Leucocyte- and platelet-rich fibrin (L-PRF) as a regenerative medicine strategy for the treatment of refractory leg ulcers: a prospective cohort study.

Chronic wounds (VLU: venous leg ulcer, DFU: diabetic foot ulcer, PU: pressure ulcer, or complex wounds) affect a significant proportion of the population. Despite appropriate standard wound care, such ulcers unfortunately may remain open for months or even years. The use of leukocyte- and platelet-rich fibrin (L-PRF) to cure skin ulcers is a simple and inexpensive method, widely used in some countries but unknown or neglected in most others. This auto-controlled prospective cohort study explored and quantified accurately for the first time the adjunctive benefits of topical applications of L-PRF in the management of such refractory ulcers in a diverse group of patients. Forty-four consecutive patients with VLUs (n = 28, 32 wounds: 17 ≤ 10 cm2 and 15 > 10 cm2), DPUs (n = 9, 10 wounds), PUs (n = 5), or complex wounds (n = 2), all refractory to standard treatment for ≥3 months, received a weekly application of L-PRF membranes. L-PRF was prepared following the original L-PRF method developed more than 15 years ago (400g, 12 minutes) using the Intra-Spin L-PRF centrifuge/system and the XPression box kit (Intra-Lock, Boca Raton, FL, USA; the only CE/FDA cleared system for the preparation of L-PRF). Changes in wound area were recorded longitudinally via digital planimetry. Adverse events and pain levels were also registered. All wounds showed significant improvements after the L-PRF therapy. All VLUs ≤ 10 cm2, all DFUs, as well as the two complex wounds showed full closure within a 3-month period. All wounds of patients with VLUs > 10 cm2 who continued therapy (10 wounds) could be closed, whereas in the five patients who discontinued therapy improvement of wound size was observed. Two out of the five PUs were closed, with improvement in the remaining three patients who again interrupted therapy (surface evolution from 7.35 ± 4.31 cm2 to 5.78 ± 3.81 cm2). No adverse events were observed. A topical application of L-PRF on chronic ulcers, recalcitrant to standard wound care, promotes healing and wound closure in all patients following the treatment. This new therapy is simple, safe and inexpensive, and should be considered a relevant therapeutic option for all refractory skin ulcers.

In vivo assessment of a new method of pulsatile perfusion based on a centrifugal pump.

The aim of this study was to assess platelet dysfunction and damage to organs after extracorporeal circulation using a pump based on a new method that adds a pulsatile flow to the continuous flow provided by a centrifugal pump. The continuous component of the total flow (2-3 L/min) is created by a Bio-Pump centrifugal pump, while the pulsatile component is created by the pulsating of an inner membrane pneumatically controlled by an intra-aortic counterpulsation balloon console (systolic volume of 37.5 mL in an asynchronous way with a frequency of 60 bpm). Six pigs were subjected to a partial cardiopulmonary bypass lasting 180 min and were sacrificed 60 min after extracorporeal circulation was suspended. The hematological study included the measurement of hematocrit, hemoglobin, leukocytes, and platelet function. The new pump did not significantly alter either platelet count or platelet function. In contrast, hematocrit and hemoglobin were significantly reduced during extracorporeal circulation (approximately 5% P = 0.011, and 2 g/dL P = 0.01, respectively). The leukocyte count during extracorporeal circulation showed a tendency to decrease, but this was not significant. In general, the short-term use of the new pump (4 h) did not cause any serious morphological damage to the heart, lung, kidney, or liver. The results suggest that the hemodynamic performance of the new pump is similar to a conventional centrifugal pump and could therefore be appropriate for use in extracorporeal circulation.

Dual-source CT for visualization of the coronary arteries in heart transplant patients with high heart rates.

OBJECTIVE: The purpose of this study was to evaluate the quality of dual-source CT images of the coronary arteries in heart transplant recipients with high heart rates. SUBJECTS AND METHODS: Contrast-enhanced dual-source CT coronary angiography was performed on 23 heart transplant recipients (20 men, three women; mean age, 61.1 +/- 12.8 years). Data sets were reconstructed in 5% steps from 30% to 80% of the R-R interval. Two blinded independent readers using a 5-point scale (0, not evaluative; 4, excellent quality) assessed the quality of images of coronary segments. RESULTS: The mean heart rate during scanning was 89.2 +/- 10.4 beats/min. Interobserver agreement on the quality of images of the whole coronary tree was a kappa value of 0.78 and for selection of the optimal reconstruction interval was a kappa value of 0.82. The optimal reconstruction interval was systole in 17 (74%) of the 23 of heart transplant recipients. At the best reconstruction interval, diagnostic image quality (score >or= 2) was obtained in 92.1% (303 of 329) of the coronary artery segments. The mean image quality score for the whole coronary tree was 3.1 +/- 1.01. No significant correlation between mean heart rate (rho = 0.31) or heart rate variability (rho = 0.23) and overall image quality score was observed (p = not significant). CONCLUSION: Dual-source CT acquisition yields coronary angiograms of diagnostic quality in heart transplant recipients. Mean heart rate and heart rate variability during scanning do not have a negative effect on the overall quality of images of the coronary arteries.

Dual-source CT in heart transplant recipients: quantification of global left ventricular function and mass.

OBJECTIVE: To evaluate reliability of global left ventricular (LV) function and mass quantification in heart transplant recipients undergoing cardiac dual-source computed tomography examinations by means of manual contour tracing and using a region-growing-based semiautomatic segmentation analysis software tool. MATERIALS AND METHODS: Twenty-six consecutive heart transplant recipients undergoing cardiac dual-source computed tomography examinations with tube current modulation were included. Double-oblique short-axis 8-mm slice thickness multiphase image reconstructions were used for manual contouring and axial 0.75 mm slices were used for the semiautomated segmentation. LV ejection fraction, end-diastolic volume, end-systolic volume, stroke volume, cardiac output, and myocardial mass were assessed by both segmentation methods. Length of time needed for manual contour tracing and for the semiautomated software was recorded. Contrast-to-noise ratio was calculated in end-diastolic and end-systolic images. RESULTS: No statistically significant differences were observed in LV functional parameters derived from semiautomatic contour detection algorithm as compared with manual contouring, with excellent agreement (concordance-correlation coefficient >or=0.80). The semiautomated contour detection algorithm overestimated LV mass (mean difference 12.84+/-3.39) (P<0.001). The evaluated software allowed to quantify LV parameters in a significantly shorter period of time (mean difference 201.68+/-121.98 s, P<0.001). Contrast-to-noise ratio in end-systole and end-diastole statistically differed (mean difference 5.29+/-2.94 Hounsfield units; P<0.01) but did not significantly hamper the semiautomated segmentation. CONCLUSIONS: Objective quantification of LV volumes using the evaluated semiautomated segmentation software is precise, reproducible, and time effective.

Dual-source CT coronary angiogram in heart transplant recipients in comparison with dobutamine stress echocardiography for detection of cardiac allograft vasculopathy.

Conventional coronary angiography (CCA) is the gold standard in the diagnosis of cardiac allograft vasculopathy (CAV) in heart transplant recipients. Dobutamine stress echocardiography (DSE) is a useful technique for screening. Dual-source computed tomography (DSCT) is the last generation of computed tomography scanners, which could be useful to noninvasively assess CAV. Thirty cardiac transplant recipients underwent DSE and DSCT coronary angiogram. Exclusion criteria were as follows: renal insufficiency, iodinated contrast media allergy, less than 12 months since transplant, and unstable clinical conditions. DSE showed ischemia in two patients. At DSCT scan 13 patients had a normal angiogram, 13 ones wall thickening and four significant diseases. DSCT showed a sensitivity of 100% with a specificity of 92%. DSCT allowed detection of more patients with CAV than DSE. Four patients showed significant CAV at DSCT compared with two at DSE. Thirteen patients showed initial signs of disease at DSCT despite a normal DSE.

Quantification of left ventricular function and mass in heart transplant recipients using dual-source CT and MRI: initial clinical experience.

The purpose of this study was to compare LV function and mass quantification derived from cardiac dual-source CT (DSCT) exams with those obtained by MRI in heart transplant recipients. Twelve heart transplant recipients who underwent cardiac DSCT and MRI examination were included. Double-oblique short-axis 8-mm slice thickness images were evaluated. Left ventricular ejection fraction, end-diastolic volume, end-systolic volume, stroke volume, cardiac output and myocardial mass were manually assessed for each patient by two blinded readers. A systematic overestimation of all left ventricular volumes by DSCT when compared with MRI was observed. Mean difference was 16.58 +/- 18.61 ml for EDV, 4.9 4 +/- 6.84 ml for ESV, 11.64 +/- 13.58 ml for SV and 5.73 +/- 1.14 l/min for CO. Slightly lower values for left ventricular ejection fraction with DSCT compared with MRI were observed (mean difference 0.34 +/- 3.18%, p = 0.754). Correlation between DSCT and MRI for left ventricular mass was excellent (rho = 0.972). Bland and Altman plots and CCC indicated good agreement between DSCT and MRI left ventricular function and mass measurements. The interobserver correlation was good. In conclusion, DSCT accurately estimates left ventricular ejection fraction, volumes and mass in heart transplant recipients.

Dual-source CT coronary imaging in heart transplant recipients: image quality and optimal reconstruction interval.

The image quality and optimal reconstruction interval for coronary arteries in heart transplant recipients undergoing non-invasive dual-source computed tomography (DSCT) coronary angiography was evaluated. Twenty consecutive heart transplant recipients who underwent DSCT coronary angiography were included (19 male, one female; mean age 63.1 +/- 10.7 years). Data sets were reconstructed in 5% steps from 30% to 80% of the R-R interval. Two blinded independent observers assessed the image quality of each coronary segments using a five-point scale (from 0 = not evaluative to 4 = excellent quality). A total of 289 coronary segments in 20 heart transplant recipients were evaluated. Mean heart rate during the scan was 89.1 +/- 10.4 bpm. At the best reconstruction interval, diagnostic image quality (score > or = 2) was obtained in 93.4% of the coronary segments (270/289) with a mean image quality score of 3.04 +/- 0.63. Systolic reconstruction intervals provided better image quality scores than diastolic reconstruction intervals (overall mean quality scores obtained with the systolic and diastolic reconstructions 3.03 +/- 1.06 and 2.73 +/- 1.11, respectively; P < 0.001). Different systolic reconstruction intervals (35%, 40%, 45% of RR interval) did not yield to significant differences in image quality scores for the coronary segments (P = 0.74). Reconstructions obtained at the systolic phase of the cardiac cycle allowed excellent diagnostic image quality coronary angiograms in heart transplant recipients undergoing DSCT coronary angiography.

Prevalence of metabolic syndrome in heart transplant patients: role of previous cardiopathy and years since the procedure--the TRACA study.

BACKGROUND: Metabolic syndrome (MS) is a cluster of cardiovascular risk factors highly prevalent in patients with ischemic heart disease (IHD), the main etiologic cause for heart transplantation (HT). METHODS: Data for 111 HT patients of a single institution were collected. The assessment of MS was made, according to the ATP III criteria, when 3 of the following diagnostic criteria were present: waist circumference >102 cm (men) or >88 cm (women); triglycerides > or =150 mg/dl; HDL-cholesterol <40 mg/dl (men) or <50 mg/dl (women); blood pressure > or =130/85 mm Hg; and fasting glucose > or =110 mg/dl, or diabetes mellitus previously diagnosed. Renal function was assessed by glomerular filtration rate, as estimated by the MDRD abbreviated equation. RESULTS: Mean age of the 111 HT patients was 63.0 (11.0) years and 101 (91.0%) were men. The median time since transplant was 7.0 (3.0 to 13.0) years, and IHD was the primary cause for HT (56.8%). The prevalence of MS was 42.3% and was statistically higher in patients with IHD prior to HT (52.4% vs 27.2%; p = 0.007). Patients with MS were older but had the same time of follow-up since their HT. An analysis of the sample in tertiles of years since HT showed that MS was more prevalent in subjects who received HT due to IHD only in the lowest and highest tertile. Fifty-three patients (47.7%) had abdominal obesity, 47 (43.2%) were overweight and 22 (19.8%) were obese; most patients with abdominal obesity were diagnosed with MS (82.6%). Multivariate analysis showed a strong association between abdominal obesity and MS (odds ratio [OR] 6.2, 95% confidence interval [CI] 1.9 to 19.8), even after adjustment for body mass index, and also showed an independent association of MS with severe renal dysfunction (OR 9.8; p = 0.02). CONCLUSIONS: MS is highly prevalent in HT patients and abdominal obesity is the leading cause of this clustering. IHD status and time since HT are major determinants in the prevalence of MS in HT patients.