Peter H.U. Lee

Heart transplantation with or without prior mechanical circulatory support in adults with congenital heart disease

OBJECTIVES Recent analyses establish that heart transplantation is increasing among adults with congenital heart disease (ACHD), but the effects of pretransplant mechanical circulatory support (MCS) on perioperative and post-transplant outcomes have not been examined in the ACHD population. METHODS Scientific Registry of Transplant Recipients data on all adult heart transplants from September 1987 to September 2012 (n = 47 160) were classified based on primary diagnosis codes as CHD or non-CHD and MCS or non-MCS. Demographic, procedural, outcome and survival variables were compared between MCS and non-MCS ACHD patient groups. RESULTS MCS was used in 83 (6.8%) ACHD patients compared with 8625 (18.8%) patients without CHD (P < 0.001). MCS as a fraction of ACHD transplants increased over time (P = 0.002). MCS patients spent more time on the wait list, had a higher baseline serum creatinine and were more likely to be male, status 1A, hospitalized, in the ICU and/or on a ventilator prior to transplant. However, MCS patients experienced equivalent short-term survival (30-day mortality = 10.8% in MCS vs 13.5% in non-MCS, P = 0.62) and overall survival by Kaplan-Meier analysis (P = 0.57). MCS patients had a longer post-transplant length of stay and were more likely to be transfused, but otherwise had no significant differences in adverse outcomes. CONCLUSIONS MCS is less commonly used in adult CHD patients compared with all patients undergoing heart transplant, but has been increasing over time. Within the ACHD population, patients with MCS have a higher risk profile, but except for increased transfusion rate and longer length of stay, do not experience less favourable post-transplant outcomes.

A Novel, Catheter-Based Approach to Left Ventricular Assist Device Deactivation After Myocardial Recovery

We describe a case of catheter-based embolization and deactivation of a left ventricular assist device using an Amplatzer plug for a patient demonstrating myocardial recovery after diagnosis of nonischemic cardiomyopathy. This procedure can provide a minimally invasive, low morbidity solution for patients wishing to be separated from left ventricular assist device support who want to avoid invasive surgery for device removal.

Effects of weightlessness and movement restriction on the structure and metabolism of the soleus muscle in monkeys after space flight.

After humans and animals have been in conditions of real and modeled weightlessness, the most marked changes are seen in the “slow” tonic muscles, particularly soleus. Studies of the effects of weightlessness and movement restriction on the soleus muscle in monkeys demonstrated significant reductions in the sizes of slow and rapid fibers due mainly to the actions of real weightlessness (rather than movement restriction in the space capsule). Protein loss in soleus muscle fibers in monkeys following space flight was more marked than loss of other components, including water. The level of atrophy of soleus muscle fibers in these conditions was greater than the decrease in the number of capillaries. Succinate dehydrogenase activity in soleus muscle fibers decreased proportionally to the reduction in fiber size.

Fungal Pulmonary Valve Endocarditis Masquerading as a Pulmonary Embolism

Septic pulmonary emboli (SPE) can be a difficult clinical entity to distinguish from thromboembolic pulmonary embolism (TPE) in a patient with history of IV drug abuse (IVDA). We present a case of a patient who presented with failure to thrive and presumed diagnosis of recurrent PE that ultimately was discovered to have fungal pulmonary valve endocarditis resulting in a right ventricular outflow obstruction. This required replacement of the pulmonary valve and repair of the right ventricular outflow tract. This case highlights difficulty in differentiating pulmonary valve endocarditis with septic emboli from chronic PE in a patient with a complex medical history.

Anticoagulation management following left ventricular assist device implantation is similar across all provider strategies

OBJECTIVES Thromboembolic and bleeding events are potential complications following left ventricular assist device implantation. A tight control of the international normalized ratio (INR) is believed to be crucial in the reduction of postimplant complications. There is significant variability among institutions as to whether a device implanting centre should be managing the INR. In this study, we evaluated the effect of INR management strategies in maintaining a therapeutic INR. METHODS A retrospective review was utilized to identify patients implanted with either the HeartMate II or the HeartWare HVAD between January 2011 and February 2016. Patients were stratified into 4 groups based on the post-discharge INR management strategy: outside hospital system anticoagulation clinic, outside hospital primary care provider, implanting centre anticoagulation clinic or implanting centre ventricular assist device office. The INR data were collected and analysed for both the early (discharge, 7, 14, 21 and 30 days) and late (3, 6, 9 and 12 months) postoperative periods. RESULTS There were 163 patients identified during the study period who met the study inclusion criteria: 49 (30%) patients were managed by an outside hospital system anticoagulation clinic, 59 (36.2%) patients by an outside hospital physician/primary care provider, 22 (13.5%) patients by the implanting centre anticoagulation clinic and 33 (20.2%) patients by the implanting centre ventricular assist device office. There were no statistically significant differences found between management strategies across all time points. CONCLUSIONS There was no statistically significant difference found between the management strategies examined. Regardless of the chosen INR management strategy, patients have similar INR values and postoperative outcomes.