitral leaflet was performed for the one case with the unknown etiology of SAM. RESULTS: In the patients with HOCM, the maximum LVOT pressure gradient significantly decreased from 140 ± 18 to 16 ± 6 and 3 ± 3 mm Hg, while mitral regurgitation significantly decreased from 2.3 ± 0.5 to 0.5 ± 0.3 and 0.4 ± 0.2 at pre-op, early post-op, and last follow-up (3 ± 1 years), respectively. In the other etiologies, the maximum LVOT pressure gradient changed from 56 ± 15 to 25 ± 15 and 5 ± 4 mm Hg; mitral regurgitation changed from 2.0 ± 0.6 to 1.3 ± 0.3 and 1.3 ± 0.8, at pre-op, early post-op, and the last follow-up (3 ± 2 years), respectively. CONCLUSION: Myectomy with mitral valve surgery is an option for SAM and LVOTO in patients with a relatively thin interventricular septum.

Decreased gene expression of fatty acid binding protein 3 in the atrium of patients with new onset of atrial fibrillation in cardiac perioperative phase.

BACKGROUND: Post-operative atrial fibrillation (POAF) frequently occurs after cardiac surgery. However, the mechanisms of POAF have not been fully elucidated. We aimed to examine whether pre-operative atrial gene expression related to cardiac metabolism is changed in patients with POAF. METHODS: Right atrial tissue was obtained during surgery from 38 patients who underwent cardiac surgery from 2013 to 2015. Atrial expression levels were determined by reverse transcription polymerase chain reaction for the following genes: glucose transporter type 4, peroxisome proliferator-activated receptor-α, fatty acid translocase, carnitine palmitoyltransferase 1B, and fatty acid binding protein 3 (FABP3). To investigate fatty acid ß-oxidation and tricarboxylic acid cycle capacities in the mitochondria, ß-hydroxyacyl CoA dehydrogenase and citrate synthase activity levels were spectrophotometrically determined. RESULTS: POAF within 7 days after surgery was observed in 18 (47%) patients. POAF patients were significantly older, had a larger left atrial diameter, and had reduced expression of FABP3, a fatty acids transport gene in the cytosol, compared to those in the non-POAF group. Reduced FABP3 expression predicted POAF independent of age and atrial size. In contrast, fatty acid ß-oxidation enzymatic activity was comparable between the groups. CONCLUSIONS: FABP3 gene expression in the atrium was reduced in patients with POAF. These findings suggest a potential link between altered fatty acid transport in the atrium and increased AF onset after cardiac surgery.

Feasibility and limitations of mitral valve repair, with or without left ventricular reconstruction in non-ischemic dilated cardiomyopathy.

BACKGROUND: Although non-transplant surgical interventions for non-ischemic dilated cardiomyopathy (NIDCM) are relatively effective, their feasibility and limitations have not been fully elucidated. The aim of this study was to define the feasibility and limitations of mitral valve repair, with or without surgical ventricular reconstruction for patients with NIDCM in terms of postoperative low cardiac output syndrome (LOS). METHODS: Twenty non-transplant candidates (aged 57±13 years) with NIDCM and significant mitral regurgitation had undergone mitral valve repair combined with submitral procedures. Using a 72-mL plastic ellipsoidal sizer, left ventricular reconstruction was performed concomitantly in 14/20 (70%) patients with extremely large ventricles. Total stroke volume, deceleration time of early trans-mitral flow wave, and the slope (Mw) in the preload recruitable stroke-work relationship were assessed using transthoracic echocardiography. LOS was defined as in-hospital death due to heart failure or a cardiac index less than 2.2L/min/m2 before discharge. RESULTS: There were three in-hospital deaths and four patients with postoperative cardiac index less than 2.2L/min/m2 [n=7 (35%), LOS group]. Preoperative total stroke volume, deceleration time, and the Mw were significantly lower in the LOS group compared to those in the non-LOS group; the predicted cut-off values for LOS were 84mL/beat (p=0.008), 133ms (p=0.015), and 45ergcm-3×103 (p=0.036), respectively. Preoperative left ventricular ejection fraction and ventricular size could not predict postoperative LOS. The one-year survival rate was 0% in the LOS group and 84% in the non-LOS group (p<0.001). CONCLUSIONS: Mitral valve repair, with or without left ventricular reconstruction, could be contraindicated for NIDCM patients with low total stroke volume, deceleration time, and Mw in terms of high postoperative incidence of LOS. For high-risk patients, other therapeutic strategies might be necessary.

Left-Ventricular Plication Reduces Wall Stress and Cardiomyocyte Hypertrophy in a Rat Model of Ischemic Cardiomyopathy.

BACKGROUND: The indications of left-ventricular plication (LVP) are controversial, although several studies have reported favorable outcomes in heart failure patients. The aim of this study was to assess left-ventricular (LV) wall stress and myocardial remodeling after LVP in a rat model of myocardial infarction (MI). METHODS: Sixteen rats underwent LVP by excluding the LV anterior wall scar 4 weeks after ligation of the left anterior descending artery. After 4 weeks, LV wall stress was assessed using transthoracic echocardiography and an LV catheter. Gene expression of the wall stress markers, atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP), were evaluated via reverse transcription polymerase chain reaction. Cardiomyocyte area and myocardial fibrosis were also examined through histological examinations. These parameters were compared to those in 16 rats that underwent coronary artery ligation but not LVP. RESULTS: We noted that the LV end-diastolic dimension was smaller (9.9 ± 0.3 vs. 11.2 ± 0.2 mm, p < 0.05) and fractional shortening was greater (25 ± 2 vs. 15 ± 1%, p < 0.05) in LVP rats than in sham rats. Moreover, systolic wall stress was lower in LVP rats (71 ± 7 vs. 111 ± 9 × 103 dyn/cm2, p < 0.05). Myocardial ANF and BNP expression levels were lower in LVP rats (2.6 ± 0.3 vs. 4.4 ± 0.5 and 1.0 ± 0.1 vs. 1.5 ± 0.2 arbitrary units, respectively; p < 0.05). Cardiomyocyte area was significantly decreased in LVP rats (556 ± 15 vs. 670 ± 28 µm2, p = 0.003) and was correlated with LV wall stress (r = 0.669, p = 0.002). The reduction in myocardial fibrosis after LVP was not significant. CONCLUSION: LVP reduced LV wall stress and cardiomyocyte hypertrophy in a rat model of MI.