Feasibility and value of two-dimensional volumetric stress echocardiography.

BACKGROUND: Stroke volume response during stress is a major determinant of functional status in heart failure and can be measured by two-dimensional (2-D) volumetric stress echocardiography (SE). The present study hypothesis is that SE may identify mechanisms underlying the change in stroke volume by measuring preload reserve through end-diastolic volume (EDV) and left ventricular contractile reserve (LVCR) with systolic blood pressure and end-systolic volume (ESV). METHODS: We enrolled 4735 patients (age 63.6±11.3 years, 2800 male) referred to SE for known or suspected coronary artery disease (CAD) and/or heart failure (HF) in 21 SE laboratories in 8 countries. In addition to regional wall motion abnormalities (RWMA), force was measured at rest and peak stress as the ratio of systolic blood pressure by cuff sphygmomanometer/ESV by 2D with Simpson's or linear method. Abnormal values of LVCR (peak/rest) based on force were ≤1.10 for dipyridamole (N.=1992 patients) and adenosine (N.=18); ≤2.0 for exercise (N.=2087) or dobutamine (N.=638). RESULTS: Force-based LVCR was obtained in all 4735 patients. Lack of stroke volume increase during stress was due to either abnormal LVCR and/or blunted preload reserve, and 57% of patients with abnormal LVCR nevertheless showed increase in stroke volume. CONCLUSIONS: Volumetric SE is highly feasible with all stresses, and more frequently impaired in presence of ischemic RWMA, absence of viability and reduced coronary flow velocity reserve. It identifies an altered stroke volume response due to reduced preload and/or contractile reserve.

Feasibility and functional correlates of left atrial volume changes during stress echocardiography in chronic coronary syndromes.

An enlarged left atrial volume index (LAVI) at rest mirrors increased LA pressure and/or impairment of LA function. A cardiovascular stress may acutely modify left atrial volume (LAV) within minutes. Aim of this study was to assess the feasibility and functional correlates of LAV-stress echocardiography (SE) Out of 514 subjects referred to 10 quality-controlled labs, LAV-SE was completed in 490 (359 male, age 67 ± 12 years) with suspected or known chronic coronary syndromes (n = 462) or asymptomatic controls (n = 28). The utilized stress was exercise in 177, vasodilator in 167, dobutamine in 146. LAV was measured with the biplane disk summation method. SE was performed with the ABCDE protocol. The intra-observer and inter-observer LAV variability were 5% and 8%, respectively. ∆-LAVI changes (stress-rest) were negatively correlated with resting LAVI (r = - 0.271, p < 0.001) and heart rate reserve (r = -.239, p < 0.001). LAV-dilators were defined as those with stress-rest increase ≥ 6.8 ml/m2, a cutoff derived from a calculated reference change value above the biological, analytical and observer variability of LAVI. LAV dilation occurred in 56 patients (11%), more frequently with exercise (16%) and dipyridamole (13%) compared to dobutamine (4%, p < 0.01). At multivariable logistic regression analysis, B-lines ≥ 2 (OR: 2.586, 95% CI = 1.1293-5.169, p = 0.007) and abnormal contractile reserve (OR: 2.207, 95% CI = 1.111-4.386, p = 0.024) were associated with LAV dilation. In conclusion, LAV-SE is feasible with high success rate and low variability in patients with chronic coronary syndromes. LAV dilation is more likely with reduced left ventricular contractile reserve and pulmonary congestion.

Sport-specific influences on respiratory patterns in elite athletes / Influências específicas do esporte nos padrões respiratórios em atletas de elite

ABSTRACT OBJECTIVE: To examine differences in lung function among sports that are of a similar nature and to determine which anthropometric/demographic characteristics correlate with lung volumes and flows. METHODS: This was a cross-sectional study involving elite male athletes (N = 150; mean age, 21  4 years) engaging in one of four different sports, classified according to the type and intensity of exercise involved. All athletes underwent full anthropometric assessment and pulmonary function testing (spirometry). RESULTS: Across all age groups and sport types, the elite athletes showed spirometric values that were significantly higher than the reference values. We found that the values for FVC, FEV1, vital capacity, and maximal voluntary ventilation were higher in water polo players than in players of the other sports evaluated (p < 0.001). In addition, PEF was significantly higher in basketball players than in handball players (p < 0.001). Most anthropometric/demographic parameters correlated significantly with the spirometric parameters evaluated. We found that BMI correlated positively with all of the spirometric parameters evaluated (p < 0.001), the strongest of those correlations being between BMI and maximal voluntary ventilation (r = 0.46; p < 0.001). Conversely, the percentage of body fat correlated negatively with all of the spirometric parameters evaluated, correlating most significantly with FEV1 (r = −0.386; p < 0.001). CONCLUSIONS: Our results suggest that the type of sport played has a significant impact on the physiological adaptation of the respiratory system. That knowledge is particularly important when athletes present with respiratory symptoms such as dyspnea, cough, and wheezing. Because sports medicine physicians use predicted (reference) values for spirometric parameters, the risk that the severity of restrictive disease or airway obstruction will be underestimated might be greater for athletes.

RESUMO OBJETIVO: Analisar as diferenças na função pulmonar em atletas praticantes de esportes de natureza semelhante e determinar quais características antropométricas/demográficas se correlacionam com os fluxos e volumes pulmonares. MÉTODOS: Estudo transversal com atletas de elite do sexo masculino (N = 150; média de idade de 21  4 anos), praticantes de um dos quatro esportes investigados. Os atletas foram classificados de acordo com o tipo e a intensidade de exercício relacionado ao esporte. Todos os atletas foram submetidos a antropometria completa e testes de função pulmonar (espirometria). RESULTADOS: Em todas as faixas etárias e tipos de esporte, os atletas de elite apresentaram valores espirométricos significativamente maiores que os valores de referência. Os valores de CVF, VEF1, capacidade vital e ventilação voluntária máxima foram maiores nos praticantes de polo aquático que nos praticantes dos outros esportes avaliados (p < 0,001). Além disso, o PFE foi significativamente maior em jogadores de basquete do que em jogadores de handebol (p < 0,001). A maioria dos parâmetros antropométricos/demográficos apresentou correlações positivas com os parâmetros espirométricos avaliados. O IMC se correlacionou positivamente com todos os parâmetros espirométricos avaliados (p < 0,001), sendo a correlação mais forte entre o IMC e a ventilação voluntária máxima (r = 0,46; p < 0,001). De forma contrária, o percentual de gordura corporal se correlacionou negativamente com todos os parâmetros espirométricos, mais significativamente com VEF1 (r = −0,386; p < 0,001). CONCLUSÕES: Nossos resultados sugerem que o tipo de esporte praticado tem um impacto significativo na adaptação fisiológica do sistema respiratório. Esse conhecimento é particularmente importante quando os atletas apresentam sintomas respiratórios tais como dispneia, tosse e sibilância. Visto que os especialistas em medicina do esporte utilizam valores previstos (de referência) para os parâmetros espirométricos, o risco de se subestimar a gravidade de doença restritiva ou obstrução de vias aéreas pode ser maior nos atletas.

Left ventricular diastolic performance at rest is essential for exercise capacity in patients with non-complicated myocardial infarction.

INTRODUCTION: In patients with recent myocardial infarction (MI) limited exercise capacity during physical activity is an important symptom and the base for future treatment. The myocardial injury after MI leads to both systolic and diastolic left ventricular (LV) dysfunction. OBJECTIVE: The aim of this study was to assess the relevance of systolic and diastolic LV function for cardiopulmonary exercise capacity in patients with prior MI. METHODS: Sixty-five consecutive patients after first MI without signs and symptoms of heart failure, aged 52 ± 6 years, were included in the study. The following echo parameters were evaluated: LV ejection fraction (LVEF), peak early and late diastolic velocities (E, A), deceleration time of E wave (dec t E), ratio of early trans-mitral to early annular diastolic velocities (E/e'), velocity propagation of early filling (Vp), and diameters and volumes of LV and left atrium (LA). CPET variables included: oxygen uptake at peak exercise (peak VO2), oxygen pulse (VO2 HR), VE/VCO2 slope, circulatory power (CP) and recovery half time (T1/2). RESULTS: Significant correlations were demonstrated between peak VO2 and E/e' (p < 0.001), peak VO2 and dec t E (p < 0.001), VO2 HR and E/e' (p = 0.002) and between VE/VCO2 and E/e' (p < 0.001). Twenty patients with elevated LV filling pressure achieved significantly lower peak VO2 (1624 vs. 1932 ml, p = 0.027) VO2 HR (11.70 vs. 14.05, p = 0.011) and CP (287,073 vs. 361,719, p = 0.014). By using multivariate regression model we found that only E/e' (p = 0.001) and dec t E (p = 0.008) significantly contributed to peak VO2. CONCLUSIONS: Diastolic dysfunction, particularly LV filling pressure, determine exercise capacity, despite differences in LV ejection fraction in patients with prior MI.