Akimasa Morisaki

Risk Factor Analysis in Patients With Liver Cirrhosis Undergoing Cardiovascular Operations

BACKGROUND Variable outcomes of cardiac operations have been reported in cirrhotic patients, but no definitive predictive prognostic factors have been established. This retrospective study assessed operative results to identify risk factors associated with morbidity after cardiovascular operations in cirrhotic patients. METHODS The study comprised 42 cirrhotic patients who underwent cardiovascular operations from January 1991 to January 2009. Thirty patients were Child-Turcotte-Pugh class A, and 12 were class B. Hospital morbidity occurred in 13 patients (31.0%; M group), including 4 who died in-hospital. Patients without severe complications (N group) were compared with the M group patients. The Model for End-Stage Liver Disease (MELD) score was evaluated in 25 patients. RESULTS Significant differences in hospital morbidity between the M vs N groups were identified for platelet count (8.7 +/- 3.8 vs 12.1 +/- 4.2 x 10(4)/microL), MELD score (17.8 +/- 5.3 vs 9.8 +/- 4.9), operation time (370 +/- 88 vs 313 +/- 94 minutes), and cardiopulmonary bypass time (174 +/- 46 vs 149 +/- 53 minutes) in univariate analyses (p < 0.005). Platelet count, operation time, and age were significantly associated with hospital morbidity in multivariate analyses (p < 0.005). Platelet count of 9.6 x 10(4)/microL and MELD score of 13 were cutoff values for hospital morbidity. CONCLUSIONS Careful consideration of operative indications and methods are necessary in cirrhotic patients with low platelet counts or high MELD scores. A high incidence of hospital morbidity is predicted in patients with platelet counts of less than 9.6 x 10(4)/microL or MELD scores exceeding 13.

Evaluation of risk factors for hospital mortality and current treatment for poststernotomy mediastinitis.

PurposePoststernotomy mediastinitis (PSM) following cardiovascular surgery remains an intractable complication associated with considerable mortality. It is therefore necessary to assess the risk factors associated with hospital mortality and evaluate the surgical treatment options for PSM.MethodsWe identified 59 (2.2%) patients who developed PSM after cardiovascular surgery between January 1991 and January 2010. PSM was defined as deep sternal wound infection requiring surgical treatment. In all, 31 patients were infected with methicillin-resistant Staphylococcus aureus (MRSA); and 14 patients died in hospital from PSM. A total of 51 patients were treated by simple closure or tissue flap reconstruction after débridement (traditional treatment), and 8 underwent closure or reconstruction after negative-pressure wound therapy (NPWT). The risk factors for in-hospital mortality due to PSM were analyzed by comparing the characteristics of survivors and nonsurvivors. The available surgical treatments for mediastinitis were also assessed.ResultsUnivariate analysis identified age, sex, pulmonary disease, MRSA infection, prolonged mechanical ventilation and prolonged intensive care unit stay as risk factors for in-hospital mortality (P < 0.05). Multiple logistic regression analysis identified MRSA infection (odds ratio 20.263, 95% confidence interval 1.580–259.814; P = 0.0208) as an independent risk factor for hospital mortality. NPWT was associated with significantly less surgical failure than traditional treatment (P = 0.0204). There were no deaths as a result of PSM in patients who underwent NPWT irrespective of the presence of MRSA infection.ConclusionMRSA infection was an independent risk factor for PSM-related in-hospital mortality. NPWT may improve the prognosis for patients with MRSA mediastinitis.

Mitral valve repair for atrial functional mitral regurgitation in patients with chronic atrial fibrillation

OBJECTIVES Atrial functional mitral regurgitation (MR) has been recently described in patients with chronic atrial fibrillation (AF). However, the results of surgical mitral valve (MV) repair for this type of MR have not been comprehensively reported. Our study aimed to address this deficiency. METHODS We retrospectively studied 10 chronic AF patients who underwent MV repair for atrial functional MR with normal left ventricular dimension and preserved left ventricular systolic function. All patients had chronic heart failure (HF) symptoms and at least one prior admission for HF complicated by severe MR. RESULTS Ring annuloplasty was performed in all patients; the median ring size was 26 mm (range, 26-30 mm). Concomitant tricuspid valve repair was undertaken in all patients. Preoperatively, left atrial (LA) diameter on the parasternal long-axis view, LA volume index and mitral annular diameter were 52 ± 9 mm, 72 ± 26 ml/m(2) and 33 ± 4 mm, respectively. There was no mortality and no re-admission due to HF during follow-up (range, 10-52 months). MR at the most recent examination was mild or improved in degree in all patients. The LA volume index decreased from the preoperative period, measuring 48 ± 17 ml/m(2) at the most recent period (P = 0.03). The New York Heart Association functional class dramatically improved from the preoperative period to the most recent period (from 3.0 ± 0.7 to 1.2 ± 0.4, P < 0.0001). CONCLUSIONS Our results suggest that MV repair leads to reductions in MR, LA size and HF symptoms, and that it may prevent future HF events in patients with atrial functional MR.

Cardiotomy suction, but not open venous reservoirs, activates coagulofibrinolysis in coronary artery surgery

OBJECTIVES Closed and miniaturized cardiopulmonary bypass circuits, which eliminate cardiotomy suction and open venous reservoirs with a reduced priming volume, have been reported to be advantageous. We comparatively examined the respective contribution of cardiotomy suction and open venous reservoirs to perioperative activation in coagulofibrinolysis and inflammation systems, with identical conditions of priming volume and anticoagulation. METHODS A total of 75 consecutive coronary artery bypass grafting procedures were performed using 1 of the following 3 cardiopulmonary bypass circuits under identical conditions of priming volumes, heparin coating, and protocols of anticoagulation and transfusion, as follows: a circuit with an open venous reservoir and cardiotomy suction (open group, n = 25), a circuit with an open venous reservoir without cardiotomy suction (nonsuction group, n = 25), or a circuit without either (closed group, n = 25). Blood samples were collected at 8 points up to the first postoperative morning. RESULTS The thrombin-antithrombin III complex, fibrinogen degeneration products, D-dimer, plasmin-α2 plasmin inhibitor complex, and plasminogen activator inhibitor-1 levels were significantly greater in the open group than those in the other 2 groups (P < .0001, for all markers). The C3a and interleukin-6 levels were similar among all the groups. The incidences of perioperative transfusion and postoperative bleeding were increased and the early graft patency rate of saphenous veins was lower in the open group than those in the other 2 groups. CONCLUSIONS Cardiotomy suction, but not open venous reservoirs, causes perioperative coagulofibrinolysis activation, although neither affects the inflammation system. The use of cardiotomy suction needs to be examined further in association with postoperative PAI-1 elevation and early vein graft occlusion.

Effect of negative pressure wound therapy followed by tissue flaps for deep sternal wound infection after cardiovascular surgery: propensity score matching analysis

OBJECTIVES Deep sternal wound infection (DSWI) after cardiovascular surgery via median sternotomy remains a severe complication associated with a drastic decrease in the quality of life. We assessed the risk factors for in-hospital death caused by DSWI and the available treatments for DSWI. METHODS Between January 1991 and August 2015, we retrospectively reviewed 73 patients (51 males and 22 females, mean age 67.5 ± 10.3 years) who developed DSWI after cardiovascular surgery via median sternotomy. Pathogenic bacteria mainly comprised methicillin-resistant Staphylococcus aureus (MRSA) (49.3%). Fifteen patients (20.5%) died in hospital with DSWI. Treatment of DSWI consisted of open daily irrigation (up to 2006) or negative pressure wound therapy (NPWT) (2007 onwards), followed by primary closure or reconstruction of tissue flaps. We assessed the risk factors for in-hospital mortality from DSWI by comparing data from the 15 patients who died and the 58 survivors using propensity score matching analysis of the treatments used for DSWI. RESULTS Univariate analysis identified age, use of intra-aortic balloon pumping, prolonged mechanical ventilation, tracheotomy, prolonged intensive care unit stay, postoperative low output syndrome, postoperative myocardial infarction, postoperative renal failure, postoperative use of haemodialysis, postoperative pneumonia, postoperative cerebral disorder, MRSA infection, NPWT and tissue flaps as being associated with in-hospital mortality (P < 0.05). Multivariate analysis identified NPWT (odds ratio, 0.062; 95% confidence interval, 0.004-0.897; P = 0.041) and tissue flaps (odds ratio, 0.022; 95% confidence interval, 0.000-0.960; P = 0.048) as independently associated with reduced in-hospital mortality after DSWI. On comparing 22 patients receiving NPWT with 22 not on NPWT using propensity score matching, patients on NPWT had significantly lower in-hospital mortality than those without NPWT (NPWT vs non-NPWT, 5 vs 36%, P = 0.021). In DSWI infected by MRSA, NPWT significantly reduced the in-hospital mortality caused by DSWI (NPWT vs non-NPWT, 0 vs 52%, P = 0.003). CONCLUSIONS NPWT and tissue flaps may be favourable factors associated with reduced in-hospital mortality attributable to DSWI. NPWT as a bridge therapy to tissue flaps may play a major role in treating DSWI and improve the prognosis for patients with MRSA-infected DSWI.

Mitral valve repair with loop technique via median sternotomy in 180 patients

OBJECTIVES Artificial chordal reconstruction technique uses several expanded polytetrafluoroethylene loops to achieve mitral valve repair. METHODS We studied retrospectively 180 patients who underwent mitral valve repair using the loop technique via median sternotomy: 86 for posterior leaflet prolapse, 48 for anterior leaflet prolapse and 26 for bileaflet prolapse. RESULTS Of the 180 patients, 138 required 1 loop set; 40 patients required 2 and 2 patients with Barlows disease required 3. Loop sets contained two to nine loops ranging in length from 14 to 26 mm. Additional techniques required to ensure complete repair using the loop technique included commissural edge-to-edge suture in 78 patients, loop-in-loop technique for extension of the artificial loop in 18 and use of needle-side sutures in 18. Systolic anterior leaflet motion was observed in only 2 patients (1.1%). One patient with immune deficiency died of sepsis. Predischarge echocardiograms showed no or trace mitral regurgitation (MR) in 160 patients (89%), mild MR in 17 patients (9.4)% and mild-to-moderate MR in 3 patients (1.7%). Only 1 patient required redo operation due to recurrent MR freedom from MR greater than moderate was seen in 98.0 ± 1.4% of patients at 1 year, 91.5 ± 2.8% of patients at 3 years, and 91.5 ± 2.8% at 5 years postoperatively. No significant difference was seen in the rate of recurrence of MR among the sites of prolapsing leaflets. CONCLUSIONS The loop technique via median sternotomy to treat posterior, anterior and, especially, bileaflet prolapse provided satisfactory mid-term outcomes.

Less-Invasive Endovascular Treatment of Arch Aneurysm With Aberrant Right Subclavian Artery

We report a patient with an arch aneurysm with an aberrant right subclavian artery who underwent successful endovascular treatment with the chimney technique and bilateral carotid artery-to-subclavian artery bypasses. We used a chimney graft in the left carotid artery to preserve its flow. The bilateral carotid-to-subclavian artery bypasses preserved perfusion of the bilateral vertebral arteries. A thoracic stent graft was subsequently deployed in the aortic arch over the chimney graft of the left carotid artery. There have been few reports about less-invasive treatment for arch aneurysm with aberrant right subclavian artery. This technique was an effective strategy to avoid a high-risk open operation.

Evaluation of Aortic Valve Replacement via the Right Parasternal Approach without Rib Removal

BACKGROUND Although right parasternal approach (RPA) decreases the incidence of mediastinal infection, this approach is associated with lung hernia and flail chest. Our RPA employs thoracotomy with bending rib cartilages and wound closure performed by repositioning the ribs with underlying sheet reinforcement. METHODS We evaluated 16 patients who underwent aortic valve replacement via the RPA from January 2010 to August 2013. We compared outcomes of 15 male patients had the RPA with 30 male patients had full median sternotomy. RESULTS One patient with a history of radical breast cancer treatment underwent RPA with concomitant right coronary artery bypass grafting. No hospital deaths occurred. Four patients developed hospital-associated morbidity (re-exploration for bleeding, prolonged ventilation, cardiac tamponade, and perioperative myocardial infarction). There were no conversions to full median sternotomy, mediastinal infections, and lung hernias. Preoperative computed tomography showed that the distance from the right sternal border to the aortic root was significantly associated with operation times. With RPA, there was no significant difference in outcomes, despite significantly longer operation times compared with full median sternotomy. CONCLUSION Our RPA provides satisfactory outcomes without lung hernia, especially in patients unsuitable for sternotomy. Preoperative computed tomography is useful for identifying appropriate candidates for the RPA.

Mitral valve repair without mitral annuloplasty with extensive mitral annular calcification

In mitral valve repair, removal of mitral annular calcification (MAC) is necessary to secure the artificial ring but may cause rupture of the left ventricle or injury to the circumflex coronary artery. We experienced 3 cases of mitral valve regurgitation with extensive MAC. Patient 1, an 83-year old woman, had P1-P2 prolapse due to tendon rupture. We performed mitral valve repair with triangular resection of P2 and patch reconstruction, artificial-chordal reconstruction to P2 and anterolateral commissural edge-to-edge suturing. Patient 2 was a 76-year old man with P3 prolapse due to tendon rupture. We performed A3-P3 edge-to-edge suturing and small annular plication of the posteromedial commissure. Patient 3, an 84-year old woman with a non-specific coaptation defect in the anterolateral commissure and tenting of the anterior mitral leaflet due to a secondary chorda, underwent cutting of the secondary chorda of the anterior mitral leaflet and A1-P1 edge-to-edge suturing. We performed tricuspid annuloplasty in Patient 1 and aortic valve replacement in Patients 2 and 3. Postoperative echocardiography showed good control of mitral valve regurgitation, which we were able to regulate by repairing the leaflets and chordae without decalcification of the mitral annulus or implantation of an artificial ring.

Aortoesophageal Fistula after Endovascular Repair for Aberrant Right Subclavian Artery Aneurysm

A 76-year-old woman with malignant rheumatic arthritis developed dysphagia and hoarseness secondary to an aberrant right subclavian artery aneurysm. We performed a hybrid endovascular repair with concomitant surgical treatment for the aberrant right subclavian artery aneurysm. One month after discharge, she was emergently admitted to our hospital because of chest pain and fever. We diagnosed aortoesophageal fistula and stent graft infection based on computed tomography, gallium scintigraphy, and esophagoscopy results. Esophagectomy, elimination of the infected stent graft, and muscle plombage were performed during several surgeries. However, she died of hemorrhagic shock secondary to an aortobronchial fistula.