Movement therapy in lung transplantation candidates assisted by a lightweight wearable robot.

The aim of this pilot-study was to investigate the safety, feasibility and tolerability of an assisted mobilization of patients with advanced pulmonary diseases, using a lightweight, exoskeleton-type robot (Myosuit, MyoSwiss AG, Zurich, Switzerland). Ten patients performed activities of daily life (ADL) both with and without the device. The mean age was 53.6 (±5.6) years; 70% were male. The assessment of outcome included the evaluation of vital signs, adverse events, rates of perceived exertion and dyspnea (PRE, PRD), the ability to perform ADL and the individual acceptability. Robotic-assisted mobilization was feasible in all patients. No adverse events occurred. RPE and RPD showed no significant difference with or without the Myosuit (mean difference in RPE -1.7, 95%-confidence interval (CI) -1.16, 4.49; p = 0.211; mean difference in RPD 0.00, 95%-CI -1.88, 1.88; p = 0.475). 80% of patients were interested to participate in a robotic-assisted training on a regular basis. A robotic exoskeleton-assisted mobilization is safe, feasible, well-tolerated and well-accepted. The results are highly encouraging to further pursue this highly innovative approach.

Validity of the 6-Minute Walk Test in Patients with End-Stage Lung Diseases Wearing an Oronasal Surgical Mask in Times of the COVID-19 Pandemic.

BACKGROUND AND OBJECTIVES: The 6-minute walk test (6MWT), as a clinical assessment tool for functional exercise capacity, is an integral component of lung allocation scores (LASs). In times of the coronavirus disease (COVID-19) pandemic, patients underwent 6MWTs wearing a surgical mask in ambulatory care. We investigated the impact of wearing a mask on 6-minute walk distances (6MWDs). METHOD: 6MWDs of 64 patients with end-stage lung diseases wearing an oronasal surgical mask were retrospectively compared to previously investigated 6MWDs of the same cohort, in a pre-COVID-19 pandemic era, without wearing a mask. Four patients were excluded due to a primary vascular disease, 29 patients due to clinically unstable pulmonary functions, and 1 patient due to a psychiatric disorder. RESULTS: The median age of the patients included was 55 (46-58) years; 15 (48%) were male. Ten (32.2%) were on the Eurotransplant lung transplant waiting list with a median LAS of 34.3 (31.9-36.2). Twenty (64.5%) patients had chronic obstructive pulmonary diseases, 7 (22.6%) had interstitial lung diseases, and 4 (12.9%) had other end-stage lung diseases. The mean 6MWD without versus with wearing a mask was 306.9 (101.9) versus 305.7 (103.8) m, with a mean difference of -1.19 m (95% confidence interval -13.4 to 11.03). The observed difference is statistically equivalent to zero (p < 0.001). No significant differences in 6MWDs were observed between the clinical groups. CONCLUSION: Wearing an oronasal surgical mask did not affect the 6MWDs of patients with advanced lung diseases. Therefore, a masked 6MWT appears to provide a reliable examination of functional exercise capacity in this cohort.

Assessment of right ventricular adaptability to loading conditions can improve the timing of listing to transplantation in patients with pulmonary arterial hypertension.

BACKGROUND: Right ventricle (RV) performance is load dependent, and right-sided heart failure (RHF) is the main cause of death in pulmonary arterial hypertension (PAH). Prediction of RV worsening for timely identification of patients needing transplantation (Tx) is paramount. Assessment of RV adaptability to load has proved useful in certain clinical circumstances. This study assessed its predictive value for RHF-free and Tx-free outcome with PAH. METHODS: Between 2006 and 2012, all potential Tx candidates with PAH, without RHF at the first evaluation, were selected for follow-up (except congenital heart diseases). At selection and at each follow-up, N-terminal prohormone brain natriuretic peptide (NT-proBNP) and the 6-minute walk distance were measured, and RV adaptability to load was assessed by echocardiography. Collected data were tested for the ability to predict RV stability and Tx-free survival. RESULTS: During a 12-month to 92-month follow-up, RHF developed in 23 of 79 evaluated patients, despite similar medication and no differences in initial RV size and ejection fraction compared with the patients who remained stable. However, unstable patients had an initially lower RV load-adaptation index and afterload-corrected peak global systolic longitudinal strain-rate values as well as higher RV dyssynchrony, tricuspid regurgitation, and NT-proBNP levels (p ≤ 0.01). At certain cutoff values, these variables appeared predictive for 1-year and 3-year freedom from RHF and 3-year Tx-free survival. An RV load-adaptation index reduction of ≥20% showed the highest predictive value (90.0%) for short-term (≤1 year) RV decompensation. CONCLUSIONS: Assessment of RV adaptability to load allows prediction of RV function and Tx-free survival with severe PAH during the next 1 to 3 years. This can improve the timing of listing for Tx.

Clinical, haemodynamic and echocardiographic features of early cardiac graft dysfunction.

BACKGROUND: The main cause of early death after heart transplantation (HTx) is so-called early primary or secondary graft failure (GF). The risk of profound GF has not declined in the past decade, as the consequence of the liberalisation of donor acceptance criteria because of the scarcity of donors. It is therefore important to try to diagnose graft failure and recognise the mechanisms of early graft dysfunction. AIM: To establish haemodynamic and echocardiographic criteria of early GF to define patients who should be considered for assist device support or re-transplantation. METHODS: Between January 2000 and March 2009, 116 HTx patients were studied. On the basis of echocardiography and continuous invasive monitoring, three groups were identified: (1) The true graft failure group (GF) consisted of 46 patients; (2) The latent right ventricular (RV) dysfunction group (RV-D) consisted of 25 patients with small left ventricular (LV) chamber (〈 39 mm) and RV ejection fraction (RVEF) 〈 50%; (3) The control group consisted of 45 consecutive HTx patients without any haemodynamic complications. RESULTS: Postoperatively, only the GF group required large doses of norepinephrine (〉 0.3 µmg/kg/min) and inhalative NO (40 ppm). Nevertheless, right and left filling pressures were significantly higher than in the controls (right 12 ± 3.6 vs. 9.0 ± 2 and left atrial pressure 13.0 ± 3.2 vs. 9.6 ± 2 mm Hg, both p 〈 0.001). Cardiac index was significantly smaller (2.9 ± 0.7 vs. 3.7 ± 0.9, p 〈 0.001) but neither pulmonary artery pressure (29.5 ± 6 vs. 29.7 ± 7 mm Hg) nor transpulmonary gradient (6 ± 5 vs. 5.1 ± 5 mm Hg) nor pulmonary vascular resistance (273 ± 97 vs. 287 ± 144 dyn × s × cm-5) differed significantly from those of the control group. In the GF group, LV end diastolic dimension (LVEDD) was significantly smaller and function poorer than in controls (39.8 ± 5 vs. 44.4 ± 5 mm, respectively, p = 0.001). RV function was also significantly worse (RVEF 42.2 ± 14% vs. 56.0 ± 9%), respectively, p = 0.001), whereas RV dimension did not differ significantly. Mechanical support after failure of the initial medical treatment was necessary in 37% of patients; 29 (63.0%) patients from the GF group died, the cause of death being sepsis with multi-organ failure. In the RV-D group, remodelling was quite similar but LVEF was excellent and maximal systolic velocity from the posterior wall was significantly higher than in GF. No death occurred. CONCLUSIONS: True early GF represents a grave haemodynamic situation with high mortality. Bedside echocardiography helps to distinguish between latent RV dysfunction and true GF.

Prediction of true circulatory decompensation in chronic heart failure for optimal timing of mechanical circulatory support: non-invasive arterial-ventricular coupling.

BACKGROUND: Prospective comparative studies to predict the risk of hemodynamic deterioration in patients referred for transplantation were performed on the basis of standard invasive and non-invasive data and new wave intensity (WI) parameters. METHODS AND RESULTS: Study Group 1 consisted of 151 consecutive outpatients (age 48.7 ± 12 years; 110 men) with end-stage dilative cardiomyopathy. Group 2, consisting of 11 consecutive patients (age 50 ± 11 years; 6 men) with sinus rhythm and "true" decompensation, was used to create "critical values" of WI. There were no demographic or somatic (weight and height) differences between the groups. The follow-up period of ambulatory patients was 31 ± 8 months. Non-invasive WI was studied in the common carotid artery. Complete invasive and non-invasive data were also recorded on the day of investigation. During follow-up 44 pts were lost; there were 15 cardiac deaths (10%), life-saving ventricular assist device implantation in 10 (6.6%) and transplantation in 19 (12.7%). For statistical purposes this group was named the "events" Group B (n = 44). A predisposing factor for events (death, "true" decompensation and "urgent" transplantation in ambulatory patients) was low first peak ("cut-off value" assessed in Group 2 < 4100 mmHg*s³) (OR 45.6, CI 14.5-143.3, p < 0.001). Less powerful predictors of the risk of deterioration were pulmonary capillary pressure (PCP), diastolic pulmonary artery pressure (PAP) and E/A mitral wave relation (p = 0.05). CONCLUSIONS: The new ventricular-arterial coupling parameter 1st peak of WI can potentially be used to distinguish patients at high risk for true deterioration and death. This parameter can be used to predict the need for assist device implantation.

Survival of patients with idiopathic pulmonary arterial hypertension after listing for transplantation: impact of iloprost and bosentan treatment.

BACKGROUND: Survival after idiopathic pulmonary arterial hypertension (IPAH) diagnosis is often shorter than the waiting time for grafts. Iloprost and bosentan improve outcome in advanced IPAH (New York Heart Association Functional Class III), but there is controversy about the limits of their efficacy in end-stage (Class IV) IPAH. METHODS: We investigated the impact of iloprost (prostacyclin analog) and bosentan (endothelin-receptor antagonist) therapy on the outcome of patients with IPAH after listing for transplantation (Tx) to answer the following questions: (1) How efficient is this treatment in reducing mortality on waiting lists? (2) Is Tx still most promising for survival once recurrent right heart failure emerges, or can this treatment improve survival to an extent that exceeds post-Tx survival? We assessed the outcome of our IPAH patients listed for Tx between September 1996 and September 2005 in relation to kind and duration of medical treatment. RESULTS: Among 59 listed patients, 24 (40.7%) died before Tx, after 2.9 months (median). With iloprost and/or bosentan treatment the mortality on Tx lists was 33.3%, whereas with calcium-channel blockers it reached 64.3% (p < 0.05). Patients with iloprost and/or bosentan therapy showed similar survival, regardless of whether they responded to vasodilator testing. Survival after listing was better for patients who were transplanted than for those who received iloprost and/or bosentan but not Tx (p = 0.017). Iloprost and bosentan treatment allowed the withdrawal of 3 patients from Tx lists. CONCLUSIONS: Iloprost and bosentan allowed the effective bridge-to-transplant treatment in IPAH. However, with this treatment the mortality rate on Tx lists remained high and survival benefit was lower than from transplantation.

Risk stratification for renal transplantation after cardiac or lung transplantation: single-center experience and review of the literature.

BACKGROUND: Long-term survival after heart (HTx) or lung (LuTx) transplantation increases the risk for end-stage renal disease (ESRD). After HTx ESRD was reported to enhance mortality, and kidney transplantation (KTx) was shown to improve survival. However, prognostic factors in ESRD after HTx or LuTx are largely unknown. METHODS: Single-center observational study in HTx and LuTx patients who accessed the KTx waiting list; baseline characteristics were correlated with mortality. RESULTS: KTx was performed in 15 of 65 study patients. Survival was comparable on the KTx waiting list and in reference patients from the same center without ESRD. KTx significantly improved survival (5 years' survival 84.6% with KTx vs. 56.5% on the KTx waiting list, p = 0.030). None of the baseline parameters predicted mortality in the KTx group. Only on the KTx waiting list BMI (median 24.7 vs. 20.7; p < 0.05) and left ventricular ejection fraction (LVEF, median 63 vs. 53%, p < 0.008) significantly correlated with survival. CONCLUSIONS: The risk for mortality after HTx or LuTx is not increased by ESRD, provided that patients meet access criteria for the KTx waiting list. KTx improves survival in ESRD after HTx or LuTx. BMI and LVEF may predict outcome in HTx/LuTx patients on the KTx waiting list.