ABSTRACT: Hepatopulmonary syndrome (HPS) is of prognostic value in patients awaiting for orthotopic liver transplantation (OLT), but little is known about the effect of cirrhotic cardiomyopathy (CCM). The aim of the present study was to estimate the prevalence and possible relation between respiratory and cardiac abnormalities in a same series of patients awaiting OLT. Special attention was paid to the prognostic value of CCM in comparison to HPS. Eighty-three patients were included (19 females, 64 males; 52.1 ± 10.0 yrs). All had lung function testing with arterial blood gases and echocardiographic evaluation at rest with a contrast echocardiography in case of arterial oxygenation defect. To estimate the presence of CCM, patients underwent a complete left and right echocardiography and Doppler examination. Complete echocardiographic assessment could be obtained in 64 of the 83 patients of the study. HPS was observed in 16.9% (14/83) and CCM in 23.4% (15/64) of patients. There was a tendency of more serious adverse events before and after OLT in patients with HPS in comparison to others but CCM was not of prognostic value. HPS and CCM were frequent in these patients awaiting OLT but both abnormalities were not found in the same patients. CCM was neither related to death before OLT nor to death or serious adverse events after OLT.
Respiratory medicine 04/2013; · 2.33 Impact Factor
ABSTRACT: Endothelial dysfunction is associated with the decreased exercise capacity observed in heart-transplant (HTx) recipients. L-arginine supplementation (LAS) stimulates the nitric oxide (NO) pathway and restores endothelial function.
We compared exercise capacity in healthy subjects and HTx patients and investigated whether chronic LAS might improve exercise capacity and NO/endothelin balance after an HTx.
Clinical, echocardiographic, and exercise characteristics were measured in 11 control subjects and 22 HTx recipients. In a prospective, double-blind study, the 22 HTx recipients performed a 6-min exercise [6-min-walk test (6MWT)] and a maximal bicycle exercise test before and after a 6-wk period of placebo intake or LAS. Endothelial function was measured by analyzing blood NO metabolites, endothelin, and the resulting NO/endothelin balance.
Exercise capacity decreased after transplantation. Unlike with the placebo intake, 6 wk of LAS improved quality of life in HTx recipients (mean +/- SEM Minnesota Score: from 15.3 +/- 1.3 to 10.6 +/- 1.1; P < 0.001) and their submaximal exercise capacity. The distance walked during the 6MWT increased (from 525 +/- 20 to 580 +/- 20 m; P = 0.002), and the ventilatory threshold during the incremental test was delayed by 1.2 min (P = 0.01). Central factors such as resting stroke volume, systolic pulmonary arterial pressure, cardiac systolodiastolic functions, and heart-rate reserve were not modified, but LAS significantly increased the NO:endothelin ratio (from 2.49 +/- 0.38 to 3.31 +/- 0.39; P = 0.03).
Oral LAS may be a useful adjuvant therapeutic to improve quality of life and exercise tolerance in HTx recipients.
American Journal of Clinical Nutrition 03/2010; 91(5):1261-7. · 6.67 Impact Factor
ABSTRACT: Endothelial dysfunction is a significant cause of vascular and end-organ damage after solid organ transplantation. The aim of this study was to compare endothelial function in healthy controls and in patients who received tacrolimus for immunosuppression after orthotopic liver transplantation (OLT).
Eight OLT patients and eight age- and BMI-matched healthy subjects were included in the study. Apart from hemodynamic parameters, enzymatic liver function, fasting plasma glucose levels, creatinine, cholesterol, nitric oxide and endothelin-1 levels were measured. Flow-mediated dilatation (FMD) in the brachial artery was determined by bi-mode ultrasound.
Systolic and diastolic blood pressure and heart rate were higher in OLT recipients compared with the control group, but remained within normal limits. Blood results did not differ significantly between the groups. Circulating nitric oxide (152.2 +/- 29.7 vs. 180.6 +/- 40.1 micromol/L) and endothelin-1 (20.5 +/- 1.0 vs. 18.9 +/- 1.3 pmol/L) values were similar, and the FMD was normal in both groups (10.29 +/- 0.89 vs. 9.86 +/- 2.43% in controls and OLT recipients, respectively). There was a significant positive correlation between plasma tacrolimus levels after OLT and FMD (r = 0.72, p < 0.05).
As assessed by both laboratory and functional approaches, endothelial function was unaltered in patients taking tacrolimus after OLT. The positive correlation between tacrolimus plasma levels and FMD suggest that tacrolimus might have beneficial effects on endothelial function after OLT.
Clinical Transplantation 07/2009; 23(6):897-903. · 1.67 Impact Factor
ABSTRACT: To determine whether the six-minute walk test (6MWT) might predict peak oxygen consumption (VO2peak) after heart transplantation.
Case-control prospective study.
Patients with heart transplant (n=22) and age-matched sedentary male subjects (n=13).
Exercise performance using a maximal exercise test, distance walked using the 6MWT, heart rate, and VO2peak.
Compared with controls, exercise performance was decreased in patients with heart transplant with less distance ambulated (516+/-13m vs 592+/-13m; P<.001) and a decrease in mean VO2peak (23.3+/-1.3 vs 29.6+/-1mL x min(-1) x kg(-1); P<.001). Patients with heart transplant showed an increased resting heart rate, a response delayed both at the onset of exercise and during recovery. However, the patient's heart rate at the end of the 6MWT was similar to that obtained at the ventilatory threshold. The formula did not predict measured VO2, with a weak correlation observed between the six-minute walk distance and both VO2peak (r=.53; P<.01) and ventilatory threshold (r=.53; P<.01) after heart transplantation. Interestingly, when body weight was considered, correlations coefficient increased to .74 and .77, respectively (P<.001).
In heart transplant recipients, the 6MWT is a safe, practical, and submaximal functional test. The distance-weight product can be used as an alternative method for assessing the functional capacity after heart transplantation but cannot totally replace maximal VO2 determination.
Archives of physical medicine and rehabilitation 02/2009; 90(1):51-7. · 2.18 Impact Factor
ABSTRACT: Recent data demonstrated that hind limb ischemia induces skeletal muscle mitochondrial dysfunctions. Improvement of such metabolic myopathy improves patient's symptomatology, supporting the development of experimental models focused on mitochondrial function analysis. However, although the nonischemic contralateral leg is often used as a control during unilateral leg ischemia, whether it might be useful when assessing ischemia-induced mitochondrial dysfunction remains to be investigated.
Both ischemic (IR) and nonischemic contralateral legs (CTL) of rats (n=13) submitted to 5 h ischemia induced by a rubber band tourniquet applied on the root of the hind limb were studied and compared to that of sham-operated animals (SHAM, n=13). Maximal oxidative capacities (V(max)) and complexes I, II and IV activities of the gastrocnemius mitochondrial respiratory chain were determined, using glutamate-malate, succinate (Vs) and TMPD-ascorbate (V(TMPD)) substrates.
V(max) was decreased in IR (4.6+/-0.4 microM/min/g dry weight) compared to both SHAM and CTL muscles (8.5+/-0.5 and 7.1+/-0.4 microM/min/g dry weight, -46% and -36%, P<0.001, respectively). V(S) and V(TMPD) were reduced in IR muscle (-56% and -48% for V(S); and -25% and -24% for V(TMPD), P<0.001) as compared to SHAM and CTL). V(S) and V(TMPD) were similar in SHAM and CTL muscles.
Five hours ischemia-reperfusion significantly impaired complexes I, II and IV of the ischemic skeletal muscle mitochondrial respiratory chain. Interestingly, only V(max) was slightly altered in the contralateral leg, supporting that the nonischemic leg might be used as a control when assessing mitochondrial function in the experimental setting of unilateral hind limb ischemia.
Journal of Surgical Research 09/2008; 155(1):65-9. · 2.25 Impact Factor
The Journal of heart and lung transplantation: the official publication of the International Society for Heart Transplantation 04/2007; 26(3):302-3. · 3.54 Impact Factor