Masayuki Sakaki

Influences of nonpulsatile pulmonary flow on pulmonary function: Evaluation in a chronic animal model

To clarify the influences of nonpulsatile blood flow on the physiologic function of the lung, we established nonpulsatile pulmonary circulation with a centrifugal pump in a chronic animal model (adult goats, n = 6). As the initial phase, a pulsatile right ventricular assist device was implanted to bypass the whole blood supply from both the right atrium and right ventricle to the pulmonary artery. After 2 weeks of pumping, the pulsatile pump was replaced with a centrifugal pump without anesthesia, and nonpulsatile pulmonary circulation was instituted. In this experimental model, no significant change was observed in either mean pulmonary arterial pressure or pulmonary vascular resistance index during the pulsatile pumping compared with that on the fourteenth day of nonpulsatile pumping. Blood gas data, extravascular lung water content, and serum level of angiotensin-converting enzyme were maintained within normal ranges. There was also no significant change in the ventral to dorsal blood perfusion ratio of the lower lobe of the right lung. These results indicate that pulmonary functions are not affected by nonpulsatile pulmonary circulation for a period of 14 days in this animal model.

Thyroid carcinoma with extensive tumor thrombus in the atrium.

To our knowledge, only a few cases of thyroid carcinoma with an extensive tumor thrombus in the atrium have been reported in literature. We describe a unique case of papillary carcinoma of the thyroid with extensive tumor thrombus in the atrium. A 74-year-old man consulted our hospital because of thyroid carcinoma with an extensive tumor thrombus in the atrium. Computed tomography (CT) revealed a 2-cm tumor with extensive continuous tumor thrombus in the left jugular vein, innominate vein, superior vena cava, and atrium. The tumor was resected to reduce the risk of sudden death from tumor embolism into the pulmonary arteries. Histologically, the diagnosis was papillary carcinoma of the thyroid. Thyroid carcinoma, especially papillary carcinoma, rarely develops a macroscopic tumor thrombus. Patients with an extensive tumor thrombus generally have poor prognoses and high mortality. This patient has been followed for 7 months after successful operation without recurrence.

Use of quantitative analysis of remote myocardial fibrosis with delayed-enhancement magnetic resonance imaging to predict outcomes after surgical ventricular restoration for ischemic cardiomyopathy

OBJECTIVE Preserved myocardial function remote from surgical site is crucial for good outcome after surgical ventricular restoration in ischemic cardiomyopathy. We hypothesized that left ventricular scarring untouched by operation would negatively affect postoperative outcome. METHODS In 15 consecutive patients (mean age 61 +/- 12 years, mean left ventricular ejection fraction 20% +/- 7.5%), left ventricular assessments by magnetic resonance imaging and right heart catheterization were performed before and after operation. Left ventricular basal scarring remote from surgical exclusion site was quantified from hyperenhancement area on preoperative delayed-enhancement magnetic resonance imaging as percentage of fibrosis (total infarct size relative to ventricular mass). RESULTS Calculated percentage of fibrosis varied from 0% to 29.9% (mean 12% +/- 9.6%). Percentage of fibrosis linearly correlated with significantly worse postoperative hemodynamic variables and left ventricular function recovery: left ventricular ejection fraction (P = .0005, R = -0.79), left ventricular end-systolic volume index (P = .05, R = 0.51), mean pulmonary arterial pressure (P = .004, R = 0.70), pulmonary capillary wedge pressure (P = .009, R = 0.65), and cardiac index (P = .005, R = -0.69). At mean 30-month follow-up, 4 patients with recurrent heart failure had significantly greater percentage of fibrosis than did those without recurrence (19% +/- 8.2% vs 8.8% +/- 8.6%, P = .04). CONCLUSION Amount of myocardial scarring at left ventricular base affected postoperative left ventricular function and hemodynamic improvements. Preoperative quantitative assessment of remote myocardial status with delayed-enhancement magnetic resonance imaging may predict outcomes for patients undergoing surgical ventricular restoration.

Clinical management of lower limb ischemia secondary to a persistent sciatic artery aneurysm: Report of a case

A persistent sciatic artery (PSA) is a rare congenital malformation, frequently complicated by atherosclerotic changes such as aneurysmal formation. Optimal treatment is dependent on the individual situation. We report a case of a PSA aneurysm complicated by lower limb ischemia. Graft interposition with distal balloon angioplasty and thrombectomy from the posterior transgluteal approach was performed successfully, without any complications.

Quadricuspid aortic valve complicated with infective endocarditis: report of a case

Congenital quadricuspid aortic valve is a rare cardiac malformation with an unknown risk of infective endocarditis. We report a case of quadricuspid aortic valve complicated with infective endocarditis. A 53-year-old Japanese woman was hospitalized with leg edema and a fever of unknown origin. Corynebacterium striatum was detected in the blood culture. Echocardiography demonstrated a quadricuspid aortic valve with vegetation and severe functional regurgitation. The condition was diagnosed as a quadricuspid aortic valve with infective endocarditis, for which surgery was performed. The quadricuspid aortic valve had three equal-sized cusps and one smaller cusp (type B according to Hurwitz classification). We dissected the vegetation and infectious focus and implanted a mechanical valve. Following the case report, we review the literature.

Surgical Treatment of Complications Associated with the Angio-Seal Vascular Closure Device: Report of Three Cases

The Angio-Seal arterial closure device consists of several bioabsorbable components and is used for hemostasis of arterial puncture sites. We report 3 cases of hemorrhagic and ischemic complications related to Angio-Seal use. Two cases were treated successfully by surgical removal of the device. In the third case surgical removal of the device failed and additional intervention was necessary. The unique structure of the Angio-Seal and the most likely cause of failure should be considered when treating device-related complications.

Surgical approach to left subclavian artery aneurysm in Marfan syndrome

We present a case of left subclavian artery aneurysm in a 48-year-old man with Marfan syndrome. Aneurysmectomy and interposition with an artificial graft were successfully performed through an infraclavicular incision by dividing the clavicle at its midshaft. The clavicle bone was reconstructed with a steel plate, and the postoperative course was uneventful. Because the arterial wall is fragile in cases of connective tissue disorders such as Marfan syndrome, our surgical approach was considered to be helpful for gentle maneuvering in an adequate operative field.

Left Ventricular Reconstructive Surgery in Ischemic Dilated Cardiomyopathy Complicated With Cardiogenic Shock

BACKGROUND The feasibility of left ventricular restoration for patients with ischemic cardiomyopathy complicated with cardiogenic shock remains unclear. We report early and mid-term outcomes of surgical interventions including left ventricular restoration for patients with cardiogenic shock. METHODS From April 2001 to June 2007, 10 patients with ischemic cardiomyopathy who developed cardiogenic shock underwent left ventricular restoration combined with mitral annuloplasty or coronary artery bypass grafting. All had been supported by a maximum dose of inotropic agents, 8 had required an intraaortic balloon pump, and 1 had required extracorporeal life support. Mean left ventricular end-diastolic and end-systolic volume indices were 142 +/- 33 mL/m(2) and 113 +/- 28 mL/m(2), respectively, and ejection fraction was 0.21 +/- 0.059. RESULTS There was no mortality at 30 days. Five patients demonstrated significant recovery after the operation. Three patients simultaneously underwent left ventricular assist system (LVAS) implantation with left ventricular restoration because of preexisting severe end-organ failure, and 2 of them were subsequently weaned from LVAS, although 1 required reimplantation. The other 2 patients eventually underwent LVAS implantation in the early postoperative period. Two patients who required prolonged LVAS support underwent successful heart transplantation. Seven patients are alive at a mean follow-up of 1.9 years. Patients who required prolonged LVAS support had significantly longer duration of heart failure symptoms (p = 0.04) and higher mean pulmonary artery pressure (p = 0.02) preoperatively. CONCLUSIONS Early combined surgical interventions including left ventricular restoration can be a choice of treatment even in patients with ischemic cardiomyopathy complicated with cardiogenic shock. Additional use of the LVAS followed by bridge to recovery or transplantation should be appropriately applied in these critically ill patients.

Diabetes mellitus adversely affects mortality and recurrence after valve surgery for infective endocarditis

Background: Although diabetes mellitus (DM) increases the incidence of infective endocarditis (IE), little is known about the outcome of valve surgery for active IE in patients with DM. We evaluated the clinical outcomes of valve surgery for IE in patients with DM. Methods: Between 2009 and 2016, 470 patients underwent valve surgery for definitive left‐sided active IE at 12 affiliated hospitals. We compared the preoperative variables and clinical outcomes between patients without (n = 374) and with DM (n = 96). Results: Staphylococcus and chronic hemodialysis were more prevalent in patients with DM, and these patients had greater preoperative inflammation levels and worse renal function than patients without DM. In‐hospital mortality was 8% in patients without DM and 13% in patients with DM (P = .187). The overall survival rate at 1 and 5 years was 87% and 81% in patients without DM and 72% and 59% in patients with DM (P < .001). The incidence of infection‐related death was greater in patients with DM than in patients without DM (P < .001; hazard ratio 3.74 [1.78‐7.71]). Freedom from the recurrence of endocarditis at 1 and 5 years postoperatively was 98% and 95% in patients without DM, and 89% and 78% in patients with DM (P < .001), respectively. The Cox hazard analysis revealed that the presence of DM was the only independent risk for recurrence (hazard ratio 3.74 [1.45‐9.54], P = .007). Conclusions: The short‐ and mid‐term outcome after valve surgery for active IE in patients with DM is worse because of the greater prevalence of infection‐related death and IE recurrence.

Mid-term results of small-sized St. Jude Medical Regent prosthetic valves (21 mm or less) for small aortic annulus

Prosthesis–patient mismatch (PPM) is always of concern when performing aortic valve replacement (AVR) in patients with a small aortic annulus. Although bioprosthetic AVR is preferred in patients older than 65 years, we have experienced cases in elderly patients with a small aortic annulus whereby we could not implant small-sized bioprosthetic valves. We have implanted St. Jude Medical Regent (SJMR) mechanical valves (St. Jude Medical, St. Paul, MN, USA) as necessary, even in elderly patients with no aortic annulus enlargement. We investigated our experiences of AVR with SJMR mechanical valves of 21 mm or less in size. Between January 2006 and December 2009, 40 patients underwent AVR with SJMR mechanical valves ≤21 mm in size: 9 patients received 21-mm valves, 19 received 19-mm valves, and 12 received 17-mm valves. The mean age was 65.9 ± 9.5 years, and 25 patients (62.5 %) were 65 years or older. We evaluated the clinical outcome and the echocardiographic data for each valve size. There was no operative or hospital mortality. The mean duration of clinical follow-up was 31.2 ± 17.6 months. During follow-up, there were no hospitalizations due to heart failure. The cumulative valve-related event-free survival was 93 % at 33 months, and the cumulative hemorrhagic event-free survival was 93 % at 33 months and 84 % at 43 months, using the Kaplan–Meier method. At follow-up, the mean values of the measured effective orifice area (EOA) for the 21-, 19-, and 17-mm prostheses were 2.00 ± 0.22, 1.74 ± 0.37, and 1.25 ± 0.26 cm2, and the mean measured EOA index (EOAI) were 1.17 ± 0.12, 1.11 ± 0.21 and 0.90 ± 0.22 cm2/m2, respectively. A PPM (EOAI ≤0.85) was documented in 5 patients, all of whom had received a 17-mm SJMR valve. AVR with SJMR valves of 21 mm or less in size appears to show satisfactory clinical and hemodynamic results.