Aortic dilatation: Value of echocardiography in the systematic assessment of elite rugby players in the French National Rugby League (LNR).

The value of echocardiography in the screening of athletes in addition to the electrocardiogram is debated and still unclear. 336 rugby players in French professional divisions (Top 14, Pro D2) were prospectively assessed with electrocardiogram and echocardiography. 75% were Caucasian, 16.4% Pacific Islanders, and 8.6% Afro-Caribbean. Six (1.8%) players had electrocardiogram abnormalities, exclusively negative T waves. Twenty-one (6.25%) of them had abnormal echocardiography findings: one possible early hypertrophic cardiomyopathy, one anomalous origin of coronary artery, two left ventricular dilatations, one isolated bicuspid aortic valve, two aortic regurgitations, and 14 ascending aortic dilatations. The median aortic diameter was modestly correlated with age: 32 mm [23-48] in players aged ≤25 years vs 33.5 mm [24-50] in those aged >25 years (P = 0.02, correlation coefficient -.01). This tendency increased with cumulative hours of weight training: 34 mm [24-50] in forwards vs 32 mm [25-44] in backs (P = 0.01); and ethnicity, with Pacific Islanders having higher values in both raw data and body surface area or height-indexed data than Afro-Caribbeans and Caucasians: 34 [25-50] vs 32 [27-48] and 33 [23-49] mm (P = 0.017); 15 [12.2-21] vs 14.8 [11-19.9] and 14.8 [10-20.9] mm/m2 (P < 0.0001); 18.5 [14-25] mm/m vs 17.4 [14.8-25] mm/m and 17.6 [12.2-25.3] mm/m (P = 0.0125). In a population of professional rugby players, echocardiography was contributive. The main anomaly was aortic dilatation (14/336, 4.2%). While this is proportionally much higher than in other sports, the cutoffs need to be defined more precisely by including the criterion of ethnicity, as is already the case for electrocardiography.

Characterization of repolarization in Brugada syndrome patients during exercise testing: Dynamic angle evaluation.

BACKGROUND: A new ECG criterion has been studied in Brugada syndrome (BrS) at rest to differentiate type 2 and incomplete right bundle branch block (IRBBB). METHODS: We assessed this criterion during exercise comparing BrS (46 patients) and IRBBB (17 patients). A beta angle was measured from lead V1 between the upslope of S-wave and the downslope of the r'-wave. RESULTS: Beta angle was significantly larger in BrS at rest (58±24° vs 25±15°, p<0.001), exercise (47±26° vs 15±11°, p<0.001), and recovery (46±24° vs 21±12°, p<0.001) with a reduction in angle at exercise compared to rest. There was a significant rebound in angle at recovery in the control group to (p<0.001); no such rebound was observed in the BrS group (p=NS). CONCLUSION: Beta angle study at rest and its evolution at exercise could help discriminate BrS patients from healthy subjects.

Hypoxia-preconditioned mesenchymal stromal cells improve cardiac function in a swine model of chronic myocardial ischaemia.

OBJECTIVES: Cell loss during cardiac injection and hostility of the host-tissue microenvironment have the potential to diminish the overall effect of stem cell therapy. The purposes of this study were to evaluate the effect of a hypoxic preconditioning of mesenchymal stromal cells (MSC), to determine its safety and effectiveness, and to improve the efficacy of cell therapy using MSC in the setting of chronic myocardial ischaemia in swine. METHODS: Myocardial ischaemia was induced by an ameroid constrictor. Human MSC were cultured under normoxic (20% O2) or hypoxic conditions (1.5% O2) before transplantation. One month after ischaemia, pigs were randomly assigned to saline injection (sham), and 1 × 10(6)/kg normoxic or hypoxic MSC transplantation into the ischaemic inferior-lateral zone. RESULTS: Twenty-seven pigs were operated on and the mortality rate was 33.3%. The remaining 18 animals were randomly assigned to sham (n = 4), normoxic (n = 8) or hypoxic MSC (n = 6) treatment. Global systolic (left ventricle ejection fraction, P = 0.04) and diastolic (E/Ea, P = 0.008) functions were increased in the hypoxic group compared with other groups. The peak of 2-dimensional longitudinal strain was less altered in the hypoxic group compared with other groups (P < 0.001). Haemodynamic data showed that dP/dT max was improved in the hypoxic group compared with the other group (P < 0.01). Capillary density was increased in the hypoxic group (P = 0.001). MSC density was significantly higher in the ischaemic zone in the hypoxic group (P < 0.01). CONCLUSION: MSC engraftment with hypoxic preconditioning significantly improves capillary density and cell survival, resulting in improvement in global, regional and diastolic left ventricular functions. This highlights the therapeutic potential of transplanting hypoxic-preconditioned MSC in the setting of chronic ischaemic heart failure.

Cardiac resynchronization therapy reduces metaboreflex contribution to the ventilatory response in heart failure population.

Background. Metaboreflex overactivation has been proprosed to explain exaggerated hyperventilation in heart failure population. We investigated the metaboreflex activation after cardiac resynchronization therapy (CRT). Methods. 10 heart failure patients (mean left ventricular ejection fraction (LVEF) 27 ± 4%) schedulded for CRT implantation were prospectively studied. At baseline and after 6 month follow up two maximal cardiopulmonary exercise tests with and without regional circulatory occlusion (RCO) during recovery were performed. RCO was achieved by inflation of bilateral upper thigh tourniquets 30 mmHg above peak systolic blood pressure during 3 minutes after peak exercise. Metaboreflex contribution to the ventilatory response was assessed as the difference in ventilatory data at the third minute during recovery between the two tests (Δ). Results. Patients had enhanced VE/VCO(2) slope (40 ± 9) and an evident metaboreflex contribution to the high ventilatory response (ΔVE: 3 ± 4 L/min; P = 0.05, ΔRR: 4.5 ± 4/min; P = 0.003 and ΔVE/VCO(2): 5.5 ± 4; P = 0.007). 6 months after CRT implantation, NYHA class, LVEF, peak VO(2) and VE/VCO(2) were significantly improved (1.4 ± 0.5; P < 0.001, 42 ± 7%; P < 0.001, 16.5 ± 3 mL/kg/min; P = 0.003; 33 ± 10; P = 0.01). Metaboreflex contribution to VE, RR, and VE/VCO(2) was reduced compared with baseline (P = 0.08, P = 0.01 and P = 0.4 resp.). Conclusion. 6 months after CRT metaboreflex contribution to the ventilatory response is reduced.

Ventilatory response and peak circulatory power: new functional markers of response after cardiac resynchronization therapy.

BACKGROUND: The minute ventilation/carbon dioxide production (VE/VCO(2)) slope and peak circulatory power, like peak oxygen consumption (VO(2)), possess strong prognostic values in heart failure but have not been studied after ventricular resynchronization. AIMS: In this retrospective study, we evaluated the evolution of ventilatory response, effort capacity, functional status, peak circulatory power and echocardiographic variables, 6 months after cardiac resynchronization therapy (CRT). METHODS: Thirty subjects (mean age, 60+/-12 years) underwent symptom-limited exercise testing (CPX) with ventilatory expired gas analysis before and 6 months after CRT. The VE/VCO(2) slope was measured from rest to the end of exercise. Echocardiography was performed in stable clinical and pharmacological conditions. RESULTS: Mean New York Heart Association (NYHA) status improved significantly from 2.9 to 1.8 (p<0.001). Significant improvements were seen in exercise tolerance (evaluated by peak VO(2); from 13.1+/-3.1 to 15.3+/-5.6 mL/kg/min, p=0.02), VE/VCO(2) slope (from 44.4+/-19.2 to 39.6+/-13.8, p=0.003) and maximal workload (from 74+/-24 to 82+/-26 W, p=0.02). Mean peak circulatory power improved from 1663+/-494 to 2125+/-1014 mmHgmL/kg/min (p=0.009). Mean left ventricular ejection fraction increased from 25% to 29% (p=0.01). Mean end-systolic and end-diastolic left ventricular volumes decreased significantly from 155 to 128 mL and from 203 to 179 mL, respectively (p<0.05). Mean mitral regurgitation grade improved from 1.4+/-1.0 to 1.1+/-0.9 (p=0.1). No strong correlation was found between echocardiographic changes and improvement in ventilatory efficiency (VE/VCO(2) slope; all r=0.15-0.24). Patients with narrow QRS complexes (<130 ms) did not show significant improvement in functional or echocardiographic variables other than NYHA status. CONCLUSION: Cardiac resynchronization therapy improved ventilatory and haemodynamic responses. Our results highlight the potential value of new functional variables such as ventilatory response and peak circulatory power as better markers for identifying responders to CRT.

Response to cardiac resynchronization therapy: the muscular metabolic pathway.

Background. Changes in peripheral muscle in heart failure lead to a shift from aerobic to early anaerobic metabolism during exercise leading to ergoreflex overactivation and exaggerated hyperventilation evaluated by the VE/VCO(2) slope. Methods. 50 patients (38 males, 59 ± 12 years) performed cardio-pulmonary exercise test with gaz exchange measurement and echocardiographic evaluation before and 6 months after CRT. Results. The peak respiratory exchange (VCO(2)/ VO(2)) ratio was significantly reduced from 1.16 ± 0.14 to 1.11 ± 0.07 (P < .05) and the time to the anaerobic threshold was increased from 153 ± 82 to 245 ± 140 seconds (P = .01). Peak VO(2), VE/VCO(2), peak circulatory power and NYHA were improved after CRT (13 ± 4 to16 ± 5 ml/kg/min (P < .05), 45 ± 16 to 39 ± 13 (P < .01), 1805 ± 844 to 2225 ± 1171 mmHg.ml/kg/min (P < .01) and 3 ± 0.35 to 1.88 ± 0.4 (P = .01)). In addition, left ventricular ejection fraction and end-systolic volumes were improved from 24 ± 8 to 29 ± 7% (P < .01) and from 157 ± 69 to 122 ± 55 ml (P < .01). Conclusion. We suggest that CRT leads to an increase in oxidative muscular metabolism and postponed anaerobic threshold reducing exaggerated hyperventilation during exercise.