Shuichi Kitada

Usefulness of Fibrinogen/Fibrin Degradation Product to Predict Poor One-Year Outcome of Medically Treated Patients With Acute Type B Aortic Dissection

Previous studies have indicated that medical therapy provides excellent outcomes for patients with uncomplicated Stanford type B acute aortic dissection. However, affected aortas are often compromised by aneurysmal dilatation and rupture, resulting in poor outcomes. The purpose of this study was to determine predictors of aortic events in patients with Stanford type B acute aortic dissection receiving conservative medical therapy. The study group consisted of 78 consecutive patients with Stanford type B acute aortic dissection who were admitted to the hospital within 48 hours of onset. These patients were treated medically and followed up for 1 year. Aortic events were defined as rupture, recurrent dissection, aortic expansion with diameter>or=60 mm, rapid aortic expansion at a rate of >or=10 mm/yr, and the development of visceral or limb ischemia. Predictors of these events were determined using multivariate analyses. During 1-year follow-up, aortic events were observed in 13 (17%) patients, including aortic rupture in 3 (4%), aortic diameter>or=60 mm in 4 (5%), rapid expansion of the aorta in 3 (4%), and the development of visceral or limb ischemia in 3 (4%). On multivariate analysis, fibrinogen-fibrin degradation product level>or=20 microg/ml (odds ratio 7.802, 95% confidence interval 1.405 to 43.335) on admission was the only independent predictor of aortic events at 1 year. In conclusion, careful monitoring is required for patients with medically treated Stanford type B acute aortic dissection associated with fibrinogen-fibrin degradation product level>or=20 microg/ml on admission.

Pre-operative echocardiographic features associated with persistent mitral regurgitation after left ventricular assist device implantation

BACKGROUND Previous studies have shown remarkable decrease in size of the left ventricle after left ventricular assist device (LVAD) implantation due to mechanical unloading. However, a certain number of patients continue to have significant mitral regurgitation (MR) under LVAD support. We investigated pre-operative echocardiographic features associated with persistent MR after LVAD implantation. METHODS We retrospectively reviewed 82 consecutive patients undergoing continuous-flow LVAD implantation between 2007 and 2010. We obtained echocardiograms performed within 2 weeks before and 1 week after surgery. We investigated the pre-operative echocardiographic findings associated with significant MR post-LVAD and compared 1-year mortality after LVAD surgery between patients with and without significant MR post-LVAD. RESULTS MR was significant in 43 patients (52.4%) before LVAD surgery. Among those, 5 underwent concomitant mitral valve repair (MVr) at the time of LVAD implantation. Of the remaining 38 patients, 25 (65.8%) showed improvement of MR, whereas 13 patients (34.2%) continued to have significant MR post-LVAD. Multivariate analysis revealed that posterior displacement of the coaptation point of mitral leaflets was significantly associated with significant MR post-LVAD (hazard ratio, 1.335; 95% confidence interval, 1.035-1.721; p = 0.026) even after adjusting for the amount of pre-operative MR flow. Post-LVAD 1-year survival of patients with and without significant MR post-LVAD was not significantly different (92.3% vs 89.1%, p = 0.826). CONCLUSIONS Pre-LVAD posterior displacement of mitral leaflets may be indicative of post-operative significant MR, which would help identify echocardiographic features of functional MR refractory to simple volume reduction of the ventricle.

Value of Serial Echo‐Guided Ramp Studies in a Patient with Suspicion of Device Thrombosis after Left Ventricular Assist Device Implantation

Thrombus formation inside of the pump is a major cause for device malfunction following the left ventricular assist device (LVAD) implantation. We recently established a novel ramp test protocol facilitating continuous bedside echo monitoring to optimize LVAD function and diagnosing device malfunctions. We describe a case of 29‐year‐old woman undergoing HeartMate II LVAD implantation, in whom serial ramp studies were used to diagnose intra‐device thrombus after device implantation. The 1st ramp study at postoperative day (POD) 26 revealed adequate reduction in ventricular size according to the increase in LVAD speed (left ventricular end‐diastolic diameter [LVEDD] at minimum and maximum speeds, 68 and 37 mm, respectively). The patient was discharged home and received routine anticoagulation maintenance therapy. However, a 2nd ramp test was performed on POD 56 due to increased lactase dehydrogenase and brain natriuretic peptide levels and showed marked increase in left ventricle (LV) chamber size without adequate response to the LVAD speed changes (LVEDD at minimum and maximum speeds, 88 and 76 mm, respectively). Given the suspicion for partial pump thrombosis, the patient was immediately hospitalized and received intravenous heparin infusion. After the optimization of the intensive anticoagulation therapy, the patient underwent a 3rd ramp study, which showed a remarkable improvement of the adequate response to LVAD speed changes. The patients eventually underwent cardiac transplant successfully, and the partial clot was found inside of the pump. This case demonstrates the usefulness of serial ramp studies in patients who are suspected to have device thrombosis.

LEFT VENTRICULAR LONGITUDINAL STRAIN BY SPECKLE-TRACKING ECHOCARDIOGRAPHY FOR THE DETECTION OF TREATMENT-REQUIRING REJECTION IN CLINICALLY ASYMPTOMATIC HEART TRANSPLANT RECIPIENTS

Non-invasive detection of rejection is a major objective in the management of heart transplant recipients. We investigated the utility of 2-dimensional speckle-tracking echocardiography (2D-STE) for detecting allograft rejection. We retrospectively evaluated 170 endomyocardial biopsy specimens from