Excessive blood pressure increase with exercise and risk of all-cause mortality and cardiac events

The association of an excessive blood pressure increase with exercise (EBPIE) on cardiovascular outcomes remains controversial. We sought to assess its impact on the risk of all-cause mortality and major cardiac events in patients with known or suspected coronary artery disease (CAD) referred for stress testing. Exercise echocardiography was performed in 10,047 patients with known or suspected CAD. An EBPIE was defined as an increase in systolic blood pressure with exercise ≥80 mmHg. The endpoints were all-cause mortality and major cardiac events (MACE), including cardiac death or nonfatal myocardial infarction (MI). Overall, 573 patients exhibited an EBPIE during the tests. Over a mean follow-up of 4.8 years, there were 1,950 deaths (including 725 cardiac deaths), 1,477 MI, and 1,900 MACE. The cumulative 10-year rates of all-cause mortality, cardiac death, nonfatal MI and MACE were 32.9%, 13.1%, 26,9% and 33% in patients who did not develop an EBPIE vs. 18.9%, 4.7%, 17.5% and 20.7% in those experiencing an EBPIE, respectively (p <0.001 for all comparisons). In Cox regression analyses, an EBPIE remained predictive of all-cause mortality (hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.59-0.91, p = 0.004), cardiac death (HR 0.67, 95% CI 0.46-0.98, p = 0.04), MI (HR 0.67, 95% CI 0.52-0.86, p = 0.002), and MACE (HR 0.69, 95% CI 0.56-0.86, p = 0.001). An EBPIE was associated with a significantly lower risk of mortality and MACE in patients with known or suspected CAD referred for stress testing.

Valor pronóstico del incremento de la tensión arterial sistólica con el ejercicio en pacientes hipertensos con enfermedad coronaria conocida o sospechada.

La asociación entre un incremento exagerado de la presión arterial sistólica con el ejercicio (IEPASE) y la probabilidad de eventos cardiovasculares es controvertida. Nuestro propósito fue determinar la posible asociación de un IEPASE con la supervivencia y con el riesgo de eventos cardíacos graves en pacientes hipertensos con enfermedad coronaria conocida o sospechada. Se trata de un estudio retrospectivo y observacional sobre una muestra de 5.226 pacientes con historia de hipertensión arterial y enfermedad coronaria conocida o sospechada referidos a ecocardiografía de ejercicio. El IEPASE se definió como un incremento de la presión arterial sistólica con el ejercicio igual o superior al percentil 95 de esta población (80 mmHg). Los objetivos fueron mortalidad total, mortalidad de origen cardíaco e infarto de miocardio (IM). En un seguimiento medio de 4,7 años, se registraron 978 muertes (371 de origen cardíaco) y 798 IM. Las tasas anuales de mortalidad, mortalidad de origen cardíaco e IM fueron del 2,73; 0,83 y 2,63% en pacientes con IEPASE y de 4,4; 1,58 y 3,98%, respectivamente en aquellos sin IEPASE (p < 0,001; p = 0,012 y p = 0,014, respectivamente). Tras un ajuste multivariado, el IEPASE resultó predictor de mortalidad por cualquier causa (HR: 0,70; IC 95%: 0,52-0,95; p = 0,023) e IM (HR: 0,69; IC 95%: 0,50-0,95; p = 0,022), pero la asociación con mortalidad cardiaca no alcanzó significación estadística (HR: 0,72; IC 95%: 0,43-1,20; p = 0,2). El IEPASE se asoció con mayor probabilidad de supervivencia y menor riesgo de IM en pacientes hipertensos con enfermedad coronaria conocida o sospechada.

Rodent models for resolving extremes of exercise and health

The extremes of exercise capacity and health are considered a complex interplay between genes and the environment. In general, the study of animal models has proven critical for deep mechanistic exploration that provides guidance for focused and hypothesis driven discovery in humans. Hypotheses underlying molecular mechanisms of disease, and gene/tissue function can be tested in rodents in order to generate sufficient evidence to resolve and progress our understanding of human biology. Here we provide examples of three alternative uses of rodent models that have been applied successfully to advance knowledge that bridges our understanding of the connection between exercise capacity and health status. Firstly we review the strong association between exercise capacity and all-cause morbidity and mortality in humans through artificial selection on low and high exercise performance in the rat and the consequent generation of the "energy transfer hypothesis". Secondly we review specific transgenic and knock-out mouse models that replicate the human disease condition and performance. This includes human glycogen storage diseases (McArdle and Pompe) and α-actinin-3 deficiency. Together these rodent models provide an overview of the advancements of molecular knowledge required for clinical translation. Continued study of these models in conjunction with human association studies will be critical to resolving the complex gene-environment interplay linking exercise capacity, health, and disease.