Comparison of free range and graded exercise testing.

Previous studies with athletes have demonstrated greater physiologic responses during free range (FR) compared with graded (GXT) exercise testing. Since the sensitivity of clinical exercise testing depends upon the magnitude of physiologic responses, we sought to determine whether FR might provoke greater responses than GXT in nonathletic individuals and patients. Healthy, physically active nonathletes and clinically stable CHD patients (N = 12) performed GXT on cycle ergometer (15 W + 15 W.min-1) and FR (minimal time for 75 kJ task) on a cycle ergometer. A starting power output was recommended for FR, but the patients were free to pedal at their own rates. During FR, VO2max (36.5 +/- 10.1 vs 34.1 +/- 9.4 mL.min-1.kg-1), HRmax (156 +/- 25 vs 144 +/- 27 beats.min-1), double product (31.4 +/- 4.9 vs 29.1 +/- 5.9) and VEmax (111 +/- 26 vs 94 +/- 17 L.min-1) were all significantly greater than during cycle GXT. The mean peak power output during GXT (180 +/- 45 W) was not significantly different than the mean power output during FR (204 +/- 45 W). During FR, successive "0.5 mile laps" (approximately 12.5 kJ) were accomplished at power outputs of 217 +/- 45, 217 +/- 52, 192 +/- 60, 194 +/- 65, 199 +/- 63, and 207 +/- 63 W. No patient experienced angina or ECG changes during either FR or GXT. The patients uniformly reported that FR felt like "hurrying" in the real world. Some patients had to make large reductions in their power output in mid ride to allow recovery from a too aggressive start, much as they would in the real world. We conclude that FR exercise provides a clinically useful method of exercise testing that is not only more like real world exercise patterns but also provokes greater physiologic responses than are achievable during conventional GXT.

Predicting functional capacity during treadmill testing independent of exercise protocol.

Clinically useful estimates of VO2max from treadmill tests (GXT) may be made using protocol-specific equations. In many cases, GXT may proceed more effectively if the clinician is free to adjust speed and grade independent of a specific protocol. We sought to determine whether VO2max could be predicted from the estimated steady-state VO2 of the terminal exercise stage. Seventy clinically stable individuals performed GXT with direct measurement of VO2. Exercise was incremented each minute to optimize clinical examination. Measured VO2max was compared to the estimated steady-state VO2 of the terminal stage based on ACSM equations. Equations for walking or running were used based on the patient's observed method of ambulation. The measured VO2max was always less than the ACSM estimate, with a regular relationship between measured and estimated VO2max. No handrail support: VO2max = 0.869.ACSM -0.07; R2 = 0.955, SEE = 4.8 ml.min-1.kg-1 (N = 30). With handrail support: VO2max = 0.694.ACSM + 3.33; R2 = 0.833, SEE = 4.4 ml.min-1.kg-1 (N = 40). The equations were cross-validated with 20 patients. The correlation between predicted and observed values was r = 0.98 and 0.97 without and with handrail support, respectively. The mean absolute prediction error (3.1 and 4.1 ml.min-1.kg-1) were similar to protocol-specific equations. We conclude that VO2max can be predicted independent of treadmill protocol with approximately the same error as protocol-specific equations.

Temas de ecocardiográfía: IV. Diagnóstico ecocardiográfico de aneurisma coronario en enfermedad de Kawasaki; presentación de dos casos / Echocardiography: IV. Echocardiographic diagnosis of coronary aneurism in Kawasaki diseases; report of 2 cases

Se presentan dos casos de síndrome mucocutáneo (enfermedad de Kawasaki), con afectación aneurismática del origen de la coronaria izquierda, diagnosticado mediante ecocoardiografía bidimensional. La fiabilidad del estudio ecocardiográfico, en nuestros casos, frente a la mortalidad de la angiografía, en el estadio agudo de la enfermedad, nos inclina a considerar el estudio ecocardiográfico como un método diagnóstico idóneo en esta patología (AU)

Temas de ecocardiográfía: IV. Diagnóstico ecocardiográfico de aneurisma coronario en enfermedad de Kawasaki; presentación de dos casos / Echocardiography: IV. Echocardiographic diagnosis of coronary aneurism in Kawasaki diseases; report of 2 cases

Se presentan dos casos de síndrome mucocutáneo (enfermedad de Kawasaki), con afectación aneurismática del origen de la coronaria izquierda, diagnosticado mediante ecocoardiografía bidimensional. La fiabilidad del estudio ecocardiográfico, en nuestros casos, frente a la mortalidad de la angiografía, en el estadio agudo de la enfermedad, nos inclina a considerar el estudio ecocardiográfico como un método diagnóstico idóneo en esta patología